Clinical Diagnoses Before Age 75 and Men's Survival to Their 85th Birthday: The Manitoba Follow-up Study

Abstract

Of all Canadian and American men who live to age 75 years, about half can expect to live to age 85. Our objective is to examine how clinical diagnoses made before age 75 relate to a man's survival to age 85 years. Since 1948, a cohort of 3,983 young men (mean age of 31 years at entry) has been followed with routine contact and medical examinations to prospectively document incident disease. Over 62 years of follow-up, 2,414 of the cohort lived to celebrate their 75th birthday. Of these survivors, 1,060 (44%) died before their 85th birthday. Cox proportional hazard models were used to examine the effects of ischemic heart disease, cancer, cerebrovascular disease, diabetes mellitus, peripheral arterial disease, and chronic obstructive pulmonary disease on all-cause mortality between age 75 and 85 years. Modeled as six binary risk factors at age 75 years, all were significantly (p < .01) and independently related to 10-year mortality. Multivariate risk ratios ranged from 1.36 to 1.46 except for chronic obstructive pulmonary disease with a risk ratio of 1.85 (95% CI: 1.38, 2.49). The cumulative 10-year probability of survival from age 75 to 85 among men with none of these diagnoses was 63%, 52% for any one diagnosis, 39% for two diagnoses, and 22% for three or more diagnoses. Joint independence of these six common clinical diagnoses implies that each is important and their effects on mortality are cumulative.