Effectiveness of a task-sharing collaborative care model for identification and management of depressive symptoms in patients with hypertension attending public sector primary care clinics in South Africa: pragmatic parallel cluster randomised controlled trial.

BACKGROUND

We tested the real-world effectiveness of a collaborative task-sharing model on depressive symptom reduction in hypertensive Primary Health Care (PHC) patients in South Africa.

METHOD

A pragmatic parallel cluster randomised trial in 20 clinics in the Dr Kenneth Kaunda district, North West province. PHC clinics were stratified by sub-district and randomised in a 1:1 ratio. Control clinics received care as usual (CAU), involving referral to PHC doctors and/or mental health specialists. Intervention clinics received CAU plus enhanced mental health training and a lay counselling referral service. Participant inclusion criteria were ≥ 18 years old, Patient Health Questionnaire-9 (PHQ-9) score ≥ 9 and receiving hypertension medication. Primary superiority outcome was ≥ 50% reduction in PHQ-9 score at 6 months. Statistical analyses comprised mixed effects regression models and a non-inferiority analysis.

TRIAL REGISTRATION NUMBER

NCT02425124.

RESULTS

Between April 2015 and October 2015, 1043 participants were enrolled (504 intervention and 539 control); 82% were women; half were ≥ 55 years. At 6 and 12 months follow-up, 91% and 89% of participants were interviewed respectively. One control group participant committed suicide. There was no significant difference in the primary outcome between intervention (N=256/456) and control (N=232/492) groups (55.9% versus 50.9%; adjusted risk difference = -0.04 ([95% CI = -0.19; 0.11], p = 0.6). The difference in PHQ-9 scores was within the defined equivalence limits at 6 and 12 months for the non-inferiority analysis.

LIMITATIONS

The trial was limited by low exposure to depression treatment by trial participants and by observed co-intervention in control clinics CONCLUSIONS: Incorporating lay counselling services within collaborative care models does not produce superior nor inferior outcomes to models with specialist only counselling services.

FUNDING

This work was supported by the UK Department for International Development [201446] as well as the National Institute of Mental Health, United States of America, grant number 1R01MH100470-01. Graham Thornicroft is supported by the National Institute for Health Research (NIHR) Applied Research Collaboration (ARC) South London at King's College London and King's College Hospital NHS Foundation Trust.