OBJECTIVES

To determine the effectiveness of collaborative care in reducing depression in primary care patients with diabetes or heart disease using practice nurses as case managers.

DESIGN

A two-arm open randomised cluster trial with wait-list control for 6 months. The intervention was followed over 12 months.

SETTING

Eleven Australian general practices, five randomly allocated to the intervention and six to the control.

PARTICIPANTS

400 primary care patients (206 intervention, 194 control) with depression and type 2 diabetes, coronary heart disease or both.

INTERVENTION

The practice nurse acted as a case manager identifying depression, reviewing pathology results, lifestyle risk factors and patient goals and priorities. Usual care continued in the controls.

MAIN OUTCOME MEASURE

A five-point reduction in depression scores for patients with moderate-to-severe depression. Secondary outcome was improvements in physiological measures.

RESULTS

Mean depression scores after 6 months of intervention for patients with moderate-to-severe depression decreased by 5.7±1.3 compared with 4.3±1.2 in control, a significant (p=0.012) difference. (The plus-minus is the 95% confidence range.) Intervention practices demonstrated adherence to treatment guidelines and intensification of treatment for depression, where exercise increased by 19%, referrals to exercise programmes by 16%, referrals to mental health workers (MHWs) by 7% and visits to MHWs by 17%. Control-practice exercise did not change, whereas referrals to exercise programmes dropped by 5% and visits to MHWs by 3%. Only referrals to MHW increased by 12%. Intervention improvements were sustained over 12 months, with a significant (p=0.015) decrease in 10-year cardiovascular disease risk from 27.4±3.4% to 24.8±3.8%. A review of patients indicated that the study's safety protocols were followed.

CONCLUSIONS

TrueBlue participants showed significantly improved depression and treatment intensification, sustained over 12 months of intervention and reduced 10-year cardiovascular disease risk. Collaborative care using practice nurses appears to be an effective primary care intervention.

TRIAL REGISTRATION

ACTRN12609000333213 (Australia and New Zealand Clinical Trials Registry).