Hypertension and Vascular Dementia*t

Postmortem surveys on patients treated for chronic hypertension often fail to demonstrate significant vessel changes. Nevertheless, hypertensive alterations in the brain can include infarcts and hemorrhages. Autopsies in a primary care hospital have shown that hypertension can affect arteries, arterioles, and capillaries in various patterns and degrees in the brain. These vascular lesions may be associated with large and small infarcts and hemorrhages in isolated or diffuse patterns. W idespread cerebral edem a can occur with rapidly progressive hypertension. Atherosclerosis, arterial and arteriolar fibrinoid necrosis, and micro-aneurysms may be observed. Chronic hypertensive encephalopathy causes vascular dem entia and can be associated w ith subcortical arterial and arteriolar leukoencephalopathy, leukoaraiosis and/or B insw anger’s disease. Epidem iologic evaluations based on com plete autopsy studies need to be correlated with compliance of therapy, appropriate diagnosis of hypertension, and its long-term effects on the nervous system. Although persistent poorly controlled hypertension is known to damage the brain both acutely and chronically, the effects of interm ittent hypertension rem ain to be defined. Hypertensive Strokes Hypertension is a common diagnosis and affects at least 60 m illion Am eri­ cans.12 D espite the advances in diagnosis and treatm ent of hypertension, postmor­ tem changes consistent with hyperten­ * Presented in part at the Spring meeting (May, 1991) of the Association of Clinical Scientists, Salt Lake City, UT. $ Medical students at UMKC School of Medicine, t Send reprint requests to Joseph C. Parker, Jr., M.D., University of Missouri-Kansas City, Truman Medical Center, Department of Pathology, 2301 Holmes Street, Kansas City, MO 64108. sion continue to be seen. Hypertension can cause various changes in arterial ves­ sels, depend ing on their size and the duration of the elevated blood pressure. In larger arteries, hypertrophy of smooth muscle and damaged elastic fibers with eventual fibrous rep lacem ent of th e ir walls leads to rig id ity and dilatation. In sm aller a rte rie s , in tim ai th ic k e n ­ ing may be present. Arterioles may dis­ play lipohyalinosis.4 Acute hypertensive cerebral changes include encephalopathy, fibrinoid arte­ rial necrosis, and intraparenchymal hem ­