Living with Chronic Lung Disease and the Aggregation of Marginal Gains
At my medical center we see a lot of people who live with complicated lung diseases — diagnoses that have not just one cause or treatment, but multiple etiologies that are layered on top of one another. These complex diseases are challenging and can be frustrating as they may not have one simple medication or treatment. But that does not mean they are not treatable. So for treating these multifactorial health problems, I often invoke the principle of the aggregation of marginal gains.
To explain this principle I have to take you back to British Cycling. The British national team was horrible for decades, not winning medals and they were so bad that for years bike manufacturers did not want their bike to be the team bike. Then Sir Dave Brailsford took over at the helm of the team, and started to invoke the principle of marginal gains. Rather than just push harder and have the athletes train longer, they got into the science of every small aspect of their training to get them to the next place. Could the bike seat be more comfortable so they could push harder for longer? Could the pillows be better so they got a better night’s sleep in recovery? Could the timing or nutrient content of their food be improved to assist with fueling and post-race recovery? These types of principles to every little detail helped the cyclists ride a little better each and every week. As they trained smarter they got better, to the point of winning 8 gold medals, 4 silver medals and two bronze medals in the 2008 Beijing Olympics and dominating again in 2012. This also led Sir Brailsford to launch Team Sky, which went on to be the first multi-year dominant team at the Tour de France as the cycling world reeled and recovered from the doping era (Wiggins won in 2012, followed by From in 2013, 2015, 2016, and 2017 and then Geraint Thomas in 2018). James Clear, author of Atomic Habits, writes in more details about the marginal gains philosophy in his blog, and this idea is foundational to his book (a really good read — we recommend this a lot in our clinic). And as a side note, it is this idea that really has advanced pro cycling (see: the dominance of Team Jumbo Visma this past season) and professional sports today.
Okay, PG. So other than taking any chance you get to talk about bicycling, what does pro cycling have to do with our pulmonary clinic and treating chronic disease?
While some breathing problems have a specific solution (an inhaler that completely treats mild asthma, for example), others are issues that do not have a “simple fix,” and this often leads to disappointment and frustration. However, it’s important to realize that not having a simple fix (a curative pill or inhaler) does not mean that chronic diseases are not treatable. And this is where I like to apply the principle of the aggregation of marginal gains.
One example of this is in a disease called aspiration-related lung disease. There are actually several conditions that relate to chronic aspiration (where someone takes acid and material from their GI tract into their lungs), and they range from vocal cord dysfunction, reactive airways type disease like asthma, diffuse aspiration bronchiolitis (inflammation of the airways), bronchiectasis (basically a dilated scarring of the airways), and aspiration pneumonia, aspiration pneumonitis, and interstitial lung disease. (For more on this see this review in Chest.) What often makes this condition challenging is that people can experience silent aspiration, meaning may not sense heartburn or taste reflux, but develop an insidious cough or increased shortness of breath. It can be quite challenging to diagnose and treat, but often there are characteristic findings on a CT scan that, with other testing like pulmonary function testing, help make it more clear.
When patients have a condition associated with aspiration, often they are prescribed medications to help quell the inflammation of the lung disease (e.g., anti-reflux medications, and sometimes promotability medications or anti-inflammatory medications), and also given a set of lifestyle changes to help reduce the risk of aspiration. Those changes include: Avoiding eating within 3 hours of laying down to go to sleep at night, avoiding spicy or acid-provoking foods, and elevating the head of the bed to use gravity. The trick of it is, a person with these conditions may do these things and not feel instantly any better (because they didn’t have the symptoms of heartburn to begin with), so implementing changes like this requires discipline and investment in the idea that doing so will lead to improvement.
Another problem that we often see at our center here in Denver is a problem of a blunted hypoxic response, especially in people who live at higher altitude. This can happen in people with or without underlying lung disease. High altitude is defined 2400 m (8000 ft). People often talk about “thin air” at altitude. Although the percentage of oxygen in the environment is the same in the earth’s environment (21%), the issue is that at higher elevation there is lower partial pressure of oxygen molecules in the environment (for Physics nerds, this is Dalton’s Law), and this partial pressure is important for driving oxygen from our alveoli (air sacs in the lungs) into our bloodstream (Graham’s Law). This becomes a complicated issue to manage, and we often invoke a multidimensional approach. First, I advise people to get some training in with supplemental oxygen so that they can train their muscles to better extract and utilize oxygen (i.e., create more and create healthier mitochondria). To do this we need to train in an aerobic environment with adequate oxygen to get to the muscles. This is why endurance athletes train at Zone 2 base most of the time rather than doing anaerobic sprinting. You train your body to be efficient with using oxygen by training while using oxygen. Additionally, with some people we have had success with biofeedback training and respiratory muscle strength training and using personalized programs to work to improve the sensor issues involved in exercise hypoxemia that may be separate from underlying intrinsic lung disease.
Another problem we see is a loss of cardiovascular fitness and muscle strength, as people are unable to exercise due to issues with breathing, this can compound the problems and they lose their fitness. This means that for any level of exertion or exercise, the muscles are less efficient at extracting and using oxygen, so this actually compounds shortness of breath.
Another issue we often see is poor metabolic heath, which is associated with a myriad of conditions that cause or contribute to shortness of breath such as stiffness of the left side of the heart, hypertension, sleep apnea, and weight-related issues.
So in my clinic, in addition to making an accurate diagnosis and getting people the appropriate medical therapy, we also focus on the additional “little things,” that certainly can add up to helping people breathe and feel better. We may not be able to cure certain lung diseases (like idiopathic pulmonary fibrosis, emphysema, or pulmonary arterial hypertension), so we may not be able to return someone to how they felt 10 years ago before they had their illness. However, when we apply the principle of the aggregation of marginal gains, we see that often people are able to achieve a better quality of life than where they started. The little things matter: getting adequate and quality sleep matters, exercise matters, doing things to minimize reflux matters, eating healthy food to even reverse metabolic disease and its associated conditions matters. And in so doing, working on each of these aspects of health (each of which further break down into more little things), will lead to significant results.
As I go into November, I am looking at ways to apply these principles to my own life and health and fitness. What are the little things you could do in your life to start to work toward big results?
For more on what is chronic lung disease, here is a link that discusses a few, from asthma and COPD to bronchiectasis, cystic fibrosis, interstitial lung disease, and pulmonary hypertension.
For more on applying the principle of marginal gains to your life, I recommend:
Atomic Habits, by James Clear — Book about creating habits to effect real behavior change
Mastermind, by Richard Moore — Book about Dave Brailsford
