This column examines the major reasons for nonpsychiatric inpatient stays in the Medicaid mental health service user population. Data are from the Center for Medicare and Medicaid Services' State Medicaid Research Files. A total of ten states—Alabama, Arkansas, Delaware, Georgia, Kansas, Kentucky, New Hampshire, New Jersey, Vermont, and Wyoming—were included. The study group consisted of nonelderly Medicaid recipients who used mental health and substance abuse services in 1995. Individuals who were enrolled in both Medicaid and Medicare and those in managed care programs were excluded because of limited information about their service use. Additional details about the population and methodology have been published elsewhere (1).

Across the ten states, 374,442 mental health service users who met the above criteria were enrolled in Medicaid during 1995. Of this group, 17 percent had at least one inpatient stay of any kind. Twelve percent had at least one inpatient stay for a nonpsychiatric reason, accounting for 75,528 such stays. Results are shown in Figures 1 and 2. All diagnostic categories that accounted for at least 5 percent of stays are displayed. Categories that accounted for fewer than 5 percent of stays, V codes, and symptom-related codes are included in the "other" category.

In both age groups, pregnancy and childbirth was the most frequent reason for nonpsychiatric inpatient treatment for Medicaid mental health service users, which also is the most common reason for inpatient stays among all Medicaid enrollees. Among the mental health service users, stays for pregnancy and childbirth were not solely accounted for by enrollees with less severe disorders or with lower mental health service use. Pregnancy and childbirth was the most common category of nonpsychiatric inpatient stays for patients receiving treatment for substance use disorders and for major depression or affective psychosis, as well as for high-cost mental health service users (data not shown).

Efforts to increase integration of primary care and mental health care can improve health outcomes for all mental health service users with comorbid conditions. However, efforts targeted at pregnant women with mental illness appear to be particularly important.

Dr. Buck is associate director for organization and financing at the Center for Mental Health Services of the Substance Abuse and Mental Health Services Administration, 5600 Fishers Lane, Room 15-87, Rockville, Maryland 20857 (e-mail, jbuck@samhsa.gov). Ms. Miller is senior research leader at the MEDSTAT Group in Santa Barbara, California. Harold A. Pincus, M.D., and Terri L. Tanielian, M.A., are editors of this column.