Medical Comorbidity in Elderly Psychiatric Inpatients George S. Zubenko, Louis J. Marino, Jr., Robert A. Sweet, Aicha Hind Rifai, Benoit H. Mulsant, and Rona E. Pasternak A multidisciplinao" diagnostic evaluation was per~brmed jor 868 older psychiatric inpatients during a 46-month interval. A total of 402 (46%) met DSM-III-R criteria for organic mental disorders, 329 (38%) had mood disorders, 90 (10%) had psychotic disorders, and 47 (5%) had other mental disorders or conditions. Concurrent medical problems were systematically assessed and classi~ted according to ICD-9-CM criteria. The patients sufJered from a mean of 5.6 +- 3.1 (SD) active medical problems (range 0-18). This level of medical comorbidio; was significantly greater than that of older psychiatric: outpatients and comparable to that of elderly inpatients in general medical hospitaL~. When the effects of age and education were controlled for, there were no significant differences in mean numbers qf medical problems among the four groups of psychiatric inpatients. An association of major depression with diseases of the digestive system was observed and may be related to peripheral autonomic dysregulation. © 1997 Socie~.' of Biological Psychiatry Key Words: Aging, mental health, inpatient geriatric psychiatry, medical illness, comorbidity BIoL PSYCHIATRY 1997;41:724--736 Introduction Considerable efforts to explore the interrelationships among psychiatric illness, medical comorbidity, functional disability, and mortality have focused on the elderly, where these issues are common and compelling from a clinical perspective (for reviews see Schulberg et al 1987: Alexopoulos et al 1989; Cole 1990; NIH Consensus Conference 1992; Caine et al 1993; Katz et al 1994). Mental illness and poor physical health each contribute to functional disability and premature death (Kay 1962; Post From the Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh. Pennsylvania. Address reprint requests to George S, Zubenko. MD. PhD. Western Psychiatric Institute and Clinic. Room E-1230, 3811 O'Hara Street. Pittsburgh, PA 15213. Received March 1I. 1996: revised July 5. 1996. 1962, 1972; Murphy 1983; Cole 1985; Baldwin and Jolley 1986; Murphy et al 1987; Parmelee et al 1992, 1995; Lyness et al 1993). The basis for the association of mental illness and poor physical health is likely to be complex, as illustrated by studies of depressive and anxiety syndromes, which are among the most common mental disorders of the elderly. Medical problems may contribute directly to the occurrence of depressive syndromes de novo (Schul- berg et al 1987: Hall et al 1978; Koranyi 1979; Winokur et al 1988) or, as stressful life events, may precipitate the exacerbation of a recurrent affective disorder (Murphy and Brown 1980). The poor health of depressed elders may limit the choice of particular treatment modalities for depression (Popkin et al 1985; Katz et al 1990; Katz 1993; Perel 1994). Even when adequate treatment is provided, comorbid medical burden is a predictor of poorer response © 1997 Society of Biological Psychiatry 0006-3223/97/$17.00 Pll S0006-3223( 96 )00337-X