BACKGROUND: HIV RNA viral load (VL) remains the most reliable marker to assess HIV treatment success to date. The Zambia HIV guideline define viral load suppression as any VL test result of below 1000 copies/ml and all HIV clients on Antiretroviral Treatment for at least 6 months with VL above 1000 copies/ml should be enrolled on enhanced adherence counselling (EAC). Studies suggest that low-level viremia (LLV) was associated with increased risk of treatment failure. We hypothesized that clients who develop unsuppressed VL above 1000 copies/ml could have had a progressive increase in their VLs from previous tests. Identifying HIV clients with LLV in Lusaka could help take proactive steps in preventing treatment failure.
METHODS: We extracted data from electronic medical records of clients on ART for at least 6 months with at least one VL result documented between April 2018 and January 2022 in Lusaka. We conducted retrospective cohort analysis to determine what proportion of clients with latest VL above 1000 copies had recorded LLV - defined as VL copies/ml between 60 and 999 - on their previous VL lab tests. Logic regression model was used to measure association between LLV and demographic characteristics of clients.
RESULTS: 8610 records showed a VL >1000 copies on the last VL test; 4836 (56.1%) were female. 2707 (31.4%) had at least one previous VL on file of which 1498 (55.3%) were male, 1761(65%) aged between 20 and 44 years and 2169 (80%) on ART for more than 24 months. 732(27.0%) of patients with VL > 1000 copies had a LLV in the past. The odds of having a VL above 1000 amongst those with past LLV was 3.4 times higher than those with no LLV [aOR 3.41(3.12,3.72),p<0.00]. Males patients had an odd of 1.3 (aOR 1.34 – 1.4;p<0.00) compared to females.
CONCLUSIONS: Our analysis revealed that LLV is associated with risk of future raised viral load above 1000 copies. Males with LLV are at higher risk of failing treatment. It would be justifiable to provide enhanced adherence counseling to all clients with VL between 60 and 999 copies to prevent occurrence of viral mutation and treatment failure.