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.