75.6 years in 2007, the equivalent of 2.1 years per decade. While this is a significant achievement, it is less than the average increase for the other 21 countries examined for this study. Similarly, between 1980 and 2007, life expectancy at birth for U.S. women increased 3.3 years from 77.5 to 80.8 years, only slightly more than 60 percent of what was achieved, on average, in the same period in the other 21 countries examined. Among high-income countries that have recorded reductions in adult mortality at advanced ages, the Netherlands and Denmark stand out as the only other two countries that have recently underachieved. For both men and women, the divergence of experience between the United States and the other countries examined is clear both before and after age 50, although it is starker for women than for men. However, because 94–96 percent of newborns in high-income countries now survive to age 50, variation in life expectancy at birth is dominated by what happens over age 50, and the panel therefore chose to concentrate on mortality in this older age group.
The panel undertook a careful examination of cause-of-death statistics to see whether specific causes of death could account for the low level of life expectancy in the United States and were associated with improvements in life expectancy in vanguard countries. Comparative analyses of this sort are complicated by issues of variation in coding practices across countries and over time. Nevertheless, it does appear that higher mortality rates for lung cancer and respiratory diseases in the United States, Denmark, and the Netherlands are an important part of the story of recent trends. About half the gap between the United States and the countries with the highest life expectancies results from differences in mortality due to heart disease, so this condition should be a focus of efforts to bring U.S. life expectancy in line with that of the exemplar countries. Other conditions that account for the poor performance of U.S. women in particular include cerebrovascular conditions (primarily stroke), diabetes, and mental disorders.
The panel examined a number of possible risk factors and considered how differentials among countries in exposure to these risk factors might account for observed disparities in levels of and improvements in life expectancy. For some factors, comparable cross-country data exist on the current levels of risk, while for others, surprisingly little direct evidence can be brought to bear. The fluid nature of the relationship between mortality and some of the major risk factors also complicated the panel’s work. For example, the epidemiological literature still reflects considerable differences of opinion with respect to the magnitude of the relationship between obesity and mortality.
The panel’s strategy was to try to establish the strength of the evidence for a number of the most commonly proffered explanations of why the