Medical evaluation of persons with mental retardation referred for psychiatric assessment.

Many people with developmental disabilities and "challenging behaviors" present to primary care physicians, internists, or general psychiatrists for assessment and treatment. These clinicians seek to provide the comprehensive biopsychosocial assessment necessary for successful treatment, but may encounter interference from funding agencies. Epidemiologic data on medical comorbidity in persons with developmental disabilities with a primarily "behavioral" presentation may assist in facilitating these assessments. A total of 1135 people with mental retardation referred for mental health assessment were medically evaluated according to a two-step protocol which included a screening evaluation of all persons and expanded testing, depending on clinical status. The workup was considered complete when the person with either improving clinically or had a specific terminal diagnosis and was as comfortable as possible. Medical comorbidity was about double that of people referred for mental health assessment who do not have mental retardation. Common conditions presented in unusual ways, and less frequent conditions presented more often. The cost of the medical assessments was promptly recovered in a variety of savings to systems. Comprehensive medical assessment discloses increased medical comorbidity in persons with mental retardation referred for psychiatric evaluation. Comprehensive treatment based on the assessment findings appears to be associated with better clinical outcomes and cost savings to systems.