HIV viral suppression at different thresholds and duration of treatment in the dolutegravir treatment era in Sierra Leone: a nationwide survey

INTRODUCTION: Viral load assessment for people living with HIV is key for monitoring treatment and achieving the 95-95-95. In this study, we aimed to assess the degree of viral suppression at different thresholds and treatment duration after the introduction of dolutegravir-based therapy in ten public hospitals in Sierra Leone. METHODS: We used a cross-sectional study design to recruits patients aged 18 years or older between August 2022 and January 2023. Statistical analyses were performed using R-software. Logistic regression was used to assess factors independently associated with viral suppression. The level of significance was set at P < 0.05. RESULTS: Of the 2,253 patients recruited, 1,720 (76%) were women and 1,705 (76%) were receiving a fixed dose combination of tenofovir, lamivudine and dolutegravir. The median age and duration of anti-retroviral therapy (ART) was 36.0 (IQR, 28.0–45.0) years and 40.9 (IQR, 14.4–79.6) months, respectively. Using a threshold of HIV RNA < 1000 copies/mL, 1,715 (88.4%) patients on ART for more than 6 months were virally suppressed. Viral suppression rates were higher with dolutegravir-based (1,277, 89.5%) than efavirenz-based (418, 86.2%) ART. HIV RNA was < 200 copies/mL in 1,643 (84.6%) patients or < 50 copies/mL in 1,487 (76.6%) patients or between 50 and 999 copies/mL in 228 (11.7%) patients. Viral suppression rates at different ART durations (months) were as follows: 84.2% (≤ 3), 88.8% (4–6), 90.9% (6–12), and 88.1% (> 12). Viral suppression rates were higher for patients aged 40 or older (40–50 years: aOR 2.05, 95%CI 1.41–3.04, P < 0.01; 50–60 years: aOR 2.51, 95%CI 1.53–4.35, P < 0.01; >60 years: aOR 2.69, 95%CI 1.28–6.63, P = 0.02). Men had 49% lower odds of viral suppression than women (aOR 0.50, 95% CI 0.38–0.67, P < 0.01). CONCLUSION: We report a viral suppression rate of 88.4% among patients on treatment for at least 6 months, with higher rate of suppression with dolutegravir than efavirenz. Factors associated with virological suppression were age and gender, emphasizing the need for innovative differentiated ART delivery models to optimize viral suppression and achieve the 95% target.