To the Editor:
In 2015, for the first time in nearly 25 years, life expectancy decreased in the United States.1 The decrease was small—from 78.2 to 78.1 years—but is nevertheless a cause for concern given recent studies2,3 showing adverse trends in mortality (although these studies were limited to whites). Understanding the components of changes in life expectancy, and how they differ across demographic groups, is an important first step toward identifying root causes and potential ameliorative interventions.
We abstracted data on deaths and population from the US National Vital Statistics System by age, cause-of-death, and race ethnicity for 2014 and 2015.4 We limited our analysis to non-Hispanic blacks and non-Hispanic whites because of longstanding concerns for black-white differences in life expectancy. We created abridged life tables and used Arriaga’s5 method for decomposing changes in life expectancy by age and cause-of-death. We selected International Classification of Disease, 10th edition codes (Figure) to capture leading causes of death among gender and race groups. We used Stata software (version 14) to analyze the data and do not present measures of precision because the mortality data are available for the entire population.
Among non-Hispanic men, life expectancy at birth decreased from 76.6 to 76.5 years for whites and from 72.7 to 72.4 for blacks. For non-Hispanic women, life expectancy decreased from 81.3 to 81.1 years for whites and remained essentially constant (78.5 years) for blacks. The largest absolute increases in age-adjusted death rates between 2014 and 2015 were for Alzheimer’s and cardiovascular disease among women, unintentional poisoning for men, and homicide for black men (eTable 1; http://links.lww.com/EDE/B202).
Among white women, increases in cardiovascular and Alzheimer’s disease accounted for 71% of the decrease in life expectancy (Figure). Alzheimer’s disease also made a notable (20%) contribution among white men, but the majority (50%) of the decline was due to unintentional poisoning, in addition to suicide (12%) and motor vehicle crashes (11%). For black men, however, increases in homicide accounted for nearly 60% of the life expectancy decrease, alongside contributions from unintentional poisoning (23%) and motor vehicle crashes (16%). Improvements in cancer survival kept life expectancy from decreasing further in all groups. Analysis by age group showed that the increase in mortality among the oldest group (85 and over) accounted for 49% of the decrease in life expectancy for white women, whereas mortality increases among those 15–44 accounted for 80% and 65% of the decrease for black and white men, respectively (eFigure 1 and eTable2; http://links.lww.com/EDE/B202).
The decline in US life expectancy resulted from a heterogeneous group of causes of death, and did not affect all demographic groups equally. Black men lost nearly twice as many years of life expectancy than did white men, and black women showed virtually no change in life expectancy.
The increase in cardiovascular disease is worrisome and consistent with other reports of stalling progress in mortality declines, but our estimates show that this primarily affected life expectancy among white women. Considerable attention has also focused on middle-aged whites who have experienced sustained increases in mortality, largely due to the rise in opioid overdose deaths.2,3 However, the rise in homicide, which disproportionately affects young black men, has received little attention. Although the homicide rate has shown impressive declines since peaking in the 1970s, the 2015 increase requires additional investigation.6 If this trend were sustained it could erode the substantial progress made in reducing the black-white life expectancy gap.7 On a more positive note, improvements in cancer survival kept life expectancy from decreasing by more than it otherwise would have.
Our analysis used the underlying cause-of-death and may underestimate the contribution of factors involved in multiple causes. Our findings demonstrate that paths to decreased life expectancy differ substantially by gender and race.
Jay S. Kaufman
Department of Epidemiology
Biostatistics & Occupational Health
Montreal, QC, Canada
Richard S. Cooper
Loyola University Chicago
1. Xu J, Murphy SL, Kochanek KD, Arias E. Mortality in the United States, 2015. NCHS Data Brief, 2016:no 267. 1–8.
2. Case A, Deaton A. Rising morbidity and mortality in midlife among white non-Hispanic Americans in the 21st
century. Proc Natl Acad Sci U S A. 2015;112:15078–15083.
3. Shiels MS, Chernyavskiy P, Anderson WF, et al. Trends in premature mortality in the USA by sex, race, and ethnicity from 1999 to 2014: an analysis of death certificate data. Lancet. 2017;389:1043–1054.
4. Centers for Disease Control and Prevention, National Center for Health Statistics. Underlying cause of death 1999–2015 on CDC WONDER online database, released December, 2016. Data are from the Multiple Cause of Death Files, 1999–2015, as compiled from data provided by the 57 vital statistics jurisdictions through the Vital Statistics Cooperative Program; December 2016. Available at: https://wonder.cdc.gov/
. Accessed 12 December 2016.
5. Arriaga EE. Ruzicka L, Wunsch G, Kane P. Changing trends in mortality decline during the last decades. In: Differential Mortality: Methodological Issues and Biosocial Factors. 1989:England: Clarendon Press Oxford; 105–129.
6. Rosenfeld R. Documenting and explaining the 2015 homicide rise: research directions. National Institute of Justice; 2016. NCJ 249895. Available at: https://www.ncjrs.gov/pdffiles1/nij/249895.pdf
. Accessed 14 December 2016.
7. Harper S, Lynch J, Burris S, Davey Smith G. Trends in the black-white life expectancy gap in the United States, 1983-2003. JAMA. 2007;297:1224–1232.