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

The safety and immunogenicity of vaccines administered to pregnant women living with HIV: a systematic review and meta-analysis

Background

Human Immunodeficiency Virus (HIV)-exposed uninfected (HEU) infants have a higher burden of infectious diseases related morbidity and mortality compared with HIV-unexposed uninfected (HUU). Immunization of pregnant women living with HIV (PWLWH) could reduce the severity and burden of infectious diseases for HEU in early infancy.

Methods

We conducted a systematic review of safety and immunogenicity of vaccines administered to PWLWH and meta-analyses to test the overall effect of immunogenicity comparing pregnant women without HIV (PWWH) to PWLWH. We searched MEDLINE, Embase, Web of Science, Virtual Health Library and Cochrane databases in accordance with PRISMA guidelines for randomized controlled trials and observational studies. Review articles, case series, conference abstracts, and animal studies were excluded. Studies were included from inception to 6th September 2023, with no language restrictions. Random effects meta-analyses were performed for immunogenicity using Review manager (RevMan) analysis software version 5.4.1, Geometric Mean Titer (GMT) values were transformed to obtain the mean and standard deviation within RevMan, the effect size was computed and reported as mean difference with respective 95% confidence intervals. The review was registered with PROSPERO CRD42021289081.

Findings

We included 12 articles, comprising 3744 pregnant women, 1714 were PWLWH given either influenza, pneumococcal or an investigational Group B streptococcal (GBS) vaccine. Five studies described safety outcomes, and no increase in adverse events was reported in PWLWH compared to PWWH. The GMT increase from baseline to 28-35 weeks post vaccination in HA units ranged from 12.4 (95% CI: 9.84-14.9) to 238.8 (95% CI: 0.35-477.9). Meta-analyses of influenza vaccines showed the pooled geometric mean difference in Hemagglutination Inhibition (HAI) titers post vaccination was 56.01 (95% CI: 45.01-67.01), p < 0.001. The increase was less in PWLWH when compared with PWWH: -141.76 (95% CI: -194.96, -88.55), p < 0.001.

Interpretation

There are limited data on the safety and immunogenicity of vaccines given to PWLWH making policy consideration in this group difficult when new vaccines are introduced. With new vaccines on the horizon, PWLWH need to be included in studies to promote vaccine confidence for this special population.

Funding

This work was funded by Medical Research Council Joint Clinical Trials Round 9 [MR/T004983/1].

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.

Early Childhood Growth Parameters in South African Children with Exposure to Maternal HIV Infection and Placental Insufficiency

Maternal HIV exposure and intrauterine growth restriction (IUGR) due to placental insufficiency both carry major risks to early child growth. We compared the growth outcomes of children aged 18 months who had abnormal umbilical artery resistance indices (UmA-RI), as a marker of placental insufficiency, with a comparator group of children with normal UmA-RI during pregnancy, as mediated by maternal HIV infection. The cross-sectional study included 271 children, grouped into four subgroups based on HIV exposure and history of normal/abnormal UmA-RI, using available pregnancy and birth information. Standard procedures were followed to collect anthropometric data, and z-scores computed as per World Health Organization growth standards. Lower length-for-age z-scores (LAZ) were observed in children who were HIV-exposed-uninfected (CHEU) (-0.71 ± 1.23; p = 0.004) and who had abnormal UmA-RI findings (-0.68 ± 1.53; p < 0.001). CHEU with abnormal UmA-RI had lower LAZ (-1.3 ± 1.3; p < 0.001) and weight-for-age z-scores (WAZ) (-0.64 ± 0.92; p = 0.014) compared to the control group. The prevalence of stunting was 40.0% in CHEU with abnormal UmA-RI and 16.0% in CHEU with normal UmA-RI (p < 0.001; p = 0.016, respectively). In conclusion, maternal HIV exposure and placental insufficiency are independent risk factors for childhood stunting, with this risk potentiated when these two risk factors overlap.

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.