An Empiric Risk Scoring Tool for Identifying High-Risk Heterosexual HIV-1–Serodiscordant Couples for Targeted HIV-1 Prevention

View/ Open
Date
2013Author
Kahle, Erin M.
Hughes, James P.
Lingappa, Jairam R.
John-Stewart, Grace
Celum, Connie
Nakku-Joloba, Edith
Njuguna, Stella
Mugo, Nelly
Bukusi, Elizabeth
Manongi, Rachel
Baeten, Jared M.
Metadata
Show full item recordAbstract
Background and objectives: Heterosexual HIV-1–serodiscordant
couples are increasingly recognized as an important source of
new HIV-1 infections in sub-Saharan Africa. A simple risk assessment
tool could be useful for identifying couples at highest risk for
HIV-1 transmission.
Methods: Using data from 3 prospective studies of HIV-1–serodiscordant
couples from 7 African countries and standard methods for
development of clinical prediction rules, the authors derived and validated
a risk scoring tool developed from multivariate modeling and
composed of key predictors for HIV-1 risk that could be measured in
standard research and clinical settings.
Results: The final risk score included age of the HIV-1–uninfected
partner, married and/or cohabiting partnership, number of children,
unprotected sex, uncircumcised male HIV-1–uninfected partner, and
plasma HIV-1 RNA in the HIV-1–infected partner. The maximum
risk score was 12, scores $5 were associated with an annual HIV-1
incidence of .3%, and couples with a score $6 accounted for only
28% of the population but 67% of HIV-1 transmissions. The area
under the curve for predictive ability of the score was 0.74 (95%
confidence interval: 0.70 to 0.78). Internal and external validation
showed similar predictive ability of the risk score, even when plasma
viral load was excluded from the risk score.
Conclusions: A discrete combination of clinical and behavioral
characteristics defines highest risk HIV-1–serodiscordant couples.
Discriminating highest risk couples for HIV-1 prevention programs
and clinical trials using a validated risk score could improve research
efficiency and maximize the impact of prevention strategies for
reducing HIV-1 transmission.