ORTHOSTASIS IN ALZHEIMER-DISEASE - A RETROSPECTIVE ANALYSIS

Vitiello et al. (1993) recently reported statistically significant dec reases in systolic blood pressure upon standing in patients with Alzhe imer disease (AD) (n = 60) as compared with healthy elderly controls ( n = 20), which would suggest a possible autonomic dysfunction associat ed with AD. To investigate this issue, we conducted a retrospective an alysis of blood pressures and heart rates of 31 patients 55-85 years o f age (mean 69.6) who met National Institute of Neurological and Commu nicative Disorders and Stroke/Alzheimer Disease and Related Disorders Association criteria for probable AD. The patients were selected from a pool of placebo-treated patients with AD in five inpatient phase I c linical trials. All patients met rigorous entrance criteria and thus w ere in excellent physical health except for AD, Blood pressure and pul se were assessed after 3-5 min of lying down and after 1-3 min of stan ding. Systolic and diastolic blood pressures showed decreases upon sta nding of 12 mm Hg (8.6%) and 6 mm Hg (8.2%), respectively, on day 1 an d decreases of 10 mm Hg (7.6%) and 4 mm Hg (5.7%), respectively, on da y 7 of hospitalization (p < 0.05). Pulse rates increased upon standing by 17% and 13% on days 1 and 7, respectively (p < 0.05). Our data sup port the finding of Vitiello et al. of significant postural decreases in systolic blood pressure in patients with AD. Well-controlled, prosp ective studies of orthostasis in AD and healthy elderly subjects shoul d be conducted to determine its prevalence in both populations and to determine whether the orthostatic changes seen in AD differ from those in normal aging.