NORMAL HUMAN AGING - FACTORS CONTRIBUTING TO CEREBRAL ATROPHY

Factors that accelerate rates of 'normal' age-related cerebral atrophi c and degenerative changes are important because they may predispose t o cognitive declines. To determine characteristic patterns of normal a ging, risk factors were correlated with serial neurological-neuropsych ological examinations, CT measures of progressive cerebral atrophy, lo cal tissue hypodensities, or perfusional declines. Both cross-sectiona l and longitudinal designs were utilized. Ninety-four cognitively and neurologically normal aging volunteers, 15 with a history of transient ischemic attacks (TIAs), were followed for mean intervals of 3.0+/-2. 1 years. Results indicated that: (1) after age 60, cerebral atrophy, p olio-and leuko-araiosis doubled and cerebral perfusion decreased, with marked individual variations; (2) risk factors independently accelera ting cerebral atrophy and cortico-subcortical perfusional declines inc luded TIAs, hypertension, smoking, hyperlipidemia, excessive alcohol c onsumption and male gender; (3) progressive leuko-araiosis correlated directly with cortical atrophy and cortical perfusional declines. We p osit that: (1) cerebral atrophy and degenerative changes result from n euronal shrinkage and/or loss, which are accelerated by TIAs, hyperten sion, smoking, hyperlipidemia, excessive alcohol consumption and male gender; (2) accelerated cerebral atrophic and degenerative changes ide ntified by neuroimaging should be considered as markers for depleted n euronal synaptic reserves, which predispose to cognitive declines. Int erventions available for controlling some of these risk factors includ e control of TIAs, hypertension, and hyperlipidemia, as well as tobacc o and alcohol withdrawal. (C) 1997 Elsevier Science B.V.