Obesity is a major cause of early death among women living in the south (Image: moodboard / Corbis)

In a reversal of earlier trends, life expectancy is declining among some groups of Americans. Worldwide, such declines are rare. They happened, for instance, after the HIV/AIDS crisis in Africa and the collapse of the Soviet Bloc. They signal a healthcare failure, say the authors.

Majid Ezzati, at the Harvard School of Public Health, and his colleagues wanted to examine health disparities in the US, so they looked at mortality rates by county between 1961 and 1999. For this period, overall US life expectancy increased from 67 to 74 years of age for men and from 74 to 80 years for women, and until the 1980s, disparities between regions was decreasing. Since then, the disparities have been increasing.

Average American life expectancy continued to go up over the four decades.


Researchers often argue that disparities are not a big problem, because they simply reflect the fact that while everyone’s health is improving, some are seeing more improvement than others. In the UK, for instance, that is the case.

Shorter lifespans

But the US results suggest something more troubling: at least part of the increase in disparity in the US is caused by an actual decrease in life expectancy.

Women in particular, especially those living in the south, were living shorter lives, with almost one in five seeing a statistically significant decline or stagnation in life expectancy. Smoking, obesity and high blood pressure appear to be the causes.

The researchers refer to the increase in death rates amongst some groups as “the reversal of fortunes”.

Ezzati argues that to get a true picture of the nation’s health, you have to see what’s happening to groups at the bottom. “A single number for a country as large and diverse as the US is just not enough,” he says.

Journal reference: PLoS Medicine, DOI: 10.1371/journal.pmed.0050066

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