Zimbabwe: low-cost, brief psychological intervention helps people with HIV stay virally suppressed

But the ‘Friendship Bench’ does not help people who were not already virally suppressed
Image credit: Rainer Kwiotek/Friendship Bench.

Results from a study published in PLOS Global Public Health show that people with HIV and common mental disorders in Zimbabwe can benefit from a low-cost and brief psychological intervention called the Friendship Bench to improve their mental health outcomes and, consequently, sustain viral suppression on antiretroviral therapy. However, the intervention had no effect on viral suppression in people who were not virally suppressed at the time they joined the study.  

When adhered to, antiretroviral therapy leads to viral suppression, which in turn halts HIV progression into AIDS, enables a near-normal life expectancy and prevents HIV transmission to sexual partners. However, common mental disorders, including depression and anxiety, have a negative impact on adherence to antiretroviral therapy, contributing to viral non-suppression and mortality.

The Friendship Bench is an approach to psychological therapy that has been developed and provided in Zimbabwe – a low-income country with the fifth highest HIV prevalence globally – for over ten years. It is a brief intervention for depression and other mental disorders delivered by lay counsellors in primary care. It employs a ‘task shifting’ approach – delegating tasks usually performed by more highly trained personnel to those with less training, such as nurses and lay counsellors. This allows services to be scaled up in resource-limited settings. Just in 2023, over 2,000 lay counsellors provided Friendship Bench therapy to over 300,000 people, with or without HIV, in Zimbabwe.


virological suppression

Halting of the function or replication of a virus. In HIV, optimal viral suppression is measured as the reduction of viral load (HIV RNA) to undetectable levels and is the goal of antiretroviral therapy.


A mental health problem causing long-lasting low mood that interferes with everyday life.


A feeling of unease, such as worry or fear, which can be mild or severe. Anxiety disorders are conditions in which anxiety dominates a person’s life or is experienced in particular situations.

control group

A group of participants in a trial who receive standard treatment, or no treatment at all, rather than the experimental treatment which is being tested. Also known as a control arm.


Studies aim to give information that will be applicable to a large group of people (e.g. adults with diagnosed HIV in the UK). Because it is impractical to conduct a study with such a large group, only a sub-group (a sample) takes part in a study. This isn’t a problem as long as the characteristics of the sample are similar to those of the wider group (e.g. in terms of age, gender, CD4 count and years since diagnosis).

Usually, Friendship Bench lay counsellors are older community volunteers, or “grandmothers”, who do not have prior medical knowledge but receive training. This covers problem-solving therapy (addressing life-stress issues and focusing on finding solutions to concrete problems) and simple behavioural activation (helping to develop problem-solving skills in order to tackle issues that affect the person’s mood). The intervention takes place on wooden benches that are located in discreet areas near health clinics, where each attendee receives up to six one-to-one counselling sessions.

It has been shown that the Friendship Bench can improve symptoms of common mental disorders and depression in adults with or without HIV attending primary care. However, whether or not it is effective in terms of viral suppression in people with HIV receiving antiretroviral therapy remained to be seen.

This brought Dr Victoria Simms from the London School of Hygiene & Tropical Medicine, and colleagues from the University of Zimbabwe, King’s College London and the University of Bern, Switzerland, to assess whether the Friendship Bench could improve viral suppression, but also common mental disorders in people living with HIV, by comparing it to usual care. The study was run in eight primary care clinics providing HIV care and other services in high or middle-density suburbs of Harare.

One limitation of the study is that it was not randomised: six of the clinics provided Friendship Bench counselling, while the other two served as a control arm. In these control clinics, Enhanced Usual Care was provided by nurses and included mental health assessment, information provision, prescription of antidepressants and referral to specialist services.

HIV-positive clinic attendees could participate in the study if they had been taking an antiretroviral regimen for at least three months, lived in the clinic catchment area and had a common mental disorder diagnosed. Diagnosis was based on the Shona-Symptom Questionnaire, a 14-item assessment tool for these conditions developed in Zimbabwe, which includes locally accepted idioms of distress. Patients with more serious mental health challenges such as suicidal ideation, psychotic symptoms or dementia could not join the study.

At the start and the end of the study (after six months), clinical, sociodemographic and mental health data were collected, using three other internationally validated questionnaires on health, anxiety and disability. The study primary outcome was the proportion of participants not showing viral suppression (with a viral load of 400 copies or above) after six months of follow-up. Secondary outcomes were mental health symptoms, as assessed with questionnaires.

In total, there were 700 patients in the study: 500 received Friendship Bench counselling and 200 received Enhanced Usual Care. Overall, 579 participants had viral load test results available at the start (baseline) and at the end of the study (81% in the bench arm vs 86% in the control arm), allowing for a primary outcome analysis of their data. Also, 568 participants had mental health data available at six months (around 81% in both arms).

In the sample of 579 participants, mean age was 41 years. Most participants were female: 348 (85%) in the Friendship Bench arm and 127 (74%) in the Enhanced Usual Care arm.

At the start of the study, 80 (14%) participants were not virally suppressed (14% and 13% in the bench and the control arms, respectively), which unfortunately is in line with other data from Zimbabwe. Both the duration on antiretroviral therapy and the severity of common mental diseases were similar in the two study arms. In the whole sample, prevalence of major depression and of anxiety was 56% and 47%, respectively, while that of severe depression and severe generalised anxiety disorder was also high: 12% and 23%, respectively.

Among 499 participants already virally suppressed at baseline, those who attended the Friendship Bench clinics were three times less likely to see their viral load increase above 400 copies, compared with those receiving usual care (3% vs 9%; p = 0.002). However, in people not virally suppressed at baseline, viral non-suppression rates did not differ between the two arms after six months (54% vs 55%). The other significant result from the study is that out of all 579 participants in the cohort, those attending the Friendship Bench clinics were six times less likely to screen for a common mental health disorder at the end of the study than those attending the Enhanced Usual Care clinics (aDID = – 21.6%; 95% CI – 36.5% to – 6.7%; p = 0.008).

Based on these results, the investigators emphasise the need to incorporate mental health support into primary care for people living with HIV in countries with high HIV burden. They also highlight the importance of improving viral suppression rates, for example through the use of problem-solving therapy to address barriers to antiretroviral adherence. Therefore, incorporating adherence to antiretroviral therapy in training for Friendship Bench counsellors should be looked at, as this has proven effective in some US and South African programmes. Simms and colleagues also say that “qualitative research should be conducted, to deepen the understanding of adherence behaviour in those living with HIV who have common mental disorders, and to explore the needs of counsellors in supporting people with adherence difficulties.”

Last year, another study of the effect of the Friendship Bench on antiretroviral therapy adherence, viral suppression and mental health symptoms reached similar conclusions. Led by Dr Andreas Haas from the University of Bern and the Friendship Bench Project, it recruited 516 participants with characteristics and outcomes pretty similar to participants’ in the research by Simms and colleagues, except that the trial was run in a rural district of Zimbabwe. Another major difference was that it was a randomised trial: 16 health facilities provided either Friendship Bench counselling or only standard care to 516 patients, who knew to which comparison arm they were assigned (open-label).

The trial found an effect of the Friendship Bench on common mental disorder symptoms, but not on adherence or viral suppression. Haas and colleagues highlight that this latter result may be due to several factors, including the use in a rural area of assessment tools that are potentially “too urban”, and the absence of skill-based adherence training for Friendship Bench counsellors. “The further development of the Friendship Bench intervention to incorporate adherence training may be a promising approach to reach those at high risk of poor HIV outcomes,” they say.


Simms V et al. Effect of a brief psychological intervention for common mental disorders on HIV viral suppression: A non-randomised controlled study of the Friendship Bench in Zimbabwe. PLOS Global Public Health 4: e0001492, 2024.


Haas AD et al. Effect of the Friendship Bench Intervention on Antiretroviral Therapy Outcomes and Mental Health Symptoms in Rural Zimbabwe - A Cluster Randomized Trial. JAMA Network Open. 6: e2323205, 2023.