The Transformation of Sleep Medicine
Like many doctors fascinated by new medical technology, I have succumbed to “me-search”: the urge to use new technology to study myself. Me-search optimizes my own health and teaches me how to use new technology to help patients.
Last October at a medical conference, I learned about Empower Sleep, a new sleep medicine telehealth company. Empower Sleep promises to transform sleep medicine using a device called the SleepImage Ring.
I’ve always struggled with sleep due to a smorgasbord of areas for improvement:
- Nasal obstruction due to hay fever
- Bruxism (nocturnal teeth grinding)
- Nocturia (arising more than once a night to urinate)
- Light sleeping (more sensitive to disruption from environmental stimuli)
- Advanced sleep phase disorder (arising too early in the morning)
- Preterminal insomnia (awakening before the end of the night, often associated with depressive illness)
Me-search overtook me. I had to try the SleepImage Ring for myself.
(Disclaimer: I have no financial interest in SleepImage or Empower Sleep. I do refer patients to Empower Sleep for treatment.)
What We’ve Learned About Sleep
From time immemorial, sleep was thought to be an inactive state between wakefulness and death. Sleep was understood as a passive, inactive state defined by lack of consciousness. Dreams represented a peek into this realm and were thought to carry mystical, psychological, and/or religious meaning.
In 1928, we gained the ability to peer into sleep’s biology when German psychiatrist Hans Berger developed a way to record the electrical activity of the brain’s neurons. The electroencephalogram (EEG) revealed distinctive waves of neuronal activity unique to sleep.
By the 1950s, an EEG-defined sleep phase associated with rapid eye movements (REM) and dreaming had been characterized, and the concept of sleep architecture was born. By the 1960s, EEG-based polysomnograms (PSG) were used to diagnose and treat sleep disorders.
We now know that sleep occurs in 90-minute cycles that repeat through the night. Each cycle contains lighter portions, S1 and S2, and deeper portions, S3, called slow-wave sleep (SWS). Each cycle also contains REM sleep and brief arousals.
The composition of those 90-minute cycles changes throughout the night: more slow-wave sleep occurs early, and more REM sleep occurs later. The amount of slow-wave sleep diminishes as we age, while the percentage of REM sleep is preserved.
Many other factors can affect sleep’s composition, including:
- Illnesses such as obstructive sleep apnea (OSA)
- Medications such as benzodiazepines (drugs like Valium)
- Beverages such as alcohol
The Current State of Sleep Testing
EEG-based polysomnograms have been the dominant method of diagnosing sleep disorders for over 50 years, forming the foundation of sleep medicine. However, a polysomnogram is an extremely cumbersome test.
The patient must travel to a special overnight clinic and fall asleep with 22 separate wires attached to their body, which measure:
- Brain wave activity
- Airflow
- Eye movement
- Oxygen saturation
- Heart rate and rhythm
- Muscle tone in the chin, chest wall, and legs
Newer home sleep studies have reduced the number of attachments needed and allowed the patient to sleep in their own bed. However, both in-clinic and at-home studies may influence the sleep being measured.
Think about how well you slept last week. For most of us, the night-to-night experience of sleep varies. Any single night of sleep (let alone with 22 wires attached!) may not represent a typical night.
Neither in-clinic nor at-home tests are practical for multiple nights of testing. Repeating a study allows for the assessment of treatment modalities and sets up a series of trial-and-error experiments to optimize sleep.
Fortunately, we’re amidst a quiet revolution in our understanding of sleep’s physiology.
The Sleep Revolution
For the last hundred years, we’ve classified sleep based on the brain’s electrical activity as measured by an electroencephalogram. However, sleep entails not just brain activity but characteristic changes throughout the entire body, including breathing, heart rate, blood pressure, and body temperature.
About 15 years ago, researchers began developing a new method for analyzing sleep based on changes that occur to our autonomic nervous system (ANS). The autonomic nervous system is a network of nerves that regulate unconscious processes that keep our body functioning, including breathing, digestion, and heart pumping.
The autonomic nervous system is divided into two categories: the sympathetic (SNS) and parasympathetic (PNS) nervous systems:
- The sympathetic nervous system mediates our “fight or flight” response — increasing our breathing rate, shunting blood to our muscles, making the heart pump harder, and putting more fuel into the bloodstream for muscular activity.
- The parasympathetic nervous system mediates “rest and digest” functions such as improving blood flow to the digestive tract and secreting digestive enzymes.
The sympathetic and parasympathetic nervous systems exist in a delicate balance, as every organ receives signals from both systems.
For example, in the cardiopulmonary system (heart and lungs), signals oscillate back and forth in a teeter-totter fashion, and each breath subtly alters the heart rate:
- During each breath in, called inspiration, the sympathetic nervous system predominates and slightly speeds up the heartbeat.
- During each breath out, called expiration, the parasympathetic system slightly predominates and slightly slows down the heartbeat.
Thus, continuous recording of every heartbeat demonstrates variation in timing that correlates with the respiration rate. Exactly how much variability reflects the strength of the sympathetic nervous system’s input relative to the parasympathetic nervous system’s. A stronger parasympathetic nervous system creates more variability and correlates with better health outcomes.
Breathing also affects the amount of blood pumped each time the heart contracts. Each heartbeat during expiration moves a bit more blood than each heartbeat during inspiration.
A new technique called cardiopulmonary coupling (CPC) generates one waveform reflecting the change in heart rate and a second waveform reflecting the change in blood output. By analyzing the relationship between these two waveforms, researchers assess how the autonomic nervous system functions during sleep.
Cardiopulmonary coupling is a brand-new lens we can use to view sleep. EEG describes sleep from the vantage point of the brain’s wave changes, while cardiopulmonary coupling divides sleep into different stages based on differences in the autonomic nervous system.
CPC vs. PSG: What’s the Difference?
Cardiopulmonary coupling results and polysomnogram results classify non-REM sleep (NREM) differently.
The traditional polysomnogram-based classification divides non-REM sleep into three stages of progressive depth:
- Stages 1 and 2 describe a lighter level of sleep (for example, your spouse accuses you of falling asleep in front of the TV; you deny it but can’t recall the plot).
- Stage 3 is a deeper stage of sleep referred to as slow-wave sleep based on brain wave activity. This stage aids memory, immune function, tissue repair, and metabolic balance.
Meanwhile, cardiopulmonary coupling categorizes non-REM sleep into stable and non-stable components. Stable non-REM correlates with slow-wave sleep but possibly provides a more accurate measure of this physiologically vital sleep stage.
The biggest advantage of cardiopulmonary coupling over polysomnograms is the ease of testing. A small rubber ring worn on your finger (like the SleepImage Ring, which uses cardiopulmonary coupling) provides almost as much information as 22 bulky wires (as in the case of a polysomnogram).
How Does the SleepImage Ring Work?
The SleepImage Ring harnesses an amazing new technology called photoplethysmography (PPG). Photoplethysmography powers our current array of consumer wearable devices, including the Fitbit, Garmin watch, Oura Ring, and WHOOP band, as well as medical grade, FDA-approved wearables such as the SleepImage Ring.
Photoplethysmography shines very small LED lights into the skin, illuminating tiny arteries under the surface. Adjacent sensors measure the reflected LED light, tracking the pulsatile pressure waves in the subcutaneous arteries and the color of the hemoglobin (oxygen-carrying protein) in the blood.
The pressure waves’ timing and amplitude measure the autonomic nervous system’s performance, and the hemoglobin’s color in the blood measures how well the lungs deliver oxygen to the body. The SleepImage Ring can also measure nocturnal movement and skin temperature.
Combining these data points paints a thorough picture of a person’s sleep. How many awakenings were there overnight? How much time was spent in vital stages such as REM and stable non-REM? Are there episodes of low oxygen indicating obstructive sleep apnea?
My SleepImage Experience
I started using the SleepImage Ring, hoping to gain insights that would minimize my sleep challenges. To my dismay, I discovered two new areas for improvement I’d been unaware of: a mild case of obstructive sleep apnea and an imbalance of my autonomic nervous system during non-REM sleep.
After monitoring multiple nights of sleep, my SleepImage Ring provided an assessment of my mild obstructive sleep apnea that was much more accurate than my one prior polysomnogram.
The SleepImage Ring tracked a tremendous amount of variation in the apnea-hypopnea index (AHI), the number of times per hour my breathing was compromised, ranging from 3 (normal) to 22 (moderate severity). My average was about 10, or mild.
Interestingly, in the traditional polysomnogram I underwent about 10 years ago, I struggled to sleep and the test revealed an apnea-hypopnea index of 5 (high normal). I suspect this is because the polysomnogram yielded only one night of compromised data.
Disheartened about receiving yet another sleep impairment diagnosis, I worked with Empower Sleep to use their cardiopulmonary coupling technology to address the problem. Not only is the SleepImage Ring better at diagnosing illnesses than polysomnograms are, but it also provides a better route for treating those illnesses.
Because my obstructive sleep apnea was mild, there was a good chance it could be treated without a CPAP machine. I was given a list of alternative therapies to try to reduce obstruction of my upper airway.
I incrementally added treatment modalities: nasal steroids to shrink the nasal mucosa and widen the opening of the nasal passages; lip tape to close my mouth, which pinched the tongue to prevent it from falling backward and obligated nasal breathing; and a soft rubber nasal device that further opens my nasal passages and reduces obstruction.
My bedtime routine has become more involved, and I’ve become quite a sight to behold in bed. But the process works! I now have several months of SleepImage data demonstrating the progressive reduction in my apnea-hypopnea index.
There’s still a fair amount of variation in my apnea-hypopnea index, but the average is now only a bit above normal. More importantly, I have more energy during the day.
My second discovery, an autonomic nervous system imbalance during non-REM sleep, represents a more complicated challenge because it’s a new disorder. Before the advent of cardiopulmonary coupling, autonomic nervous system impairments weren’t diagnosed by tracking sleep stages.
Because the disorder is so new, we don’t have good assessments of normal values associated with aging. There are only clues. We do know that EEG-based slow-wave sleep does somewhat correlate with the stable non-REM sleep stage.
We also know that slow-wave sleep declines with age. Therefore, we expect our autonomic nervous system’s function to decline, as well. Unfortunately, just as our skin gets “old and wrinkly” with age, so does our sleep.
Does my impaired autonomic nervous system function during sleep represent a normal age-related change, or can I improve it? As an athlete, I want to maximize the stable non-REM fraction of my sleep. That’s when “all the good stuff happens,” particularly the release of testosterone and growth hormone.
Unlike my clear victory over obstructive sleep apnea, I’m still working to overcome my impaired autonomic nervous system. I’ve expanded my meditation practice, targeting 20 minutes in the morning and 12 minutes before bedtime. (If you’d like to join me, review my step-by-step meditation guide.)
I’m also trying a very low dose of the antidepressant Lexapro, which I’ve used successfully to treat mild depression in the past. I’m not currently depressed, but there is a high probability that depression may be associated with a distinctive form of autonomic nervous system dysfunction during sleep.
My sleep data may represent a low-grade depression that medication can improve. The jury is still out on these interventions — I’ll keep you posted.
My Take on the SleepImage Ring
The SleepImage Ring represents a transformation in sleep medicine. More patients can be conveniently screened for sleep disorders, and more people can be effectively treated, especially those with obstructive sleep apnea.
Previously, only those with obvious obstructive sleep apnea symptoms underwent testing. Many people have the illness and don’t know it — I was one of them. They can now be diagnosed through greater use of sleep testing.
Also, less than half of people who are prescribed a CPAP machine to treat their obstructive sleep apnea can tolerate using it. Now we can use a trial-and-error method to build effective treatment regimens for those with mild and moderate obstructive sleep apnea, sparing them a CPAP machine.
The sleep medicine revolution has begun!
Exercise — The Real Fountain of Youth
In my last blog post, I introduced the Metric-Driven Empowerment Cycle (MDEC, pronounced “em-deck”), in which new health-monitoring technologies provide actionable data that informs behavior modification, which improves the patient’s health. MDEC-based healthcare focuses on preventing illness rather than simply treating it.
Most of the time, that data-informed behavior modification includes some form of exercise.
Exercise’s Impact on Heart Disease
Physicians have been prescribing exercise as medicine since Hippocrates’ day, but exercise benefits weren’t researched until 1953, when British epidemiologist Dr. Jeremy Morris studied transit workers on double-decker buses.
Dr. Morris compared the rate of coronary heart disease (CHD) among bus drivers, who sat for 90% of their shift, with conductors, who climbed over 600 steps a day. The sedentary drivers’ CHD rate was 42% higher than the conductors’.
Dr. Morris confirmed these findings in another study. He compared the rate of CHD among postal workers with desk jobs against that of workers who walked to deliver the mail. The former group had a 33% higher CHD rate.
Dr. Jeremy Morris died in 2009 at age 99. He swam, jogged, and cycled well into his old age.
We now have many decades of literature documenting the staggering health benefits of exercise. It reduces the risk of dementia, mitigates the effects of menopausal hot flashes, minimizes depression, prevents diabetes... I could go on.
Despite the billions of dollars spent on anti-aging drug research, exercise remains the best route we have to the mythical “Fountain of Youth.”
How Exercise Has Helped Me
I’m an avid cyclist. I’ve pedaled thousands of miles in my life, and I’m convinced that my many decades of commitment to fitness have reduced the impact of my genetic predisposition to cardiometabolic disease.
Obesity and diabetes run down both sides of my family tree. Both my parents were physically active, not overweight, and didn’t have diabetes or coronary heart disease. However, all their siblings were overweight and had manifestations of cardiometabolic disease such as high blood pressure, diabetes, and coronary heart disease.
In attempting to practice what I preach, I devote considerable effort to cardiovascular and strength training, working to maintain a normal weight with healthy levels of muscle and fat mass. Nonetheless, my parameters, such as blood pressure, cholesterol levels, and glucose levels, are still borderline — not the levels one would expect given my level of fitness and body composition.
I’m working hard against my genes. For both personal and professional reasons, I’m passionate about exercise’s role in maximizing health and longevity.
I look forward to helping all my patients set personal records and achieve athletic goals. Of course, the greatest gains will accrue to those who are currently the least fit.
The Exercise Dose-Response Curve
The human body is a machine that has evolved for movement. An inactive machine will rapidly break down, i.e., our bodies will devolve into a diseased state if we don’t keep moving.
None of our vital structures will operate appropriately. The heart won’t pump as efficiently. The joints will become stiff and more susceptible to injury. The body can go into caloric excess with surplus energy stored as fat, which gets distributed into abnormal locations such as the liver and muscle cells, creating inflammation and insulin resistance. And so on.
Fortunately, just as physical inactivity can trigger a negative cascade of events, physical activity can reverse the process.
There is an exercise dose-response curve that describes how health benefits change with increasing quantities of both cardiovascular and strength training exercise:
- The first section of the curve has a steep upward slope, reflecting a region that is the “best deal,” or the most improvement in health for even a minimal increase in exercise.
- The next region has a wide range of quantities of exercise in which “more is better” in terms of benefit.
- A small section of the maximum amount of exercise reflects a region in which “more is worse.”
Exercise is the most valuable for the least fit. For these people, exercise corrects a diseased, malfunctioning body. Those with higher levels of fitness can still improve their health but don’t have the same magnitude of dysfunction that needs to be addressed.
Once you advance beyond the steep upslope that rescues the physically inactive, the curve climbs appreciably before flattening. In this region of the curve, incrementally more fitness brings additional health benefits.
Large epidemiological studies illustrate this association by examining the link between longevity and VO2 max, the maximum volume of oxygen your body can use during peak exertion. VO2 max represents the fitness of your entire cardiopulmonary system, which is improved through exercise.
These studies demonstrate a consistent, stepwise improvement in longevity, beginning with the lowest rung of fitness and continuing to the top tier. In fact, the magnitude of benefit from moving from least fit to moderately fit (not even the top tier!) exceeds the reduction in mortality risk of quitting cigarettes or overcoming diabetes. Strength training and muscle mass maintenance also benefit the preservation of function and longevity.
Eventually, the graph slopes downward, which applies to extreme athletes (who compete and train for intense long-distance events, such as running an ultramarathon). They can train so hard that they overwhelm the stress/recovery cycle, creating a chronic inflammatory state with deleterious health effects.
This group comprises a minute fraction of the population but illustrates the concept that “too much of a good thing may no longer be a good thing.”
Final Thoughts
My goal is to see everyone reap the benefits of increased exercise. I also want to keep an eye out for those who may be overtraining.
Of course, the devil is in the details. Creating appropriate training regimens and motivating everyone will be an exciting professional challenge. Exercise will become the foundation of Medicine 3.0 at Banner Peak Health!
Medical Innovation — Our Approach
I’m a huge fan of physician Peter Attia, author of the book Outlive. He’s used his popularity to reshape the vocabulary of preventative medicine.
Attia defines “healthspan” as the number of years we can live with a high level of function, as opposed to “lifespan,” which is the number of years we’re alive regardless of health status.
He’s also coined the terms “Medicine 2.0” and “Medicine 3.0.” The former, a reactive, disease-based approach, treats existing illnesses. The latter prevents illness from developing by using a far-sighted approach.
Attia has become one of the best-known proponents of the “Longevity Medicine” movement, focusing on how to help people lead longer and more fulfilling lives. Prevention has always been a core aspect of primary care medicine, but Peter Attia has refocused its goals and created a growing demand for a more sophisticated level of prevention than has been available in traditional medicine.
Inspired by Peter Attia, I want to bring state-of-the-art preventative healthcare to Banner Peak Health, practice Medicine 3.0, and maximize patients’ healthspan.
Introducing the Metric-Driven Empowerment Cycle
I studied political economy as an undergraduate, focusing on how political and economic forces shape our society. I’ve retained this vantage point throughout my medical career.
In my last blog post, I described the term “diagnostic desert,” analogous to the term “food desert,” which is the scarcity of grocery stores in lower socio-economic neighborhoods. With no lucrative drug, surgery, or diagnostic procedure, vast areas of our healthcare system are underserved.
Most preventative healthcare falls into this category. Tragically, our current system incentivizes doctors to prescribe patients medication rather than work with those patients to help them live healthier lives.
Pharmacology plays a vital role in prevention, particularly in reducing the risk of hypertension and elevated cholesterol. However, our most potent tools for overall risk reduction stem from how we eat, sleep, exercise, and handle stress.
Practicing medicine at this level appears old-fashioned and low-tech. However, recent technological advances have enabled convenient, real-time, continuous monitoring of biomarkers in these areas. A small ring can measure the physiology of your sleep. A patch on your arm can record how your blood sugar varies throughout the day. By recording actionable data, these technologies provide the tools to fine tune and enhance the wearer’s health.
Harnessing these technological tools, we can follow a reiterative process to increase healthspan:
- Identify the health status to be improved
- Optimally measure the health status
- Use the diagnostic information to modify behavior
- Watch the new behavior improve health status
- Rinse and repeat
This cycle represents the foundation of preventative care at Banner Peak Health. We call it the Metric-Driven Empowerment Cycle (MDEC).
For example, we have a general sense of the quantity of sleep we get. When was bedtime? When did the alarm go off? Any awakenings during the night? However, our quality of sleep is unknown. By definition, we are unconscious when we sleep. Sleep is made up of restorative phases, such as REM and deep sleep, which conditions such as obstructive sleep apnea can disrupt.
Now, consumer wearables and medical devices allow the ongoing assessment of sleep quantity and quality. This technology allows us to diagnose potential problems and monitor and adjust treatment strategies.
Optimizing metabolic health offers another important area for monitoring technology. We know that elevated glucose (sugar) levels are associated with diabetes mellitus, which is a risk factor for many bad outcomes, including heart disease and strokes. However, pre-diabetes, a condition of insulin resistance but not full-fledged diabetes, can confer a significant risk of these bad outcomes as well. An estimated one in three adults in the United States is pre-diabetic.
New wearable technology can diagnose and manage this extremely common, “hidden” risk factor. A continuous glucose monitor remains on the skin for 10–14 days, noting glucose levels every five minutes. The monitor sends that data to a smartphone, which allows highly personalized diagnosis and treatment.
It’s yet another example of the MDEC:
Final Thoughts
The Metric-Driven Empowerment Cycle provides a new paradigm of care at Banner Peak Health. Now, we can offer the highest quality of care for our patients: medical care that prioritizes prevention and empowers patients by blending the latest medical technology with an old-fashioned determination to work hard.
We want patients to live longer and better!
Own Your Blood Pressure (and Get More Accurate Readings)
Asking, “What’s my blood pressure?” is like asking, “What’s the weather like in Omaha, Nebraska?”
The weather in Omaha can change from minute to minute and depends on many variables, including the season and time of day. Your blood pressure is the same and can vary depending on a wide array of variables including emotions, activity, sleep, pain, and beverages such as coffee and alcohol products.
Blood pressure is the pressure exerted by circulating blood against the blood vessel walls. When the heart contracts, blood pressure peaks. As the heart relaxes, blood flows into the heart chambers, reducing blood pressure.
We describe blood pressure using a larger number over a smaller number. The larger number is the peak blood pressure during the squeeze, or the systolic phase. The smaller number is the low point of pressure as the heart relaxes, or the diastolic phase.
Our current definition of “normal” blood pressure is less than 120 over 80. “High blood pressure,” or hypertension, occurs in stages and puts you at a greater risk for a constellation of bad health outcomes, including:
- Kidney failure
- Stroke
- Heart failure
- Heart attack
- Heart arrhythmia
Therefore, it’s vital to accurately measure blood pressure and treat it in order to help prevent these clinical outcomes.
It’s also essential to understand that the journey to these bad outcomes begins with mildly elevated pressure, which leads to stiffer blood vessels that require higher blood pressure to move the blood, which causes the vessels to stiffen further, and so on. The progressive loss of elasticity becomes a feed-forward loop. The earlier we can interrupt the pattern of elevated blood pressure, the more we can reduce the risk of bad outcomes.
The Challenge of Measuring Accurately
Returning to our weather metaphor, just as the weather changes constantly, so does your blood pressure. Throughout the day, your blood pressure goes through peaks and valleys, resembling a seismogram during an earthquake.
The variability results from circumstances such as your activity level, food and drink choices (caffeine and alcohol can affect blood pressure), stress level, and technicalities regarding how you measure your blood pressure.
To record “accurate” blood pressure, a person:
- Should be at rest for at least five minutes
- Must abstain from caffeine, alcohol, and cold medicines
- Must sit upright in a chair that supports the torso, legs uncrossed, with their feet flat on the floor
- Must not be in pain or dizzy
- Must keep the blood pressure cuff at the level of their heart
Meeting the Challenge
The following common scenarios can lead to erroneous blood pressure readings:
- Sitting in traffic on the way to the doctor (high stress increases blood pressure)
- Experiencing a symptom (e.g., a headache)
- Placing the blood pressure cuff lower than the heart
- Drinking alcohol the night before
- Drinking coffee the morning of
- Taking an NSAID the morning of (increases blood pressure)
SPRINT Study
When I read medical literature, I ask myself whether the intervention described in the study applies to what occurs in my clinic. Sometimes, it’s not even close.
Take the SPRINT study, which demonstrated that patients with elevated blood pressure whose treatment resulted in a systolic blood pressure of less than 120 had one-third the risk of stroke, heart attack, and major adverse cardiac and cerebrovascular events compared to those who were treated to the target of 140.
This study created the rationale for our current blood pressure target guidelines. However, researchers involved in the study measured blood pressure very differently than the standard practice.
Study participants would enter a room and sit quietly for five minutes before a machine automatically took their blood pressure. They’d continue to sit quietly as the machine took their blood pressure at five-minute intervals for 15 minutes. The three measurements were averaged.
This scenario is nothing like a the usual clinical context — no nurses, no doctors entering or leaving the room, etc. It’s exceptionally difficult to replicate in a real-world application. The study’s results achieved lower blood pressure, but only in specific circumstances.
Be an Active Participant
So, how can we get more accurate blood pressure readings?
First, we must understand that blood pressure readings taken in a clinical environment, such as in a doctor’s office during a standard appointment, are often inaccurate.
Patients need to measure their blood pressure on their own at home. Follow these tips:
- Use a high quality machine such as the OMRON cuff.
- Choose an environment where you can rest comfortably and meet the other requirements for an accurate reading (as listed above).
- Take three readings every five minutes and average the final two.
- Take your cuff to your doctor’s office to calibrate it with their manual cuff and stethoscope method.
Any time you have your blood pressure taken, be an active participant. Point out the conditions that may affect your reading and take steps to ensure as much accuracy as possible.
Gut Microbiome: How Do I Know if I Need a Probiotic?
In 2022, the Global Probiotics Market was worth $77.1 billion. I hear questions like “How do I know if I need a probiotic?” from my patients almost daily.
Probiotics are live microorganisms delivered in adequate amounts to confer health benefits. Although medical literature links changes in our gut microbiome to everything from mental health to inflammatory diseases, there’s still much we need to explore.
We have yet to perform enough randomized control trials to demonstrate most of these benefits. Much like outer space, our gut microbiome remains uncharted territory.
As medical students, we ran lab experiments on ourselves to see what kind of microbiota grew in our guts. We identified around half a dozen different types of bacteria using rudimentary culture methods. Since then we’ve used genomic DNA analysis to identify many more species.
We estimate that 3,000–4,000 different species of flora (bacteria) grow in your gut. Given the tremendous numbers of bacteria and possible permutations, the resulting “biological cosmos” in our guts is nearly endless and difficult to understand completely.
Now that we’ve established the challenge of understanding this environment, let’s begin our discussion of probiotics as a possible therapeutic modality.
Probiotics Therapy Potential
Using probiotics as therapy entails introducing good bacteria to the body to alter the existing balance of bacteria in the gut.
The bacteria in our gut are involved in a wide array of processes that can effect our health, including:
- Maintaining immune function
- Helping break down food into beneficial components
- Displacing harmful bacteria from the gut environment
- Maintaining the integrity of the digestive tract’s lining
- Involvement in complex hormone signaling
Probiotics present potential in many therapeutic realms, and we continue to study them for many benefits, such as:
- Reducing the risk of antibiotic-associated diarrhea
- Improving digestive capabilities
- Improving immune response
- Reducing serum cholesterol
- Reducing the risk of cancer
- Reducing inflammatory bowel disease symptoms
- Reducing allergy symptoms
But Does It Work?
Because gut bacteria have so much individual variability, it’s challenging to definitively document probiotics’ benefits. It’s also difficult to establish those benefits through randomized control trials, so the surrounding literature is weak.
However, when considering the risk vs. benefit ratio, taking probiotics is inexpensive and very safe. We’re not talking about chemotherapy or brain surgery. Therefore, I’m open-minded to probiotics.
My Take and Today’s Takeaways
When a patient asks me, “How do I know if I need a probiotic?” or “Should I take probiotics?” my answer is, “Let’s give it a shot.” We can try a relatively short three-month trial and assess for improvement in symptoms.
One brand I recommend is Garden of Life, which has high counts of a lot of different species. Selecting a probiotic is like buying a lottery ticket. A probiotic with a greater variety of strains improves the odds of picking a winning combination.
The potential to provide tremendous therapeutic benefits with a safe intervention is very exciting. This is a complex story — one we’re still writing. Stay tuned for updates.
From Barry Rotman, MD: My New Role at Banner Peak Health
When I was a young child in the 1960s, I wanted to be an astronaut because the Apollo program fascinated me. This phase passed, and I contemplated other professions such as lawyer, therapist, and public policy analyst.
As an undergraduate, I studied political economy before deciding to become a doctor. In medical school, I considered specialties such as psychiatry, ophthalmology, and family practice before choosing internal medicine.
As an internal medicine doctor, I’ve had a wonderful career with a meaningful, direct impact on my patients. A third of a century later, I’m still refining “what I want to be when I grow up.”
The intellectual construct of internal medicine involves acquiring medical knowledge across many disciplines to treat patients’ wide range of problems. After decades spent studying what others have discovered, I’m now more fascinated by exploring new approaches to medicine, and I have a theory about where to look for answers.
Given the economic structure of healthcare in our society, medical advances that involve pharmaceuticals, surgical techniques, or expensive diagnostic modalities are disproportionately supported in terms of research, money, and implementation in our system, leaving many areas underserved. To describe this phenomenon, I’ve coined the term “diagnostic desert,” analogous to the term “food desert,” which is the scarcity of grocery stores in neighborhoods of low socioeconomic status.
With no lucrative drug, surgery, or diagnostic procedure, vast areas of healthcare remain underserved. The result: a “diagnostic desert.” Anyone who has sought care for chronic pain, insomnia, or menopause (to name a few examples) knows the paucity of resources for high-quality care in these areas.
Fortunately, there are other routes for healthcare innovation, such as sports medicine and consumer wearables. Individuals and sports teams create a market for new products and techniques that generate novel solutions for healthcare outside of traditional medicine.
A prime example of this new technology is photoplethysmography (PPG). Millions of people wear PPG fitness devices that shine LED light below the surface of the skin. The light bounces against our blood vessels and sends reflected light back for analysis, providing information about cardiac status, pulmonary function, sleep quality, and the autonomic nervous system.
For example, the 5-gram Oura Ring I wear, paired with my smartphone, generates an enormous amount of physiological data about me. When I was a medical student in the 1980s, an entire room filled with multiple machines would have been required to generate a comparable amount of data. PPG technology has the potential to transform our understanding of the human body by allowing us to move from studying individuals for limited amounts of time to having millions of people continuously monitor their health data.
Paradoxically, as medical technology advances, we generate data faster than we can explain its meaning and translate the information into treatments. For example, millions of people wear Apple Watches that record every heartbeat and recognize those suggestive of atrial fibrillation, even without symptoms. This massive population-based screening provides a very different perspective on the illness than diagnosing individuals who seek medical care for symptoms of atrial fibrillation. This raises questions: Who needs further evaluation? What burden of atrial fibrillation requires treatment?
PPG technology also shifts the focus of medical discoveries from test tubes, animal labs, or academic centers to the interaction between patient and physician. Online educational tools support these devices, which are sold directly to consumers and provide people with actionable information about their health. However, I believe their maximum value stems from incorporating the information into the patient-physician relationship, further enhancing personalized healthcare. In fact, for certain conditions, these wearable products provide better insights than any available medical technique.
For example, it’s common knowledge that stress is bad for you. Healthcare providers constantly admonish patients to reduce their stress. However, you can’t manage what you don’t measure. For the last few years, consumer devices such as Whoop, Oura, and the Apple Watch have quantified the physiology of stress in real-time using heart rate variability (HRV) assessments.
As a 50-year athlete and a 34-year physician with 17 years of concierge medicine experience, I’m well suited for investigating this realm. I strive to learn many valuable techniques that can bring innovative and groundbreaking healthcare to Banner Peak Health.
I’ve assumed the title of “Chief Innovation Officer” to describe my new responsibilities. I’m tremendously excited about moving into this new role. I now know “what I want to do when I grow up!”
Please continue to follow the blog to learn more about my discoveries.
VO2 Max: The Diagnostic Crystal Ball
The heart is one of the most studied organs. A variety of diagnostic modalities can help gauge your risk of a heart attack.
The traditional standard is a stress test, which involves getting hooked up to wires while running on a treadmill on a progressively steep incline. A doctor or assistant monitors your heart’s electrical activity and blood pressure.
Unfortunately, this test will only detect a diseased coronary artery (lumen or pipe) with 70% obstruction.
A more sensitive test is a coronary artery calcium score, which uses an ultra-fast CT scan to examine calcium deposits in atherosclerotic deposits in blood vessels. It’s more sensitive than a stress test and can detect evidence of atherosclerosis before the lumen or pipe is obstructed.
Now, our practice leverages Cleerly. This test involves intravenous dye injected into the bloodstream. A CT scan performs a 3D X-ray study (coronary artery angiogram) of the coronary arteries, which is then analyzed with a proprietary AI-guided model.
This model detects plaque within the vessel wall and the lumen and differentiates between hard and soft plaque. Hard plaque involves calcium deposits, but soft plaque doesn’t, which is why coronary artery calcium tests miss soft plaque deposits.
We have many ways of discovering what’s wrong with the heart. But what are the signs of a healthy heart?
Diagnostic testing tells us how “bad” a disease state is or how well something prevents a disease state. We often find ourselves in a dichotomy of investigating how potentially diseased the organ is versus our ability to assess how optimally the organ can function.
How bad is bad? How well is well?
Both are relevant, but I want to focus on how to optimize your health and prevent as much disease as possible.
What Is VO2 Max?
VO2 max represents the maximum amount of volume of oxygen (O2 represents oxygen) your body uses per kilogram of weight in one minute. I think of it as a metric for integrating how well your entire cardiovascular system works.
VO2 max testing involves studying your physiologic response to a standardized graded progression of work output.
A good analogy is that of a car’s horsepower, which tells you how fast the car can go, etc. It’s a system-wide metric of capability.
Instead of horsepower, we’re measuring “humanpower.” VO2 captures:
- How well your lungs bring in oxygen
- How well your heart moves blood through your body
- How well your muscles contract
- How well your mitochondria perform the necessary biochemistry to create mechanical energy
VO2 max determines the entire system’s quality. It’s a valuable measurement because it covers the entire, integrated system rather than just one part of the body. It does much more than just measure the signs of a healthy heart.
Peter Attia’s ‘Outlive’ — The Prognostic Value of VO2 Max
In his most recent book, Outlive, Peter Attia summarizes the prognostic value of VO2 max. He compares the health benefits of physical conditioning as measured by VO2 max with the magnitude of risk associated with other risk factors, such as smoking and diabetes.
For example, a non-cigarette smoker is 40% healthier than a cigarette smoker in the same physical condition. Meanwhile, if someone in the lowest 25th percentile of physical health started training and improved their condition to the 50th percentile, they would decrease their mortality risk by 50%.
That’s right. Getting off the sofa is better for you than quitting smoking.
I take this as a mandate to do my best to maximize everyone’s physical conditioning. You don’t have to become a marathon runner to drastically improve your health.
How Do You Improve VO2 Max?
We used to recommend high-intensity interval training (HIIT). We now know there are additional stages of conditioning you need to train to optimize VO2 max.
Returning to the car metaphor, it’s like a gearbox. Each gear represents a physiologic system to be analyzed, understood, and optimized. All the gears need to work together seamlessly.
VO2 max does more than just measure the signs of a healthy heart. It represents the health of the whole package — heart, lungs, vascular system, and more. That’s why it’s so powerful and why we’re so excited to add it to our offerings.
Stay tuned for a deep dive, coming soon.
How to Be a Critical Reader of Medical Articles in the Lay Press
We’re officially in the throes of an “infodemic.” Every day, we’re inundated with more information than we can process about a variety of topics, especially medicine.
Why is this happening? One reason is that there exists a bias in medical literature reporting. Every individual and institution in the research process has the potential to overinflate their findings’ value, seeking to gain greater exposure from the press.
Researchers are also pressured to produce noteworthy results. Impressive studies endow prestige and enhance scientists’ and journalists’ careers. Because there’s so much at stake, there’s a tendency to mislead with less-than-accurate information.
Combine that with the press’s tendency to report overly optimistic or frightening statistics. Their goal is to get readers to click, read, and subscribe.
I want to give you the skills to navigate this infodemic of medical literature. Once you finish this post, you’ll be able to read critically and discern between relevant data and sensationalism.
5 Categories of Errors
I’ve identified five categories of common medical reporting errors.
1. We’re Not Animals
We have neither fur nor tails, yet many studies found in medical literature involve animals.
Animal experimentation is part of our research method. Only a minute percentage of discoveries from animal models ever impact human healthcare. Regardless, these studies often excite the press.
Example: Taurine is an amino acid shown to improve health and extend lifespan in mice. However, because of inherent physiological differences, there’s almost no chance this will ever be relevant to humans.
2. Data’s Numerical Representation Influences Its Emotional Impact
Data often tells more than one story, and journalists are storytellers. That can be a dangerous combination.
When the press presents the same data in multiple ways, people can interpret it differently, and the information can have various emotional effects. It can even influence public policy.
Example: The Women’s Health Initiative, which began in 1991, explored hormone replacement therapy (HRT) in postmenopausal women.
One randomized part of the study examined 16,000 women. In a subset study, 678 women — 385 from the HRT group and 293 from the placebo group — received a breast cancer diagnosis.
In 2005, the press reported those results as a 23.5% increased risk of breast cancer from HRT, a frightening finding. This statistic is true, breast cancer did occur at a rate of 0.42% per year in the drug group and 0.34% in the placebo group.
However, the results are more nuanced than that. Each year, for every 1,000 women in the trial, an average of 4.2 women on HRT could expect a breast cancer diagnosis, while an average of 3.4 women on the placebo could expect the same. There was a difference of only one woman per 1,000 each year between the two groups.
The press chose to express the data in a sensational way to entice readers to click on headlines and purchase newspapers. That single statistic changed women’s healthcare for over 20 years. Doctors and patients have been fearful of estrogen replacement therapy. As a result, an entire generation of postmenopausal women have been fearful of using a relatively safe treatment.
3. Man-Bites-Dog Journalism
Science is rarely about the result of any single study but the preponderance of evidence based on the compilation of many studies. However, when a touted study contrasts prevailing wisdom, it’s more likely to appear in the press. Journalists’ prerogative is to grab attention, and contrarian headlines accomplish that.
Example: In 2017, the Independent ran an article quoting one doctor who said, “Sugar benefits your brain health.”
This article expressed the opinions of a single doctor, who states that sugar may not be as harmful as we think it is.
It only became popular because it’s an assertion that goes against prevailing wisdom. In science and medicine, beware the contrarian.
4. Association Doesn’t Equal Causation
Human beings are not lab animals, particularly regarding our diet. It’s impossible to run randomized control trials on humans because we can’t control and measure everything test subjects eat against a control group.
Therefore, we rely on epidemiologic studies, which examine differences in people’s eating habits and try to correlate them with different health outcomes. Unfortunately, this form of study is notoriously susceptible to identifying associations that aren’t necessarily causal.
Example: For many years, red wine was believed to confer a health advantage. The consumption of red wine is associated with many other healthful behaviors, such as eating fresh fruits, vegetables, and healthier oils. Therefore, red wine is a confounder — associated with better health, but not causal.
Nutrition literature is particularly prone to miraculous attributions to certain foods.
5. Anecdotal Evidence Is Rarely Scientific Evidence
Anecdotal evidence may be exciting and compelling, but it’s rarely enough to inform or change the practice of medicine.
Example: The media is full of anecdotal evidence from people who successfully combatted their COVID-19 symptoms using ivermectin or azithromycin, both of which have been proven ineffective in randomized control trials.
Today’s Takeaways
Before you become too excited or too frightened by a medical article, remember the following:
- Humans are not animals.
- Be leery of data expressed as percent change rather than an absolute number.
- Beware the contrarian. Don’t take it at face value if something goes against all conventional thinking.
- Association does not equal causation.
- Sample size matters. Don’t extrapolate universal truths from single or small sets of unique events.
There are always exceptions to these rules. Every day, the media reports valid science, and every day, they sensationalize. By being an informed, discriminating reader, you’re better equipped to find the kernels of truth and stay above the fluff.
Our First Year Using an InBody Device (And What It Is)
An InBody machine provides body composition information, including fat weight, water weight, and dry lean mass (muscle, bone, and connective tissue). It allows for a more accurate description of a patient’s body composition than BMI.
This article will answer the question, “What is an InBody scan?” and explain what we’ve learned since acquiring our InBody device.
InBody at Banner Peak Health
We were excited to introduce our InBody device in January 2023.
What is an InBody scan? It’s a bioelectrical impedance analysis for determining what percent of a person is water weight, muscle weight, and fat weight.
A patient stands on the InBody device and holds an electrode in each hand. The device sends an imperceptible current across different axes generated from those four contact points.
The device calculates the resistance across each axis and diagnoses what percentage of the patient is water, fat, and muscle. It’s able to accomplish this due to a fundamental chemical difference between water and fat: water conducts electricity, while fat insulates.
Stepping on a scale doesn’t give us clinically vital information regarding the body’s composition. InBody does.
Our Biggest Insights
Anyone looking in a mirror or stepping on a scale can tell whether they’re overweight. When we started using our InBody scan, we weren’t surprised by the fat content results we saw. However, other results did surprise us.
Sometimes, patients who appeared healthy found out they weren’t as healthy as they thought. Their muscle mass was declining, and they were at risk for sarcopenia. (More on this later.)
Other patients who expected poor results because they were overweight had excellent muscle mass. Hidden in their bodies were real athletes!
We give credit where credit is due. InBody scans help us diagnose and treat every patient appropriately.
Muscle Mass Matters Most
You can’t tell someone’s muscle mass just by looking at them. That’s where InBody comes in handy.
Muscle mass predicts longevity and level of function in later adulthood (age 50+). If we identify and enhance muscle mass in middle age, we can improve the quality and duration of our lives.
It’s also imperative to diagnose and prevent sarcopenia — the decline in muscle mass associated with age. With InBody’s help, we can treat and correct sarcopenia more effectively.
Strength Training
When we discover a patient is at risk for sarcopenia, we recommend strength training and other regimens. For some, this means taking advantage of gym memberships or arranging sessions with a fitness instructor.
Some older patients may use wheelchairs but still need to practice strength training. We send Zoom links for exercises they can do while seated.
Protein Intake
Protein intake is also crucial for building muscle. The current recommended daily allowance (RDA) is 0.8g of protein per kilogram of body weight, according to the FDA. However, experts like Peter Attia recommend 2g per kilogram of body weight (2.5 times the RDA).
The RDA is the minimum amount necessary to stave off a disease state, while Peter Attia’s recommendation advocates maximizing your health state. I target somewhere between the two to enhance patients’ health.
Not all proteins are equal. For example:
- 1g of animal protein is not the same as 1g of vegetable protein.
- The ratio of amino acids in different proteins varies.
- Each type of protein has a different bioavailability.
If you’re not careful, you can exceed your recommended caloric intake. We’re exploring various supplement options as a means to avoid this.
We’re also looking into branched-chain amino acids, a potent form of amino acid supplementation that may preserve muscle mass. Because there is such a wide array of commercial products available, I’m uncomfortable making a pronouncement until I know more.
Tracking What Happens to Muscle Mass During Weight Loss
Successful weight loss involves expending more calories than you ingest. Ideally, we want fat to provide that excess energy, but we don’t always get what we want.
For most weight loss regimens, we expect to lose 75% of weight from fat and 25% from muscle mass. However, we’re finding through InBody scans that when patients use weight-loss medications like Ozempic and Mounjaro (which have GLP-receptor agonist activity), that ratio can be as high as 60% fat loss and 40% muscle loss.
For some patients, this is problematic or even dangerous. By monitoring muscle mass and recommending increased protein intake as well as strength training, we can mitigate the risk of these weight loss medications.
Today’s Takeaways
In addition to the traditional metrics of weight and blood pressure, we now also track muscle mass. InBody provides a more nuanced look into a vital health status.
At Banner Peak Health, we’re always excited to implement new technology that helps us gain insights into each patient’s health status.
So, what is an InBody scan? It’s one of the latest tools that allows us to provide state-of-the-art medical care. It has reinforced that preserving muscle mass is essential to living a long, healthy life.
Does a Meniscus Tear Need Surgery?
It was a warm fall afternoon, and I was running in the hills above Berkeley when I felt a sudden pain in my right knee. No negotiation possible; I had to stop running. Unfortunately, I still had to walk a few miles to my car, and that’s how my persistent pain started.
The pain persisted and I had to acknowledge that my knee wasn’t going to improve on its own. After a visit to an orthopedist and an MRI, I received my diagnosis: a degenerative meniscal tear in my right knee.
I had the same questions any patient would have in this position, including, “Does a meniscus tear need surgery?” Here’s what I’ve learned both from personal experience and medical literature.
What Is a Meniscus Tear?
The meniscus is a figure-eight-shaped fibrocartilaginous “washer” that cushions the knee between the femur (on top) and tibia (on bottom). Meniscus tears or injuries are common and result from either acute or degenerative mechanisms.
Acute injuries occur when a single force overwhelms the structural integrity of the joint, like when a 17-year-old soccer player gets slammed from the side. That acute force overloads the knee’s structural anatomy and damages the meniscus.
Degenerative injuries occur as a result of wear and tear over time. For example, in my case, I’d been running regularly for decades, and that repetitive force caused my meniscus to gradually wear down until it tore in 2005. I had a pothole inside my medial meniscus, which caused pain, low-level swelling, and walking impairment.
Does a Meniscus Tear Need Surgery? My Options
I discussed the options with my orthopedist and decided to try physical therapy. If my knee didn’t improve, we’d consider surgery.
I embarked on six to eight weeks of physical therapy, including exercises to strengthen my quadriceps and increase my hamstring flexibility. I also refrained from putting force on my knee by running.
Within two to three months, I was back to baseline function and could bike, hike, and run.
Don’t Shoot the Messenger… Listen to It
Medicine often falls into the cognitive trap of “shooting the messenger.” It’s an idiom from ancient Greece, when a messenger had to deliver bad news to a king and lost his life for his trouble.
In modern medicine, the injury is the messenger, not the beginning of the story. The meniscal tear communicated a problem. Why did the tear happen in the first place?
My orthopedist saw the injury as the problem and didn’t go upstream to explore what about my body, structurally or ergonomically, had created the injury.
So, I worked with a podiatrist and did a gait analysis. We modified an insole and created a lifelong physical therapy routine to strengthen my core and stabilize my leg.
I was relieved to heal without needing surgery. I heeded the message to try to build back better and avoid future injuries.
Take Two
Seventeen years later, while on vacation in Hawaii, I felt a low-level pain in my left knee. It was less severe this time, so foolishly, I continued to run for several weeks before addressing it.
After an evaluation with a sports medicine doctor and another MRI, I discovered I had another meniscal tear, this time in my left knee. However, this tear was complex. Instead of being a two-dimensional problem, part of the tissue had flipped up and occupied more of the joint space.
If my right knee had a small “pothole” in the meniscus that needed to heal, my left meniscus had the equivalent of a raised bump, like a pebble stuck between a foot and shoe.
This time I asked, “Does a meniscus tear need surgery if it’s complex?”
A Landmark Study
In 2013, the New England Journal of Medicine published a landmark study noting that arthroscopic partial medial meniscectomy (removing the damaged part of the meniscus) occurred in about 700,000 cases annually (at the time of the study), making it one of the most common orthopedic procedures performed.
My case matched perfectly with those in the study. The test population involved 35- to 36-year-olds with no underlying arthritis who had undergone a degenerative tear. Remarkably for a surgical study, the design included placebo controls. Half received the arthroscopic partial resection of part of their meniscus, and the other half underwent surgery with arthroscopy with no tissue removed.
The results showed that 12 months after surgery, there was no difference in functional capacity or pain between those who had received the real or sham surgery. This was a shocking result, demonstrating the body’s ability to heal from these types of injuries without any surgery.
The problem with partial meniscectomy has to do with the meniscus’s anatomy. Since it’s fibrocartilaginous, there’s little to no blood supply, so the part surgeons remove won’t grow back. The knee must continue to function with less of that figure-eight donut cushioning each impact between the femur and tibia. Over time, forces are applied to less of a cushion between the femur and tibia, increasing the forces applied directly to the bone and the risk of osteoarthritis.
Making My Choice
After considering the potential long-term complications of surgery and the randomized control trial’s results, I decided to give physical therapy a shot.
I wish it had gone as smoothly as it did in 2005, but there’s a difference between healing at 40 and healing at 60. The tears’ anatomies were also different, and the second, more complex tear posed a greater challenge.
I aggressively pursued physical therapy, and the fear of surgery and its attendant risk of osteoarthritis compelled me to remain diligent. I slowly regained function and reduced pain.
As of this writing, I still refrain from running. I can hike, bike, and backpack, but I modify my ergonomics.
What Was This Injury’s Message?
While working with a physical therapist, I learned that I had a reduction in right ankle flexion and tightness in my hamstrings. I’m now addressing the root causes of my left knee injury to prevent future issues.
Physical therapy is not just about regaining function after an injury. It’s about addressing why you had the injury and working to prevent future ones.
People undergoing physical therapy, and many doctors prescribing it, often miss that point. Emphasizing it will give people further incentive to do the hard work physical therapy requires.
Today’s Takeaways
- If you’re asking, “Does a meniscus tear need surgery?” after suffering a meniscus tear, the answer is, “Only as a last resort.” If all else fails and multiple surgeons recommend it, it’s a valid option. Until then, focus on physical therapy.
- Physical therapy reduces the risk of future injuries and helps correct the structural problems that led to the initial injury.
Take physical therapy seriously. Your knee’s life depends on it.