Maternal drug use in perinatal HIV studies. The Women and Infants Transmission Study

In-utero exposure to zidovudine-containing antiretroviral therapy and clonal hematopoiesis in HIV-exposed uninfected newborns

OBJECTIVE

Zidovudine (ZDV) has been extensively used in pregnant women to prevent vertical transmission of HIV but few studies have evaluated potential mutagenic effects of ZDV during fetal development.

DESIGN

Our study investigated clonal hematopoiesis in HIV-exposed uninfected (HEU) newborns, 94 of whom were ZDV-exposed and 91 antiretroviral therapy (ART)-unexposed and matched for potential confounding factors.

METHODS

Utilizing high depth sequencing and genotyping arrays, we comprehensively examined blood samples collected during the first week after birth for potential clonal hematopoiesis associated with fetal ZDV exposure, including clonal single nucleotide variants (SNVs), small insertions and deletions (indels), and large structural copy number or copy neutral alterations.

RESULTS

We observed no statistically significant difference in the number of SNVs and indels per person in ZDV-exposed children (adjusted ratio [95% confidence interval, CI] for expected number of mutations = 0.79 [0.50--1.22], P = 0.3), and no difference in the number of large structural alterations. Mutations in common clonal hematopoiesis driver genes were not found in the study population. Mutational signature analyses on SNVs detected no novel signatures unique to the ZDV-exposed children and the mutational profiles were similar between the two groups.

CONCLUSION

Our results suggest that clonal hematopoiesis at levels detectable in our study is not strongly influenced by in-utero ZDV exposure; however, additional follow-up studies are needed to further evaluate the safety and potential long-term impacts of in-utero ZDV exposure in HEU children as well as better investigate genomic aberrations occurring late in pregnancy.

Association between zidovudine-containing antiretroviral therapy exposure in utero and leukocyte telomere length at birth

OBJECTIVES

Zidovudine (ZDV) is a nucleoside reverse transcriptase inhibitor that could cause telomere shortening through inhibition of telomerase. We examined the association between in utero exposure to ZDV and telomere length at birth in HIV-exposed-uninfected (HEU) newborns.

METHODS

We selected 94 ZDV-exposed HEU children and 85 antiretroviral therapy (ART)-unexposed HEU children from the Surveillance Monitoring for ART Toxicities Study and the Women and Infants Transmission Study. We assessed relative telomere length in stored peripheral blood mononuclear cells taken in the first 7 days of life using quantitative polymerase chain reaction. We used linear regression to compare relative telomere length between ZDV-exposed and ART-unexposed children. We additionally evaluated relative telomere length according to maternal and infant characteristics.

RESULTS

Relative telomere length was longer in ZDV-exposed children compared with ART-unexposed individuals (adjusted mean ratio difference 0.21, 95% confidence interval 0.15-0.28, P < 0.001). We found an inverse correlation between maternal HIV RNA levels and infant relative telomere length (-0.06 per log10 copies, 95% confidence interval -0.08 to -0.03, P < 0.001). Relative telomere length was not associated with maternal CD4 cell count, maternal age, gestational age, sex, sample storage time, or maternal substance use (P > 0.05).

CONCLUSION

Relative telomere length was longer in ZDV-exposed infants. This difference may reflect beneficial health effects of ART during pregnancy, as we observed an inverse association with maternal HIV RNA levels.

Infant peripheral blood repetitive element hypomethylation associated with antiretroviral therapy in utero

The use of combination antiretroviral therapy (cART) to prevent HIV mother-to-child transmission during pregnancy and delivery is generally considered safe. However, vigilant assessment of potential risks of these agents remains warranted. Epigenetic changes including DNA methylation are considered potential mechanisms linking the in utero environment with long-term health outcomes. Few studies have examined the epigenetic effects of prenatal exposure to pharmaceutical agents, including antiretroviral therapies, on children. In this study, we examined the methylation status of the LINE-1 and ALU-Yb8 repetitive elements as markers of global DNA methylation alteration in peripheral blood mononuclear cells obtained from newborns participating in the Pediatric HIV/AIDS Cohort Study SMARTT cohort of HIV-exposed, cART-exposed uninfected infants compared to a historical cohort of HIV-exposed, antiretroviral-unexposed infants from the Women and Infants Transmission Study Cohort. In linear regression models controlling for potential confounders, we found the adjusted mean difference of AluYb8 methylation of the cART-exposed compared to the -unexposed was -0.568 (95% CI: -1.023, -0.149) and for LINE-1 methylation was -1.359 (95% CI: -1.860, -0.857). Among those exposed to cART, subjects treated with atazanavir (ATV), compared to those on other treatments, had less AluYb8 methylation (-0.524, 95% CI: -0.025, -1.024). Overall, these results suggest a small but statistically significant reduction in the methylation of these repetitive elements in an HIV-exposed, cART-exposed cohort compared to an HIV-exposed, cART-unexposed historic cohort. The potential long-term implications of these differences are worthy of further examination.

Dramatic decline in substance use by HIV-infected pregnant women in the United States from 1990 to 2012

OBJECTIVE

We aimed to describe temporal changes in substance use among HIV-infected pregnant women in the United States from 1990 to 2012.

DESIGN

Data came from two prospective cohort studies (Women and Infants Transmission Study and Surveillance Monitoring for Antiretroviral Therapy Toxicities Study).

METHODS

Women were classified as using a substance during pregnancy if they self-reported use or had a positive biological sample. To account for correlation between repeated pregnancies by the same woman, generalized estimating equation models were used to test for temporal trends and evaluate predictors of substance use.

RESULTS

Over the 23-year period, substance use among the 5451 HIV-infected pregnant women sharply declined; 82% of women reported substance use during pregnancy in 1990, compared with 23% in 2012. Use of each substance decreased significantly (P < 0.001 for each substance) in an approximately linear fashion, until reaching a plateau in 2006. Multivariable models showed substance use was inversely associated with receiving antiretroviral therapy. Among the subset of 824 women with multiple pregnancies under observation, women who used a substance in their previous pregnancy were at elevated risk of substance use during their next pregnancy (risk ratio, 5.71; 95% confidence interval, 4.63-7.05).

CONCLUSION

A substantial decrease in substance use during pregnancy was observed between 1990 and 2012 in two large US cohorts of HIV-infected women. Substance use prevalence in these cohorts became similar to that of pregnant women in the general US population by the mid-2000s, suggesting that the observed decrease may be due to an epidemiological transition of the HIV epidemic among women in the United States.

Mental health of HIV-seropositive women during pregnancy and postpartum period: a comprehensive literature review

With growing numbers of HIV-seropositive (HIV+) women of child-bearing age and increased access to effective clinical protocols for preventing mother-to-child transmission (MTCT) of HIV, mental health-related factors have become increasingly relevant due to their potential to affect the women's quality of life, obstetric outcomes and risk of MTCT. This review synthesizes evidence from 53 peer-reviewed publications examining mental health-related variables in pregnant and postpartum HIV+ women. The presentation of results is organized by the level of socioeconomic resources in the countries where studies were conducted (i.e., high-, middle-, and low-income countries). It is concluded that psychiatric symptoms, particularly depression, and mental health vulnerabilities (e.g., inadequate coping skills) are widespread among pregnant HIV+ women globally and have a potential to affect psychological well-being, quality of life and salient clinical outcomes. The current body of evidence provides rationale for developing and evaluating clinical and structural interventions aimed at improving mental health outcomes and their clinical correlates in pregnant HIV+ women.

Neurodevelopment and in utero antiretroviral exposure of HIV-exposed uninfected infants

OBJECTIVE

Antiretroviral (ARV) drugs are routinely provided to HIV-infected pregnant women to prevent HIV mother-to-child transmission. Although ARV use has significantly reduced mother-to-child transmission to <2% in the United States, it remains crucial to monitor uninfected infants and children for adverse consequences of in utero ARV exposure.

METHODS

We studied neurodevelopmental function in HIV-exposed uninfected children who were enrolled in Pediatric AIDS Clinical Trials Group 219/219C, a multisite, prospective, cohort study. Mental and motor functioning were assessed with the Bayley Scales of Infant Development (BSID), first and second editions. ARV exposure information was collected during pregnancy or within the first years of life. Linear regression methods were used to evaluate the association of in utero ARV exposure on Mental Developmental Index and Psychomotor Developmental Index at 2 years of age, controlling for demographic factors (age, gender, and race/ethnicity) and potential confounders: test version, primary language, primary caregiver, caregiver education level, low birth weight, geographic and urban/rural location, birth year, and maternal illicit drug use.

RESULTS

Among 1840 infants who were born between 1993 and 2006, 1694 (92%) were exposed to ARV in utero and 146 (8%) were not exposed. After controlling for confounders, children who were exposed in utero to any ARV did not have lower Mental Developmental Index and Psychomotor Developmental Index scores than unexposed children. Among low birth weight infants, significantly higher BSID scores were observed for prenatally ARV-exposed than unexposed children. Maternal illicit drug use was reported for 17% of mothers but was not associated with BSID scores.

CONCLUSIONS

Mental and motor functioning scores were not lower for infants with in utero ARV exposure compared with no exposure. Although these results are reassuring, continued evaluation of uninfected children with in utero ARV exposure for long-term adverse outcomes is important.

Early immunological predictors of neurodevelopmental outcomes in HIV-infected children

BACKGROUND

A previous analysis of children infected with human immunodeficiency virus (HIV) in the Women and Infants Transmission Study showed a strong correlation between low activated CD8(+) T lymphocytes in the first 2 months of life and good immunological prognosis. We sought to extend these observations to neurodevelopmental prognosis.

METHODS

Ninety-eight HIV-infected children born before 1994 with flow cytometric data from the first 2 months of life and adequate neurodevelopmental testing through age 30 months were studied. Children were divided into those with low (<or=5% CD8(+)HLA-DR(+) cells or <or=25% CD8(+)CD38(+) cells) or high (>5% CD8(+)HLA-DR(+) cells or >25% CD8(+)CD38(+) cells) immune activation at 1 and/or 2 months of age. Analysis was performed using survival analysis, Cox's proportional hazard regression, and longitudinal regression models.

RESULTS

Absence of immune activation, measured as <or=5% CD8(+)HLA-DR(+) cells, was strongly associated with better performance on the psychomotor developmental index of the Bayley scales of infant development through the third year of life. This association persisted after adjustment for CD4 cell count, viral load, and progression to acquired immunodeficiency syndrome (P= .005). An association with the mental development index was also present (P= .048). Significant association between neurodevelopmental outcomes and <or=25% CD8(+)CD38(+) cells was not seen.

CONCLUSIONS

In this prospective cohort study of HIV-infected children, there was a significant favorable association of low immune activation in peripheral T cells at age 1 or 2 months, measured by a low percentage of CD8(+)HLA-DR(+) cells, with subsequent psychomotor and mental development. This association was independent of other indices of severity and progression of HIV infection.

Effects of Polymorphisms of Chemokine Receptors on Neurodevelopment and the Onset of Encephalopathy in Children with Perinatal HIV-1 Infection

This study examined the effects of chemokine receptor polymorphisms on neurodevelopment and the onset of encephalopathy in children with perinatal HIV-1 infection. Infected children (N = 121) between the ages of I and 72 months were categorized into dichotomous groups (heterozygous or homozygous mutant vs. homozygous wild type) for each chemokine receptor 2 (CCR2) and chemokine receptor 5 (CCR5) allele. Neurodevelopmental measures included the Bayley Scales of Infant Development (BSID)for children age < or = 30 months and the McCarthy Scales of Children's Abilities (MSCA) for children aged > 30 months. A basic linear spline was used to model the mean value at each visit for the relevant test index, with determination of the slope between 4-12 months, 12-30 months, and 31-72 months of age. A mixed model analysis of variance was used to compare differences between slopes (AP) and intercepts (AX) according to the presence or absence of the specified CCR2 or CCR5 polymorphism. Survival analyses were used to compare the onset of encephalopathy by chemokine receptor allelic grouping. After adjusting for potential confounds, statistically significant differences emerged in CCR5-39353, 39356, and 39402. Although the protective effects appeared to be discrete and transient, children with mutant CCR5 genotypes exhibited better neurodevelopmental outcomes than children with the wild type alleles. Chemokine polymorphisms did not appear to impact the onset of encephalopathy. Although possibly a temporary effect, HIV-1 infected children with selected mutant chemokine receptor polymorphims CCR5-39353, 39356, and 39402 may exhibit better neurodevelopmental outcome than children with the wild type allele.

Differences in neuropsychological performance associated with ethnicity in children with HIV-1 infection: preliminary findings

This study investigated the relationship between ethnicity (African American and European American) and neuropsychological performance in two specific neuropsychological domains (language and speed of information processing) in a group of HIV-1+ children. The Expressive One-Word Picture Vocabulary Test-Revised and the Rapid Color Naming subtest of the Comprehensive Test of Phonological Processing were administered to 5- to 7-year-old children (n = 22) as part of a comprehensive research or clinical protocol. African American children scored lower than European American children (p < .05) on both procedures. The observed performance difference emerged despite the fact that there were no group differences in age, immunologic clinical categories, intellect, level of maternal education, or CD4+ percentage and after using stringent exclusionary criteria, including history of enrollment in special education services and the presence of other chronic medical conditions. The implications of such findings are discussed within biological and demographic frameworks.

The relationship of pregnancy to human immunodeficiency virus disease progression

OBJECTIVE

This study was undertaken to determine the effect of pregnancy on progression of human immunodeficiency virus (HIV) disease.

STUDY DESIGN

We compared the immunologic, clinical, and virologic courses of 953 women who had no additional pregnancy after their index pregnancy, with the courses of 329 women who had a second pregnancy subsequent to their index pregnancy. Baseline variables included use of antiretroviral therapy, and CD4 and HIV RNA values. A linear spline growth curve model was used to describe trajectories of variables. The Cox proportional hazards model was used to assess selected covariates on the time to development of clinical class C events or death.

RESULTS

Women with repeat pregnancies were less likely to be on antiretroviral therapy at baseline and had a higher CD4% count immediately after their first delivery. The average trajectory of CD4 values in the one-pregnancy group was almost identical to the average trajectory in the repeat pregnancy group. RNA levels in the single-pregnancy group started higher but ended lower than in the second-pregnancy group, although slope differences were modest. There were no significant differences in time to class C events, although women in the repeat-pregnancy group tended to survive longer.

CONCLUSION

Repeat pregnancies do not have significant effects on the course of HIV disease.

Timing of perinatal human immunodeficiency virus type 1 infection and rate of neurodevelopment. The Women and Infant Transmission Study Group

BACKGROUND

Identifying HIV-1-infected children who are at greatest risk for disease-related morbidities is critical for optimal therapeutic as well as preventive care. Several factors have been implicated in HIV-1 disease onset and severity, including maternal and infant host characteristics, viral phenotype and timing of HIV-1 infection. Early HIV-1 culture positivity, i.e. intrauterine infection, has been associated with poor immunologic, virologic and clinical outcomes in children of HIV-infected women. However, a direct effect of timing of infection on neurodevelopmental outcome in infancy has not yet been identified.

METHODS

Serial neurodevelopmental assessments were performed with 114 infants vertically infected with HIV-1 in a multicenter natural history, longitudinal study. Median mental and motor scores were compared at three time points. Longitudinal regression analyses were used to evaluate the neurodevelopmental functioning of children with early positive cultures and those with late positive cultures.

RESULTS

Early infected infants scored significantly lower than late infected infants by 24 months of age and beyond on both mental (P = 0.05) and motor (P = 0.03) measures. Early HIV-1 infection was associated with a decline in estimated motor scores of 1 standard score point per month compared with 0.28 point in the late infected group (P < 0.02). Estimated mental scores of the early infected group declined 0.72 point/ month, whereas the average decline of the late infected group was 0.30 point/month (P < 0.13).

CONCLUSION

Early HIV-1 infection increases a child's risk for poor neurodevelopmental functioning within the first 30 months of life.

Methadone treatment during pregnancy

Methadone maintenance has been used for decades to treat opioid-dependent pregnant women. The outcomes of pregnancies thus treated are vastly improved over the outcomes of pregnancies complicated by street drug use. Despite its long history of successful use during pregnancy, little is known about the long-term effects of methadone on the fetus and the newborn. Studies done in animals suggest there may be subtle effects on brain and behavior. Only recently have other treatments for opioid dependency during pregnancy been investigated. There is increasing evidence that altering the traditional methadone maintenance protocols may be beneficial, and that tapered withdrawal can be safely achieved under some circumstances.