Disease incidence and mortality among older Americans and Europeans

Abstract

Recent research has shown a widening gap in life expectancy at age 50 between the United States and Europe as well as large differences in the prevalence of diseases at older ages. Little is known about the processes determining international differences in the prevalence of chronic diseases. Higher prevalence of disease could result from either higher incidence or longer disease-specific survival. This article uses comparable longitudinal data from 2004 and 2006 for populations aged 50 to 79 from the United States and from a selected group of European countries to examine age-specific differences in prevalence and incidence of heart disease, stroke, lung disease, diabetes, hypertension, and cancer as well as mortality associated with each disease. Not surprisingly, we find that Americans have higher disease prevalence. For heart disease, diabetes, and cancer, incidence is lower in Europe when we control for sociodemographic and health behavior differences in risk, and these differences explain much of the prevalence gap at older ages. On the other hand, incidence is higher in Europe for lung disease and not different between Europe and the United States for hypertension and stroke. Our findings do not suggest a survival advantage conditional on disease in Europe compared with the United States. Therefore, the origin of the higher disease prevalence at older ages in the United States is to be found in higher prevalence earlier in the life course and, for some conditions, higher incidence between ages 50 and 79.

Fig. 1

Comparison of survey probabilities of dying (₂q_x) and HMD life table probabilities of dying (₂q_x) 2004 for U.S. and five European countries. Curve of survey probabilities of dying are smoothed using a lowess filter and are weighted using sampling weights. SHARE includes Denmark, France, Italy, the Netherlands, and Spain

Fig. 2

Prevalence of disease in Europe and the United States by age in 2004. Prevalence by age and region at Wave 1 are computed using sample weights. A lowess filter is used to smooth the prevalence rates obtained

Fig. 3

Counterfactual simulation of prevalence by age estimated by varying incidence rates. We project prevalence by age starting with initial prevalence from each country and then apply incidence and survival rates keeping characteristics constant. The HRS scenario uses initial prevalence, incidence, and survival rates from the HRS, with average American characteristics. The SHARE-incidence scenario uses U.S. initial prevalence and survival rates but applies SHARE incidence rates evaluated at average characteristics from the United States. Finally, the SHARE scenario is analogous to the HRS scenario for Europeans. Incidence rates and survival rates are weighted. Aggregate baseline survival rates are also weighted to match period life tables

Fig. 4

Counterfactual simulation of prevalence by age estimated by varying survival rates. We project prevalence by age starting with initial prevalence from each country and then apply incidence and survival rates, keeping characteristics constant. The HRS scenario uses initial prevalence, incidence, and survival rates from the HRS, with average American characteristics. The SHARE-survival scenario uses U.S. initial prevalence and incidence rates but applies SHARE survival rates evaluated at average characteristics from the United States. Finally, the SHARE scenario is analogous to the HRS scenario for Europeans. Incidence rates and survival rates are weighted. Aggregate survival rates are also weighted to match period life tables

Fig. 5

Counterfactual simulation of prevalence by age estimated by varying initial prevalence rates. We project prevalence by age starting with initial prevalence from each country and then apply incidence and survival rates keeping characteristics constant. The HRS scenario uses initial prevalence, incidence, and survival rates from the HRS, with average American characteristics. The SHARE-prevalence scenario uses SHARE initial prevalence but applies HRS incidence and survival rates evaluated at average characteristics from the United States. Finally, the SHARE scenario is analogous to the HRS scenario for Europeans. Incidence rates and survival rates are weighted. Aggregate baseline survival rates are also weighted to match period life tables