Does psychiatric comorbidity increase the length of stay in general hospitals?

Several studies reported that in non-psychiatric hospital departments menta lly ill patients have a longer length of hospital stay than mentally well. But their methods are often limited because other predictors of length of s tay were excluded from statistical analyses. Using the Clinical Interview S chedule, research psychiatrists interviewed 993 patients of medical, surgic al, gynecological, and rehabilitation departments in Austria. Using several multiple regression analyses, the influence of psychiatric comorbidity and other variables on length of stay was analyzed. 32.2% of all patients suff ered from psychiatric morbidity. Of all psychiatric cases, 6.2% received mo re than one psychiatric diagnosis. Presence of psychiatric disorders, age, a diagnosis of neoplasms, number of all somatic diagnoses, and the number o f previous non-psychiatric hospital admissions predicted length of stay. Pa tients with dementia, with substance abuse disorders, and with alcohol- and drug-related psychiatric disorders showed a significantly increased length of stay, while other psychiatric diagnoses did not differ from the mentall y well. Even after controlling for confounding variables, dementia and subs tance related diagnoses increase the length of hospital stay. It is importa nt to investigate interventions for early recognition and treatment of thes e disorders. (C) 2001 Elsevier Science Inc. All rights reserved.