Differences in Growth of HIV-exposed Uninfected Infants in Ethiopia According to Timing of In-utero Antiretroviral Therapy Exposure

Gut Microbiota and Other Factors Associated With Increased Regulatory T Cells in Hiv-exposed Uninfected Infants

HIV-exposed uninfected infants (HEU) have higher infectious morbidity than HIV-unexposed infants (HUU). HEU have multiple immune defects of unknown origin. We hypothesized that HEU have higher regulatory T cells (Treg) than HUU, which may dampen their immune defenses against pathogens. We compared 25 Treg subsets between HEU and HUU and sought the factors that may affect Treg frequencies. At birth, 3 Treg subsets, including CD4 + FOXP3 + and CD4 + FOXP3 + CD25+, had higher frequencies in 123 HEU than 117 HUU and 3 subsets were higher in HUU. At 28 and 62 weeks of life, 5 Treg subsets were higher in HEU, and none were higher in HUU. The frequencies of the discrepant Treg subsets correlated at birth with differential abundances of bacterial taxas in maternal gut microbiome and at subsequent visits in infant gut microbiomes. In vitro, bacterial taxa most abundant in HEU expanded Treg subsets with higher frequencies in HEU, recapitulating the in vivo observations. Other factors that correlated with increased Treg were low maternal CD4 + T cells in HEU at birth and male sex in HUU at 28 weeks. We conclude that maternal and infant gut dysbiosis are central to the Treg increase in HEU and may be targeted by mitigating interventions.

A Systematic Review on Cardiometabolic Risks and Perinatal Outcomes among Pregnant Women Living with HIV in the Era of Antiretroviral Therapy

Antiretroviral therapy (ART) regimens have been shown to cause metabolic changes in people living with HIV (PLWH), predisposing them to cardiometabolic disease (CVMD). However, such evidence is less established in pregnant women living with HIV (pWLWH) on ART. Pregnancy-induced cardiometabolic risks (CMR) can predispose to unfavourable pregnancy outcomes and further persist in the postpartum period, resolve, and recur in subsequent pregnancies, or emerge as newly diagnosed chronic diseases of ageing. Therefore, this systematic review aimed at synthesizing evidence on CMR and perinatal outcomes among pWLWH in the era of ART. We considered prospective and retrospective cohorts, case-control, cross-sectional, and interventional studies published in English. Specific keywords were used to conduct a thorough literature search on PubMed-Medline and Scopus following the Preferred Reporting Items for Systematic Review and Meta-Analysis guideline. Two investigators independently screened the search outputs and reviewed full texts of potentially eligible articles. Data extraction was conducted by one investigator and verified by the second investigator. Thirty-one relevant studies conducted on 20,904 pWLWH on ART across Africa, Asia, Europe, and America were included. Studies demonstrate inconclusive findings, especially on perinatal outcomes, but significant risks of gestational hypertension and dyslipidemia were reported in pWLWH on ART compared to the control group. Therefore, future studies should focus more on these perinatal outcomes, and their impact on postpartum maternal health and growth trajectories of uninfected infants born from pWLWH who are either on ART or ART-naïve in comparison to infants born of HIV-negative mothers over the life course, especially in HIV-burdened African countries.

Comparison of Feeding Practices and Growth of Urbanized African Infants Aged 6-12 Months Old by Maternal HIV Status in Gauteng Province, South Africa

Appropriate feeding practices are protective against malnutrition and poor growth. We compared feeding practices and growth in HIV-exposed-uninfected (HEU) and HIV-unexposed-uninfected (HUU) between 6-12 months of age in urbanized African infants in South Africa. A repeated cross-sectional analysis was used to determine differences in infant feeding practices and anthropometric measures by HIV exposure status at 6, 9, and 12 months in the Siyakhula study. The study included 181 infants (86 HEU; 95 HUU). Breastfeeding rates were lower in HEU vs. HUU infants at 9 (35.6% vs. 57.3%; p = 0.013) and 12 months (24.7% vs. 48.0%; p = 0.005). Introduction to early complementary foods was common (HEU = 16.2 ± 11.0 vs. HUU = 12.8 ± 9.3 weeks; p = 0.118). Lower weight-for-age Z-scores (WAZ) and head circumference-for-age Z-scores (HCZ) were found in HEU infants at birth. At 6 months, WAZ, length-for-age Z-scores (LAZ), HCZ, and mid-upper-arm circumference-for-age Z-scores (MUACAZ) were lower in HEU vs. HUU infants. At 9 months, lower WAZ, LAZ, and MUACAZ were found in HEU vs. HUU infants. At 12 months, lower WAZ, MUACAZ, and weight-for-length Z-scores (-0.2 ± 1.2 vs. 0.2 ± 1.2; p = 0.020) were observed. HEU infants had lower rates of breastfeeding and poorer growth compared to HUU infants. Maternal HIV exposure affects the feeding practices and growth of infants.

Impact of antenatal antiretroviral drug exposure on the growth of children who are HIV-exposed uninfected: the national South African Prevention of Mother to Child Evaluation cohort study

BACKGROUND

The relationship between in-utero antiretroviral (ARV) drug exposure and child growth needs further study as current data provide mixed messages. We compared postnatal growth in the first 18-months of life between children who are HIV-exposed uninfected (CHEU) with fetal exposure to ARV drugs (prophylaxis or triple-drug therapy (ART)) and CHEU not exposed to ARVs. We also examined other independent predictors of postnatal growth.

METHODS

We analysed data from a national prospective cohort study of 2526 CHEU enrolled at 6-weeks and followed up 3-monthly till 18-months postpartum, between October 2012 and September 2014. Infant anthropometry was measured, and weight-for-age (WAZ) and length-for-age (LAZ) Z-scores calculated. Generalized estimation equation models were used to compare Z-scores between groups.

RESULTS

Among 2526 CHEU, 617 (24.4%) were exposed to ART since -pregnancy (pre-conception ART), 782 (31.0%) to ART commencing post-conception, 879 (34.8%) to maternal ARV prophylaxis (Azidothymidine (AZT)), and 248 (9.8%) had no ARV exposure. In unadjusted analyses, preterm birth rates were higher among CHEU with no ARV exposure than in other groups. Adjusting for infant age, the mean WAZ profile was lower among CHEU exposed to pre-conception ART [-0.13 (95% confidence interval - 0.26; - 0.01)] than the referent AZT prophylaxis group; no differences in mean WAZ profiles were observed for the post-conception ART (- 0.05 (- 0.16; 0.07)), None (- 0.05 (- 0.26; 0.16)) and newly-infected (- 0.18 (- 0.48; 0.13)) groups. Mean LAZ profiles were similar across all groups. In multivariable analyses, mean WAZ and LAZ profiles  for the ARV exposure groups were completely aligned. Several non-ARV factors including child, maternal, and socio-demographic factors independently predicted mean WAZ. These include child male (0.45 (0.35; 0.56)) versus female, higher maternal education grade 7-12 (0.28 (0.14; 0.42) and 12 + (0.36 (0.06; 0.66)) versus ≤ grade7, employment (0.16 (0.04; 0.28) versus unemployment, and household food security (0.17 (0.03; 0.31). Similar predictors were observed for mean LAZ.

CONCLUSION

Findings provide evidence for initiating all pregnant women living with HIV on ART as fetal exposure had no demonstrable adverse effects on postnatal growth. Several non-HIV-related maternal, child and socio-demographic factors were independently associated with growth, highlighting the need for multi-sectoral interventions. Longer-term monitoring of CHEU children is recommended.

Risk factors for stunting in children who are HIV-exposed and uninfected after Option B+ implementation in Malawi

Evidence suggests children HIV-exposed and uninfected (CHEU) experience poor growth. We analysed child anthropometrics and explored factors associated with stunting among Malawian CHEU. Mothers with HIV and their infants HIV-exposed were enroled in a nationally representative prospective cohort within the National Evaluation of Malawi's Prevention of Mother-to-Child HIV Transmission Programme after Option B+ implementation (2014-2018). Anthropometry was measured at enrolment (age 1-6 months), visit 1 (approximately 12 months), and visit 2 (approximately 24 months). Weight-for-age (WAZ) and length-for-age (LAZ) z-scores were calculated using World Health Organization Growth Standards; underweight and stunting were defined as WAZ and LAZ more than 2 standard deviations below the reference median. Multivariable logistic regression restricted to CHEU aged 24 months (±3 months) was used to identify factors associated with stunting. Among 1211 CHEU, 562/1211 attended visit 2, of which 529 were aged 24 months (±3 months) and were included. At age 24 months, 40.4% of CHEU were stunted and/or underweight, respectively. In multi-variable analysis, adjusting for child age and sex, the odds of stunting were higher among CHEU with infectious disease diagnosis compared to those with no diagnosis (adjusted odds ratio = 3.35 [95% confidence interval: 1.82-6.17]), which was modified by co-trimoxazole prophylaxis (p = 0.028). Infant low birthweight was associated with an increased odds of stunting; optimal feeding and maternal employment were correlated with reduced odds. This is one of the first studies examining CHEU growth since Option B+. Interventions to improve linear growth among CHEU should address their multi-faceted health risks, alongside maternal ART prescription, and follow-up of mother-child pairs.

Growth patterns of infants with in- utero HIV and ARV exposure in Cape Town, South Africa and Lusaka, Zambia

Background

Infants born HIV-exposed yet remain uninfected (HEU) are at increased risk of poorer growth and health compared to infants born HIV-unexposed (HU). Whether maternal antiretroviral treatment (ART) in pregnancy ameliorates this risk of poorer growth is not well understood. Furthermore, whether risks are similar across high burden HIV settings has not been extensively explored.

Methods

We harmonized data from two prospective observational studies conducted in Cape Town, South Africa, and Lusaka, Zambia, to compare weight-for-age (WAZ), length-for-age (LAZ) and weight-for-length (WLZ) Z-scores between infants who were HEU and HU, converting infant anthropometric measures using World Health Organisation Growth Standards adjusted for age and sex. Linear mixed effects models were fit to identify risk factors for differences in anthropometrics at 6–10 weeks and 6 months by infant HIV exposures status and by timing of exposure to maternal ART, either from conception or later in gestation.

Results

Overall 773 mother-infant pairs were included across two countries: women living with HIV (WLHIV), 51% (n = 395) with 65% on ART at conception and 35% initiating treatment in pregnancy. In linear mixed effects models, WAZ and WLZ at 6–10 weeks were lower among infants who were HEU vs HU [β = − 0.29 (95% CI: − 0.46, − 0.12) and [β = − 0.42 (95% CI: − 0.68, − 0.16)] respectively after adjusting for maternal characteristics and infant feeding with a random intercept for country. At 6 months, LAZ was lower [β = − 0.28 CI: − 0.50, − 0.06)] among infants who were HEU, adjusting for the same variables, with no differences in WAZ and WLZ. Within cohort evaluations identified different results with higher LAZ among infants who were HEU from Zambia at 6–10 weeks, [β = + 0.34 CI: + 0.01, + 0.68)] and lower LAZ among infants who were HEU from South Africa [β = − 0.30 CI: − 0.59, − 0.01)] at 6 months, without other anthropometric differences at either site.

Conclusion

Infant growth trajectories differed by country, highlighting the importance of studying contextual influences on outcomes of infants who were HEU.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-12476-z.

No Difference in Growth Outcomes up to 24 Months of Age by Duration of Exposure to Maternal Antiretroviral Therapy Among Children Who Are HIV-Exposed and Uninfected in Malawi

BACKGROUND

With the implementation of lifelong antiretroviral therapy (ART) for HIV treatment and prevention, the proportion of children exposed to ART in utero from conception is increasing. We estimated the effect of timing of ART exposure on growth of children HIV-exposed and uninfected (CHEU) up to Up to 24 months of age in Malawi.

METHODS

Data were collected from a prospective cohort of infants HIV-exposed aged 1-6 months (enrollment) and their mothers with HIV enrolled in the National Evaluation of Malawi's Prevention of Mother-to-Child Transmission of HIV Programme (2014-2018). Anthropometry was measured at enrollment, visit 1 (approximately 12 months), and visit 2 (approximately 24 months). Weight-for-age (WAZ) and length-for-age (LAZ) were calculated using the WHO Growth Standards. Multivariable mixed-effects models with linear splines for age were used to examine differences in growth by timing of ART exposure (from conception, first/second trimester, or third trimester/postpartum). Models were adjusted for confounders selected a priori guided by a conceptual framework. Hypothesized interactions and potential mediators were explored, and interactions with splines were included in final models if P < 0.1.

RESULTS

A total of 1,206 singleton CHEU and their mothers were enrolled and 563 completed the follow-up through 24 months of age. Moreover, 48% of CHEU were exposed to ART from conception, 40% from first/second trimester, and 12% from third trimester/postpartum. At enrollment, 12% of infants had low birthweight (LBW), 98% had been breastfed in past 7 days, and 57% were enrolled in an HIV care clinic. CHEU growth trajectories demonstrated cohort-wide growth faltering after the age of 12 months. Of 788 and 780 CHEU contributing to WAZ and LAZ multivariable models, respectively, there was no evidence of differences in mean WAZ or LAZ among those exposed from conception or first/second trimester vs. third trimester/postpartum and no evidence of a difference in WAZ or LAZ rate of change by timing of ART exposure (all interactions P > 1.0).

CONCLUSION

Reassuringly, ART exposure from conception was not associated with decreased WAZ or LAZ in CHEU Up 24 months of age. Overall growth trajectories suggest CHEU experience growth faltering after 12 months of age and may need support through and beyond the first 2 years of life.

A comparison of weight gain between HIV exposed uninfected and HIV unexposed uninfected infants who received KMC at Chris Hani Baragwanath Academic Hospital

INTRODUCTION

Kangaroo Mother Care (KMC) has been associated with improved growth in low birthweight infants and reduction in hypothermia, hypoglycaemia, apnoeas, sepsis, hospital stay, and mortality. The growth of HIV-infected children is poorer than those who are HIV-uninfected. There is paucity of data on weight gain in the HIV-exposed uninfected (HEU) infants compared to HIV-unexposed uninfected (HUU) infants receiving KMC.

AIM

This study compared the weight gain of HEU and infants HUU from admission to the KMC ward until 12 months corrected age (CA) follow-up visit.

METHODS

Retrospective record review of the neonates admitted in KMC at Chris Hani Baragwanath Hospital over a 2-year period (2012-2013). The weight gain was assessed via weight velocity using the formula; weight/kg/day from admission to KMC to discharge, and g/ week at term, 3, 6 and 9- and 12-months (CA). The demographics were collected and analyzed using Statistica.

RESULTS

Seventy-seven (129/166) percent of the mothers were HIV negative. HIV negative mothers were younger (25.9 vs. 31.6 years; p = 0.000) and had fewer pregnancies (p = 0.02). There was no difference between the gestational age (30.3 ± 2.53 vs. 30.8 ± 2.88 weeks; p = 0.35) and birthweight (1,345 g ± 234 vs. 1,314 g ± 209; p = 0.47) between HEU and HUU. There were no differences in the weight gain (23.83 g ± 12.2 vs. 23.22 g ± 15.2; p = 0.83) in KMC. There was no differences in weight gain at the different follow-up time points between the two groups.

CONCLUSION

Both HEU and HUU groups of infants showed reasonable weight gain despite maternal HIV status.

Differential effects of antiretroviral drug toxicity in male versus female children who are HIV-exposed but uninfected

: In recent years, widespread use of antiretroviral therapy (ART) during pregnancy has been increasingly effective in reducing risk of vertical transmission of HIV, with over 80% of pregnant women living with HIV now accessing ART, and a 41% reduction in new infections in children between 2010 and 2018. Despite these strides, the developmental toxicity of widely administered antiretroviral drugs (ARVs) remains poorly described and existing literature often fails to account for fetal and infant sex as a variable. Recent reports have identified associations between in-utero exposure to commonly used antiretroviral regimens and alteration in neurodevelopment, growth, and metabolism amongst children who are HIV-exposed but uninfected, with findings of sex differences in the prevalence and severity of ARV toxicity. These differences are potentially explained by variable exposure to ARV drugs in utero or exacerbation of existing sex-linked risk factors. Fetal ARV exposure is mediated by placental and fetal drug transporters and metabolic enzymes, which may contribute to the manifestation of sex differences. Existing evidence of sex differences in ARV toxicity in fetal development is concerning, and demands further research to guide optimal treatment options for maternal health and prevention of vertical HIV transmission.