Medical comorbid diagnoses among adult psychiatric inpatients

Shortened life expectancy of people with mental disorders has been attributed to medical comorbidities, yet these conditions remain under-recognized and under-treated. This study characterizes the medical demands placed on inpatient psychiatric units to help guide medical assessment and management practices in these settings.

Medicaid claims records and clinician data were linked with hospital and regional data for individuals with a principal diagnosis of any mental disorder admitted to psychiatric inpatient units in New York State from 2012 to 2013. A modified Elixhauser Comorbidity Index (ECI) score was calculated for each unique individual (n = 14,458). Adjusted odds ratios (AORs) of having a medical comorbidity were calculated using logistic regression analyses.

74.9% of psychiatric inpatients had at least one medical comorbidity, including 57.5% of people ages 18-24. Higher rates of medical comorbidity were associated with older age, female gender, non-schizophrenia diagnoses, and engagement in care prior to hospitalization. Patients with medical comorbidities had lower odds (AOR 0.54; 99% CI 0.35-0.83) of being treated in hospitals with 100 or more total beds compared to smaller hospitals.

A high prevalence of common medical diagnoses among psychiatric inpatients underscores the importance of adequate detection and medical treatment of medical comorbidities in psychiatric inpatient settings.