Comorbidity of five chronic health conditions in elderly community residents: Determinants and impact on mortality

Background. Comorbidity is common in elderly persons. Its extent, correlate s, and life-threatening impact in representative community residents are un clear. Methods. Self-reported information of physician-diagnosed coronary artery d isease (CAD), cerebrovascular disease (CVD, diabetes, and cancer was obtain ed annually between 1986-87 and 1992-93, and hypertension was obtained trie nnially from the participants of the Duke Established Populations for Epide miologic Studies of the Elderly, a stratified multistage sample of 4126 Bla ck and White community residents aged 65-100, living in a five-county area of North Carolina. Date of death was obtained from death certificates ident ified through search of the National Death Index. Statistical procedures in cluded descriptive statistics, logistic regression, and survival analysis. Results. Of this sample, 57% reported hypertension, 20% diabetes, 15% CAD, 9% cancer, and 9% CVD; 29% reported none of these conditions, whereas 29% r eported two or more. Demographic characteristics were not related to comorb idity with CVD or cancer. Increased education tended to be protective. The effect of age, gender, and race varied with condition. At baseline there wa s substantial comorbidity among hypertension, CAD, CVD, and diabetes, but n ot with cancer. Hypertension, CVD, and diabetes were risk factors for CAD, whereas diabetes was a risk factor for CVD. After controlling for demograph ic characteristics, all health conditions except hypertension were predicti ve of B-year mortality, as was the presence of comorbidity. Conclusion. We found significant comorbidity in older persons who have hype rtension, CAD, CVD, or diabetes; particular risk of developing comorbidity, particularly CAD, among those with hypertension, CVD, and diabetes; and ri sk of CVD in those with diabetes. With the exception of hypertension, these conditions, and comorbidity per se, are life-threatening.