HIV Exposure and Formula Feeding Predict Under-2 Mortality in HIV-Uninfected Children, Botswana

OBJECTIVES

To prospectively assess rates and detailed predictors of morbidity and mortality among HIV-exposed uninfected children and HIV-unexposed children in Botswana in a more recent era.

STUDY DESIGN

We enrolled HIV-infected and HIV-uninfected mothers and their children in the prospective observational Tshipidi study at 2 sites (1 city and 1 village) in Botswana from May 2010-July 2012. Live-born children and their mothers were followed for 24 months postpartum. Detailed sociodemographic data, health, and psychosocial characteristics were collected at baseline and prospectively, and health outcomes ascertained. Mothers chose infant feeding method with counselling.

RESULTS

A total of 893 live-born HIV-uninfected children (436 HIV-exposed uninfected, 457 HIV-unexposed) were followed. HIV-infected mothers had a median CD4 count of 410 cells/mm3, 32% took 3-drug antiretroviral treatment during pregnancy, 67% took only zidovudine, and 1% took <2 weeks of any antiretrovirals antepartum. Twenty four-month vital status was available for 888 (99.4%) children. HIV-exposed uninfected children had a significantly higher risk of death compared with children of HIV-uninfected mothers (5.0% vs 1.8%) (adjusted hazard ratio 3.27, 95% CI 1.44-7.40). High collinearity between maternal HIV status and child feeding method precluded analysis of these factors as independent predictors of mortality. Preterm birth, low birth weight, and congenital anomaly were also associated with mortality (in separate analyses), but maternal socioeconomic factors, depression, substance use, and social support were not significant predictors.

CONCLUSIONS

The strongest predictors of 24-month mortality among children in Botswana were HIV exposure and formula feeding, although the relative contribution of these factors to child health could not be separated.

Effect of Gestational Age at Tenofovir-Emtricitabine-Efavirenz Initiation on Adverse Birth Outcomes in Botswana

Among human immunodeficiency virus-positive women in Botswana on the recommended first-line antiretroviral therapy regimen, tenofovir-emtricitabine-efavirenz, initiated within the first or early second trimester, we found no increased risk of stillbirth, neonatal death, preterm/very preterm delivery, or the infant being born small or very small for gestational age. Treatment with tenofovir-emtricitabine-efavirenz <1 year before conception increased the risk of preterm delivery slightly over late-second-trimester treatment initiation (adjusted risk ratio, 1.33 [95% confidence interval, 1.04-1.70]).

Comparative safety of dolutegravir-based or efavirenz-based antiretroviral treatment started during pregnancy in Botswana: an observational study

Background

Global rollout of dolutegravir-based antiretroviral therapy (ART) has been hampered in part by insufficient safety data in pregnancy. We compared birth outcomes among women initiating dolutegravir-based ART with those among women initiating efavirenz-based ART in pregnancy in Botswana.

Methods

In this observational study, we captured birth outcome data at eight government hospitals throughout Botswana (~45% of all deliveries in the country) in an ongoing study that started on Aug 15, 2014. In 2016, Botswana changed first-line ART from efavirenz-tenofovir-emtricitabine to dolutegravir-tenofovir-emtricitabine, including for pregnant women. This analysis includes women starting either efavirenz-based ART or dolutegravir-based ART during singleton pregnancy (regimen started and delivery occurring between Aug 15, 2014, and Aug 15, 2016, for efavirenz-based ART and between Nov 1, 2016, and Sept 30, 2017, for dolutegravir-based ART). We excluded births to mothers who had switched regimen or stopped ART. The primary outcomes were the combined endpoints of any adverse outcome (stillbirth, preterm birth [<37 weeks’ gestation], small for gestational age [SGA; less than the tenth percentile of birthweight by gestational age], or neonatal death [within 28 days of age]) and severe adverse outcomes (stillbirth, neonatal death, very preterm birth [<32 weeks’ gestation], and very SGA [less than the third percentile of birthweight by gestational age]). We fitted log-binomial regression models, controlling for maternal age, gravidity, and education, to estimate adjusted risk ratios (aRRs).

Findings

Our analysis included 1729 pregnant women who initiated dolutegravir-based ART and 4593 who initiated efavirenz-based ART. The risk for any adverse birth outcome among women on dolutegravir versus efavirenz was similar (33·2% vs 35·0%; aRR 0·95, 95% CI 0·88–1·03), as was the risk of any severe birth outcome (10·7% vs 11·3%; 0·94, 0·81–1·11). We found no significant differences by regimen in the individual outcomes of stillbirth, neonatal death, preterm birth, very preterm birth, SGA, or very SGA.

Interpretation

Adverse birth outcomes were similar among pregnant women who initiated dolutegravir-based and efavirenz-based ART. Dolutegravir-based ART can be safely initiated in pregnancy.

Funding

National Institutes of Health.

Similar HIV protection from four weeks of zidovudine versus nevirapine prophylaxis among formula-fed infants in Botswana

Background

The World Health Organization HIV guidelines recommend either infant zidovudine (ZDV) or nevirapine (NVP) prophylaxis for the prevention of intrapartum mother-to-child HIV transmission (MTCT) among formula-fed infants. No study has evaluated the comparative efficacy of infant prophylaxis with twice daily ZDV versus once daily NVP in exclusively formula-fed HIV-exposed infants.

Methods

Using data from the Mpepu Study, a Botswana-based clinical trial investigating whether prophylactic co-trimoxazole could improve infant survival, retrospective analyses of MTCT events and Division of AIDS (DAIDS) Grade 3 or Grade 4 occurrences of anaemia or neutropenia were performed among infants born full-term (≥ 37 weeks gestation), with a birth weight ≥ 2500 g and who were formula-fed from birth. ZDV infant prophylaxis was used from Mpepu Study inception. A protocol modification mid-way through the study led to the subsequent use of NVP infant prophylaxis.

Results

Among infants qualifying for this secondary retrospective analysis, a total of 695 (52%) infants received ZDV, while 646 (48%) received NVP from birth for at least 25 days but no more than 35 days. Confirmed intrapartum HIV infection occurred in two (0.29%) ZDV recipients and three (0.46%) NVP recipients (p = 0.68). Anaemia occurred in 19 (2.7%) ZDV versus 12 (1.9%) NVP (p = 0.36) recipients. Neutropenia occurred in 28 (4.0%) ZDV versus 21 (3.3%) NVP recipients (p = 0.47).

Conclusions

Both ZDV and NVP resulted in low intrapartum transmission rates and no significant differences in severe infant haematologic toxicity (DAIDS Grade 3 or Grade 4) among formula-fed full-term infants with a birthweight ≥ 2500 g.

Comparative Safety of Antiretroviral Treatment Regimens in Pregnancy

IMPORTANCE

Maternal antiretroviral treatment (ART) started before conception may increase the risk for adverse birth outcomes among women with human immunodeficiency virus (HIV) infection, but whether the risk differs by ART regimen is unknown.

OBJECTIVE

To compare the risk for selected birth outcomes by maternal ART regimen.

DESIGN, SETTING, AND PARTICIPANTS

This observational birth outcomes surveillance study compared all live births and stillbirths with a gestational age of at least 24 weeks in 8 geographically dispersed government hospitals throughout Botswana (approximately 45% of births nationwide). Data were collected from August 15, 2014, through August 15, 2016.

EXPOSURES

Births among HIV-infected women who started 3-drug ART regimens before their last menstrual period and did not switch or stop ART in pregnancy were considered to be ART exposed from conception.

MAIN OUTCOMES AND MEASURES

The primary outcomes were any adverse birth outcome, including stillbirth, preterm birth (<37 weeks), small size for gestational age (SGA; <10th percentile of weight for gestational age) or neonatal death (<28 days from delivery), and any severe adverse outcome, including very preterm birth (<32 weeks), very SGA (<3rd percentile of weight for gestational age), stillbirth, and neonatal death.

RESULTS

Information was available for 47 027 of 47 124 births (99.8%) at surveillance maternity hospitals (mean [SD] age of mothers, 26.86 [6.45] years). Among 11 932 HIV-exposed infants, 5780 (48.4%) were ART exposed from conception. Adverse birth outcomes were more common among HIV-exposed infants than HIV-unexposed infants (39.6% vs 28.9%; adjusted relative risk [ARR], 1.40; 95% CI, 1.36-1.44). The risk for any adverse birth outcome was lower among infants exposed from conception to tenofovir disoproxil fumarate, emtricitabine, and efavirenz (TDF-FTC-EFV) (901 of 2472 [36.4%]) compared with TDF-FTC and nevirapine (NVP) (317 of 760 [41.7%]; ARR, 1.15; 95% CI, 1.04-1.27); TDF-FTC and lopinavir-ritonavir (TDF-FTC-LPV-R) (112 of 231 [48.5%]; ARR, 1.31; 95% CI, 1.13-1.52); zidovudine, lamivudine, and NPV (ZDV-3TC-NVP) (647 of 1365 [47.4%]; ARR, 1.30; 95% CI, 1.20-1.41); or ZDV-3TC-LPV-R (75 of 167 [44.9%]; ARR, 1.21; 95% CI, 1.01-1.45). The risk for any severe adverse outcome was also lower among infants exposed from conception to TDF-FTC-EFV (303 of 2472 [12.3%]) compared with TDF-FTC-NVP (136 of 760 [17.9%]; ARR, 1.44; 95% CI, 1.19-1.74), TDF-FTC-LPV-R (45 of 231 [19.5%]; ARR, 1.58; 95% CI, 1.19-2.11), ZDV-3TC-NVP (283 of 1365 [20.7%]; ARR, 1.68; 95% CI, 1.44-1.96), or ZDV-3TC-LPV-R (39 of 167 [23.4%]; ARR, 1.93; 95% CI, 1.43-2.60) from conception. Compared with TDF-FTC-EFV, all other regimens were associated with higher risk for SGA; ZDV-3TC-NVP was associated with higher risk of stillbirth, very preterm birth, and neonatal death; and ZDV-3TC-LPV-R was associated with higher risk for preterm birth, very preterm birth, and neonatal death.

CONCLUSIONS AND RELEVANCE

Among infants exposed to ART from conception, TDF-FTC-EFV was associated with a lower risk for adverse birth outcomes than other ART regimens.

HIV-exposed children account for more than half of 24-month mortality in Botswana

Background

The contribution of HIV-exposure to childhood mortality in a setting with widespread antiretroviral treatment (ART) availability has not been determined.

Methods

From January 2012 to March 2013, mothers were enrolled within 48 h of delivery at 5 government postpartum wards in Botswana. Participants were followed by phone 1–3 monthly for 24 months. Risk factors for 24-month survival were assessed by Cox proportional hazards modeling.

Results

Three thousand mothers (1499 HIV-infected) and their 3033 children (1515 HIV-exposed) were enrolled. During pregnancy 58 % received three-drug ART, 23 % received zidovudine alone, 11 % received no antiretrovirals (8 % unknown); 2.1 % of children were HIV-infected by 24 months. Vital status at 24 months was known for 3018 (99.5 %) children; 106 (3.5 %) died including 12 (38 %) HIV-infected, 70 (4.7 %) HIV-exposed uninfected, and 24 (1.6 %) HIV-unexposed. Risk factors for mortality were child HIV-infection (aHR 22.6, 95 % CI 10.7, 47.5 %), child HIV-exposure (aHR 2.7, 95 % CI 1.7, 4.5) and maternal death (aHR 8.9, 95 % CI 2.1, 37.1). Replacement feeding predicted mortality when modeled separately from HIV-exposure (aHR 2.3, 95 % CI 1.5, 3.6), but colinearity with HIV-exposure status precluded investigation of its independent effect. Applied at the population level (26 % maternal HIV prevalence), an estimated 52 % of child mortality occurs among HIV-exposed or HIV-infected children.

Conclusions

In a programmatic setting with high maternal HIV prevalence and widespread maternal and child ART availability, HIV-exposed and HIV-infected children still account for most deaths at 24 months. Lack of breastfeeding was a likely contributor to excess mortality among HIV-exposed children.

Follow-up of infants diagnosed with HIV - Early Infant Diagnosis Program, Francistown, Botswana, 2005-2012

The 2011 prevalence of human immunodeficiency virus (HIV) among pregnant women in Botswana was 30.4%. High coverage rates of HIV testing and antiretroviral prophylaxis have reduced the rate of mother-to-child transmission of HIV in Botswana from as high as 40% with no prophylaxis to <4% in 2011. In June 2005, the national Early Infant Diagnosis (EID) Program began testing HIV-exposed infants (i.e., those born to HIV-infected mothers) for HIV using polymerase chain reaction (PCR) at 6 weeks postpartum. During 2005-2012, follow-up of all HIV-infected infants diagnosed in all 13 postnatal care facilities in Francistown, Botswana, was conducted to ascertain patient outcomes. A total of 202 infants were diagnosed with HIV. As of September 2013, 82 (41%) children were alive and on antiretroviral therapy (ART), 79 (39%) had died, and 41 (20%) were either lost to follow-up, had transferred, or their mothers declined ART. Despite success in preventing mother-to-child transmission in Botswana, results of the EID program highlight the need for early diagnosis of HIV-infected infants, prompt initiation of ART, and retention in care.