The epidemiology of adolescents living with perinatally acquired HIV: A cross-region global cohort analysis.

BACKGROUND: Globally, the population of adolescents living with perinatally acquired HIV (APHs) continues to expand. In this study, we pooled data from observational pediatric HIV cohorts and cohort networks, allowing comparisons of adolescents with perinatally acquired HIV in "real-life" settings across multiple regions. We describe the geographic and temporal characteristics and mortality outcomes of APHs across multiple regions, including South America and the Caribbean, North America, Europe, sub-Saharan Africa, and South and Southeast Asia. METHODS AND FINDINGS: Through the Collaborative Initiative for Paediatric HIV Education and Research (CIPHER), individual retrospective longitudinal data from 12 cohort networks were pooled. All children infected with HIV who entered care before age 10 years, were not known to have horizontally acquired HIV, and were followed up beyond age 10 years were included in this analysis conducted from May 2016 to January 2017. Our primary analysis describes patient and treatment characteristics of APHs at key time points, including first HIV-associated clinic visit, antiretroviral therapy (ART) start, age 10 years, and last visit, and compares these characteristics by geographic region, country income group (CIG), and birth period. Our secondary analysis describes mortality, transfer out, and lost to follow-up (LTFU) as outcomes at age 15 years, using competing risk analysis. Among the 38,187 APHs included, 51% were female, 79% were from sub-Saharan Africa and 65% lived in low-income countries. APHs from 51 countries were included (Europe: 14 countries and 3,054 APHs; North America: 1 country and 1,032 APHs; South America and the Caribbean: 4 countries and 903 APHs; South and Southeast Asia: 7 countries and 2,902 APHs; sub-Saharan Africa, 25 countries and 30,296 APHs). Observation started as early as 1982 in Europe and 1996 in sub-Saharan Africa, and continued until at least 2014 in all regions. The median (interquartile range [IQR]) duration of adolescent follow-up was 3.1 (1.5-5.2) years for the total cohort and 6.4 (3.6-8.0) years in Europe, 3.7 (2.0-5.4) years in North America, 2.5 (1.2-4.4) years in South and Southeast Asia, 5.0 (2.7-7.5) years in South America and the Caribbean, and 2.1 (0.9-3.8) years in sub-Saharan Africa. Median (IQR) age at first visit differed substantially by region, ranging from 0.7 (0.3-2.1) years in North America to 7.1 (5.3-8.6) years in sub-Saharan Africa. The median age at ART start varied from 0.9 (0.4-2.6) years in North America to 7.9 (6.0-9.3) years in sub-Saharan Africa. The cumulative incidence estimates (95% confidence interval [CI]) at age 15 years for mortality, transfers out, and LTFU for all APHs were 2.6% (2.4%-2.8%), 15.6% (15.1%-16.0%), and 11.3% (10.9%-11.8%), respectively. Mortality was lowest in Europe (0.8% [0.5%-1.1%]) and highest in South America and the Caribbean (4.4% [3.1%-6.1%]). However, LTFU was lowest in South America and the Caribbean (4.8% [3.4%-6.7%]) and highest in sub-Saharan Africa (13.2% [12.6%-13.7%]). Study limitations include the high LTFU rate in sub-Saharan Africa, which could have affected the comparison of mortality across regions; inclusion of data only for APHs receiving ART from some countries; and unavailability of data from high-burden countries such as Nigeria. CONCLUSION: To our knowledge, our study represents the largest multiregional epidemiological analysis of APHs. Despite probable under-ascertained mortality, mortality in APHs remains substantially higher in sub-Saharan Africa, South and Southeast Asia, and South America and the Caribbean than in Europe. Collaborations such as CIPHER enable us to monitor current global temporal trends in outcomes over time to inform appropriate policy responses.

Risk factors and prognostic significance of platelet count abnormalities in children with HIV infection on antiretroviral therapy.

OBJECTIVES: To establish the incidence, risk factors and correlation with survival of thrombocytopenia and thrombocytosis (T/T) among children with HIV infection (CWH). DESIGN: A retrospective nested case control study of patients 0-18 years in five Baylor International Pediatric AIDS Initiative (BIPAI) centers in sub-Sahara Africa, 2004-2014. METHODS: Clinical and laboratory variables including complete blood counts (CBC) were extracted from the BIPAI electronic medical record system. Incident cases of T/T were identified and frequency-matched on follow-up time with controls with normal platelets. We calculated the prevalence and incidence density of T/T and used conditional logistic regression to evaluate their association with selected clinical variables. We constructed Kaplan-Meier curves and a Cox proportional hazards model to evaluate the impact of T/T on survival. RESULTS: Two thousand, one hundred and nine children were sampled. The incidence density of thrombocytopenia was 1 per 57.9 (95% confidence interval [CI] 50.3-66.8) CWH-years. Thrombocytopenia was higher in children with WHO Stage III/IV, lower in children on zidovudine, and had no association with use of lamivudine or nevirapine, CD4 + suppression, age, and nutrition status. Thrombocytopenia was independently associated with 2.2-fold higher mortality (95% CI 1.62-3.08). The incidence density of thrombocytosis was 1 per 11.4 (95% CI 10.7-12.1) CWH-years. Thrombocytosis was associated with higher CD4 + cell count, younger age, and use of lamivudine or nevirapine, and did not impact survival. CONCLUSIONS: Platelet count is a clinically valuable biomarker of HIV clinical progression and mortality. Laboratory studies are necessary to elucidate the mechanisms of T/T.

Risk factors and prognostic significance of anemia in children with HIV infection on antiretroviral therapy.

OBJECTIVES: To establish the incidence, risk factors and prognostic effect of anemia in children living with HIV (CLWH). DESIGN: Retrospective nested case-control study of patients 0-18 years in five centers in sub-Saharan Africa, 2004-2014. METHODS: Incident cases of anemia were identified from electronic records and matched with CLWH without anemia. We calculated the incidence density of anemia and used conditional logistic regression to evaluate its association with risk factors, stratified by severity and type of anemia. We used a Cox proportional hazards model to evaluate the impact of anemia on survival. RESULTS: Two thousand, one hundred and thirty-seven children were sampled. The incidence density of anemia was 1 per 6.6 CLWH-years. Anemia was moderate in 31.8% and severe in 17.3% of anemia cases, which had 10-year mortality hazards of 3.4 and 4.5, respectively. Microcytic anemia (36% cases) was associated with 2.3-fold hazard of 10-year mortality, and with malnutrition and CD4 + suppression. Normocytic anemia (50.5% cases) was associated with 2.6-fold hazards of 10-year mortality, and with more severe malnutrition, CD4 + suppression, and WHO stage, but inversely associated with lamivudine and nevirapine therapy. Macrocytic anemia (13.5% cases) was neither associated with higher 10-year mortality nor with severe malnutrition or CD4 + suppression but was associated with WHO stage II/III and negatively associated with lamivudine therapy. CONCLUSION: This large multicountry study of CLWH found a high incidence density of anemia. Higher severity, normocytic and microcytic types of anemia were independently associated with long-term mortality. Laboratory studies are needed to decipher the mechanisms of anemia and how it impacts mortality in CLWH.