Costs of an intervention for primary care patients with medically unexplained symptoms: a randomized controlled trial.

Objective: This study sought to determine whether an intervention for patients with medically unexplained symptoms in primary care reduced total costs, components of cost, and longer-term costs and whether it led to decreased service use outside the health maintenance organization (HMO).
Methods: A randomized controlled trial involving 206 patients with medically unexplained symptoms was conducted in a staff-model HMO. The protocol emphasized the provider-patient relationship and included cognitive-behavioral therapy and pharmacological management. Cost data for medical treatments were derived from the HMO's electronic database. Patients were interviewed about work days lost and out-of-pocket expenses for medical care outside the HMO.
Results: The difference in total costs ($1,071) for the 12-month intervention was not significant. The treatment group had significantly higher costs for antidepressants than the usual-care group ($192 higher) during the intervention, and a larger proportion received antidepressants. The intervention group used less medical care outside the HMO and missed one less work day per month on average (1.23 days), indicating a slight improvement in productivity, but the difference was not significant. The between-group difference in estimated total cost was smaller in the year after the intervention (difference of $341) but were not significant.
Conclusions: The total costs for the intervention group were not significantly different, but the group had greater use of antidepressants. Coupled with findings of improved mental health outcomes for this group in a previous study, the results indicate that the intervention may be cost-effective. The longer-term impact needs to be further studied.