Irene Cheng

Cardiac Effects of Antiretroviral Therapy in HIV-Negative Infants Born to HIV-Positive Mothers: NHLBI CHAART-1 (National Heart, Lung, and Blood Institute Cardiovascular Status of HAART Therapy in HIV-Exposed Infants and Children Cohort Study)

OBJECTIVES The aim of this study was to investigate the possible effects of antiretroviral therapy (ART) in utero on cardiac development and function in human immunodeficiency virus (HIV)-negative children. BACKGROUND ART reduces vertical HIV transmission. Long-term cardiotoxicity after in utero exposure to ART is unknown in children but has occurred in young animals. METHODS Using a prospective multisite cohort study design, echocardiograms taken between birth and 24 months were compared in 2 groups of HIV-negative infants of HIV-positive mothers: 136 infants exposed to ART (ART+) and 216 unexposed infants (ART-). RESULTS Mean left ventricular (LV) mass z-scores were consistently lower in ART+ girls than in ART- girls: differences in mean z-scores were -0.46 at birth (p = 0.005), -1.02 at 6 months (p < 0.001), -0.74 at 12 months (p < 0.001), and -0.79 at 24 months (p < 0.001). Corresponding differences in z-scores for boys were smaller: 0.13 at 1 month (p = 0.42), -0.44 at 6 months (p = 0.01), -0.15 at 12 months (p = 0.37), and -0.21 at 24 months (p = 0.21). Septal wall thickness and LV dimension were smaller than expected in ART+ infants, but LV contractility was consistently about 1 SD higher at all ages (p < 0.001). In ART+ infants, LV fractional shortening was higher than in ART- infants; girls showed a greater difference. CONCLUSIONS Fetal exposure to ART is associated with reduced LV mass, LV dimension, and septal wall thickness z-scores and increased LV fractional shortening and contractility up to age 2 years. These effects are more pronounced in girls than in boys. Fetal ART exposure may impair myocardial growth while improving depressed LV function.

Effect of hard-drug use on CD4 cell percentage, HIV RNA level, and progression to AIDS-defining class C events among HIV-infected women.

In vitro and animal studies suggest that cocaine and heroin increase HIV replication and suppress immune function, whereas epidemiologic studies are inconclusive regarding their effect on HIV infection progression. The authors prospectively examined the association between illicit-drug use and 4 outcome measures (CD4 cell percentage, HIV RNA level, survival to class C diagnosis of HIV infection, and death) in a national cohort of HIV-infected women. Women enrolled between 1989 and 1995 were followed for 5 years and repeatedly interviewed about illicit (“hard”)–drug use. Up to 3 periodic urine screens validated self-reported use. Outcomes were compared between hard-drug users (women using cocaine, heroin, methadone, or injecting drugs) and nonusers, adjusting for age, antiretroviral therapy, number of pregnancies, smoking, and baseline CD4 cell percentage. Of 1148 women, 40% reported baseline hard-drug use during pregnancy. In multivariate analyses, hard-drug use was not associated with change in CD4 cell percentage (P = 0.84), HIV RNA level (P = 0.48), or all-cause mortality (relative hazard = 1.10; 95% confidence interval, 0.61–1.98). Hard-drug users did, however, exhibit a higher risk of developing class C diagnoses (relative hazard = 1.65; 95% confidence interval, 1.00–2.72), especially herpes, pulmonary tuberculosis, and recurrent pneumonia. Hard-drug–using women may have a higher risk for nonfatal opportunistic infections.

Immune responses in adult female volunteers during the bed-rest model of spaceflight: Antibodies and cytokines

BACKGROUND It is unknown whether a prolonged period of bed rest will affect human immune responses, particularly in female subjects. OBJECTIVE We sought to measure immune responses in adult female subjects exposed to prolonged bed rest. METHODS Adult (25-40 years) female volunteers (n = 24) were maintained in a supine (6 degrees tilt) head-down bed-rest (HDBR) position for 60 days: 8 with HDBR only, 8 with HDBR and regular muscular exercise, and 8 with HDBR and dietary protein supplementation. Subjects were immunized with bacteriophage phiX-174. Antibody production and plasma cytokine levels were determined. RESULTS The rate of primary antibody production of the HDBR plus exercise group increased faster (P = .01) and to a higher level versus that of the HDBR-only group (P = .03) and that of the HDBR plus diet group (trend P = .08). The rates of secondary antibody production between the 3 groups were similar, but the level of antibody in the HDBR plus exercise group remained higher versus that in the HDBR-only group (P = .03). Both the HDBR (P = .001) and HDBR plus diet (P = .02) groups had time-related progressive increases in TNF-alpha receptor levels, but the HDBR plus exercise group remained at baseline. The HDBR plus exercise group experienced an acute increase in IL-1 receptor antagonist levels versus the HDBR (P = .02) and the HDBR plus diet (P = .02) groups, with similar increases in RANTES levels. CONCLUSIONS The exercise countermeasure accelerated primary antibody production and increased antibody levels to bacteriophage phiX-174 and also opposed the potentially harmful effects of increased TNF-alpha levels caused by prolonged bed rest, possibly by activating the anti-inflammatory cytokine IL-1 receptor antagonist and the chemotactic factor RANTES.

Postpartum antiretroviral drug resistance in HIV-1-infected women receiving pregnancy-limited antiretroviral therapy.

Background:Pregnancy-limited antiretroviral therapy (PLAT) drastically reduces HIV-1 transmission to the newborn, but may select for antiretroviral drug resistance mutations in mothers. Methods:We evaluated antiretroviral-naive, HIV-1-infected pregnant women who received PLAT between 1998 and 2005, and had 2-month or 6-month postpartum plasma samples available with HIV-1 RNA levels more than 500 copies/ml. Postpartum drug resistance mutation rates were assessed blindly using population sequencing and allele-specific PCR (ASPCR) of the M184V, K103N and D30N mutations. Factors associated with selection of drug resistance mutations were investigated. Results:One hundred and forty-six women were included. All women received zidovudine and lamivudine during pregnancy; 76% also received nelfinavir and 8.2% nevirapine. Resistance data were available from 114 women (78%). Postpartum rates of single-class, dual-class, and triple-class resistance were, respectively, 43, 6.1 and 0% (63.2, 10.5 and 1.7% by ASPCR). In women receiving dual or triple PLAT, respectively, postpartum M184V/I rates were 65% (95% by ASPCR) and 28.7% (51.6% by ASPCR), respectively (P < 0.01). Postpartum nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance rates among women receiving nevirapine were 25% for K103N (37.5% by ASPCR) and 12.5% for Y188C. Protease inhibitor resistance rates in women receiving nelfinavir were 1.1% for D30N (1.1% by ASPCR) and 1.1% for L90M. Dual versus triple PLAT and prolonged zidovudine exposure were associated with selection of M184V. Nevirapine use and length of zidovudine and lamivudine exposure were associated with selection of K103N. Conclusion:PLAT is associated with frequent selection of resistance to drugs with low-genetic barrier. Triple-drug PLAT decreases the odds for M184V selection. Routine postpartum genotypic resistance testing may be useful to guide future treatment decisions in mothers.

Cardiac Effects of Antiretroviral Therapy in HIV-Negative Infants Born to HIV-Positive Mothers

OBJECTIVES The aim of this study was to investigate the possible effects of antiretroviral therapy (ART) in utero on cardiac development and function in human immunodeficiency virus (HIV)-negative children. BACKGROUND ART reduces vertical HIV transmission. Long-term cardiotoxicity after in utero exposure to ART is unknown in children but has occurred in young animals. METHODS Using a prospective multisite cohort study design, echocardiograms taken between birth and 24 months were compared in 2 groups of HIV-negative infants of HIV-positive mothers: 136 infants exposed to ART (ART+) and 216 unexposed infants (ART-). RESULTS Mean left ventricular (LV) mass z-scores were consistently lower in ART+ girls than in ART- girls: differences in mean z-scores were -0.46 at birth (p = 0.005), -1.02 at 6 months (p < 0.001), -0.74 at 12 months (p < 0.001), and -0.79 at 24 months (p < 0.001). Corresponding differences in z-scores for boys were smaller: 0.13 at 1 month (p = 0.42), -0.44 at 6 months (p = 0.01), -0.15 at 12 months (p = 0.37), and -0.21 at 24 months (p = 0.21). Septal wall thickness and LV dimension were smaller than expected in ART+ infants, but LV contractility was consistently about 1 SD higher at all ages (p < 0.001). In ART+ infants, LV fractional shortening was higher than in ART- infants; girls showed a greater difference. CONCLUSIONS Fetal exposure to ART is associated with reduced LV mass, LV dimension, and septal wall thickness z-scores and increased LV fractional shortening and contractility up to age 2 years. These effects are more pronounced in girls than in boys. Fetal ART exposure may impair myocardial growth while improving depressed LV function.

Cardiovascular outcomes of pediatric seroreverters perinatally exposed to HAART: design of a longitudinal clinical study.

Seroreverters (uninfected children of HIV-infected mothers) have exhibited left ventricular (LV) dysfunction. Mitochondrial toxicity associated with in utero or postnatal exposure to highly active antiretroviral therapy (HAART) is a possible mechanism. Adult and animal models have demonstrated associations between LV abnormalities, cardiomyopathy, and components of HAART. Yet outcomes in children are poorly understood. In this study, weexplore HAART-associated LV abnormalities in seroreverters exposed to HAART (n=144) or never exposed (n=252). Subjects are drawn from the Women and Infants Transmission Study and the Pediatric Pulmonary and Cardiovascular Complications of HIV Study, respectively. Data include (1) echocardiographic studies of LV structure and function and (2) serologic cardiac biomarkers (cardiac troponin, probrain natriuretic peptide, high-sensitivity C reactive protein), both collected during the first month of life, and again, at 6, 12, 24, 36, and 48 months postnatally. Planned analyses, include several regression models. At this time, we have access to data for all 252 unexposed children, and 53 exposed subjects are enrolled. The cohorts are similar in terms of gender and race and the recruited subjects are representative of all eligible subjects in terms of exposure to HAART. Recruitment will continue into 2006.

High prevalence of primary lamivudine and nelfinavir resistance in HIV-1-infected pregnant women in the United States, 1998-2004.

Using a highly sensitive allele-specific polymerase chain reaction assay we detected the M184V mutation for lamivudine resistance in plasma from 9.4% of HIV-1-infected pregnant women enrolled in the Women and Infant Transmission Study between 1998 and 2004. The prevalence of nelfinavir resistance (D30N) was 6.3%. These results suggest a high prevalence of primary lamivudine and nelfinavir resistance among HIV-1-infected pregnant women in the United States, and support routine genotypic resistance testing before initiating mother-to-child-transmission prophylaxis.

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 1 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 equal to or less than 30 months and the McCarthy Scales of Childrens 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 (Δβ) and intercepts (Δα) 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.

Cardiac Effects of Antiretroviral Therapy in HIV-Negative Infants Born to HIV-Positive Mothers: The NHLBI CHAART-1 Cohort Study

OBJECTIVES The aim of this study was to investigate the possible effects of antiretroviral therapy (ART) in utero on cardiac development and function in human immunodeficiency virus (HIV)-negative children. BACKGROUND ART reduces vertical HIV transmission. Long-term cardiotoxicity after in utero exposure to ART is unknown in children but has occurred in young animals. METHODS Using a prospective multisite cohort study design, echocardiograms taken between birth and 24 months were compared in 2 groups of HIV-negative infants of HIV-positive mothers: 136 infants exposed to ART (ART+) and 216 unexposed infants (ART-). RESULTS Mean left ventricular (LV) mass z-scores were consistently lower in ART+ girls than in ART- girls: differences in mean z-scores were -0.46 at birth (p = 0.005), -1.02 at 6 months (p < 0.001), -0.74 at 12 months (p < 0.001), and -0.79 at 24 months (p < 0.001). Corresponding differences in z-scores for boys were smaller: 0.13 at 1 month (p = 0.42), -0.44 at 6 months (p = 0.01), -0.15 at 12 months (p = 0.37), and -0.21 at 24 months (p = 0.21). Septal wall thickness and LV dimension were smaller than expected in ART+ infants, but LV contractility was consistently about 1 SD higher at all ages (p < 0.001). In ART+ infants, LV fractional shortening was higher than in ART- infants; girls showed a greater difference. CONCLUSIONS Fetal exposure to ART is associated with reduced LV mass, LV dimension, and septal wall thickness z-scores and increased LV fractional shortening and contractility up to age 2 years. These effects are more pronounced in girls than in boys. Fetal ART exposure may impair myocardial growth while improving depressed LV function.