Gap in Life Expectancy Between US Blacks and Whites Is Narrowing

March 20, 2007 (Montreal, QC) - The gap in life expectancy between black and white populations in the US has declined in recent years because of fewer deaths in blacks due to homicide, HIV, and unintentional injuries, and, among females, heart disease, a new study shows [1]. But further narrowing of the gap will require concerted efforts in public health to address the major causes of the remaining gap, the leading one of which is heart disease, the authors conclude.

The study, published in the March 21, 2007 issue of the Journal of the American Medical Association, was conducted by a group led by Dr Sam Harper (McGill University, Montreal, QC), who analyzed data from the US National Vital Statistics System to try to determine the causes behind trends in mortality differences between blacks and whites.

Harper commented to heart wire : "We found good news and less good news. Over the past decade we have made some progress in narrowing the gap in mortality between blacks and whites, but there is still a long way to go. The gap between blacks and whites remains large--at 6.3 years for males and 4.5 years for females, with cardiovascular disease accounting for about 30% of the difference in men and 40% in women."

Harper pointed out cardiovascular disease is the key issue that needs to be addressed in the black population. "Hypertension is a much greater problem in blacks than in whites, and obesity is a particular problem in black women. These both contribute to the cardiovascular mortality gap between blacks and whites. This gap is not going to close without some additional effort. In addition, while deaths from cardiovascular disease are declining in all groups, the pace of decline seems to be slowest in older black men. We must redouble our efforts to target the major risk factors in the black population, and to do this, we must improve their access to healthcare," he stressed.

He explained that in general over the past century the gap in mortality between blacks and whites has been declining, but there have been a few "blips" where the gap has increased, which occurred during the 1960s and again in the 1980s. "The causes of these blips are likely to be different. For example, the increase in the gap in the 1980s is believed to have been partly due to deaths from HIV, which obviously wasn't the issue in the 1960s," he added.

The authors report that since the early 1990s, the mortality gap has narrowed again--from 7.1 years in 1993 to 5.3 years in 2003. "In the 1990s, we did see some narrowing of the mortality gap, probably because of a reduction in deaths from HIV and homicide in younger black men. But these trends are now leveling out, and there remains a large disparity between blacks and whites," Harper told heart wire .

Life expectancy (from birth) in US according to sex and race: Figures from 2003

Harper pointed out that socioeconomic factors were clearly a major contributor to the mortality gap between blacks and whites, with access to healthcare one of the key issues here. "While race may also play a part, this is by no means certain. For example, although blacks have more hypertension than whites, if it were treated appropriately this difference might no longer be seen. If everything else were equal apart from their race, this mortality gap might not exist," he said.

Three main causes: HIV, homicide, and heart disease

The key results from the study showed that among females, the black-white life-expectancy gap increased by 0.5 years in the period 1983-1993, primarily due to increased mortality from HIV. The gap among males increased by two years in the same period, principally because of increased death rates from HIV, homicide, and heart disease.

Between 1993 and 2003, the female gap decreased by one year (from 5.5 to 4.5 years), driven by relative mortality improvement among blacks in heart disease, homicide, and unintentional injuries. The decline in the life-expectancy gap during this period was larger among males, declining by 25% (from 8.44 to 6.33 years), nearly all of which was due to fewer deaths among young to middle-aged black men from homicide, HIV, and unintentional injuries. But lack of improvement in heart disease in older black men kept the gap from narrowing further.

The authors note that the increase in homicide occurred primarily in young black men during the mid-1980s and appears to have been linked to the spread of crack-cocaine markets, which came under more control in the 1990s. But they add: "Homicide remains a leading contributor to the black-white life-expectancy gap among males, and strategies to reduce homicide mortality among blacks are urgently needed."

HIV is another culprit that contributed to the widening of the black-white life-expectancy gap in the 1980s but made a substantial contribution to narrowing the gap since 1993, Harper et al write. The steep declines in HIV mortality were due to the introduction of highly active antiretroviral therapy, but despite this success, HIV mortality remains a leading contributor to the remaining black-white gap, and the delivery of proven primary-prevention interventions, cost-effective voluntary testing, and expanded access to HIV treatments, especially for minorities, should remain high public-health priorities, they add.

However, cardiovascular-related diseases remain the leading cause of black-white differences in life expectancy, with cardiovascular causes and diabetes together accounting for 35% of the gap in males and 52% in females, the authors report. "Future efforts to reduce the black-white gap should be aimed at reducing existing inequalities in cardiovascular risk factors, particularly hypertension, and improving access to effective treatments for existing disease that remain underused," they conclude.

1. Harper S, Lynch J, Burris S, and Davey Smith G. Trends in the black-white life expectancy gap in the United States, 1983-2003. JAMA 2007; 297:1224-1232.

The complete contents of Heart wire , a professional news service of WebMD, can be found at www.theheart.org, a Web site for cardiovascular healthcare professionals.

Heartwire from Medscape © 2007  Medscape

Cite this: Sue Hughes. Gap in Life Expectancy Between US Blacks and Whites Is Narrowing - Medscape - Mar 20, 2007.