title: A risk score to identify HIV-infected women most likely to become lost to follow-up in the postpartum period.
abstract: Access to lifelong combination antiretroviral therapy (cART) is expanding among HIV-infected pregnant and breastfeeding women throughout sub-Saharan Africa (SSA). For this strategy to meaningfully improve maternal HIV outcomes, retention in HIV care is essential. We developed a risk score to identify women with high likelihood of loss to follow-up (LTFU) at 6 months postpartum from HIV care, using data from public health facilities in Lusaka, Zambia. LTFU was defined as not presenting for HIV care within 60 days of the last scheduled appointment. We used logistic regression to assess demographic, obstetric and HIV predictors of LTFU and to develop a simple risk score. Sensitivity and specificity were assessed at each risk score cut-point. Among 2029 pregnant women initiating cART between 2009 and 2011, 507 (25%) were LTFU by 6 months postpartum. Parity, education, employment status, WHO clinical stage, duration of cART during pregnancy and number of antenatal care visits were associated with LTFU (p-value < .10). A risk score cut-point of 11 (42nd percentile) had 85% sensitivity (95% CI 82%, 88%) and 22% specificity (95% CI 20%, 24%) to detect women LTFU and would exclude 20% of women from a retention intervention. A risk score cut-point of 18 (69th percentile) identified the 23% of women with the highest probability of LTFU and had sensitivity 32% (95% CI 28%, 36%) and specificity 80% (95% CI 78%, 82%). A risk score approach may be useful to triage a subset of women most likely to be LTFU for targeted retention interventions.
authors.affiliation: a Department of Epidemiology , University of North Carolina , Chapel Hill , NC , USA.
authors.forename: Angela M
authors.initials: AM
authors.lastname: Bengtson
authors.affiliation: b Department of Obstetrics and Gynecology , University of North Carolina , Chapel Hill , NC , USA.
authors.forename: Carla J
authors.initials: CJ
authors.lastname: Chibwesha
authors.affiliation: a Department of Epidemiology , University of North Carolina , Chapel Hill , NC , USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Westreich
authors.affiliation: c Centre for Infectious Disease Research , Zambia , Africa.
authors.forename: Mwangelwa
authors.initials: M
authors.lastname: Mubiana-Mbewe
authors.affiliation: b Department of Obstetrics and Gynecology , University of North Carolina , Chapel Hill , NC , USA.|c Centre for Infectious Disease Research , Zambia , Africa.
authors.forename: Benjamin H
authors.initials: BH
authors.lastname: Chi
authors.affiliation: a Department of Epidemiology , University of North Carolina , Chapel Hill , NC , USA.|d Department of Medicine , University of North Carolina , Chapel Hill , NC , USA.
authors.forename: William C
authors.initials: WC
authors.lastname: Miller
authors.affiliation: b Department of Obstetrics and Gynecology , University of North Carolina , Chapel Hill , NC , USA.
authors.forename: Muntanga
authors.initials: M
authors.lastname: Mapani
authors.affiliation: a Department of Epidemiology , University of North Carolina , Chapel Hill , NC , USA.
authors.forename: Brian W
authors.initials: BW
authors.lastname: Pence
authors.affiliation: e Department of Public Health , University of Zambia School of Medicine , Lusaka , Zambia , Africa.
authors.forename: Patrick
authors.initials: P
authors.lastname: Musonda
authors.affiliation: b Department of Obstetrics and Gynecology , University of North Carolina , Chapel Hill , NC , USA.
authors.forename: Jeffrey Sa
authors.initials: JS
authors.lastname: Stringer
authors.affiliation: a Department of Epidemiology , University of North Carolina , Chapel Hill , NC , USA.
authors.forename: Audrey
authors.initials: A
authors.lastname: Pettifor
mesh_terms: D000328:Adult; D023241:Antiretroviral Therapy, Highly Active; D001942:Breast Feeding; D003266:Continuity of Patient Care; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000517:prevention & control / Q000523:psychology; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D016015:Logistic Models; D059012:Lost to Follow-Up; D009035:Mothers / Q000706:statistics & numerical data; D010352:Patient Dropouts / Q000706:statistics & numerical data*; D049590:Postpartum Period; D011247:Pregnancy; D011295:Prenatal Care; D012189:Retrospective Studies; D012306:Risk; D018570:Risk Assessment; D015024:Zambia
keywords: HIV; antiretroviral; loss to follow-up; postpartum; pregnancy