Income and Life Expectancy

Stands to reason that wealthier individuals have better access to health care and therefore might live longer.  Research in the Journal of the American Medical Association explores the subject.  (JAMA Article)  The researchers examined changes in life expectancy from 1999 through 2014 and looked at the association with income over that period.  Income data came primarily from tax records and life expectancy was calculated by traditional methods, but the association with income was probed with a two-year lag and income was frozen at age 61, due to declines from retirement after that age.  The researchers also looked at socio-demographic factors, health behaviors and access to health care.  Men in the bottom 1% of income at age 40 had a life expectancy of 72.7 years.  Those in the top 1% of income had life expectancy of age 87.3.  Women in the bottom 1% at age 40 could expect to live 78.8 years, while those in the top 1% had a live expectancy of 88.9 years.  Women had longer life expectancies at all income levels but the gap was narrower for higher income groups.  While income was clearly associated with life expectancy, the relationship was concave, that is, at higher income levels, every additional dollar of income didn’t do much for a longer life.  In addition, over the period used for the study, those in higher income groups showed a greater gain in life expectancy than did individuals in lower income categories.  And while there is significant geographic variation in life expectancy, that is largely confined to lower income groups, with noticeably less geographic variation among higher income percentiles.  Nevada, Indiana and Oklahoma had the lowest life expectancy for lower income people, while the highest was in California, New York and Vermont.  For high income individuals Nevada, Hawaii and Oklahoma had the lowest life expectancy and Utah, DC and Vermont the greatest.

As you would expect, smoking and obesity rates were negatively associated with life expectancy for lower income individuals, while health insurance status and health spending were not associated with life expectancy, nor was the level of income inequality.   The strongest message from the analysis is that health behaviors, not sociological factors, are most strongly correlated with life expectancy, and lower income people tend to have worse health behaviors.  The real link here is likely educational.  People who are better educated tend to have higher incomes, and people who are better educated tend to make better decisions in all areas of their lives.