Intervention to Prevent Major Depression in Primary Care: A Cluster Randomized Trial.

BACKGROUND

Not enough is known about universal prevention of depression in adults.

OBJECTIVE

To evaluate the effectiveness of an intervention to prevent major depression.

DESIGN

Multicenter, cluster randomized trial with sites randomly assigned to usual care or an intervention. (ClinicalTrials.gov: NCT01151982).

SETTING

10 primary care centers in each of 7 cities in Spain.

PARTICIPANTS

Two primary care physicians (PCPs) and 5236 nondepressed adult patients were randomly sampled from each center; 3326 patients consented and were eligible to participate.

INTERVENTION

For each patient, PCPs communicated individual risk for depression and personal predictors of risk and developed a psychosocial program tailored to prevent depression.

MEASUREMENTS

New cases of major depression, assessed every 6 months for 18 months.

RESULTS

At 18 months, 7.39% of patients in the intervention group (95% CI, 5.85% to 8.95%) developed major depression compared with 9.40% in the control (usual care) group (CI, 7.89% to 10.92%) (absolute difference, -2.01 percentage points [CI, -4.18 to 0.16 percentage points]; P = 0.070). Depression incidence was lower in the intervention centers in 5 cities and similar between intervention and control centers in 2 cities.

LIMITATION

Potential self-selection bias due to nonconsenting patients.

CONCLUSION

Compared with usual care, an intervention based on personal predictors of risk for depression implemented by PCPs provided a modest but nonsignificant reduction in the incidence of major depression. Additional study of this approach may be warranted.

PRIMARY FUNDING SOURCE

Institute of Health Carlos III.