REGIONAL CEREBRAL BLOOD-FLOW AND CEREBROVASCULAR RISK-FACTORS IN THE ELDERLY POPULATION

Regional cerebral blood flow (rCBF) was studied in 60 elderly persons (aged 65 to 84 years) recruited from a population-bated study, with si ngle photon emission computed tomography using technetium 99m-labeled hexamethylpropylene amine oxime. We investigated whether it is only ag e that affects rCBF or whether other factors can be indentified that e xplain this relationship. Using multiple linear regression analysis, i ncreasing age was significantly associated with rCBF decrease in parie tal, temporo-parietal, and temporal cortex, but not in frontal cortex. Adjustment with several risk factors for cerebrovascular disease, inc luding hypertension, history of myocardial infarction, factor VIIc, fa ctor VIIIc, cholesterol and HDL cholesterol, smoking, and diabetes mel litus had no influence on these relations. Conversely, the association between age and rCBF was no longer statistically significant after ad justment with fibrinogen and indicators of carotid atherosclerosis, in cluding intima-media wall thickness of the carotid artery and plaques in the carotid artery. Correction with local ratings of cortical atrop hy did not affect the relations between age and rCBF. The results sugg est that in the elderly population rCBF declines with age in posterior cortical areas and that these changes may well be explained by the pr esence of atherosclerosis. Reduced contractility of the vascular muscl e wall with increasing age resulting from atherosclerosis may be the u nderlying mechanism. (C) 1998 Elsevier Science Inc.