U.S. life expectancy declined in 2015 for the first time in more than two decades, according to a National Center for Health Statistics study released last week. The decline of 0.1 percent was ever so slight ― life expectancy at birth was 78.8 years in 2015, compared with 78.9 years in 2014. However, this reversal of a long-time upward trend makes these results significant.
While many researchers are scratching their dumbfounded heads in utter astonishment, I hypothesize the decline in life expectancy is partly due to the decrease in the primary care physician supply. Studies have shown the ratio of primary care physicians per 10,000 people inversely correlates with overall mortality rate. It is a well-known and reproducible statistical relationship that holds true throughout the world. In the U.S., increasing by one primary care physician per 10,000 population, decreases mortality by 5.3%, ultimately avoiding 127,617 deaths per year.
Headlines last week highlighted how much these unexpected results left the researchers baffled. Jiaquan Xu, a lead author of the study told The Washington Post, “This is unusual, and we don’t know what happened…so many leading causes of death increased.” Age-adjusted death rates went up by 1.2 percent, from 724.6 deaths per 100,000 people in 2014 to 733.1 in 2015. Death rates increased for eight of the ten leading causes of death, including heart disease, chronic respiratory illness, unintentional injuries, stroke, Alzheimer’s disease, diabetes, renal disease and suicide. Differences in mortality were most prevalent in poorer communities, where smoking, obesity, unhealthy diets, and lack of exercise are ubiquitous.