Decentralization of viral load testing to improve HIV care and treatment cascade in rural Tanzania: observational study from the Kilombero and Ulanga Antiretroviral Cohort

INTRODUCTION: Monitoring HIV viral load (HVL) in people living with HIV (PLHIV) on antiretroviral therapy (ART) is recommended by the World Health Organization. Implementation of HVL testing programs have been affected by logistic and organizational challenges. Here we describe the HVL monitoring cascade in a rural setting in Tanzania and compare turnaround times (TAT) between an on-site and a referral laboratory. METHODS: In a nested study of the prospective Kilombero and Ulanga Antiretroviral Cohort (KIULARCO) we included PLHIV aged >/= 15 years, on ART for >/= 6 months after implementation of routine HVL monitoring in 2017. We assessed proportions of PLHIV with a blood sample taken for HVL, whose results came back, and who were virally suppressed (HVL /= 1000 copies/mL). We described the proportion of PLHIV with unsuppressed HVL and adequate measures taken as per national guidelines and outcomes among those with low-level viremia (LLV; 100-999 copies/mL). We compare TAT between on-site and referral laboratories by Wilcoxon rank sum tests. RESULTS: From 2017 to 2020, among 4,454 PLHIV, 4,238 (95%) had a blood sample taken and 4,177 (99%) of those had a result. Of those, 3,683 (88%) were virally suppressed. In the 494 (12%) unsuppressed PLHIV, 425 (86%) had a follow-up HVL (102 (24%) within 4 months and 158 (37%) had virologic failure. Of these, 103 (65%) were already on second-line ART and 32/55 (58%) switched from first- to second-line ART after a median of 7.7 months (IQR 4.7-12.7). In the 371 (9%) PLHIV with LLV, 327 (88%) had a follow-up HVL. Of these, 267 (82%) resuppressed to < 100 copies/ml, 41 (13%) had persistent LLV and 19 (6%) had unsuppressed HVL. The median TAT for return of HVL results was 21 days (IQR 13-39) at the on-site versus 59 days (IQR 27-99) at the referral laboratory (p < 0.001) with PLHIV receiving the HVL results after a median of 91 days (IQR 36-94; similar for both laboratories). CONCLUSION: Robust HVL monitoring is achievable in remote resource-limited settings. More focus is needed on care models for PLHIV with high viral loads to timely address results from routine HVL monitoring

Prevalence, incidence and predictors of renal impairment in persons with HIV receiving protease-inhibitors in rural Tanzania

OBJECTIVE: Ritonavir-boosted protease inhibitors (bPI) in people living with HIV (PLWH) have been associated with renal impairment. Limited data are available from rural sub-Saharan Africa. METHODS: Using data from the Kilombero and Ulanga Antiretroviral Cohort Study (KIULARCO) in rural Tanzania from 2005-01/2020, we assessed the prevalence of renal impairment (estimated glomerular filtration rate <60 mL/min/1.73m2) at the time of switch from first-line antiretroviral treatment (ART) to bPI-regimen and the incidence of renal impairment on bPI. We assessed risk factors for renal impairment using logistic and Cox regression models. RESULTS: Renal impairment was present in 52/687 PLWH (7.6%) at the switch to bPI. Among 556 participants with normal kidney function at switch, 41 (7.4%) developed renal impairment after a median time of 3.5 (IQR 1.6-5.1) years (incidence 22/1,000 person-years (95%CI 16.1-29.8)). Factors associated with renal impairment at switch were older age (adjusted odds ratio (aOR) 1.55 per 10 years; 95%CI 1.15-2.11), body mass index (BMI) /=18kg/m2; 95%CI 1.28-6.14) and arterial hypertension (aOR 2.33; 95%CI 1.03-5.28). The risk of renal impairment was lower with increased duration of ART use (aOR 0.78 per one-year increase; 95%CI 0.67-0.91). The renal impairment incidence under bPI was associated with older age (adjusted hazard ratio 2.01 per 10 years; 95%CI 1.46-2.78). CONCLUSIONS: In PLWH in rural sub-Saharan Africa, prevalence and incidence of renal impairment among those who were switched from first-line to bPI-regimens were high. We found associations between renal impairment and older age, arterial hypertension, low BMI and time on ART