Possible mitochondrial dysfunction and its association with antiretroviral therapy use in children perinatally infected with HIV

Associations of FGF21 and GDF15 with mitochondrial dysfunction in children living with perinatally-acquired HIV: A cross-sectional evaluation of pediatric AIDS clinical trials group 219/219C

BACKGROUND

In persons living with HIV, mitochondrial disease (MD) is difficult to diagnose, as clinical signs are non-specific with inconsistent patterns. Fibroblast growth factor 21 (FGF21) and growth differentiation factor 15 (GDF15) are mitokines elevated in MD patients without HIV, and associated with cardiometabolic comorbidities in adults living with HIV. We assessed relationships of these biomarkers with MD in children living with perinatally-acquired HIV infection (CPHIV).

SETTING

Cross-sectional study of CPHIV from Pediatric ACTG 219/219C classified by Mitochondrial Disease Criteria (MDC) that defines scores 2-4 as "possible" MD.

METHODS

Each case with MDC equaling 4 (MDC4; n = 23) was matched to one randomly selected control displaying no MDC (MDC0; n = 23) based on calendar date. Unmatched cases with MDC equaling 3 (MDC3; n = 71) were also assessed. Plasma samples proximal to diagnoses were assayed by ELISA. Mitokine distributions were compared using Wilcoxon tests, Spearman correlations were calculated, and associations with MD status were assessed by conditional logistic regression.

RESULTS

Median FGF21 and GDF15 concentrations, respectively, were highest in MDC4 (143.9 and 1441.1 pg/mL), then MDC3 (104.0 and 726.5 pg/mL), and lowest in controls (89.4 and 484.7 pg/mL). Distributions of FGF21 (paired Wilcoxon rank sum p = 0.002) and GDF15 (paired Wilcoxon rank sum p<0.001) differed in MDC4 vs MDC0. Mitokine concentrations were correlated across all participants (r = 0.33; p<0.001). Unadjusted odds ratios of being MDC4 vs MDC0 were 5.2 [95% confidence interval (CI): 1.06-25.92] for FGF21 and 3.5 (95%CI: 1.19-10.25) for GDF15. Relationships persisted after covariate adjustments.

CONCLUSION

FGF21 and GDF15 levels may be useful biomarkers to screen for CPHIV with mitochondrial dysfunction.

Perinatally acquired HIV infection is associated with abnormal blood mitochondrial function during childhood/adolescence

OBJECTIVE

We assessed differences in mitochondrial function between youth living with perinatal HIV (YPHIV) and youth perinatally HIV-exposed but uninfected (YPHEU).

DESIGN

Cross-sectional analysis.

METHODS

We measured lactate and pyruvate values, as well as mitochondrial Complex I and Complex IV activity in peripheral blood mononuclear cells. Logistic or linear regression models were fit, as appropriate, to assess the association between PHIV status and each mitochondrial parameter, adjusted for confounders. We introduced interaction terms to assess effect modification of PHIV status on the relationship between anthropometric factors and each mitochondrial parameter. Among YPHIV, similar regression models were fit to assess the relationship between HIV-associated factors and each mitochondrial outcome.

RESULTS

A total of 243 YPHIV and 118 YPHEU were compared. On average, YPHIV had higher lactate/pyruvate ratio (β: 7.511, 95% confidence interval [95% CI]: 0.402, 14.620) and Complex IV activity (β: 0.037, 95% CI: 0.002, 0.072) compared to YPHEU, adjusted for confounders. Among YPHIV, body mass index Z score (BMIZ) and Complex I activity were inversely associated, whereas, among YPHEU, there was a positive association (β for interaction: -0.048, P = 0.003). Among YPHIV, current (β: -0.789, 95% CI: -1.174, -0.404) and nadir CD4+% (β: -0.605, 95% CI: -1.086, -0.125) were inversely associated with lactate/pyruvate ratio; higher current (4.491, 95% CI: 0.754, 8.229) and peak (7.978, 95% CI: 1.499, 14.457) HIV RNA levels were positively associated with lactate/pyruvate ratio in adjusted models.

CONCLUSIONS

Mitochondrial function and substrate utilization appear perturbed in YPHIV compared to YPHEU. Increasing immunosuppression and viremia are associated with mitochondrial dysfunction among YPHIV.

Mitochondrial Dysfunction and Insulin Resistance in Pubertal Youth Living with Perinatally Acquired HIV

Mitochondrial dysfunction (MD) is linked to cardiometabolic complications, such as obesity and insulin resistance (IR), the frequencies of which are higher in adults living with HIV infection and receiving combination antiretroviral therapies (ARV). ARV-treated youth living with perinatally acquired HIV infection (YLPHIV) may be especially susceptible to IR due to long-term exposure to both factors. Medical histories, fasting blood chemistry panels, and mitochondrial function in banked peripheral blood mononuclear cells (PBMCs) were assessed in eligible YLPHIV from the Pediatric HIV/AIDS Cohort Study (PHACS)/Adolescent Master Protocol (AMP) Mitochondrial Determinants Component cohort, stratified by Homeostatic Model Assessment of IR (HOMA-IR) score: case (score ≥4, n = 39) or control (score <4, n = 105). PBMCs were sources for mitochondrial (mt) DNA copies/cell; mtRNA transcript levels of oxidative phosphorylation (OXPHOS) subunits NADH dehydrogenases 1 and 6, and cytochrome B; and enzymatic activities of OXPHOS Complexes I (CI) and IV (CIV). Logistic regression models were fit to estimate the odds of IR case diagnosis, adjusted for sex, race/ethnicity, body mass index (BMI) z-score, and Tanner stage. IR cases were similar to controls by age, sex, and race/ethnicity. Cases had higher median levels of peak HIV viral load, lactate, pyruvate, triglycerides, and BMI z-scores. OXPHOS CI enzymatic activity was lower in cases (log₁₀ 1.62 vs. 1.70) and inversely correlated with HOMA-IR score (r = -0.157, p = .061), but did not associate with IR in adjusted models. Fully adjusted models indicated associations of nadir CD4% [odds ratio (OR) = 0.95, 95% confidence intervals (CIs) = 0.90-1.00] or peak HIV load (OR = 3.48, 95% CIs = 1.70-10.79) with IR. IR in YLPHIV was strongly associated with morphometrics, but early virologic and immunologic factors may also influence MD.

Cellular stress responses and dysfunctional Mitochondrial-cellular senescence, and therapeutics in chronic respiratory diseases

The abnormal inflammatory responses due to the lung tissue damage and ineffective repair/resolution in response to the inhaled toxicants result in the pathological changes associated with chronic respiratory diseases. Investigation of such pathophysiological mechanisms provides the opportunity to develop the molecular phenotype-specific diagnostic assays and could help in designing the personalized medicine-based therapeutic approaches against these prevalent diseases. As the central hubs of cell metabolism and energetics, mitochondria integrate cellular responses and interorganellar signaling pathways to maintain cellular and extracellular redox status and the cellular senescence that dictate the lung tissue responses. Specifically, as observed in chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis, the mitochondria-endoplasmic reticulum (ER) crosstalk is disrupted by the inhaled toxicants such as the combustible and emerging electronic nicotine-delivery system (ENDS) tobacco products. Thus, the recent research efforts have focused on understanding how the mitochondria-ER dysfunctions and oxidative stress responses can be targeted to improve inflammatory and cellular dysfunctions associated with these pathologic illnesses that are exacerbated by viral infections. The present review assesses the importance of these redox signaling and cellular senescence pathways that describe the role of mitochondria and ER on the development and function of lung epithelial responses, highlighting the cause and effect associations that reflect the disease pathogenesis and possible intervention strategies.

Mitochondrial Impairment in Well-Suppressed Children with Perinatal HIV-Infection on Antiretroviral Therapy

Mitochondrial impairment is reported in HIV-infected children receiving antiretroviral therapy (ART), as well as those naive to ART. Whether mitochondrial function recovers with early initiation of ART and sustained viral suppression on long-term ART is unclear. In this study, we evaluate mitochondrial markers in well-suppressed perinatally HIV-infected children initiated on ART early in life. We selected a cross-sectional sample of 120 HIV-infected children with viral load <400 copies/mL and 60 age-matched uninfected children (22 HIV-exposed uninfected) enrolled in a cohort study in Johannesburg, South Africa. Complex IV (CIV) and citrate synthase (CS) activity were measured by spectrophotometry. Mitochondrial DNA (mtDNA) content relative to nuclear DNA (nDNA) was measured by quantitative real-time polymerase chain reaction and expressed as copies/nDNA. Mitochondrial markers were impaired in HIV-infected children, including lower mean CIV activities [1.76 vs. 1.40 optical densities (OD)/min], higher risk of a CIV/CS ratio ≤0.22 (third quartile; odds ratio = 3.03, 95% confidence interval: 1.38-6.66), and lower mtDNA content. Children with shorter versus longer ART duration (<6.3 vs. ≥6.3 years) had lower means of CIV activity (1.22-1.58 OD/min) and mtDNA content (386-907 copies/nDNA). There were no differences in mitochondrial markers between children who started ART earlier (<6 months) or later (6-24 months). CIV activity was impaired in children with lower height-for-age Z-scores (HAZs). Despite early treatment and prolonged viral suppression, HIV-infected children had detectable mitochondrial impairment, particularly among those with stunted growth. Further study is required to determine if continued treatment will lead to full recovery of mitochondrial function in HIV-infected children.

Larger Subcortical Gray Matter Structures and Smaller Corpora Callosa at Age 5 Years in HIV Infected Children on Early ART

Sub-Saharan Africa is home to 90% of HIV infected (HIV+) children. Since the advent of antiretroviral therapy (ART), HIV/AIDS has transitioned to a chronic condition where central nervous system (CNS) damage may be ongoing. Although, most guidelines recommend early ART to reduce CNS viral reservoirs, the brain may be more vulnerable to potential neurotoxic effects of ART during the rapid development phase in the first years of life. Here we investigate differences in subcortical volumes between 5-year-old HIV+ children who received early ART (before age 18 months) and uninfected children using manual tracing of Magnetic Resonance Images. Participants included 61 Xhosa children (43 HIV+/18 uninfected, mean age = 5.4 ± 0.3 years, 25 male) from the children with HIV early antiretroviral (CHER) trial; 27 children initiated ART before 12 weeks of age (ART-Before12Wks) and 16 after 12 weeks (ART-After12Wks). Structural images were acquired on a 3T Allegra MRI in Cape Town and manually traced using MultiTracer. Volumetric group differences (HIV+ vs. uninfected; ART-Before12Wks vs. ART-After12Wks) were examined for the caudate, nucleus accumbens (NA), putamen (Pu), globus pallidus (GP), and corpus callosum (CC), as well as associations within infected children of structure volumes with age at ART initiation and CD4/CD8 as a proxy for immune health. HIV+ children had significantly larger NA and Pu volumes bilaterally and left GP volumes than controls, whilst CC was smaller. Bilateral Pu was larger in both treatment groups compared to controls, while left GP and bilateral NA were enlarged only in ART-After12Wks children. CC was smaller in both treatment groups compared to controls, and smaller in ART-After12Wks compared to ART-Before12Wks. Within infected children, delayed ART initiation was associated with larger Pu volumes, effects that remained significant when controlling for sex and duration of treatment interruption (left β = 0.447, p = 0.005; right β = 0.325, p = 0.051), and lower CD4/CD8 with larger caudates controlling for sex (left β = -0.471, p = 0.002; right β = -0.440, p = 0.003). Volumetric differences were greater in children who initiated ART after 12 weeks. Results suggest damage is ongoing despite early ART and viral load suppression; however, earlier treatment is neuroprotective.

Dispelling myths and focusing on notable concepts in HIV pathogenesis

Since the discovery of HIV over three decades ago, major efforts have been made to control and perhaps eliminate HIV infection worldwide. During these studies, certain myths or misconceptions about this infectious disease have been emphasized and other potentially beneficial concepts have received less attention. A true long-term solution to HIV infection merits an appreciation of alternative ideas and findings that could be beneficial in the ultimate control of HIV/AIDS. Here, I discuss six issues and call for more attention to the science of HIV and well-designed clinical trials.

Tolerance of the newborn to antiretroviral drug exposure in utero

INTRODUCTION

The prevention of mother-to-child HIV-1 transmission by antiretroviral drug treatment is remarkably effective. The risk of transmission to the child is now almost zero for women optimally treated during pregnancy. The rapid expansion of this prophylactic treatment has led the World Health Organization to aspire to the virtual elimination of mother-to-child transmission and pediatric AIDS over the next few years. In 2014, more than 900,000 women worldwide were treated with antiretroviral drugs during pregnancy. The issue of fetal and neonatal antiretroviral drug tolerance is therefore extremely important.

AREAS COVERED

This review focuses on the possible impact of in utero exposure to antiretroviral drug on newborn health. To restrict analysis to this period is justified by the specificities of transplacental drug exposure and fetal vulnerability. Relevant data are available from trials and observational cohorts. The significance of various bio-markers detectable at birth is still unresolved, but merits a careful evaluation. Long-term assessment is associated with various logistical difficulties.

EXPERT OPINION

The health of 'exposed but not infected' children poses no major problem in the immense majority of cases, but a series of biological, clinical and imaging-based warning signs have emerged indicating the need for careful attention to be paid to this issue. Some effects that are straightforward to manage in industrialized countries may have more severe consequences in countries in which access to effective healthcare is limited. Nucleoside/nucleotide analogs are potentially genotoxic to mitochondrial and nuclear DNA, and the principal question to be addressed concerns their potential long-term effects.

Hearing loss among HIV-seropositive and HIV-seronegative men and women

IMPORTANCE

Age-related hearing loss affects quality of life. Data on hearing loss among aging human immunodeficiency virus-seropositive (HIV+) adults are limited.

OBJECTIVE

To evaluate pure-tone hearing thresholds among HIV+ and HIV-seronegative (HIV-) adults and to determine whether HIV disease variables and antiretroviral therapy are associated with pure-tone threshold levels.

DESIGN, SETTING, AND PARTICIPANTS

A total of 262 men (117 HIV+) from the Baltimore, Maryland/Washington, DC, site of the Multicenter AIDS Cohort Study and 134 women (105 HIV+) from the Washington, DC, site of the Women's Interagency HIV Study participated. Pure-tone air conduction thresholds were collected in a sound-treated room for each ear at frequencies from 250 through 8000 Hz. Linear mixed regression models tested the effect of HIV on hearing after adjustment for age, sex, race, and noise exposure history.

MAIN OUTCOMES AND MEASURES

Low-frequency pure-tone average (LPTA) at 250, 500, 1000, and 2000 Hz and high-frequency PTA (HPTA) at 3000, 4000, 6000, and 8000 Hz. Differential HIV effects for LPTA and HPTA and better/worse ear were also examined. CD4⁺ and CD8⁺ T-cell counts, log10 plasma HIV RNA concentrations, receipt of AIDS diagnosis, and cumulative duration of antiretroviral therapy were included in the models for HIV+ participants only.

RESULTS

HPTA and LPTA were significantly higher (18%: estimated ratio, 1.18 [95% CI, 1.02-1.36]; P = .02; and 12%: estimated ratio, 1.12 [95% CI, 1.00-1.26]; P = .05, respectively) for HIV+ participants compared with HIV- participants for the better ear. The direction of the effect was consistent across both the better and worse ears. There were no significant associations between HIV disease variables or treatment variables and LPTA or HPTA.

CONCLUSIONS AND RELEVANCE

The HIV+ adults had significantly poorer lower-frequency and higher-frequency hearing than HIV- adults. High-frequency hearing loss is consistent with an accelerated aging (presbycusis); low-frequency hearing loss in middle age is unexpected. Because some vowels and consonants have predominantly low-frequency acoustic energy, poor low-frequency hearing may impair communication in HIV+ individuals.

Cardiac effects of in-utero exposure to antiretroviral therapy in HIV-uninfected children born to HIV-infected mothers

OBJECTIVES

We evaluated the potential cardiac effects of in-utero exposures to antiretroviral drugs in HIV-exposed but uninfected (HEU) children.

DESIGN AND METHODS

We compared echocardiographic parameters of left ventricular function (ejection fraction, fractional shortening, and stress-velocity index) and structure (left ventricular dimension, posterior wall/septal thickness, mass, thickness-to-dimension ratio, and wall stress) (expressed as Z-scores to account for age and body surface area) between HEU and HIV-unexposed cohorts from the Pediatric HIV/AIDS Cohort Study's Surveillance Monitoring for ART Toxicities study. Within the HEU group, we investigated the associations between the echocardiographic Z-scores and in-utero exposures to maternal antiretroviral drugs.

RESULTS

There were no significant differences in echocardiographic Z-scores between 417 HEU and 98 HIV-unexposed children aged 2-7 years. Restricting the analysis to HEU children, first-trimester exposures to combination antiretroviral therapy (a regimen including at least three antiretroviral drugs) and to certain specific antiretroviral drugs were associated with significantly lower stress-velocity Z-scores (mean decreases of 0.22-0.40 SDs). Exposure to combination antiretroviral therapy was also associated with lower left ventricular dimension Z-scores (mean decrease of 0.44 SD). First-trimester exposure to combination antiretroviral therapy was associated with higher mean left ventricular posterior wall thickness and lower mean left ventricular wall stress Z-scores.

CONCLUSION

There was no evidence of significant cardiac toxicity of perinatal combination antiretroviral therapy exposure in HEU children. Subclinical differences in left ventricular structure and function with specific in-utero antiretroviral exposures indicate the need for a longitudinal cardiac study in HEU children to assess long-term cardiac risk and cardiac monitoring recommendations.

Neurocognitive functioning in a Romanian cohort of young adults with parenterally-acquired HIV-infection during childhood

The Romanian cohort can provide valuable information about the effect of chronic HIV-infection and exposure to combined antiretroviral therapy (cART) on the developing brain, based on its unique characteristics: young adults infected parenterally with HIV clade F in the late 1980s and exposed to cART for a decade. We conducted a prospective study using a neuropsychological test battery validated in other international HIV cohorts, in order to evaluate the rate and severity of neurocognitive impairment in a group of young Romanian adults. The 49 HIV-infected (HIV+) participants and the 20 HIV negative (HIV-) controls were similar for age and gender, although the HIV- group tended to be more educated. We found higher cognitive impairment prevalence in the HIV+ group (59.1 %) versus the HIV- group (10 %), and the impairment rate remained significantly higher even when the groups were matched based on the educational level (38.7 % for the HIV+ group vs. 10.0 % for the HIV- controls; p = 0.025). The nadir CD4 count was <200 in 71.4 % of patients, but at the time of neurocognitive assessment, 89.5 % of patients had normal immunological status and 81.8 % undetectable HIV load. Among the HIV-impaired group, 26 % of the participants had syndromic impairment while the other 74 % had asymptomatic neurocognitive impairment. We found a high prevalence of neurocognitive dysfunction in the Romanian young adults growing-up with HIV. The greatest HIV-related cognitive deficits were in the domains of executive and motor functioning, consistent with a frontosubcortical pattern.

Comparison of auditory brainstem response in HIV-1 exposed and unexposed newborns and correlation with the maternal viral load and CD4+ cell counts

OBJECTIVE

The effects of maternal HIV infection and antiretroviral therapy on hearing of HIV-exposed newborns in sub-Saharan Africa have not been investigated. We determined the prevalence of sensorineural hearing loss among HIV-exposed newborns and the association between the hearing threshold and maternal and newborn parameters.

DESIGN

A cohort audiometric study of newborns between October 2012 and April 2013.

SETTINGS

A secondary and tertiary hospital-based study.

PARTICIPANTS

Consecutive 126 HIV-exposed and 121 HIV-unexposed newborns.

INTERVENTION

Hearing screening of the newborns was done with Auditory Brainstem Response and compared with maternal HAART, CD4 cell counts, RNA viral loads and newborn CD4 cell count percentage.

MAIN OUTCOME MEASURE

Hearing threshold levels of both groups were measured and analysed.

RESULTS

Around 11.1% of HIV-exposed and 6.6% of unexposed newborns had hearing impairment (P = 0.2214). About 6.4% of HIV-exposed and 2.5% HIV-unexposed newborns had hearing threshold of more than 20 dBHL (P = 0.1578). There was no significant association between the hearing thresholds of HIV-exposed newborns and maternal CD4 cell counts (P = 0.059) but there was with maternal viral load (P = 0.034). There was significant difference between the hearing thresholds of HIV-exposed newborns with CD4% of 25 or less and more than 25. This study showed significant difference in the hearing of the 119 HAART-exposed newborns and seven unexposed newborns [P = 0.002; risk ratio, 0.13 (0.05-0.32)].

CONCLUSION

There was a trend towards more hearing loss in HIV-exposed newborns. However, hearing thresholds increase with increasing mothers' viral load. The background information supports the need for further studies on the role of in-utero exposure to HIV and HAART in newborn hearing loss.

Short communication: The relationship between mitochondrial dysfunction and insulin resistance in HIV-infected children receiving antiretroviral therapy

Mitochondrial abnormalities may lead to metabolic complications in HIV-infected children who have been receiving long-term antiretroviral treatment. We conducted a matched, case-control study comparing 21 HIV-infected children with insulin resistance (cases) to 21 HIV-infected children without insulin resistance (controls) to assess differences in mitochondrial DNA (mtDNA) copies/cell and oxidative phosphorylation NADH dehydrogenase (C1) and cytochrome c oxidase (C4) enzyme activities in peripheral blood mononuclear cells. MtDNA copies/cell tended to be lower in cases, and fasting serum glucose levels were inversely and significantly correlated with C1 enzyme activity, more so in cases. Larger pediatric studies should evaluate mitochondrial etiologies of insulin resistance and determine the role of antiretroviral therapies or HIV infection on mitochondrial dysfunction.

Cardiac effects in perinatally HIV-infected and HIV-exposed but uninfected children and adolescents: a view from the United States of America

Introduction

Human immunodeficiency virus (HIV) infection is a primary cause of acquired heart disease, particularly of accelerated atherosclerosis, symptomatic heart failure, and pulmonary arterial hypertension. Cardiac complications often occur in late-stage HIV infections as prolonged viral infection is becoming more relevant as longevity improves. Thus, multi-agent HIV therapies that help sustain life may also increase the risk of cardiovascular events and accelerated atherosclerosis.

Discussion

Before highly active antiretroviral therapy (HAART), the two-to-five-year incidence of symptomatic heart failure ranged from 4 to 28% in HIV patients. Patients both before and after HAART also frequently have asymptomatic abnormalities in cardiovascular structure. Echocardiographic measurements indicate left ventricular (LV) systolic dysfunction in 18%, LV hypertrophy in 6.5%, and left atrial dilation in 40% of patients followed on HAART therapy. Diastolic dysfunction is also common in long-term survivors of HIV infection. Accelerated atherosclerosis has been found in HIV-infected young adults and children without traditional coronary risk factors. Infective endocarditis, although rare in children, has high mortality in late-stage AIDS patients with poor nutritional status and severely compromised immune systems. Although lymphomas have been found in HIV-infected children, the incidence is low and cardiac malignancy is rare. Rates of congenital cardiovascular malformations range from 5.6 to 8.9% in cohorts of HIV-uninfected and HIV-infected children with HIV-infected mothers. In non-HIV-infected infants born to HIV-infected mothers, foetal exposure to ART is associated with reduced LV dimension, LV mass, and septal wall thickness and with higher LV fractional shortening and contractility during the first two years of life.

Conclusions

Routine, systematic, and comprehensive cardiac evaluation, including a thorough history and directed laboratory assays, is essential for the care of HIV-infected adults and children as cardiovascular illness has become a part of care for long-term survivors of HIV infection. The history should include traditional risk factors for atherosclerosis, prior opportunistic infections, environmental exposures, and therapeutic and illicit drug use. Laboratory tests should include a lipid profile, fasting glucose, and HIV viral load. Asymptomatic cardiac disease related to HIV can be fatal, and secondary effects of HIV infection often disguise cardiac symptoms, so systematic echocardiographic monitoring is warranted.

Physical fitness in children infected with the human immunodeficiency virus: associations with highly active antiretroviral therapy

Obesity, sedentary lifestyles, and antiretroviral therapies may predispose HIV-infected children to poor physical fitness. Estimated peak oxygen consumption (VO(2) peak), maximal strength and endurance, and flexibility were measured in HIV-infected and uninfected children. Among HIV-infected children, anthropometric and HIV disease-specific factors were evaluated to determine their association with VO(2) peak. Forty-five HIV-infected children (mean age 16.1 years) and 36 uninfected children (mean age 13.5 years) participated in the study. In HIV-infected subjects, median viral load was 980 copies/ml (IQR 200-11,000 copies/ml), CD4% was 28% (IQR 15-35%), and 82% were on highly active antiretroviral therapy (HAART). Compared to uninfected children, after adjusting for age, sex, race, body fat, and siblingship, HIV-infected children had lower VO(2) peak (25.92 vs. 30.90 ml/kg/min, p<0.0001), flexibility (23.71% vs. 46.09%, p=0.0003), and lower-extremity strength-to-weight ratio (0.79 vs. 1.10 kg lifted/kg of body weight, p=0.002). Among the HIV-infected children, a multivariable analysis adjusting for age, sex, race, percent body fat, and viral load showed VO(2) peak was 0.30 ml/kg/min lower per unit increase in percent body fat (p<0.0001) and VO(2) peak (SE) decreased 29.45 (± 1 .62), 28.70 (± 1.87), and 24.09 (± 0.75) ml/kg/min across HAART exposure categories of no exposure, <60, and ≥ 60 months, respectively (p<0.0001). HIV-infected children had, in general, lower measures of fitness compared to uninfected children. Factors negatively associated with VO(2) peak in HIV-infected children include higher body fat and duration of HAART ≥ 60 months. Future studies that elucidate the understanding of these differences and mechanisms of decreased physical fitness should be pursued.

Performance of Clinical Criteria for Screening of Possible Antiretroviral Related Mitochondrial Toxicity in HIV-Infected Children in Accra

Mitochondrial damage is implicated in highly active antiretroviral therapy (HAART) toxicity. HIV infection also causes mitochondrial toxicity (MT). Differentiating between the two is critical for HIV management. Our objective was to test the utility of the Mitochondrial Disease Criteria (MDC) and the Enquête Périnatale Française (EPF) to screen for possible HAART related MT in HIV-infected children in Ghana. The EPF and MDC are compilations of clinical symptoms, or criteria, of MT: a (+) score indicates possible MT. We applied these criteria retrospectively to 403 charts of HIV-infected children. Of those studied, 331/403 received HAART. Comparing HAART exposed and HAART naïve children, the difference in EPF score, but not MDC, approached significance (P = 0.1). Young age at HIV diagnosis or at HAART initiation was associated with (+) EPF (P ≤ 0.01). Adherence to HAART trended toward an association with (+) EPF (P = 0.09). Exposure to nevirapine, abacavir, or didanosine increased risk of (+) EPF (OR = 3.55 (CI = 1.99-6.33), 4.76 (2.39-9.43), 4.93 (1.29-18.87)). Neither EPF nor MDC identified a significant difference between HAART exposed or naïve children regarding possible MT. However, as indicators of HAART exposure are associated with (+) EPF, it may be a candidate for prospective study of possible HAART related MT in resource-poor settings.

The Use of the Medical Dictionary for Regulatory Activities in the Identification of Mitochondrial Dysfunction in HIV-Infected Children

OBJECTIVE

To demonstrate the utility of a medical terminology-based method for identifying cases of possible mitochondrial dysfunction (MD) in a large cohort of youths with perinatal HIV infection and to describe the scoring algorithms.

METHODS

Medical Dictionary for Regulatory Activities (MedDRA)^® version 6 terminology was used to query clinical criteria for mitochondrial dysfunction by two published classifications, the Enquête Périnatale Française (EPF) and the Mitochondrial Disease Classification (MDC). Data from 2,931 participants with perinatal HIV infection on PACTG 219/219C were analyzed. Data were qualified for severity and persistence, after which clinical reviews of MedDRA-coded and other study data were performed.

RESULTS

Of 14,000 data records captured by the EPF MedDRA query, there were 3,331 singular events. Of 18,000 captured by the MDC query, there were 3,841 events. Ten clinicians blindly reviewed non MedDRA-coded supporting data for 15 separate clinical conditions. We used the Statistical Analysis System (SAS) language to code scoring algorithms. 768 participants (26%) met the EPF case definition of possible MD; 694 (24%) met the MDC case definition, and 480 (16%) met both definitions.

LIMITATIONS

Subjective application of codes could have affected our results. MedDRA terminology does not include indicators of severity or persistence. Version 6.0 of MedDRA did not include Standard MedDRA Queries, which would have reduced the time needed to map MedDRA terms to EPF and MDC criteria.

CONCLUSION

Together with a computer-coded scoring algorithm, MedDRA terminology enabled identification of potential MD based on clinical data from almost 3000 children with substantially less effort than a case by case review. The article is accessible to readers with a background in statistical hypothesis testing. An exposure to public health issues is useful but not strictly necessary.

Hearing loss in perinatally HIV-infected and HIV-exposed but uninfected children and adolescents

BACKGROUND

Little is known about hearing loss in children with HIV infection (HIV+). We examined the prevalence of hearing loss in perinatally HIV+ and HIV-exposed but uninfected (HEU) children, compared these with the percentage with hearing loss in the general population and evaluated possible risk factors for hearing loss in HIV+ and HEU children.

METHODS

Audiometric examinations were completed in children who met any prespecified criteria for possible hearing loss. The hearing examination consisted of a tympanogram in each ear and pure-tone air-conduction threshold testing from 500 through 4000 Hz. Hearing loss was defined as the pure-tone average over these frequencies ≥ 20 dB hearing level. The associations of demographic variables, parent/caregiver, HIV disease and HIV treatment with hearing loss were evaluated with univariate and multivariable logistic regression models.

RESULTS

Hearing testing was completed in 231 children (145 HIV+ and 86 HEU). Hearing loss occurred in 20.0% of HIV+ children and 10.5% of HEU children. After adjusting for caregiver education level, HIV infection was associated with increased odds of hearing loss (adjusted odds ratio = 2.13, 95% confidence interval: 0.95-4.76, P = 0.07). Among HIV+ children, those with a Centers for Disease Control and Prevention class C diagnosis had over twice the odds of hearing loss (adjusted odds ratio = 2.47, 95% confidence interval: 1.04-5.87, P = 0.04). The prevalence of hearing loss was higher in both HIV+ and HEU children compared with National Health and Nutrition Examination Survey III children.

CONCLUSIONS

Hearing loss was more common in both HIV+ and HEU children than in children from a US population sample. More advanced HIV illness increased the risk of hearing loss in HIV+ children.

Language impairment in children perinatally infected with HIV compared to children who were HIV-exposed and uninfected

OBJECTIVE

To investigate the risk for language impairment (LI) in children perinatally infected or exposed to HIV.

METHODS

We evaluated the prevalence of LI in 7- to 16-year-old children with perinatal HIV infection (HIV+) compared with HIV-exposed and uninfected children, using a comprehensive standardized language test (Clinical Evaluation of Language Functioning-Fourth Edition [CELF-4]). LI was classified as primary LI (Pri-LI) (monolingual English exposure and no cognitive or hearing impairment), concurrent LI (Con-LI) (cognitive or hearing impairment), or no LI. Associations of demographic, caregiver, HIV disease, and antiretroviral treatment factors with LI category were evaluated using univariate and multivariable logistic regression models.

RESULTS

Of the 468 children with language assessments, 184 (39%) had LI. No difference was observed by HIV infection status for overall LI or for Pri-LI or Con-LI; mean (SD) CELF-4 scores were 88.5 (18.4) for HIV+ versus 87.5 (17.9) for HIV-exposed and uninfected children. After adjustment, black children had higher odds of Pri-LI versus no LI (adjusted odds ratio [aOR] = 2.43, p = .03). Children who were black, Hispanic, had a caregiver with low education or low intelligence quotient, or a nonbiological parent as caregiver had higher odds of Con-LI versus no LI. Among HIV+ children, viral load >400 copies/mL (aOR = 3.04, p < .001), Centers for Disease Control and Prevention Class C (aOR = 2.19, p = .02), and antiretroviral treatment initiation <6 months of age (aOR = 2.12, p = .02) were associated with higher odds of Con-LI versus no LI.

CONCLUSIONS

Children perinatally exposed to HIV are at high risk for LI, but such risk was not increased for youth with HIV. Risk factors differed for Pri-LI and Con-LI.

HIV infection, inflammation, immunosenescence, and aging

Although antiretroviral therapy for HIV infection prevents AIDS-related complications and prolongs life, it does not fully restore health. Long-term treated patients remain at higher than expected risk for a number of complications typically associated with aging, including cardiovascular disease, cancer, osteoporosis, and other end-organ diseases. The potential effect of HIV on health is perhaps most clearly exhibited by a number of immunologic abnormalities that persist despite effective suppression of HIV replication. These changes are consistent with some of the changes to the adaptive immune system that are seen in the very old ("immunosenescence") and that are likely related in part to persistent inflammation. HIV-associated inflammation and immunosenescence have been implicated as causally related to the premature onset of other end-organ diseases. Novel therapeutic strategies aimed at preventing or reversing these immunologic defects may be necessary if HIV-infected patients are to achieve normal life span.