Comorbidity of other chronic age-dependent diseases in dementia

This study compares the prevalence rates of 5 common age-dependent diseases in non-demented and demented subjects. Control and dementia populations were approximately age-matched and their numbers also approximated. Prevalence rates for hypertension, myocardial infarction (MI), stroke, cancer and diabetes were determined. The rates of two or more coexisting diseases in the same patient were also compared. Two populations were studied: one was designated the autopsy series, and the other the hospital series. In the autopsy series, the rate of cardiomegaly/hypertension was 1.3 times higher in the control than in the dementia population, and for MI it was 1.7 times higher in the former than in the latter. The rate for stroke was higher in the control group by only a factor of 1.1, for cancer by only a factor of 1.2, and for diabetes the rates were almost identical in the two populations. The rate differences were statistically significant only with respect to cardiomegaly and MI. When the non-vascular and vascular dementias were compared, the rates in the latter were higher by only a factor of 1.3 for cardiomegaly, stroke, cancer and diabetes; for MIs, the rates were about the same in the two dementia categories. The data for two or more coexisting diseases were almost identical in control and dementia autopsy populations. In the hospital series, the hypertension rate was 1.6 times higher in the control than in the Alzheimer's disease (AD) group; for MI, the control group was higher by a factor of 1.5.(ABSTRACT TRUNCATED AT 250 WORDS)