Factors related to orthostatic hypotension associated with tricyclic antidepressants.

A group of 45 depressed patients treated with imipramine hydrochloride were examined in an attempt to identify factors that might influence the risk of developing orthostatic hypotension. Although the literature suggests that age and/or heart disease influences the occurrence of orthostatic hypotension, these conclusions are controversial. To pursue this issue, a sample of older depressed patients, many with severe cardiovascular disease, was chosen. The incidence of orthostatic hypotension rose dramatically among those with severe heart disease. There was a significant association between symptomatic orthostatic hypotension and cardiac medication (p less than .01), and trends between orthostatic hypotension and both ejection fraction (p = .11) and baseline forearm resistance (p = .16). The sample is too small to permit determination of the relative independent importance of these variables or the contribution of specific cardiovascular drugs among these sicker cardiac patients.