An increased prevalence of atherosclerosis has been shown among patients with hypopituitarism. The aim of the present study was to assess whether patients with hypopituitarism experience increased cardiovascular, in particular cerebrovascular, mortality. Retrospective cohort study of mortality, 1952-1992, in 344 patients, of whom 130 were female, receiving conventional hormone replacement for hypopituitarism following neurosurgery for pituitary tumours. The general population in the catchment area of southern Sweden from which the patients were recruited constituted the reference population. Expected mortality was obtained from cause, sex, calendar year, and 5-year age-specific death raise for the area. Increased mortality from cerebrovascular disease (standardized mortality ratio (SMR) 3.39; 95% CI 2.27-4.99) was the main contributor to the increased overall cardiovascular mortality (SMR 1.75; 95% CI 1.40-2.19). The increase in mortality from cardiac diseases was much smaller (SMR 1.41; 95% CI 1.04-1.88). The risk for cerebrovascular death was higher in women (SMR 4.91) than in men (SMR 2.64). The relative risk for cerebrovascular death was independent of the time interval since diagnosis of pituitary insufficiency, but was greater in subjects diagnosed at an earlier age (< 55 years). No increased mortality in malignant tumours was observed (SMR 0.95; 95% CI 0.60-1.48). The increased cerebrovascular mortality may be due to GH deficiency, or to long-term lack or inadequacy of substitution for other pituitary hormones. The observations that an early onset of pituitary insufficiency and female sex are predictors for a high risk for cerebrovascular mortality merit particular attention when treating this group of patients.