Impact of ongoing primary care intervention on long term outcomes in uninsured and insured patients with depression

BACKGROUND AND OBJECTIVES. To assess the differential impact of an ongoing primary care depression intervention on uninsured and insured patients' outcomes 12, 18, and 24 months following baseline. RESEARCH DESIGN. Quasi-experimental longitudinal study of insured and uninsured patients with depression receiving treatment from 12 practices randomized to enhanced (intervention) and usual care study conditions. SUBJECTS. In 1996 to 1997, 383 nonelderly patients with depression (290 insured, 93 uninsured) were enrolled and followed for 24 months. MEASURES. Mental-health-related-quality-of life (MHQOL) was assessed at each follow-up using the SF-36 Mental Component Summary scale. Presence of major depressive episode was assessed at 24-month follow-up with the Composite International Diagnostic Interview. RESULTS. Uninsured enhanced-care patients had significantly better MHQOL outcomes at 24 months than uninsured usual care patients (40.6 vs. 32.7, respectively; P = 0.01). The intervention had no significant impact on insured patients' MHQOL outcomes at any follow-up interval. Among patients receiving usual care, the uninsured compared with the insured had significantly poorer MHQOL outcomes (32.7 vs. 40.7, respectively; P = 0.002) and significantly increased probability of experiencing a major depressive episode (40.6% vs. 19.8%, respectively; P = 0.04) at 24 months. No such disparities were observed between uninsured and insured patients receiving enhanced care. CONCLUSIONS. The ongoing intervention significantly improved quality-of-life outcomes in uninsured patients at 24 months. If the intervention's impact on MHQOL can be confirmed and proved cost-effective in larger uninsured patient populations, clinicians serving the uninsured may want to consider implementing the study's intervention.