Integrating primary medical care with addiction treatment - A randomized controlled trial

Context The prevalence of medical disorders is high among substance abuse p atients, yet medical services are seldom provided in coordination with subs tance abuse treatment. Objective To examine differences in treatment outcomes and costs between in tegrated and independent models of medical and substance abuse care as well as the effect of integrated care in a subgroup of patients with substance abuse-related medical conditions (SAMCs). Design Randomized controlled trial conducted between April 1997 and Decembe r 1998 Setting and Patients Adult men and women (n=592) who were admitted to a lar ge health maintenance organization chemical dependency program in Sacrament o, Calif. Interventions Patients were randomly assigned to receive treatment through an integrated model, in which primary health care was included within the a ddiction treatment program (n=285), or an independent treatment-as-usual mo del, in which primary care and substance abuse treatment were provided sepa rately (n=307). Both programs were group based and lasted 8 weeks, with 10 months of aftercare available. Main Outcome Measures Abstinence outcomes, treatment utilization, and costs 6 months after randomization. Results Both groups showed improvement on all drug and alcohol measures. ov erall, there were no differences in total abstinence rates between the inte grated care and independent care groups (68% vs 63%, P=.18). For patients w ithout SAMCs, there were also no differences in abstinence rates (integrate d care, 66% vs independent care, 73%; P=.23) and there was a slight but non significant trend of higher costs for the integrated care group ($367.96 vs $324.09, P=.19). However, patients with SAMCs (n=341) were more likely to be abstinent in the integrated care group than the independent care group ( 69% vs 55%, P=.006; odds ratio [OR], 1.90; 95% confidence interval [CI], 1. 22-2.97). This was true for both those with medical (OR, 3.38; 95% Cl, 1.68 -6.80) and psychiatric (OR, 2.10; 95% Cl, 1.04-4.25) SAMCS. Patients with S AMCs had a slight but nonsignificant trend of higher costs in the integrate d care group ($470.81 vs $427.95, P=.14). The incremental cost-effectivenes s ratio per additional abstinent patient with an SAMC in,the integrated car e group was $1581. Conclusions Individuals with SAMCs benefit from integrated medical and subs tance abuse treatment, and such an approach can be cost-effective. These fi ndings are relevant given the high prevalence and cost of medical condition s among substance abuse patients, new developments in medications for addic tion, and recent legislation on parity of substance abuse with other medica l benefits.