The Molecular Biology of the Social Determinants of Health: Optimal Medical Therapy Can Make a Difference
A recent report from the National Academy of Sciences says “Medical care is estimated to account for only 10-20 percent of the modifiable contributors to healthy outcomes for a population. The other 80 to 90 percent are sometimes broadly called the social determinants of health.” This article from Health Affairs provides more context “Good health is not evenly distributed in the United States. Racial and ethnic minorities and those who live in socioeconomically disadvantaged circumstances are more likely to suffer from poor health compared to socioeconomically advantaged and white counterparts.” That might lead you to fatalistically believe that medicare can only influence 10% of health outcomes, but that would be wrong.
Stress is a key to understanding how social determinants of health can lead to physical and mental illness. If you are not sure of having food, shelter and the other necessities of life, that is incredibly stressful. Being surrounded by violence and shootings leads to adverse childhood experiences and post traumatic stress disorder that are almost the rule. These factors lead to the increased release of stress hormones epinephrine, norepinephrine, and cortisol. These alterations may persist due to change in gene regulation (epigenetics). Now we can understand some of the key ways that physical and mental illness are related. We can understand why disadvantaged people have more cardiovascular disease, depression, cancer, and shorter lives.
Look at the upper right corner of the diagram. It shows aldosterone activating the mineralocorticoid receptor (MR). We have extensively discussed the role of aldosterone in obesity and cardiovascular disease. Cortisol also activates the MR to produce those same effects and we can block that effect with spironolactone or eplerenone. Primary aldosteronism is a pure example of aldosterone increase that causes hypertension. This condition is associated with higher rates of cardovascular complications than would be expected from the blood pressure level. It is also associated with increased anxiety, depression, and decreased memory. It is all related. It is all about molecular biology.
Optimal medical therapy interferes with the molecular biology that causes chronic disease and aging. It protects cells and organs. I am all for reducing disadvantage and disparities based on economics. Disadvantage is a viscious cycle. Lack of financial resources leads to stress, mental illness, physical illness and dysfunction which are all barriers to improving one’s lot in life. I am all for increasing opportunity but we don’t seem to be making much progress on that. In the meantime, optimal medical therapy can prolong healthier lives at lower cost in these populations and extend the impact we can have for these patients.