Diagnostic patterns in hospital use by an urban homeless population.

Because patterns of disease and health care system usage by the homeless constitute a neglected area of research in the medical literature, we undertook a retrospective analysis of inpatient records on medically indigent adults, controlling for housing status, to add to the growing body of research in the area of homeless health care. Data on all 4,243 indigent patients admitted over 2 fiscal years (1985 and 1986) under the county medical services program of San Diego County, California, revealed 5.3% (226) to be homeless. The commonest major diagnostic category among the homeless discharges was "diseases and disorders of the skin, subcutaneous tissue, and breast," constituting 21.2% as compared with only 8.7% of the discharge diagnoses for housed indigent persons. Within this major diagnostic category, the predominant diagnosis-related group was cellulitis, accounting for 12.8% of diagnoses in the homeless and only 4.0% of discharge diagnoses in other medically indigent persons. A homeless housing status was also correlated with a higher percentage of discharges with the major diagnostic category of "substance use and substance-induced organic mental disorders" but was negatively correlated with that of "diseases and disorders of the circulatory system."