Peebles, K., Palanee-Phillips, T., Balkus, J. E., Beesham, I., Makkan, H., Deese, J., Smit, J., Heffron, R., Morrison, C. S., Philip, N. M., Malahleha, M., Kasaro, M., Naidoo, Y., Nielson, T., Reddy, K., Kotze, P., Ahmed, K., Rees, H., Baeten, J. M., Barnabas, R. V., … Evidence for Contraceptive Options and HIV Outcomes (ECHO) Trial Consortium (2020).
Journal of acquired immune deficiency syndromes (1999), 10.1097/QAI.0000000000002436. Advance online publication. https://doi.org/10.1097/QAI.0000000000002436
Background: HIV-1 risk scoring tools could help target provision of prevention modalities such as pre-exposure prophylaxis (PrEP). Recent research suggests that risk scores for women aged 18-45 may not predict risk well among young women aged 18-24. We evaluated the predictive performance of age-specific risk scores compared to the existing non-age-specific VOICE risk score, developed for women aged 18-45.
Methods: We conducted a secondary analysis of the Evidence for Contraceptive Options and HIV Outcomes Trial to develop and internally validate HIV-1 risk scores for women aged 18-24 and 25-35 in South Africa. Candidate predictors included baseline demographic, clinical, behavioral, and contextual characteristics readily available in clinical settings. The VOICE risk score was applied to women aged 18-35. We evaluated predictive performance of each risk score by area under the receiver operating characteristic curve (AUC).
Results: Predictive performance of all risk scores was moderate, with AUC (95% CI) of 0.64 (0.60, 0.67) among women aged 18-24, 0.68 (0.62, 0.73) among those aged 25-35, and 0.61 (0.58 0.65) for the VOICE risk score applied to women aged 18-35; AUC was similar in internal validation. Among women aged 18-24, HIV-1 incidence was high even at low risk scores, at 3.9 per 100 person-years (95% CI: 3.2, 4.7).
Conclusion: All risk scores were moderately predictive of HIV-1 acquisition, and age-specific risk scores performed only marginally better than the VOICE non-age-specific risk score. Approaches for targeted PrEP provision to women in South Africa may require more extensive data than are currently available to improve prediction.