Higher Hospitalization Rates in Children Born HIV-exposed Uninfected in British Columbia, Canada, Between 1990 and 2012.

BACKGROUND: Compared with children who are HIV-unexposed and uninfected (CHUU), children who are HIV-exposed and uninfected (CHEU) experience more clinical complications. We investigated hospitalizations among CHEU by antenatal antiretroviral therapy (ART) exposure, in British Columbia, Canada. METHODS: This retrospective controlled cohort study used administrative health data from 1990 to 2012. CHEU and CHUU were matched 1:3 for age, sex and maternal geographical area of residence. We determined adjusted odds ratios (aORs) via conditional logistic regression, adjusting for maternal risk factors. RESULTS: A total of 446 CHEU and 1333 CHUU were included. Compared with CHUU, more CHEU experienced one or more lifetime hospitalization (47.3% vs. 29.8%), one or more neonatal hospitalization (40.4% vs. 27.6%), and any intensive care unit admission (28.5% vs. 9.2%). In adjusted analyses, CHEU experienced higher odds of any lifetime hospitalization (aOR 2.30, 95% confidence interval 1.81-2.91) and neonatal hospitalization (aOR 2.14, 95% confidence interval 1.68-2.73), compared with CHUU. There was, however, no difference in infection-related hospitalizations (9.0% vs. 7.5%), which were primarily respiratory tract infections among both CHEU and CHUU. CHEU whose mothers-initiated ART preconception showed lower odds of infection-related hospitalizations than children whose mothers initiated ART during pregnancy or received no ART. CONCLUSIONS: CHEU experienced increased odds of hospitalization relative to CHUU. A substantial number of CHEU hospitalizations occurred within the neonatal period and were ICU admissions. Initiating ART preconception may reduce the risk of infection-related hospitalizations. These findings reinforce the benefit of ART in pregnancy and the need for ongoing pediatric care to reduce hospitalizations.

Preterm Birth and Antiretroviral Exposure in Infants HIV-exposed Uninfected.

BACKGROUND: Infants HIV-exposed and uninfected (IHEU) who are born to women living with HIV are at an increased risk of preterm birth (PTB). Antenatal exposure to certain maternal antiretroviral therapy (ART) regimens has been associated with PTB, although existing studies in this domain are limited and report discordant findings. We determined odds of PTB among IHEU by antenatal ART regimens and timing of exposure, adjusting for maternal risk factors. METHODS: We retrospectively studied IHEU born in British Columbia (BC), Canada between 1990 and 2012 utilizing provincial health administrative databases. We included data from a control group of infants HIV-unexposed and uninfected (IHUU) matched ~3:1 for each IHEU on age, sex and geocode. RESULTS: A total of 411 IHEU and 1224 IHUU were included in univariable analysis. PTB was more frequent among IHEU (20%) compared with IHUU (7%). IHEU were more often antenatally exposed to alcohol, tobacco, as well as prescription, nonprescription, and illicit drugs (IHEU: 36%, 8% and 35%; vs. IHUU: 3%, 1% and 9%, respectively). After adjusting for maternal substance use and smoking exposure, IHEU remained at increased odds of PTB [adjusted odds ratio (aOR) (95% CI): 2.66; (1.73, 4.08)] compared with matched IHUU controls. ART-exposed IHEU (excluding those with NRTIs only ART) had lower adjusted odds of PTB compared with IHEU with no maternal ART exposure, regardless of regimen [aOR range: 0.16-0.29 (0.02-0.95)]. Odds of PTB between IHEU exposed to ART from conception compared with IHEU exposed to ART postconception did not differ [aOR: 0.91 (0.47, 1.76)]; however, both groups experienced lower odds of PTB compared with IHEU with no maternal ART [preconception: aOR: 0.28 (0.08, 0.89); postconception: aOR 0.30 (0.11, 0.83)]. CONCLUSIONS: BC IHEU were over twice as likely to be born preterm compared with demographically matched controls. Maternal substance use in pregnancy modulated this risk; however, we found no adverse associations of PTB with exposure to antenatal ART.

Elevated Blood Mitochondrial DNA in Early Life Among Uninfected Children Exposed to Human Immunodeficiency Virus and Combination Antiretroviral Therapy in utero.

BACKGROUND: Combination antiretroviral therapy (cART) during pregnancy prevents vertical transmission, but many antiretrovirals cross the placenta and several can affect mitochondria. Exposure to maternal human immunodeficiency virus (HIV) and/or cART could have long-term effects on children who are HIV exposed and uninfected (CHEU). Our objective was to compare blood mitochondrial DNA (mtDNA) content in CHEU and children who are HIV unexposed and uninfected (CHUU), at birth and in early life. METHODS: Whole-blood mtDNA content at birth and in early life (age 0-3 years) was compared cross-sectionally between CHEU and CHUU. Longitudinal changes in mtDNA content among CHEU was also evaluated. RESULTS: At birth, CHEU status and younger gestational age were associated with higher mtDNA content. These remained independently associated with mtDNA content in multivariable analyses, whether considering all infants, or only those born at term. Longitudinally, CHEU mtDNA levels remained unchanged during the first 6 months of life, and gradually declined thereafter. A separate age- and sex-matched cross-sectional analysis (in 214 CHEU and 214 CHUU) illustrates that the difference in mtDNA between the groups remains detectable throughout the first 3 years of life. CONCLUSION: The persistently elevated blood mtDNA content observed among CHEU represents a long-term effect, possibly resulting from in utero stresses related to maternal HIV and/or cART. The clinical impact of altered mtDNA levels is unclear.

Innate Immune Responses and Gut Microbiomes Distinguish HIV-Exposed from HIV-Unexposed Children in a Population-Specific Manner.

In both high- and low-income countries, HIV-negative children born to HIV-positive mothers (HIV exposed, uninfected [HEU]) are more susceptible to severe infection than HIV-unexposed, uninfected (HUU) children, with altered innate immunity hypothesized to be a cause. Both the gut microbiome and systemic innate immunity differ across biogeographically distinct settings, and the two are known to influence each other. And although the gut microbiome is influenced by HIV infection and may contribute to altered immunity, the biogeography of immune-microbiome correlations among HEU children have not been investigated. To address this, we compared the innate response and the stool microbiome of 2-y-old HEU and HUU children from Belgium, Canada, and South Africa to test the hypothesis that region-specific immune alterations directly correlate to differences in their stool microbiomes. We did not detect a universal immune or microbiome signature underlying differences between HEU versus HUU that was applicable to all children. But as hypothesized, population-specific differences in stool microbiomes were readily detected and included reduced abundances of short-chain fatty acid-producing bacteria in Canadian HEU children. Furthermore, we did not identify innate immune-microbiome associations that distinguished HEU from HUU children in any population. These findings suggest that maternal HIV infection is independently associated with differences in both innate immunity and the stool microbiome in a biogeographical population-specific way.

Transition from Pediatric to Adult HIV Care for Young Women Living with HIV.

Transitioning from pediatric to adult care is a complicated process for youth with chronic illnesses. This study elucidates the unique factors affecting transition preparedness and perception of adult HIV care among a cohort of young women with HIV. Between 2013 and 2015, 48 women with HIV, who had experience with pediatric HIV care, were enrolled in a large Canadian cohort study. Variables were self-reported during peer-administered surveys. Only 60% reported feeling prepared for transition. Having never had contact with child protection services (P = .049), never been in foster care (P = .011), never been in a group home (P = .036), reporting a higher current CD4 count (P = .033), and reporting a younger ideal age for transition (P = .041) were associated with transition preparedness. Eighty-four percent reported equivalent or better HIV care following transition. Correlates of equivalent/better care following transition included lower personal income (P = .023), higher CD4 count (P = .021), care by an adult infectious diseases specialist (P = .002), and transition preparedness (P = .005). Our findings highlight the importance of adequate transition preparation and its effect on perception of care following transition.

Investigation of factors associated with spontaneous preterm birth in pregnant women living with HIV.

OBJECTIVE: To investigate factors contributing to preterm birth (PTB), including cART use and clinical and social determinants of health, in women living with HIV (WLWH) from British Columbia, Canada. DESIGN: Retrospective observational cohort. METHODS: We investigated the effect of cART use and other clinical and demographic factors on spontaneous PTB (sPTB) rates (<37 weeks gestational age) among 631 singleton pregnancies between 1997 and 2018. Exposure to cART was modelled in comparison to no exposure, exposure in the first trimester, and between regimens. Differences in sPTB risk were estimated using time-dependent Cox's proportional hazards models. RESULTS: Overall, the sPTB rate was 16%. Cumulative cART use was associated with lower risk of PTB (Wald test P = 0.02; hazard ratio = 0.98, 95% CI = 0.96-0.99) and specific cART regimens were not associated with increased risk of sPTB. Exposure in the first trimester was not associated with sPTB and for each week of cART exposure, the risk of sPTB decreased by 2%. In a multivariable model, HIV viral load and substance use remained associated with risk of sPTB, but not cART exposure. CONCLUSION: The sPTB rate among pregnant WLWH was more than three times higher than in the general population. However, sPTB was not related specifically to use of cART; in fact, cART appeared to reduce the risk of sPTB. Uncontrolled HIV replication and substance use were associated with increased risk of sPTB among pregnant WLWH. This emphasizes the important role of prenatal care, access to cART, and smoking cessation and harm reduction to reduce the risk of sPTB in WLWH.

Challenges to achieving and maintaining viral suppression among children living with HIV.

OBJECTIVES: The objective of this study was to determine the time to, and durability of, viral suppression, among Canadian children living with HIV after initiation of combination antiretroviral therapy (cART). DESIGN: Prospective, multicenter Canadian cohort study (Early Pediatric Initiation Canada Child Cure Cohort), using both prospective and retrospectively collected data. METHODS: Kaplan-Meir survival estimates with Cox regression were used to determine the time to and risk factors for viral suppression, defined as two consecutive undetectable viral loads (<50 copies/ml) at least 30 days apart after initiation of cART. RESULTS: A total of 228 children were enrolled between December 2014 and December 2018. The time to viral suppression was significantly shorter among children initiating cART after 5 ≤ 5 vs. years or less of age [adjusted hazard ratio (aHR) 1.57, 95% confidence interval (CI) 1.13-2.20], among those born after 2010 vs. prior (aHR 1.71, 95% CI 1.04-2.79), and among those without child protection services involvement (aHR 1.44, 95% CI 1.03-2.01). Overall, 27% of children had a viral rebound within 3 years of achieving viral suppression; the risk of viral rebound was significantly lower among children initiating cART after 5 vs. 5 years or less of age [adjusted odds ratio (aOR): 0.32, 95% CI 0.13-0.81], those whose families had not received social assistance (aOR 0.16, 95% CI 0.06-0.46), and females vs. males (aOR 0.51, 95% CI 0.26-0.99). CONCLUSION: Only 73% of the children in the Early Pediatric Initiation Canada Child Cure Cohort had maintained viral suppression 3 years after it was first achieved. Age at cART initiation, and socioeconomic factors were predictors of both time to viral suppression and risk of viral rebound in this cohort.

Exploring the live birth rates of women living with HIV in British Columbia, Canada.

OBJECTIVE: To evaluate the birth rates of women living with HIV (WLWH) compared to the general population in British Columbia (BC), Canada. METHODS: We retrospectively reviewed clinical and population level surveillance data from 1997 to 2015. Live birth rates from 1997 to 2015 among WLWH aged 15-49 years were compared with those of all BC women. Next, the number of live births among WLWH with a live birth between 1997-2012 and HIV-negative controls matched 1:3 by geocode were compared. RESULTS: WLWH had a lower birth rate compared to all BC women [31.4 (95%CI, 28.6-34.3) vs. 40.0 (39.3-40.1)/1000 person years]. Stratified by age, WLWH aged 15-24 years had a higher birth rate while WLWH aged 25-49 years had a lower birth rate than BC women (p<0.01). Between 1997 and 2015, birth rates for both populations decreased among women aged 15-24 years, and increased among women aged 25-49 years, most strikingly among WLWH 35-49 years (p<0.01). When comparing WLWH with a live birth to HIV-negative geocode matched controls, WLWH aged 15-24 years (p = 0.03) and aged 25-34 years (p<0.01) had more live births than controls while WLWH aged 35-49 years did not (p = 0.06). CONCLUSIONS: On a population level, WLWH have lower birth rates than the general population. However, this is not observed among WLWH who have ever given birth compared with matched controls, suggesting that sociodemographic factors may play an important role. WLWH are increasingly giving birth in their later reproductive years. Taken together, our data supports the integration of reproductive health and HIV care.

Neurodevelopmental outcomes and in-utero antiretroviral exposure in HIV-exposed uninfected children.

OBJECTIVES: To assess and compare neurodevelopmental disorders in HIV-exposed uninfected (HEU) and HIV-unexposed uninfected (HUU) children in British Columbia, Canada. To determine associations between these outcomes and in-utero exposure to antiretroviral drugs. DESIGN: Retrospective controlled cohort study. METHODS: Data were collected on 446 HEU children and 1323 HUU children (matched ∼1 : 3 for age, sex, and geocode) born between 1990 and 2012. Multivariable logistic regressions determined odds ratios of neurodevelopmental disorder diagnoses. RESULTS: HEUs had three times higher odds of being born preterm (P < 0.0001), and a more than two-fold increase in odds for autism, disturbance of emotions, hyperkinetic syndrome, and developmental delay compared with matched HUUs (P < 0.02) in unadjusted analysis. This association was reduced [adjusted neurodevelopmental disorder odds ratio (AOR) = 1.67; 95% confidence interval: 1.12-2.48; P = 0.011] after adjusting for maternal substance use and/or smoking (children born after April 2000). Regardless of antiretroviral exposure type (i.e. none, treatment with one or multiple drug classes), HEUs had higher odds of any neurodevelopmental disorders compared with matched HUUs; however, there was no evidence suggesting any specific classes of antiretroviral drugs or exposure durations increased their likelihood of neurodevelopmental disorders. CONCLUSION: The results suggest no adverse associations between antiretroviral drugs and neurodevelopmental disorders within antiretroviral-exposed HEU children in our cohort. Prevalence of neurodevelopmental disorders is higher in HEUs; however, maternal substance use plays a role, as could other environmental factors not captured. These findings highlight a need for holistic support for pregnant women as well as careful developmental monitoring of HEUs past infancy, and access to early interventions, particularly among those born preterm and those exposed to addictive substances.

Health Care Provider Utilization and Cost of an mHealth Intervention in Vulnerable People Living With HIV in Vancouver, Canada: Prospective Study.

BACKGROUND: Improving adherence to combined antiretroviral therapy (cART) can be challenging, especially among vulnerable populations living with HIV. Even where cART is available free of charge, social determinants of health act as barriers to optimal adherence rates. Patient-centered approaches exploiting mobile phone communications (mHealth) have been shown to improve adherence to cART and promote achievement of suppressed HIV plasma viral loads. However, data are scarce on the health care provider (HCP) time commitments and health care costs associated with such interventions. This knowledge is needed to inform policy and programmatic implementation. OBJECTIVE: The purpose of this study was to approximate the resources required and to provide an estimate of the costs associated with running an mHealth intervention program to improve medication adherence in people living with HIV (PLWH). METHODS: This prospective study of HCP utilization and costs was embedded within a repeated measures effectiveness study of the WelTel short-message service (SMS) mHealth program. The study included 85 vulnerable, nonadherent PLWH in Vancouver, Canada, and resulted in improved medication adherence and HIV plasma viral load among participants. Study participants were provided mobile phones with unlimited texting (where required) and received weekly bidirectional text messages to inquire on their status for one year. A clinic nurse triaged and managed participants' responses, immediately logging all patient interactions by topic, HCP involvement, and time dedicated to addressing issues raised by participants. Interaction costs were determined in Canadian dollars based on HCP type, median salary within our health authority, and their time utilized as part of the intervention. RESULTS: Participant-identified problems within text responses included health-related, social, and logistical issues. Taken together, management of problems required a median of 43 minutes (interquartile range, IQR 17-99) of HCP time per participant per year, for a median yearly cost of Can $36.72 (IQR 15.50-81.60) per participant who responded with at least one problem. The clinic nurse who monitored the texts solved or managed 65% of these issues, and the remaining were referred to a variety of other HCPs. The total intervention costs, including mobile phones, plans, and staffing were a median Can $347.74/highly vulnerable participant per year for all participants or Can $383.18/highly vulnerable participant per year for those who responded with at least one problem. CONCLUSIONS: Bidirectional mHealth programs improve HIV care and treatment outcomes for PLWH. Knowledge about the HCP cost associated, here less than Can $50/year, provides stakeholders and decision makers with information relevant to determining the feasibility and sustainability of mHealth programs in a real-world setting. TRIAL REGISTRATION: ClinicalTrials.gov NCT02603536; https://clinicaltrials.gov/ct2/show/NCT02603536 (Archived by WebCite at http://www.webcitation.org/70IYqKUjV).

Missed opportunities for prevention of vertical HIV transmission in Canada, 1997-2016: a surveillance study.

BACKGROUND: Vertical HIV transmission has declined in Canada, but missed opportunities for prevention continue to occur. We sought to determine the adequacy, and changes over time in adequacy, of uptake of maternal and neonatal antiretroviral therapy for the prevention of vertical HIV transmission, and to determine the vertical transmission rate over time and according to adequacy of antenatal antiretroviral therapy during the combination antiretroviral therapy era in Canada. METHODS: The Canadian Perinatal HIV Surveillance Program collects data annually through retrospective chart review concerning HIV-infected women and their infants. We determined receipt of adequate antiretroviral treatment (antenatal combination antiretroviral treatment for ≥ 4 wk, intrapartum intravenous zidovudine treatment and 4-6 wk of infant oral zidovudine treatment) and predictors of inadequate antenatal combination antiretroviral therapy (none or < 4 wk) in Canada in 1997-2016. RESULTS: We identified 3785 mother-infant pairs. Uptake of 4 weeks or more of antenatal combination antiretroviral therapy increased over time across all provinces/territories and regardless of maternal race/ethnicity or risk category (p < 0.001). During 2011-2016, 92 women (6.5%) received no or less than 4 weeks of antenatal combination antiretroviral therapy, 146 women (10.7%) received no intrapartum zidovudine treatment, and 43 infants (3.1%) received less than 4 weeks of zidovudine treatment. In multivariate analysis restricted to 2011-2016, higher uptake of adequate antenatal combination antiretroviral therapy was seen among black women than among Indigenous (odds ratio [OR] 2.99, 95% confidence interval [CI] 1.23-7.26) or white (OR 1.87, 95% CI 0.99-1.27) women and in British Columbia/Yukon Territory than in Alberta (OR 3.31, 95% CI 1.06-10.32), Ontario (OR 3.16, 95% CI 1.08-9.26) or Quebec (OR 3.44, 95% CI 1.09-10.84). Among the 14 vertical HIV transmission events during 2011-2016 (vertical transmission rate 1.0%), maternal HIV infection was diagnosed before the onset of labour in 5 cases, and only 2 women received adequate antenatal combination antiretroviral therapy. INTERPRETATION: Efforts to improve timely access to care, HIV screening and treatment for all women, combined with enhanced resources targeting populations at increased risk for HIV infection, will be needed if vertical HIV transmission is to be eliminated in Canada.

Blood Mitochondrial DNA Content in HIV-Exposed Uninfected Children with Autism Spectrum Disorder.

Long-term outcomes of perinatal exposure to maternal antiretroviral therapy in HIV-exposed uninfected (HEU) children are unknown. However, both HIV antiretroviral therapy and autism spectrum disorder (ASD) have been associated with mitochondrial alterations. Leukocyte mitochondrial DNA (mtDNA) content can serve as a marker for mitochondrial dysfunction. In this cross-sectional, nested case-control study, HEU children with ASD were matched approximately 1:3 on age, sex, and ethnicity to HEU children without ASD, HIV-unexposed uninfected (HUU) controls, and HUU children with ASD. Leukocyte mtDNA content was measured using quantitative PCR. Among 299 HEU in this study, 14 (4.7%) were diagnosed with ASD, which is higher than the general population prevalence estimates. HEU children without ASD and HUU children with ASD had higher mtDNA content than HUU controls. HEU children with ASD had significantly higher mtDNA content than all other study groups. Our results suggest a clear association between elevated leukocyte mtDNA content and both HEU and ASD status. This may implicate mitochondrial dysfunction as a contributor to the high ASD prevalence observed in our cohort.

Leukocyte Telomere Length at Birth and During the Early Life of Children Exposed to but Uninfected With HIV After In Utero Exposure to Antiretrovirals.

Background: Maternal combination antiretroviral therapy (cART) during pregnancy could impact the health of human immunodeficiency virus (HIV)-exposed, HIV-uninfected (HEU) children, because some antiretrovirals cross the placenta and can inhibit telomerase. Our objective was to compare leukocyte telomere length (LTL) in HEU children and HIV-unexposed, HIV-uninfected (HUU) children at birth and in early life and to investigate any relationship with cART exposure. Methods: HEU and HUU children's blood LTL was compared cross-sectionally at birth, and during the first three years of life. Longitudinal HEU LTL dynamics was evaluated over that same period. Results: At birth, the LTL in HEU children (n = 114) was not shorter than that in HUU children (n = 86), but female infants had longer LTL than male infants. Maternal cART (duration or type) showed no association with shorter infant LTL. Among 214 HEU children age- and sex-matched at a 1:1 ratio to HUU children, LTL declined similarly in both groups. In a longitudinal analysis, LTL attrition in HEU children was rapid from birth to 1 year of age and gradual thereafter. Zidovudine prophylaxis did not significantly alter LTL. Conclusions: Our results indicate that from birth to 3 years of age, the LTL in HEU children is not negatively affected by exposure to maternal HIV infection and cART, at least not to the regimens used within this Canadian cohort, a reassuring finding.

Immunogenicity and Safety of the Quadrivalent Human Papillomavirus Vaccine in Girls Living With HIV.

We evaluated quadrivalent human papillomavirus vaccine seroresponses among 35 girls living with HIV (9-13 years of ages) and compared with data on girls without HIV, as part of a subgroup analysis. The quadrivalent human papillomavirus vaccine was safe and well tolerated. However, antibody response was significantly lower in girls living with HIV relative to girls without HIV. HIV virologic suppression predicted better antibody response.

Mobile Text Messaging to Improve Medication Adherence and Viral Load in a Vulnerable Canadian Population Living With Human Immunodeficiency Virus: A Repeated Measures Study.

BACKGROUND: Combination antiretroviral therapy (cART) as treatment for human immunodeficiency virus (HIV) infection is effective and available, but poor medication adherence limits benefits, particularly in vulnerable populations. In a Kenyan randomized controlled trial, a weekly text-messaging intervention (WelTel) improved cART adherence and HIV viral load (VL). Despite growing evidence for short message service (SMS) text-message interventions in HIV care, there is a paucity of data utilizing these interventions in marginalized or female cohorts. OBJECTIVE: This study was undertaken to assess whether the standardized WelTel SMS text-message intervention applied to a vulnerable, predominantly female, population improved cART adherence and VL. METHODS: We conducted a repeated measures study of the WelTel intervention in high-risk HIV-positive persons by measuring change in VL, CD4 count, and self-reported adherence 12 months before and 12 months after the WelTel intervention was introduced. Inclusion criteria included VL ≥200 copies/mL, indication for treatment, and meeting vulnerability criteria. Participants were given a mobile phone with unlimited texting (where required), and weekly check-in text messages were sent for one year from the WelTel computer platform. Clinical data were collected for control and intervention years. Participants were followed by a multidisciplinary team in a clinical setting. Outcomes were assessed using Wilcoxon signed ranks tests for change in CD4 and VL from control year to study end and mixed-effects logistic regressions for change in cART adherence and appointment attendance. A secondary analysis was conducted to assess the effect of response rate on the outcome by modeling final log10 VL by number of responses while controlling for mean log10 VL in the control year. RESULTS: Eighty-five participants enrolled in the study, but 5 withdrew (final N=80). Participants were predominantly female (90%, 72/80) with a variety of vulnerabilities. Mean VL decreased from 1098 copies/mL in the control year to 439 copies/mL at study end (P=.004). Adherence to cART significantly improved (OR 1.14, IQR 1.10-1.18; P<.001), whereas appointment attendance decreased slightly with the intervention (OR 0.81, IQR 0.67-0.99; P=.03). A response was received for 46.57% (1753/3764) of messages sent and 9.62% (362/3764) of text messages sent were replied to with a problem. An outcome analysis examining relationship between reply rate and VL did not meet statistical significance (P=.07), but may be worthy of investigating further in a larger study. CONCLUSIONS: WelTel may be an effective tool for improving cART adherence and reducing VLs among high-risk, vulnerable HIV-positive persons. TRIAL REGISTRATION: Clinicaltrials.gov NCT02603536; https://clinicaltrials.gov/ct2/show/NCT02603536 (Archived by WebCite at http://www.webcitation.org/6qK57zCwv).

Leukocyte telomere length in HIV-infected and HIV-exposed uninfected children: shorter telomeres with uncontrolled HIV viremia.

OBJECTIVES: Nucleoside reverse transcriptase inhibitors (NRTIs) used in HIV antiretroviral therapy can inhibit human telomerase reverse transcriptase. We therefore investigated whether in utero or childhood exposure to NRTIs affects leukocyte telomere length (LTL), a marker of cellular aging. METHODS: In this cross-sectional CARMA cohort study, we investigated factors associated with LTL in HIV-1-infected (HIV(+)) children (n = 94), HIV-1-exposed uninfected (HEU) children who were exposed to antiretroviral therapy (ART) perinatally (n = 177), and HIV-unexposed uninfected (HIV(-)) control children (n = 104) aged 0-19 years. Univariate followed by multivariate linear regression models were used to examine relationships of explanatory variables with LTL for: a) all subjects, b) HIV(+)/HEU children only, and c) HIV(+) children only. RESULTS: After adjusting for age and gender, there was no difference in LTL between the 3 groups, when considering children of all ages together. In multivariate models, older age and male gender were associated with shorter LTL. For the HIV(+) group alone, having a detectable HIV viral load was also strongly associated with shorter LTL (p = 0.007). CONCLUSIONS: In this large study, group rates of LTL attrition were similar for HIV(+), HEU and HIV(-) children. No associations between children's LTL and their perinatal ART exposure or HIV status were seen in linear regression models. However, the association between having a detectable HIV viral load and shorter LTL suggests that uncontrolled HIV viremia rather than duration of ART exposure may be associated with acceleration of blood telomere attrition.

Leukocyte telomere length in HIV-infected pregnant women treated with antiretroviral drugs during pregnancy and their uninfected infants.

OBJECTIVES: HIV disease can lead to accelerated telomere attrition, although certain drugs used as part of antiretroviral therapy (ART) can inhibit telomerase reverse transcriptase activity. This could in turn lead to shorter telomeres. We hypothesized that HIV and ART exposure would be associated with shorter leukocyte telomere length (TL) in exposed mother/infant pairs compared with controls. METHODS: In these retrospective and prospective observational cohort studies, TL was evaluated in peripheral blood leukocytes obtained from HIV-infected pregnant women treated with ART and their uninfected infants, and compared with HIV untreated (retrospective cohort) or HIV mothers and their infants (prospective cohort). RESULTS: In HIV-infected ART-exposed mothers, leukocyte TL was not significantly shorter than that in HIV untreated mothers or HIV controls, nor was their infants' TL significantly different. Cord blood of ART-exposed infants exhibited TL shorter than that from infants born to HIV-negative mothers. Placenta also showed evidence of shorter TL after adjustment for relevant covariates. Factors associated with shorter maternal and infant TL included smoking and the use of drugs of addiction in pregnancy. CONCLUSIONS: These results suggest that maternal HIV infection or exposure to ART has minimal effect on infant leukocyte TL, a reassuring finding. In contrast, tissues that express higher telomerase activity such as umbilical cord blood and placenta appear comparatively more affected by ART. Smoking and the use of drugs of addiction have a negative impact on maternal and infant leukocyte TL, possibly through oxidative telomere damage.

Blood mitochondrial DNA mutations in HIV-infected women and their infants exposed to HAART during pregnancy.

OBJECTIVES: Nucleo(s/t)ide reverse transcriptase inhibitors given to HIV-infected pregnant women to prevent vertical transmission may adversely affect mitochondrial DNA (mtDNA). We hypothesized that HAART-exposed/HIV-uninfected infants may show higher blood mtDNA mutation burden than controls born to HIV-uninfected mothers. METHODS: Blood was collected from in-utero HIV/HAART-exposed infants and controls, as well as from a subset of their mothers. The presence of mtDNA A→C/T→G (AC/TG) mutations was measured by cloning and sequencing D-loop PCR amplicons. Relationships with maternal characteristics were examined. RESULTS: No significant difference was found between the percentage of HIV/HAART-exposed infants with AC/TG mutations (N = 15/57, 26.3%) and controls (N = 10/70, 14.3%) before (P = 0.090) or after controlling for covariates (P = 0.058), although a tendency was observed. However, significantly more HIV/HAART-exposed mothers (N = 18/42, 42.9%) harboured AC/TG mutations compared with controls (N = 7/39, 17.9%) before (P = 0.015) and after (P = 0.012) controlling for covariates. AC/TG mutations were more prevalent in HIV/HAART-exposed mothers than in their infants (N = 42, 42.9 vs. 23.8%, P = 0.033), however, this difference disappeared after controlling for covariates. No difference was seen between control mothers and their infants (N = 39, both 17.9%). In HIV/HAART-exposed mothers, only a detectable HIV plasma viral load near delivery predicted AC/TG mutations. CONCLUSION: Our results suggest that HIV and/or HAART exposure are associated with increased prevalence of AC/TG mtDNA mutations in mothers and show a similar tendency in infants exposed during pregnancy. As accumulation of mtDNA mutations has been linked with aging and age-associated diseases, this may raise concerns in the long term for HIV and HAART-exposed populations.

A national review of vertical HIV transmission.

OBJECTIVES: Prevention of vertical HIV transmission has evolved significantly in Canada over the last two decades. The aim of this analysis is to describe the surveillance programme used, rate of vertical HIV transmission and changing epidemiology of HIV-affected pregnancies in Canada. DESIGN: National perinatal HIV surveillance programme. METHODS: From 1990, annual retrospective data was collected on demographic and clinical characteristics of HIV-infected mothers and their infants referred to 22 participating sites across Canada either before/during pregnancy or within 3 months after delivery. Factors impacting HIV transmission and demographic features were explored. RESULTS: Two thousand, six hundred and ninety-two mother-infant pairs were identified. The overall rate of vertical HIV transmission was 5.2%, declining to 2.9% since 1997. The rate of transmission for mothers who received HAART was 1%, and 0.4% if more than 4 weeks of HAART was given. Forty percent of women delivered by caesarean section, with no difference in transmission rate compared with vaginal delivery for women treated with HAART (1.4 vs. 0.6%, P = 0.129) but significant risk reduction for those who did not receive HAART (3.8 vs. 10.3%, P = 0.016). Black women were the largest group; proportions of black and aboriginal women increased significantly over time (P < 0.001 for both). Heterosexual contact was the most common risk category for maternal infection (65%), followed by injection drug use (IDU) (25%). CONCLUSION: Vertical HIV transmission in Canada has decreased dramatically for women treated with HAART therapy. All pregnant women should be evaluated for HIV infection and programmes expanded to reach vulnerable populations including aboriginal, immigrant and IDU women.