Electronic Dose Monitoring Device Patterns in Youth Living With HIV Enrolled in an Adherence Intervention Clinical Trial

INTRODUCTION

Youth living with HIV in the US have low rates of viral suppression, in part because of challenges with antiretroviral therapy adherence.

METHODS

Daily dosing in the Adolescent Medicine Trials Network for HIV/AIDS Interventions 152 study, a randomized controlled trial of a 12-week adherence intervention (triggered escalating real-time adherence intervention) for viremic youth, compared with standard of care (SOC), was measured by electronic dose monitoring (EDM) throughout 48 weeks of follow-up. EDM data collected over the first 24 weeks were used to characterize patterns of antiretroviral therapy adherence with group-based trajectory models.

RESULTS

Four trajectory groups were identified among the 85 participants included in the analysis during the intervention phase of the study: (Worst) no interaction with EDM, (Declining) initially moderate EDM-based adherence followed by steep declines, (Good) initially high EDM-based adherence with modest declines, and (Best) consistently high EDM-based adherence. Being in the SOC arm, not being in school, higher evasiveness and panic decision-making scores, and lower adherence motivation were associated with higher odds of being in a worse trajectory group ( P < 0.05). A general decline in dosing was observed in the 12 weeks postintervention, when all participants were managed using SOC.

CONCLUSIONS

Use of group-based trajectory models allowed a more nuanced understanding of EDM-based adherence over time compared with collapsed summary measures. In addition to the study intervention, other factors influencing EDM-based adherence included being in school, decision-making styles, and adherence-related motivation. This information can be used to design better intervention services for youth living with HIV.

Predicting the effect of fresh gas flow on tidal volume in volume-controlled mechanically ventilated dogs

OBJECTIVES

To determine if the tidal volume (V_T) delivered (V_TDEL) to canine patients being mechanically ventilated by a volume-controlled ventilator differed from the volume set on the ventilator (V_TSET) at three fresh gas flow (FGF) rates. To determine if V_TDEL could be accurately predicted by an FGF-based mathematical model.

STUDY DESIGN

Prospective proof-of-concept study.

ANIMALS

A total of 23 adult client-owned dogs undergoing elective orthopedic surgery.

METHODS

Dogs were anesthetized and ventilated with a volume-controlled mechanical ventilator with constant respiratory rate (f_R) of 10 breaths minute^-1, inspiratory-to-expiratory ratio of 1:2 [fraction of inspiratory time (T_I) in one respiratory cycle (T_tot) 1:3], and V_TSET as body weight (kg) × 15 (mL kg^-1). V_TDEL was measured in 20 dogs at three FGF (500, 1000 and 4000 mL minute^-1). A mathematical model was used to calculate predicted volume (V_TPRED) for each animal at each FGF: V_TSET + {FGF × [(T_I/T_tot)/f_R]}. Linear repeated measures models were fit comparing V_TDEL to V_TSET and to V_TPRED by FGF.

RESULTS

V_TDEL was significantly higher than V_TSET at every FGF (p < 0.05), and differences were larger at higher FGF (p < 0.001). There were no statistically significant differences between V_TDEL and V_TPRED at FGF rates of 500 and 4000 mL minute^-1 and, although the mean V_TDEL was statistically significantly higher than V_TPRED at FGF 1000 mL minute^-1 (p = 0.017), the mean difference of 9 mL was not clinically significant.

CONCLUSIONS AND CLINICAL RELEVANCE

Dogs on volume-controlled ventilators may be ventilated at a higher V_TDEL than intended depending on the FGF settings. Ventilation of small animals at high FGF could inadvertently induce pulmonary damage. A mathematical equation can be used to achieve a desired V_TDEL by adjusting V_TSET values based on FGF, f_R and T_I/T_tot.

Randomized Controlled Trial of a Remote Coaching mHealth Adherence Intervention in Youth Living with HIV

Youth living with HIV (YLWH) in the US have low rates of viral suppression (VS). In a prospective randomized clinical trial (ATN152) that enrolled 89 YLWH on antiretroviral therapy (ART) with detectable viral load, we evaluated a 12 week triggered escalating real-time adherence (TERA) intervention with remote coaching, electronic dose monitoring (EDM), and outreach for missed/delayed doses compared to standard of care (SOC). Median [Q1, Q3] percent days with EDM opening was higher in TERA (72% (47%, 89%)) versus SOC (41% (21%, 59%); p < 0.001) and incidence of numbers of 7 day gaps between openings were lower (TERA to SOC ratio: 0.40; 95% CI 0.30, 0.53; p < 0.001). There were no differences in VS at week 12 (TERA 35%; 95% CI 21%, 51% versus SOC 36%; 95% CI 22%, 51%; p > 0.99) or later time-points. The intervention improved adherence but not VS in heavily ART-experienced YLWH. Remote coaching more closely tailored to the unique dosing patterns and duration of need for youth struggling to reach VS warrants further investigation.

Incorporating estimands into clinical trial statistical analysis plans

BACKGROUND

International Council for Harmonisation (ICH) E9 Statistical Principles for Clinical Trials was developed as a consensus guidance document to encourage worldwide harmonization of the principles of statistical methodology in clinical trials. Addendum E9 (R1) clarified and extended ICH E9 with a focus on estimands and sensitivity analyses. Since the release of E9 (R1), clinical trial protocols have included estimands, but there is variation in how they are presented. Statistical analysis plans (SAPs) are increasingly becoming publicly available (e.g. posting on ClinicalTrials.gov) and present an opportunity to link estimands with planned analyses to present the alignment of trial objectives, design, conduct, and analysis.

METHODS

A table format was used to create a template for inclusion in SAPs that satisfies ICH E9 (R1) guidance to align statistical analysis to the estimand. The template provides a consistent structure for presentation of estimands and the associated analysis, and is applicable to a wide range of trial designs. We illustrate use of the template with a hypothetical clinical trial in HIV-1.

RESULTS

The estimand-to-analysis table template starts with the study objective describing the clinical question of interest as written in the trial protocol. The remainder of the table describes each attribute of the estimand (treatment, target population, variable, intercurrent events, and population-level summary) in the left column (ESTIMAND), while the right column describes how each attribute will be handled using the data collected in the clinical trial (ANALYSIS). The template was applied to a hypothetical, early-phase single-arm trial, modeled after a pediatric trial in HIV, where the objective was to determine the safety of a new antiretroviral drug as part of a combination antiretroviral treatment regimen in the pediatric population. Three intercurrent events were illustrated in the table: death, premature treatment discontinuation before 24 weeks, and pregnancy. An estimand-to-analysis table from a grant application that addresses the primary objective of a placebo-controlled randomized trial is also presented to demonstrate an alternative usage.

CONCLUSION

We found the template to be useful in study design, providing a snapshot of the objective, target population, potential intercurrent events, analysis plan, and considerations for missing data in one place and facilitating discussion among stakeholders. The proposed standardized presentation of estimand attributes and analysis considerations in SAPs will provide guidance to SAP authors and consistency across studies to facilitate reviews.

Plasma biomarker factors associated with neurodevelopmental outcomes in children with perinatal HIV infection and controlled viremia

OBJECTIVE

We examined relationships between plasma biomarkers and neurodevelopment in children from sub-Saharan Africa with perinatal HIV (PHIV) with controlled viremia on antiretroviral therapy (ART).

DESIGN

Longitudinal retrospective cohort study of children with controlled blood HIV replication.

METHODS

Children (N = 213; 57% girls) started ART at less than 3 years of age, had neurodevelopmental assessments (cognition, attention/impulsivity, motor proficiency, global executive functions) at 5-11 years, and achieved controlled viremia (HIV-1 RNA <400 copies/ml for ≥9 months before initial assessment). Twenty-three plasma biomarkers were measured at onset of controlled viremia, week 0 (first neurodevelopmental assessment), and week 48 (second neurodevelopmental assessment). Factor analysis was conducted at each time point. Multivariable linear regressions assessed associations between factors and neurodevelopmental scores.

RESULTS

Median age at week 0 was 7.0 years. Eighteen biomarkers loaded on six factors: a (L-10, IFNγ, IFNα2, IL-1β, IL-6, IP-10, TNFα); B (sCD163, sICAM-1, sVCAM-1, CRP); C (sE-selectin, sP-selectin); D [MIP-1β, vascular endothelial growth factor (VEGF)-A]; E (sCD14, CRP); and F (CX3CL1, MCP-1). Higher factor B scores were consistently associated with worse cognition and attention/impulsivity, and higher factor D scores with better attention/impulsivity.

CONCLUSION

These results suggest a detrimental effect of increased endothelial cell activation (sICAM-1, sVCAM-1) and monocyte/macrophage scavenger function (sCD163) and a beneficial effect of increased CCR5 ligand and HIV entry blocker MIP-1β and angiogenesis stimulant-VEGF concentrations on the neurodevelopment of children with PHIV. The model that emerges is of vascular inflammation leading to neurodevelopmental deficits. The role of persistent HIV replication in the central nervous system also needs to be further explored.

Correlates of High HIV Viral Load and Antiretroviral Therapy Adherence Among Viremic Youth in the United States Enrolled in an Adherence Improvement Intervention

A sizable portion of youth (ages 13-24) living with HIV in the United States have unsuppressed viral load. The AIDS Interventions (ATN) 152 study [evaluating the Triggered Escalating Real-Time Adherence (TERA) intervention] baseline data were examined to identify correlates of high viremia (>5000 copies/mL) and self-reported adherence, which can help in planning of differentiated services for viremic youth. Depression, HIV-stigma, and cannabis use were common in this sample of 87 youth. Almost half (48%) had high viremia, which associated with enacted stigma, moderate- to high-risk alcohol use, mental health diagnosis, and age ≥21. Self-reported adherence was related to viral load and associated with mental and physical health functioning, depression, social support, self-confident decision-making, total and internalized stigma, adherence motivation, and report of a missed a care visit in the past 6 months. Mental health emerged as a common correlate of viral load and adherence. Clinical Trial Registration number: NCT03292432.

Safety and Efficacy of 48 and 96 Weeks of Alendronate in Children and Adolescents With Perinatal Human Immunodeficiency Virus Infection and Low Bone Mineral Density for Age

No safety concerns were identified in a randomized, crossover study of alendronate/placebo in youth with perinatal HIV infection and low bone mineral density (BMD). BMD improved with 48 weeks of alendronate and continued to improve with an additional 48 weeks of therapy. Gains were largely maintained 48 weeks after stopping alendronate.

Alendronate Improves Bone Mineral Density in Children and Adolescents Perinatally Infected With Human Immunodeficiency Virus With Low Bone Mineral Density for Age

BACKGROUND

Children and adolescents with perinatal human immunodeficiency virus (HIV) infection and with low bone mineral density (BMD) may be at higher risk of osteoporosis and fractures in later life than their uninfected peers. Bisphosphonate therapy has been shown to reduce fractures in adults with osteoporosis, but has not been formally studied in youths living with HIV.

METHODS

Fifty-two children and adolescents (aged 11-24 years) perinatally infected with HIV with low lumbar spine (LS) BMD (Z score < -1.5) were randomized to receive once-weekly alendronate or placebo in a double-blind cross-over study designed to assess the safety and efficacy of 48 and 96 weeks of alendronate in the United States and Brazil. All participants received daily calcium carbonate and vitamin D supplementation and were asked to engage in regular weight-bearing exercise. Safety and efficacy are summarized for the initial 48 weeks of the trial.

RESULTS

Grade 3 or higher abnormal laboratory values, signs, or symptoms developed in 5 of 32 (16%) participants on alendronate and 2 of 18 (11%) on placebo (P > .99). No cases of jaw osteonecrosis, atrial fibrillation, or nonhealing fractures were reported. Mean increases (95% confidence interval) in LS BMD over 48 weeks were significantly larger on alendronate (20% [14%-25%]) than placebo (7% [5%-9%]) (P < .001). Similar improvements were seen for whole body BMD.

CONCLUSIONS

In this small study in children and adolescents perinatally infected with HIV with low LS BMD, 48 weeks of alendronate was well-tolerated, showed no safety concerns, and significantly improved LS and whole body BMD compared to participants on vitamin D/calcium supplementation and exercise alone.

CLINICAL TRIALS REGISTRATION

NCT00921557.

Sedative effects of alfaxalone and hydromorphone with or without midazolam in cats: a pilot study

OBJECTIVES

The aim of this pilot study was to compare the quality of sedation and ease of intravenous (IV) catheter placement following sedation using two intramuscular (IM) sedation protocols in cats: hydromorphone, alfaxalone and midazolam vs hydromorphone and alfaxalone.

METHODS

This was a prospective, randomized and blinded study. Cats were randomly assigned to receive an IM injection of hydromorphone (0.1 mg/kg), alfaxalone (1.5 mg/kg) and midazolam (0.2 mg/kg; HAM group), or hydromorphone (0.1 mg/kg) and alfaxalone (1.5 mg/kg; HA group). Sedation scoring (0-9, where 9 indicated maximum sedation) was performed at 0, 5, 10, 15 and 20 mins from the time of injection. At 20 mins, an IV catheter placement score (0-10, where 10 indicated least resistance) was performed.

RESULTS

Twenty-one client-owned adult cats were included in this study. Sedation and IV catheter placement scores were compared between groups using Wilcoxon rank sum tests. Peak sedation was significantly higher (P = 0.002) in the HAM group (median 9; range 7-9) than in the HA group (median 7; range 3-9), and IV catheter placement scores were significantly higher (P = 0.001) in the HAM group (median 9.5; range 7-10) compared with the HA group (median 7; range 4-9). Spearman correlations were calculated between IV catheter placement score and sedation scores. There was a significant positive correlation of average sedation over time (correlation 0.83; P <0.001) and sedation at 20 mins (correlation 0.76; P <0.001) with a higher, more favorable IV catheter placement score.

CONCLUSIONS AND RELEVANCE

These preliminary results suggest that the addition of midazolam to IM alfaxalone and hydromorphone produced more profound sedation and greater ease of IV catheter placement than IM alfaxalone and hydromorphone alone.

Immune Markers and Their Association with Bone Density in Children, Adolescents, and Young Adults with Perinatally Acquired HIV

To describe distributions of immune markers in children and young adults by sex and HIV status, and within groups, investigate associations of immune markers with bone density across Tanner stage. Using data and samples from 353 participants in a cross-sectional study in youth with perinatally acquired HIV (PHIV) and matched HIV-negative controls, distributions of inflammation and activation immune markers were described by sex and HIV status. Correlations and structural equation models (SEM) were used to explore marginal and multivariable associations of the immune markers with bone density and to assess whether patterns of association varied by sex and HIV status. Immune marker distributions did not differ by sex, but there were some differences by HIV status. Correlation patterns among bone, body composition, and immune markers were similar across the sex and HIV status groups. Conclusions from SEMs were limited by small sample sizes, but there was some indication that patterns of association between bone density and certain immune markers differed in male PHIV with more advanced Tanner stage compared to the other three groups. In conclusion, distributions of bone density, body composition, and immune markers may vary by sex and HIV status, although associations among these outcomes within sex and HIV status groups appear similar. Bone density of male PHIV appears to be more negatively affected than females, regardless of female HIV status. Larger longitudinal studies across Tanner stages are needed to further explore potential biological relationships between immune markers and bone density in youth living with HIV.

The molecular landscape and associated clinical experience in infant medulloblastoma: prognostic significance of second-generation subtypes

AIMS

Biomarker-driven therapies have not been developed for infant medulloblastoma (iMB). We sought to robustly sub-classify iMB, and proffer strategies for personalized, risk-adapted therapies.

METHODS

We characterized the iMB molecular landscape, including second-generation subtyping, and the associated retrospective clinical experience, using large independent discovery/validation cohorts (n = 387).

RESULTS

iMB_Grp3 (42%) and iMB_SHH (40%) subgroups predominated. iMB_Grp3 harboured second-generation subtypes II/III/IV. Subtype II strongly associated with large-cell/anaplastic pathology (LCA; 23%) and MYC amplification (19%), defining a very-high-risk group (0% 10yr overall survival (OS)), which progressed rapidly on all therapies; novel approaches are urgently required. Subtype VII (predominant within iMB_Grp4 ) and subtype IV tumours were standard risk (80% OS) using upfront CSI-based therapies; randomized-controlled trials of upfront radiation-sparing and/or second-line radiotherapy should be considered. Seventy-five per cent of iMB_SHH showed DN/MBEN histopathology in discovery and validation cohorts (P < 0.0001); central pathology review determined diagnosis of histological variants to WHO standards. In multivariable models, non-DN/MBEN pathology was associated significantly with worse outcomes within iMB_SHH . iMB_SHH harboured two distinct subtypes (iMB_SHH-I/II ). Within the discriminated favourable-risk iMB_SHH DN/MBEN patient group, iMB_SHH-II had significantly better progression-free survival than iMB_SHH-I , offering opportunities for risk-adapted stratification of upfront therapies. Both iMB_SHH-I and iMB_SHH-II showed notable rescue rates (56% combined post-relapse survival), further supporting delay of irradiation. Survival models and risk factors described were reproducible in independent cohorts, strongly supporting their further investigation and development.

CONCLUSIONS

Investigations of large, retrospective cohorts have enabled the comprehensive and robust characterization of molecular heterogeneity within iMB. Novel subtypes are clinically significant and subgroup-dependent survival models highlight opportunities for biomarker-directed therapies.

Postoperative regurgitation and respiratory complications in brachycephalic dogs undergoing airway surgery before and after implementation of a standardized perianesthetic protocol

OBJECTIVE

To determine whether implementation of a standardized perianesthetic protocol was associated with reduced incidence of postoperative regurgitation, pneumonia, and respiratory distress in brachycephalic dogs undergoing general anesthesia for airway surgery.

ANIMALS

84 client-owned dogs.

PROCEDURES

A perianesthetic protocol that included preoperative administration of metoclopramide and famotidine, restrictive use of opioids, and recovery of patients in the intensive care unit was fully implemented for brachycephalic dogs in July 2014. Medical records of brachycephalic dogs (specifically Boston Terriers, French Bulldogs, English Bulldogs, and Pugs) undergoing anesthesia for airway surgery before (group A) and after (group B) protocol implementation were reviewed. Patient characteristics, administration of medications described in the protocol, surgical procedures performed, anesthesia duration, recovery location, and postoperative development of regurgitation, pneumonia, and respiratory distress were recorded. Data were compared between groups.

RESULTS

The proportion of dogs with postoperative regurgitation in group B (4/44 [9%]) was significantly lower than that in group A (14/40 [35%]). No intergroup differences in patient characteristics (including history of regurgitation), procedures performed, or anesthesia duration were found. Rates of development of postoperative pneumonia and respiratory distress did not differ between groups. A history of regurgitation was associated with development of postoperative regurgitation.

CONCLUSIONS AND CLINICAL RELEVANCE

Implementation of the described protocol was associated with decreased incidence of postoperative regurgitation in brachycephalic dogs undergoing anesthesia. Prospective studies are warranted to elucidate specific causes of this finding.

Intestinal Integrity Biomarkers in Early Antiretroviral-Treated Perinatally HIV-1-Infected Infants

Intestinal fatty acid binding protein (iFABP) levels did not differ between human immunodeficiency virus type 1 (HIV-1)- infected infants and uninfected infants exposed to HIV-1, but those who breastfed had substantially lower levels. Zonulin levels increased from 3 to 5.3 months of age with perinatal acquisition of HIV-1 despite early antiretroviral treatment. Biomarkers of intestinal integrity (ie, iFABP and zonulin) were compared in 56 HIV-1-positive African infants who received early antiretroviral treatment and 53 HIV-1-exposed but uninfected (HEU) controls. Despite heightened inflammation and immune activation in HIV-positive infants, iFABP and zonulin levels at 3 months of age were not different from those in HEU infants and largely were not correlated with inflammatory and immune activation biomarkers. However, zonulin levels increased and became significantly higher in HIV-positive infants as compared to HEU infants by 5 months of age, despite viral suppression due to antiretroviral treatment. These findings have implications for intestinal integrity biomarker profiling in perinatal HIV-1 infection.

Concomitant nevirapine impacts pharmacokinetic exposure to the antimalarial artemether-lumefantrine in African children

BACKGROUND

The antiretroviral drug nevirapine and the antimalarial artemisinin-based combination therapy artemether-lumefantrine are commonly co-administered to treat malaria in the context of HIV. Nevirapine is a known inhibitor of cytochrome P450 3A4, which metabolizes artemether and lumefantrine. To address the concern that the antiretroviral nevirapine impacts the antimalarial artemether-lumefantrine pharmacokinetics, a prospective non-randomized controlled study in children presenting with uncomplicated malaria and HIV in sub-Saharan Africa was carried out.

METHODS

Participants received artemether-lumefantrine (20/120 mg weight-based BID) for 3 days during nevirapine-based antiretroviral therapy (ART) co-administration (158-266 mg/m2 QD). HIV positive participants who were not yet on ART drugs were also enrolled as the control group. The target enrollment was children aged 3-12 years (n = 24 in each group). Intensive pharmacokinetics after the last artemether-lumefantrine dose was assessed for artemether, its active metabolite dihydroartemisinin, and lumefantrine. Pharmacokinetic parameters (area under the plasma concentration vs. time curve (AUC), maximum concentration and day 7 lumefantrine concentrations) were estimated using non-compartmental methods and compared to controls.

RESULTS

Nineteen children (16 on nevirapine and three not on ART) enrolled. Fifteen of the 16 (aged 4 to 11 years) on nevirapine-based ART were included in the pharmacokinetic analysis. Due to evolving WHO HIV treatment guidelines, insufficient children were enrolled in the control group (n = 3), so the pharmacokinetic data were compared to a historical control group of 20 HIV-uninfected children 5-12 years of age who also presented with malaria and underwent identical study procedures. Decreases of pharmacokinetic exposure [as estimated by AUC (AUC0-8hr)] were marginally significant for artemether (by -46%, p = 0.08) and dihydroartemisinin (-22%, p = 0.06) in the children on nevirapine-based ART, compared to when artemether-lumefantrine was administered alone. Similarly, peak concentration was decreased by 50% (p = 0.07) for artemether and 36% (p = 0.01) for dihydroartemisinin. In contrast, exposure to lumefantrine increased significantly in the context of nevirapine [AUC0-120hr:123% (p<0.001); Cday7:116% (p<0.001), Cmax: 95% (p<0.001)].

CONCLUSIONS

Nevirapine-based ART increases the exposure to lumefantrine in pre-pubescent children with a trend toward diminished artemether and dihydroartemisinin exposure. These findings contrast with other studies indicating NVP reduces or results in no change in exposure of antimalarial drugs, and may be specific to this age group (4-12 years). Considering the excellent safety profile of artemether-lumefantrine, the increase in lumefantrine is not of concern. However, the reduction in artemisinin exposure may warrant further study, and suggests that dosage adjustment of artemether-lumefantrine with nevirapine-based ART in children is likely warranted.

Minimal methylation classifier (MIMIC): A novel method for derivation and rapid diagnostic detection of disease-associated DNA methylation signatures

Rapid and reliable detection of disease-associated DNA methylation patterns has major potential to advance molecular diagnostics and underpin research investigations. We describe the development and validation of minimal methylation classifier (MIMIC), combining CpG signature design from genome-wide datasets, multiplex-PCR and detection by single-base extension and MALDI-TOF mass spectrometry, in a novel method to assess multi-locus DNA methylation profiles within routine clinically-applicable assays. We illustrate the application of MIMIC to successfully identify the methylation-dependent diagnostic molecular subgroups of medulloblastoma (the most common malignant childhood brain tumour), using scant/low-quality samples remaining from the most recently completed pan-European medulloblastoma clinical trial, refractory to analysis by conventional genome-wide DNA methylation analysis. Using this approach, we identify critical DNA methylation patterns from previously inaccessible cohorts, and reveal novel survival differences between the medulloblastoma disease subgroups with significant potential for clinical exploitation.

Inflammation and Immune Activation in Antiretroviral-Treated Human Immunodeficiency Virus Type 1-Infected African Infants and Rotavirus Vaccine Responses

Biomarkers of inflammation and immune activation were correlated with rotavirus vaccine responses in 68 human immunodeficiency virus type 1 (HIV-1)–infected (and 116 HIV-exposed but uninfected (HEU) African infants receiving pentavalent rotavirus vaccine (RV5) in a clinical trial. Prevaccination, HIV-1+ infants had significantly higher concentrations of interferon γ (IFNγ), interleukin1β, interleukin 2, interleukin 6, interleukin 10 (IL-10), and soluble CD14 compared with HEU infants. Postvaccination concentrations of neutralizing antibodies to RV5 were negatively correlated with prevaccination concentrations of IL-10 (RV5 surface proteins G1 and P1) and IFNγ (G1) in the HIV-1+ infants, whereas antirotavirus immunoglobulin A (IgA) levels were not. Heightened inflammation and immune activation in HIV-1+ infants did not alter IgA responses associated with protection from rotavirus disease.

Evaluation of risk factors, including fluconazole administration, for prolonged anesthetic recovery times in horses undergoing general anesthesia for ocular surgery: 81 cases (2006-2013)

OBJECTIVE--To determine risk factors for prolonged anesthetic recovery time in horses that underwent general anesthesia for ocular surgery. DESIGN--Retrospective cohort study. ANIMALS--81 horses that underwent general anesthesia for ocular surgery between 2006 and 2013. PROCEDURES--Descriptive information recorded included the ocular procedure performed, concurrent fluconazole treatments, analgesic and anesthetic agents administered, procedure duration, use of sedation for recovery, and recovery time. Data were analyzed for associations between recovery time and other variables. RESULTS--81 horses met inclusion criteria. In 72 horses, anesthesia was induced with ketamine and midazolam; 16 horses treated concurrently with fluconazole had significantly longer mean recovery time (109 minutes [95% confidence interval {CI}, 94 to 124 minutes]) than did 56 horses that were not treated with fluconazole (50 minutes [95% CI, 44 to 55 minutes]). In 9 horses anesthetized with a protocol that included ketamine but did not include midazolam, there was no difference between mean recovery time in horses that either received (59 minutes [95% CI, 36 to 81 minutes]; n = 5) or did not receive (42 minutes [95% CI, 16 to 68 minutes]; 4) fluconazole. Other variables identified as risk factors for prolonged recovery included duration of anesthesia and use of acepromazine for premedication. CONCLUSIONS AND CLINICAL RELEVANCE--Fluconazole administration was associated with prolonged anesthetic recovery time in horses when ketamine and midazolam were used to induce anesthesia for ocular surgery. Duration of anesthesia and premedication with acepromazine were also identified as risk factors for prolonged recovery time.

Association of pol diversity with antiretroviral treatment outcomes among HIV-infected African children

Background

In HIV-infected children, viral diversity tends to increase with age in the absence of antiretroviral treatment (ART). We measured HIV diversity in African children (ages 6–36 months) enrolled in a randomized clinical trial comparing two ART regimens (Cohort I of the P1060 trial). Children in this cohort were exposed to single dose nevirapine (sdNVP) at birth.

Methods

HIV diversity was measured retrospectively using a high resolution melting (HRM) diversity assay. Samples were obtained from 139 children at the enrollment visit prior to ART initiation. Six regions of the HIV genome were analyzed: two in gag, one in pol, and three in env. A single numeric HRM score that reflects HIV diversity was generated for each region; composite HRM scores were also calculated (mean and median for all six regions).

Results

In multivariable median regression models using backwards selection that started with demographic and clinical variables, older age was associated with higher HRM scores (higher HIV diversity) in pol (P = 0.005) and with higher mean (P = 0.014) and median (P<0.001) HRM scores. In multivariable models adjusted for age, pre-treatment HIV viral load, pre-treatment CD4%, and randomized treatment regimen, higher HRM scores in pol were associated with shorter time to virologic suppression (P = 0.016) and longer time to study endpoints (virologic failure [VF], VF/death, and VF/off study treatment; P<0.001 for all measures).

Conclusions

In this cohort of sdNVP-exposed, ART-naïve African children, higher levels of HIV diversity in the HIV pol region prior to ART initiation were associated with better treatment outcomes.

Ethical tradeoffs in trial design: case study of an HPV vaccine trial in HIV-infected adolescent girls in lower income settings

The Declaration of Helsinki and the Council of the International Organization of Medical Sciences provide guidance on standards of care and prevention in clinical trials. In the current and increasingly challenging research environment, the ethical status of a trial design depends not only on protection of participants, but also on social value, feasibility, and scientific validity. Using the example of a study assessing efficacy of a vaccine to prevent human papilloma virus in HIV-1 infected adolescent girls in low resource countries without access to the vaccine, we compare several trial designs which rank lower on some criteria and higher on others, giving rise to difficult trade-offs. This case demonstrates the need for developing more nuanced guidance documents to help researchers balance these often conflicting criteria.

Nevirapine versus ritonavir-boosted lopinavir for HIV-infected children

BACKGROUND

Nevirapine-based antiretroviral therapy is the predominant (and often the only) regimen available for children in resource-limited settings. Nevirapine resistance after exposure to the drug for prevention of maternal-to-child human immunodeficiency virus (HIV) transmission is common, a problem that has led to the recommendation of ritonavir-boosted lopinavir in such settings. Regardless of whether there has been prior exposure to nevirapine, the performance of nevirapine versus ritonavir-boosted lopinavir in young children has not been rigorously established.

METHODS

In a randomized trial conducted in six African countries and India, we compared the initiation of HIV treatment with zidovudine, lamivudine, and either nevirapine or ritonavir-boosted lopinavir in HIV-infected children 2 to 36 months of age who had no prior exposure to nevirapine. The primary end point was virologic failure or discontinuation of treatment by study week 24.

RESULTS

A total of 288 children were enrolled; the median percentage of CD4+ T cells was 15%, and the median plasma HIV type 1 (HIV-1) RNA level was 5.7 log(10) copies per milliliter. The percentage of children who reached the primary end point was significantly higher in the nevirapine group than in the ritonavir-boosted lopinavir group (40.8% vs. 19.3%; P<0.001). Among the nevirapine-treated children with virologic failure for whom data on resistance were available, more than half (19 of 32) had resistance at the time of virologic failure. In addition, the time to a protocol-defined toxicity end point was shorter in the nevirapine group (P=0.04), as was the time to death (P=0.06).

CONCLUSIONS

Outcomes were superior with ritonavir-boosted lopinavir among young children with no prior exposure to nevirapine. Factors that may have contributed to the suboptimal results with nevirapine include elevated viral load at baseline, selection for nevirapine resistance, background regimen of nucleoside reverse-transcriptase inhibitors, and the standard ramp-up dosing strategy. The results of this trial present policymakers with difficult choices. (Funded by the National Institute of Allergy and Infectious Diseases and others; P1060 ClinicalTrials.gov number, NCT00307151.).

Using cluster heat maps to investigate relationships between body composition and laboratory measurements in HIV-infected and HIV-uninfected children and young adults

Cluster heat maps were used to investigate relationships between body composition, lipid levels, and glucose metabolism in HIV-infected and HIV-uninfected children and young adults using data from a cross-sectional study. Three distinct clusters of participants were identified. One group had lower body fat and higher lipid measures and was mostly HIV infected. The other 2 groups were a mix of HIV-infected and HIV-uninfected participants. Of these, 1 cluster had more participants with higher body fat and insulin resistance, which are risk factors for future cardiovascular disease, and the other had relatively normal measurements on all outcomes.

Antiretroviral treatment for children with peripartum nevirapine exposure

BACKGROUND

Single-dose nevirapine is the cornerstone of the regimen for prevention of mother-to-child transmission of human immunodeficiency virus (HIV) in resource-limited settings, but nevirapine frequently selects for resistant virus in mothers and children who become infected despite prophylaxis. The optimal antiretroviral treatment strategy for children who have had prior exposure to single-dose nevirapine is unknown.

METHODS

We conducted a randomized trial of initial therapy with zidovudine and lamivudine plus either nevirapine or ritonavir-boosted lopinavir in HIV-infected children 6 to 36 months of age, in six African countries, who qualified for treatment according to World Health Organization (WHO) criteria. Results are reported for the cohort that included children exposed to single-dose nevirapine prophylaxis. The primary end point was virologic failure or discontinuation of treatment by study week 24. Enrollment in this cohort was terminated early on the recommendation of the data and safety monitoring board.

RESULTS

A total of 164 children were enrolled. The median percentage of CD4+ lymphocytes was 19%; a total of 56% of the children had WHO stage 3 or 4 disease. More children in the nevirapine group than in the ritonavir-boosted lopinavir group reached a primary end point (39.6% vs. 21.7%; weighted difference, 18.6 percentage-points; 95% confidence interval, 3.7 to 33.6; nominal P=0.02). Baseline resistance to nevirapine was detected in 18 of 148 children (12%) and was predictive of treatment failure. No significant between-group differences were seen in the rate of adverse events.

CONCLUSIONS

Among children with prior exposure to single-dose nevirapine for perinatal prevention of HIV transmission, antiretroviral treatment consisting of zidovudine and lamivudine plus ritonavir-boosted lopinavir resulted in better outcomes than did treatment with zidovudine and lamivudine plus nevirapine. Since nevirapine is used for both treatment and perinatal prevention of HIV infection in resource-limited settings, alternative strategies for the prevention of HIV transmission from mother to child, as well as for the treatment of HIV infection, are urgently required. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT00307151.).

Implications of Discrimination Based on Sexuality, Gender, and Race/Ethnicity for Psychological Distress among Working-Class Sexual Minorities: The United for Health Study, 2003–2004

This study investigated the distribution of demographic characteristics, the prevalence of discrimination based on sexuality, gender, and race, and relationships with psychological distress among 178 working-class sexual minorities (i.e., who identified as lesbian, gay, or bisexual (LGB) or had ever engaged in same-sex sexual behaviors) recruited to the United for Health Study (2003–2004). The results indicated considerable heterogeneity in responses to items assessing sexual orientation and sexual behavior, with a majority of sexual minority participants not identifying as LGB (74.2%). The authors found significant demographic differences in LGB identification by gender, race/ethnicity, nativity, and socioeconomic factors. In addition, LGB participants had higher levels of psychological distress than non-LGB-identified sexual minorities. Linear regression analyses revealed that reports of racial/ethnic discrimination and sexuality discrimination were associated with higher levels of psychological distress among sexual minority participants. The results underscore the need to collect multiple measures of sexuality in conducting research on racially diverse working-class communities; to consider demographic factors in collecting sexuality data; and to disaggregate information on sexuality by LGB identification. Findings also highlight the importance of addressing discrimination in ameliorating problematic mental health outcomes among working-class sexual minorities.

Alcohol disorders among Asian Americans: associations with unfair treatment, racial/ethnic discrimination, and ethnic identification (the national Latino and Asian Americans study, 2002-2003)

STUDY OBJECTIVE

To examine history of alcohol abuse/dependence disorder in relation to unfair treatment, racial/ethnic discrimination, and ethnic identification among Asian Americans.

DESIGN

Weighted multivariate analyses of cross-sectional national survey data predicting lifetime history of alcohol abuse/dependence disorders.

SETTING

USA, Asian Americans.

PARTICIPANTS

2007 Asian American adults recruited to the National Latino and Asian American Study (NLAAS; 2002-2003).

RESULTS

Controlling for sociodemographic characteristics, Asian Americans who reported experiencing unfair treatment had higher odds of history of alcohol abuse/dependence disorder (OR 5.26, 95% CI 1.90 to 14.56). Participants who reported high levels of ethnic identification had lower odds of history of alcohol abuse/dependence disorders (OR 0.46, 95% CI 0.23 to 0.90). Ethnic identification moderated the influence of racial/ethnic discrimination (p = 0.097). Among participants with low levels of ethnic identification, racial/ethnic discrimination was associated with greater odds of having a history of alcohol disorder compared with those with high levels of ethnic identification.

CONCLUSIONS

Social hazards such as unfair treatment and racial/ethnic discrimination should be considered in the development of programmes addressing alcohol disorders among Asian Americans. Interventions that promote ethnic identification in this population may be particularly relevant in mitigating the negative influence of racial/ethnic discrimination on alcohol disorders.

Adherence to antiretrovirals among US women during and after pregnancy

BACKGROUND

Antiretrovirals (ARVs) are recommended for maternal health and to reduce HIV-1 mother-to-child transmission, but suboptimal adherence can counteract its benefits.

OBJECTIVES

To describe antepartum and postpartum adherence to ARV regimens and factors associated with adherence.

METHODS

We assessed adherence rates among subjects enrolled in Pediatric AIDS Clinical Trials Group Protocol 1,025 from August 2002 to July 2005 on tablet formulations with at least one self-report adherence assessment. Perfectly adherent subjects reported no missed doses 4 days before their study visit. Generalized estimating equations were used to compare antepartum with postpartum adherence rates and to identify factors associated with perfect adherence.

RESULTS

Of 519 eligible subjects, 334/445 (75%) reported perfect adherence during pregnancy. This rate significantly decreased 6, 24, and 48 weeks postpartum [185/284 (65%), 76/118 (64%), and 42/64 (66%), respectively (P < 0.01)]. Pregnant subjects with perfect adherence had lower viral loads. The odds of perfect adherence were significantly higher for women who initiated ARVs during pregnancy (P < 0.01), did not have AIDS (P = 0.02), never missed prenatal vitamins (P < 0.01), never used marijuana (P = 0.05), or felt happy all or most of the time (P < 0.01).

CONCLUSIONS

Perfect adherence to ARVs was better antepartum, but overall rates were low. Interventions to improve adherence during pregnancy are needed.

Analyses of HIV-1 drug-resistance profiles among infected adolescents experiencing delayed antiretroviral treatment switch after initial nonsuppressive highly active antiretroviral therapy

Treatment failure and drug resistance create obstacles to long-term management of HIV-1 infection. Nearly 60% of infected persons fail their first highly active antiretroviral therapy (HAART) regimen, partially because of nonadherence, requiring a switch to a second regimen to prevent drug resistance. Among HIV-infected youth, a group with rising infection rates, treatment switch is often delayed; virologic and immunologic consequences of this delay are unknown. We conducted a retrospective, longitudinal study of drug resistance outcomes of initial HAART in U.S. youth enrolled between 1999-2001 in a multicenter, observational study and experiencing delayed switch in their first nonsuppressive treatment regimen for up to 3 years. HIV-1 genotyping was performed on plasma samples collected longitudinally, and changes in drug resistance mutations, CD4+ T cell numbers and viral replication capacity were assessed. Forty-four percent (n = 18) of youth in the parent study experiencing virologic nonsuppression were maintained on their initial HAART regimen for a median of 144 weeks. Drug resistance was detected in 61% (11/18) of subjects during the study. Subjects on non-nucleoside reverse transcriptase inhibitor (NNRTI) regimens developed more (8/10) drug resistance mutations than those on protease-inhibitor (PI) regimens (2/7) (p = 0.058). Subjects developing NNRTI-resistance (NNRTI-R), showed a trend toward lower CD4+ T cell gains (median: -6 cells/mm(3) per year) than those without detectable NNRTI-R (median: +149 cells/mm(3) per year) (p = 0.16). HIV-1-infected youth maintained on initial nonsuppressive NNRTI-based HAART regimens are more likely to develop drug-resistant viremia than with PI-based HAART. This finding may have implications for initial treatment regimens and transmission risk in HIV-infected youth, a group with rising infection rates.

Long-term observation of adolescents initiating HAART therapy: three-year follow-up

The PACTG 381 cohort included 120 adolescents infected via high-risk behaviors and treated with at least two NRTIs plus either a protease inhibitor or an efavirenz-containing HAART regimen. After 24 weeks of therapy, only 69 of 118 (59%) evaluable subjects had undetectable viral loads. We now present findings of the study after 3 years of follow-up. Virologic, immunologic, and treatment information were collected from subjects every 12 weeks beyond the first 24 weeks of therapy through 156 weeks. Of the 120 subjects starting HAART, 44 (37%) stayed on study treatment for the 3 years of observation. Twenty-nine (24%) subjects reached and maintained undetectable viral loads. Poorer adherence (p = 0.016), higher baseline viral load (p = 0.010), and CD8 naive counts (p = 0.034) predicted virologic failure. Immunologic measurements improved from entry to the end of follow-up in the subjects with undetectable viral loads. CD4 counts at the end of study were not significantly different from HIV-uninfected youth, but CD4%, CD8 counts and percent, and CD8 activation markers remained significantly different. Adolescents infected with HIV via high-risk behaviors have less than optimal responses to HAART therapy with only 24% achieving and maintaining undetectable viral loads over 3 years. Immunologic improvement was demonstrated and CD4 counts in subjects with virologic control reached levels in HIV-uninfected adolescents. Interventions, especially those focused on adherence, are necessary to improve HAART outcomes in adolescents.

Intracellular pharmacokinetics of once versus twice daily zidovudine and lamivudine in adolescents

Zidovudine (ZDV) and lamivudine (3TC) metabolism to triphosphates (TP) is necessary for antiviral activity. The aims of this study were to compare ZDV-TP and 3TC-TP concentrations in adolescents receiving twice daily (BID) and once daily (QD) regimens and to determine the metabolite concentrations of ZDV and 3TC during chronic therapy on a QD regimen. Human immunodeficiency virus-infected patients (12 to 24 years) taking ZDV (600 mg/day) and 3TC (300 mg/day) as part of a highly active antiretroviral therapy regimen received QD and BID regimens of ZDV and 3TC for 7 to 14 days in a crossover design. Serial blood samples were obtained over 24 h on the QD regimen. Intracellular mono-, di-, and triphosphates for ZDV and 3TC were measured. The median ratio of BID/QD for ZDV-TP predose concentrations was 1.28 (95% confidence interval [CI] = 1.00 to 2.45) and for 3TC-TP was 1.12 (95% CI = 0.81 to 1.96). The typical population estimated half-lives (+/- the standard error of the mean) were 9.1 +/- 0.859 h for ZDV-TP and 17.7 +/- 2.8 h for 3TC-TP. Most patients had detectable levels of the TP of ZDV (24 of 27) and 3TC (24 of 25) 24 h after dosing, and half-lives on a QD regimen were similar to previously reported values when the drugs were given BID. Lower, but not significantly different, concentrations of ZDV-TP were demonstrated in the QD regimen compared to the BID regimen (P = 0.056). Although findings were similar between the BID and QD groups, the lower concentrations of ZDV and the number of patients below the level of detection after 24 h suggests that ZDV should continue to be administered BID.

Epigenetic deregulation of multiple S100 gene family members by differential hypomethylation and hypermethylation events in medulloblastoma

Deregulated expression of genes encoding members of the S100 family of calcium-binding proteins has been associated with the malignant progression of multiple tumour types. Using a pharmacological expression reactivation approach, we screened 16 S100 genes for evidence of epigenetic regulation in medulloblastoma, the most common malignant brain tumour of childhood. Four family members (S100A2, S100A4, S100A6 and S100A10) demonstrated evidence of upregulated expression in multiple medulloblastoma cell lines, following treatment with the DNA methyltransferase inhibitor, 5′-aza-2′-deoxycytidine. Subsequent analysis revealed methylation of critical CpG sites located within these four genes in an extended cell line panel. Assessment of these genes in the non-neoplastic cerebellum (from which medulloblastomas develop) revealed strong somatic methylation affecting S100A2 and S100A4, whereas S100A6 and S100A10 were unmethylated. Assessed against these normal tissue-specific methylation states, S100A6 and S100A10 demonstrated tumour-specific hypermethylation in medulloblastoma primary tumours (5 out of 40 and 4 out of 35, respectively, both 12%) and cell lines (both 7 out of 9, 78%), which was associated with their transcriptional silencing. Moreover, S100A6 hypermethylation was significantly associated with the aggressive large cell/anaplastic morphophenotype (P=0.026). In contrast, pro-metastatic S100A4 displayed evidence of hypomethylation relative to the normal cerebellum in a significant proportion primary tumours (7 out of 41, 17%) and cell lines (3 out of 9, 33%), which was associated with its elevated expression. In summary, these data characterise complex patterns of somatic methylation affecting S100 genes in the normal cerebellum and demonstrate their disruption causing epigenetic deregulation of multiple S100 family members in medulloblastoma development. Epigenetic events affecting S100 genes have potential clinical utility and merit further investigation as molecular biomarkers for this disease.

Neurodevelopmental functioning in HIV-infected infants and young children before and after the introduction of protease inhibitor-based highly active antiretroviral therapy

OBJECTIVES

The purpose of this work was to examine the effects of HIV infection and the impact of highly active antiretroviral treatment with protease inhibitors on neurodevelopmental functioning during the first 3 years of life.

PATIENTS AND METHODS

Pediatric AIDS Clinical Trials Group 219/219C is a longitudinal cohort study that has enrolled HIV-infected (HIV+) and HIV-exposed but uninfected (HIV-) infants and children since 1993. Longitudinal profiles of neurodevelopmental functioning as measured by the Bayley Scales of Infant Development were compared by HIV-infection status before and after the availability of highly active antiretroviral therapy with a protease inhibitor and within infants with Bayley tests available before and after initiating protease inhibitor therapy.

RESULTS

In the pre-protease inhibitor era, mean mental and motor scores in HIV+ (n = 54) infants <1 year of age were significantly lower than those among HIV- infants (n = 221) and remained lower up to 2 years of age. After protease inhibitors became available, mean mental and motor functioning of HIV+ infants (n = 91) <1 year of age were still significantly lower than those of HIV- infants (n = 838). However, against a background of declining scores among the HIV- infants, there was evidence of limited improvement in the HIV+ infants relative to their uninfected peers. Among infants who had Bayley II evaluations before and after starting a protease inhibitor, there was a trend to improved mental and motor scores after initiation of protease inhibitor therapy.

CONCLUSIONS

The suppression of systemic viral replication and subsequent substantial improvements in survival and immunologic status brought about by highly active antiretroviral therapy have been followed by limited improvements in neurodevelopmental functioning in young children. Additional longitudinal research is needed to better understand the role of antiretroviral therapy as well as the impact of genetic and environmental factors on neurodevelopmental functioning in children affected by HIV.

Immune reconstitution and predictors of virologic failure in adolescents infected through risk behaviors and initiating HAART: week 60 results from the PACTG 381 cohort

The responses to HAART in HIV-infected adolescents infected through risk behaviors are not well defined. PACTG 381 collected intensive immunologic and virologic data on youth naive to or with minimal exposure to antiretroviral therapy who began HAART. Subjects were evaluated according to their weeks 16-24 virologic response. Comparisons with a cohort of HIV-uninfected adolescents from the REACH cohort were performed. Cox proportional hazards models were used to identify baseline and week 24 predictors of virologic failure. Only 69 of 120 subjects (58%) achieved virologic suppression by weeks 16-24, whereas 55 of 69 (80%) demonstrated control to week 60. Higher CD4+ naive T cells (CD4+/62L+/RA+: hazard ratio [HR], 2.13; p = 0.018), higher CD8+ activated T cells (CD8+/CD38+/DR+: HR, 1.40, p = 0.028 per 100 cells/mm3) and higher CD8+ naive T cells (CD8+/62L+/RA+: HR, 1.72; p = 0.005) at weeks 16-24 in subjects with early viral success were predictive of subsequent failure. By week 60, total CD4+ T cells remained significantly lower than in uninfected controls. Adolescents beginning HAART achieve moderate rates of viral suppression by weeks 16-24. In those who do achieve early virologic control, suppression to week 60 is high although total CD4+ T cells remain significantly lower than in uninfected controls. Several T cell markers were predictive of subsequent virologic failure in subjects achieving short-term success. Further study is warranted to determine whether these predictors provide any benefit to clinical management.

Evaluation of compliance among nursing staff in administration of prescribed analgesic drugs to critically ill dogs and cats

OBJECTIVE

To investigate the prescription of analgesic drugs to hospitalized critically ill dogs and cats and determine compliance of nursing staff in administering the prescribed analgesics.

DESIGN

Cross-sectional study.

ANIMALS

272 dogs and 79 cats hospitalized in an intensive care unit during a 2-month period.

PROCEDURE

Patient treatment orders were examined daily for details regarding prescribed and administered analgesic drugs.

RESULTS

A mean of 39% of cats and dogs in the intensive care unit were prescribed analgesic drugs each day, the most common of which were opioids. Local anesthetic drugs, nonsteroidal anti-inflammatory drugs, and ketamine were prescribed less frequently. Cats were less likely than dogs to receive analgesics after traumatic injury, but the difference was not significant. There was no difference between species in frequency of prescription of analgesic drugs after surgery. Most patients were prescribed a single class of analgesic drug; only 13% had orders for multiple analgesics. Of the patients for which analgesics were prescribed, 64% received them exactly as prescribed, 23% had at least 1 reduction in dosing, and 13% had at least 1 increase in dosing. When a decrease in dosing occurred, the drugs were opioids in each instance, whereas when drug dosing was increased, the drugs were of various types.

CONCLUSIONS AND CLINICAL RELEVANCE

Discrepancies sometimes existed between the dose of analgesic prescribed and that administered. This appeared to occur primarily because of concerns about adverse effects of opioid drugs. Strategies to reduce these effects may improve pain management in critically ill dogs and cats.

GB virus C infection in children with perinatal human immunodeficiency virus infection

BACKGROUND

GB virus C (GBV-C) infection occurs in 20-40% of human immunodeficiency virus (HIV)-infected adults, and coinfection is associated with improved HIV disease outcome.

METHODS

To determine the prevalence of GBV-C infection in children who were perinatally infected with HIV, we conducted a cross-sectional prevalence survey in a cohort of perinatally infected HIV-positive children selected from a large, multicenter observational protocol. A blood specimen was obtained and tested for GBV-C viremia with the use of a qualitative GBV-C RNA assay and screened for past GBV-C infection with enzyme-linked immunosorbent assay to detect antibodies to the GBV-C envelope protein E2 (E2 Ab).

RESULTS

The 354 children who participated in the substudy were relatively healthy, with a median CD4 of 784 cells/mm and median HIV-1 viral load of 1055 copies/mL. The prevalence of GBV-C viremia was 20 of 353 or 5.7% (95% confidence interval, 3.5-8.6%), and the prevalence of E2 Ab was 12 of 354 or 3.4% (95% confidence interval, 1.8-5.8%). GBV-C viremic patients were older than patients without past GBV-C infection (median age, 12.8 years versus 10.7 years). Median CD4 lymphocyte counts were highest in subjects without GBV-C infection and lowest in those with E2 Ab.

CONCLUSIONS

GBV-C prevalence rates are lower in children with perinatal HIV infection than those reported for HIV-infected adults. With the exception of evidence that GBV-C viremic children had lower rates of Centers for Disease Control and Prevention HIV disease category C disease before GBV-C testing, we did not find evidence of improved HIV disease outcome in coinfected patients, but the number of HIV/GBV-C-coinfected children was small.

Growth of human immunodeficiency virus-infected children receiving highly active antiretroviral therapy

BACKGROUND

Weight and height growth of HIV-infected children tends to lag behind that of uninfected children of similar age. Previous reports of the effect of highly active antiretroviral therapy (HAART) on the growth of HIV-infected children have been contradictory.

METHODS

Age- and gender-adjusted height and weight z scores were studied for 192 HIV-infected children, 4 months to 17 years of age, who had been treated with antiretroviral therapy for at least 16 weeks. These children, in clinically and immunologically stable condition, were enrolled into one of 4 HAART regimens and evaluated for 96 weeks.

RESULTS

At baseline, these HIV-infected children were significantly shorter than uninfected children (mean z score, -0.57; 95% confidence interval, -0.73 to -0.41; P < 0.001). Children with greater viral loads at baseline were significantly shorter and lighter than children with smaller viral loads (both P < 0.001). Administration of HAART led to an increase in mean weight z scores to normal values (mean z score increase, from -0.16 to >0) by week 48 and an increase in mean height z scores of 72% toward normal values (mean z score increase, from -0.57 to -0.16) by week 96. Younger children gained height more rapidly (P < 0.001), and children with greater baseline viral loads gained weight more rapidly (P < 0.001). There was no evidence of differential height or weight changes in 48 weeks between children with different degrees of virologic control.

CONCLUSIONS

HAART improved the average weight gain of HIV-infected children from subnormal to normal after 1 year and improved average height growth to nearly normal after 2 years.

Hepatitis C Prevalence in Children With Perinatal Human Immunodeficiency Virus Infection Enrolled in a Long-term Follow-up Protocol

OBJECTIVE

To evaluate the prevalence of hepatitis C virus (HCV) infection in children with perinatal human immunodeficiency virus (HIV) infection.

DESIGN

Cross-sectional substudy.

SETTING

Multicenter study from 41 sites in the United States.

PATIENTS

Children with perinatal HIV infection were randomly selected from a large, long-term, follow-up protocol.

MAIN OUTCOME MEASURE

Hepatitis C infection was defined as having positive test results on both HCV antibody and HCV RNA assays.

RESULTS

Five hundred thirty children enrolled in the substudy; definitive HCV test results were available for 525 children. Eighty-three percent were of a minority race or ethnicity. They were equally distributed by sex, had a median age of 10.7 years, and were relatively healthy, with 75% having CD4+ lymphocyte counts greater than 500 cells/mm3. Eight of 525 children (1.5%; 95% confidence interval [CI], 0.7%-3.0%) infected with HIV were coinfected with HCV. In contrast, the rate of HCV infection in a serosurvey of more than 2700 children aged 6 to 11 years from the National Health and Nutrition Examination Survey was 0.2% (95% CI, 0.04%-0.6%). In our study, there were no differences between children coinfected with HIV and HCV and those without HCV infection in terms of demographic characteristics, CD4+ or CD8+ T-lymphocyte counts, HIV 1 RNA levels, preterm or mode of delivery, or liver disease; however, the number of children coinfected with HIV and HCV was small.

CONCLUSION

While HCV prevalence infection rates are low in children with perinatal HIV infection, they are 8 to 10 times higher than reported in HCV serosurveys of children in the United States.

Virologic and Immunologic Outcomes after 24 Weeks in HIV Type 1–Infected Adolescents Receiving Highly Active Antiretroviral Therapy

BACKGROUND

Adolescents represent the fastest growing demographic group of new human immunodeficiency virus (HIV) infections in the United States. At present, there is little information available about their response to therapy.

METHODS

We studied 120 adolescents infected via high-risk behaviors who began receiving highly active antiretroviral therapy (HAART), to determine their virologic and immunologic response to therapy.

RESULTS

Subjects were enrolled at 28 sites of the Pediatric Acquired Immunodeficiency Syndrome Clinical Trials Group. After 16-24 weeks of HAART, 59% of subjects had reproducible undetectable virus loads, according to repeat measurements (virologic success). As enumerated by flow-cytometric analysis, increases in levels of CD4 helper cells (both naive and memory) and decreases in levels of CD8 suppressor cells were observed. Partial restoration of some immunologic parameters for patients who did not achieve virologic success was also observed, but to a more limited extent than for adolescents with virologic success. Adherence to HAART was the only predictor of achieving undetectable virus loads.

CONCLUSIONS

Adolescents have the capacity to improve their immunologic status with HAART. Lower than expected success in virologic control is related to lack of adherence, and efforts to improve treatment outcome must stress measures to assure adherence to medication.

Delayed onset of pubertal development in children and adolescents with perinatally acquired HIV infection

OBJECTIVE

To examine whether greater severity of HIV infection is associated with delayed initiation of pubertal development among perinatally HIV-infected children, and to compare sexual maturation of perinatally HIV-infected children with children in the general US population using the National Health and Nutrition Examination Survey III.

METHODS

In a prospective cohort study, the authors studied 983 HIV-infected children aged 6 to 18 years, who had Tanner stage assessed on at least two occasions between 1995 and 2000. Analyses were conducted separately for girls and boys to identify factors associated with onset of puberty or adrenarche (progression beyond Tanner stage 1).

RESULTS

Among children who were in Tanner stage 1 at their first assessment, 185 of 413 (45%) girls and 144 of 434 (33%) boys entered puberty during the observation period. In multivariate longitudinal regression analyses adjusted for age, race/ethnicity, time interval between study visits, and other clinical factors, girls with severe immunosuppression (CD4% <15) were significantly less likely to enter adrenarche (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.29-0.83) and puberty (OR, 0.57; 95% CI, 0.33-0.96) compared with girls who were not immunosuppressed (CD4% > or =25). For boys, those with severe immunosuppression were significantly less likely to enter adrenarche (OR, 0.52; 95% CI, 0.28-0.96) and tended to be less likely to begin puberty (OR, 0.69; 95% CI, 0.39-1.22) compared with boys who were not immunosuppressed. Qualitative comparisons suggested that HIV-infected children may experience delayed puberty and adrenarche compared with similarly aged children in the general US population.

CONCLUSIONS

Immunosuppression was associated with delayed pubertal onset in perinatally HIV-infected children. Further studies of perinatally HIV-infected and uninfected children are needed to better quantify the delay in pubertal onset and to compare the pace of pubertal maturation.

Growth in human immunodeficiency virus-infected children receiving ritonavir-containing antiretroviral therapy

BACKGROUND

Human immunodeficiency virus (HIV)-infected children often suffer from impaired growth. Highly active antiretroviral therapy (HAART) successfully reduces HIV 1 (HIV-1) RNA to 400 copies/mL or less in many children.

OBJECTIVES

To determine if age- and sex-adjusted growth z scores correlate with HIV-1 RNA level and if control of viral load for 48 and 96 weeks results in improved growth in children receiving highly active antiretroviral therapy.

DESIGN

Secondary analysis of the cohort of children receiving ritonavir nested in a randomized, open-label, clinical trial.

SUBJECTS AND METHODS

The Pediatric AIDS Clinical Trials Group Protocol 338 enrolled clinically stable, antiretroviral therapy-experienced, HIV-infected subjects aged 2 through 17 years. Using data from subjects randomized to ritonavir-containing regimens (n = 197), the association of growth z scores and HIV-1 RNA levels were examined.

MAIN OUTCOME MEASURES

Age- and sex-adjusted weight and height z scores.

RESULTS

Enrollment weights were comparable with age- and sex-adjusted norms, but subjects receiving ritonavir-containing antiretroviral therapy were significantly shorter (mean z score, -0.57 [29th percentile]; 95% confidence interval, -0.73 to -0.40). Higher HIV-1 RNA levels correlated with lower growth z scores (P<.01). Subjects achieving and maintaining HIV-1 RNA of 400 copies/mL or less through 48 and 96 weeks experienced worse growth than subjects with a less controlled viral load.

CONCLUSIONS

In this pediatric cohort, a significant decline in height and weight z scores was found despite control of viral replication. Further studies of growth are necessary to assess if nutritional and hormonal adjuvants to highly active antiretroviral therapy should be considered to improve growth in HIV-infected children.

A local likelihood proportional hazards model for interval censored data

We discuss the use of local likelihood methods to fit proportional hazards regression models to right and interval censored data. The assumed model allows for an arbitrary, smoothed baseline hazard on which a vector of covariates operates in a proportional manner, and thus produces an interpretable baseline hazard function along with estimates of global covariate effects. For estimation, we extend the modified EM algorithm suggested by Betensky, Lindsey, Ryan and Wand. We illustrate the method with data on times to deterioration of breast cosmeses and HIV-1 infection rates among haemophiliacs.

Impact of protease inhibitor-containing combination antiretroviral therapies on height and weight growth in HIV-infected children

OBJECTIVE

To examine beneficial or detrimental effects of protease inhibitor (PI)-containing antiretroviral regimens on height and weight growth in children with human immunodeficiency virus (HIV) infection.

METHODS

A prospective cohort study was conducted of 906 HIV-infected children, from pediatric research clinics in the United States, who were between 3 months and 18 years of age and who had height and weight assessed in 1995 (before introduction of PIs in this population) and at least once more through 1999. Changes in age- and gender-adjusted height and weight growth associated with PI use were assessed.

RESULTS

Compared with a healthy reference population, children were more affected in height (mean z score: -0.90 [18th percentile]) than in weight (mean z score: -0.42 [34th percentile]) at baseline (1995). Two thirds of children received at least 1 PI during 1996 to 1999. In the multivariate mixed effects regression models adjusted for baseline log(10) CD4 cell count, baseline age, gender, and race/ethnicity, the use of PIs was associated with per-year gains of 0.13 z scores in height and 0.05 z scores in weight relative to the expected growth with non-PI-containing regimens (eg, after 1 year of PI use, a representative 6-year-old boy in our study would be approximately 0.7 cm taller and 0.1 kg heavier than if he had not received PIs). No significant differential effects of PIs on height or weight growth according to specific agents or children's sociodemographic or clinical characteristics were found.

CONCLUSIONS

Although the use of PI-containing regimens was not associated with growth retardation, it was associated with only small annual increments in height and weight growth in HIV-infected children.

HIV-1 RNA levels and development of clinical disease in two different adolescent populations

HIV infection rates in American youth continue to increase unabated. As adolescent-specific therapeutic interventions are planned, information on HIV infection's course and its predictors becomes critically important for valid and precise study design. We report on age-specific disease rates stratified by estimated time since infected and predictors of HIV disease progression through four clinical categories in two distinct adolescent populations. Adolescents with hemophilia infected through contaminated blood products showed disease progression rates of 18 to 23 events per 100 person-years (PYs) by age and years infected. Predictors of first progression included HIV-1 RNA >30,000 copies/ml (rate ratio [RR], 2.4; 95% confidence interval [CI], 1.5-3.9), antiretroviral monotherapy (RR, 2.4; 95% CI, 1.7-3.3); Latino/a ethnicity (RR, 2.2; 95% CI, 1.2-4.2) and initial intermediate clinical status (RR, 1.9; 95% CI, 1.3-2.9). Sexually-infected adolescents >18 years who had been infected >3 to 6 years had a disease progression rate of 16 events per 100 PY. For these youths, the sole predictor of first progression was viral load (VL) (RR for VL >30,000 copies per ml, 8.4; 95% CI, 2.8-25.1). This article examines the predictive capacity of viral load and evaluates other cofactors for disease progression in different adolescent populations. These data will be of value in clinical trial design.

Paraplegin gene analysis in hereditary spastic paraparesis (HSP) pedigrees in northeast England

OBJECTIVE

To identify the frequency and characterize the phenotype of paraplegin mutations in the hereditary spastic paraparesis (HSP) population in the northeast of England.

BACKGROUND

HSP is a disorder that shows both clinical and genetic heterogeneity. To date, 13 loci have been associated with an HSP phenotype, with the causative gene having been identified in four of these. Two autosomal genes have been identified, paraplegin and spastin, and two X-linked genes have been identified, L1CAM (cell adhesion molecule) and proteolipid protein.

METHODS

Thirty HSP pedigrees from the northeast of England were analyzed for mutation in each of the 17 exons of the paraplegin gene.

RESULTS

A single family with a paraplegin mutation was identified in which the paraplegin mutation co-segregates with an HSP phenotype in an apparent dominant manner. The authors also describe frequent polymorphism in the paraplegin gene in both the HSP and control populations.

CONCLUSION

Mutations in the paraplegin gene are not a common cause of HSP in the northeast of England. The phenotype of the paraplegin-related HSP family described had several striking features including amyotrophy, raised creatine kinase, sensorimotor peripheral neuropathy, and oxidative phosphorylation defect on muscle biopsy.

Correlates of opportunistic infections in children infected with the human immunodeficiency virus managed before highly active antiretroviral therapy

BACKGROUND

Opportunistic infections (OIs) are an important cause of morbidity and mortality in children infected with HIV. However, few data are available regarding the overall prevalence, incidence and immunologic correlates associated with these diseases in the pediatric HIV population. The Pediatric AIDS Clinical Trials Group (PACTG) has conducted multicenter studies in HIV-infected children since 1988 and through these studies has collected prospective data on the immunologic and virologic status of study participants and recorded complications, including infectious diseases, related to HIV infection and its treatments. Therefore data were analyzed from across 13 PACTG studies, performed before treatment with highly active antiretroviral therapy was given, to determine the rates of various infectious complications and the immunologic correlates, specifically CD4 cell counts, associated with these diseases.

RESULTS

OIs were tabulated from 3331 HIV-infected children who participated in 13 clinic trials undertaken before highly effective antiretroviral therapy was available. Five OIs occurred at event rates of >1.0 per 100 patient years (person years): serious bacterial infections, 15.1; herpes zoster, 2.9; disseminated Mycobacterium avium complex (DMAC), 1.8; Pneumocystis carinii pneumonia, 1.3; and tracheobronchial and esophageal candidiasis, 1.2. Six other OIs evaluated, cytomegalovirus (CMV) disease, cryptosporidiosis, tuberculosis, systemic fungal infections, toxoplasmosis and progressive multifocal leukoencephalopathy, occurred at event rates of <1.0 per 100 person years. Pneumonia (11.1 per 100 person years) and bacteremia (3.3 per 100 person years) were the most common bacterial infections. An AIDS-defining OI before entry was a risk factor for the development of a new OI during a trial. Bacterial infections, herpes zoster and tuberculosis occurred frequently at all stages of HIV infection; whereas DMAC, P. carinii pneumonia, CMV and other OIs occurred primarily in children with severe immunosuppression.

CONCLUSIONS

The frequency of OIs in HIV-infected children in the pre-highly active antiretroviral therapy era varies with age, pathogen, prior OI and immunologic status. Analysis of CD4 counts at the time of DMAC, CMV and PCP provide validation for current prophylaxis guidelines in children > or =2 years old. This information on infectious complications of pediatric HIV will be especially valuable for contemporary management of HIV infection that is poorly responsive to highly active antiretroviral therapy.

Serologic examination of hepatitis B infection and immunization in HIV-positive youth and associated risks. The Pediatric AIDS Clinical Trials Group Protocol 220 Team

This seroprevalence report examines serologic evidence of hepatitis B immunization or infection and associated demographic/behavioral factors in adolescent (aged 12-20) subjects enrolled in a nontherapeutic clinical trial at 43 Pediatric AIDS Clinical Trials Group (PACTG) clinical centers. Subjects (n = 94) infected with the human immunodeficiency virus (HIV) through sexual activity were categorized as hepatitis B virus (HBV)-immunized, HBV-infected, or nonimmune by hepatitis B serology performed on specimens collected within the subject's first 48 weeks on study (1993-1995). Sixteen percent of the 94 serologically classified subjects were immunized; 19% HBV-infected; 65% nonimmune. Of the three risk factor scores examined (sociodemographic, sexual, and substance abuse), substance use alone demonstrated a significant difference among groups (despite virtually no reported injecting drug behavior), with the sexual risk score exhibiting marginally significant differences. Logistic regression analysis (restricted to nonimmunized subjects) showed that male-male sexual activity raised the odds of HBV infection by a factor of 5.14 (95% confidence interval [CI]: 1.45-18. 23) relative to heterosexual activity; and that for every one point increase on the substance abuse risk scale the odds of infection increased 5% (95% CI: 0.99-1.10). The HBV infection rate in PACTG 220 HIV-positive females is twice United States population-based rates; the rate in PACTG 220 HIV-positive males is nearly seven times higher. Past immunization efforts in this population appear to have been based on sexual activity volume without regard to injecting-drug use in sex partners.

Treatment-mediated changes in human immunodeficiency virus (HIV) type 1 RNA and CD4 cell counts as predictors of weight growth failure, cognitive decline, and survival in HIV-infected children

This meta-analysis of 5 large studies of the Pediatric AIDS Clinical Trials Group was undertaken to evaluate the predictive value of antiretroviral treatment-mediated changes in 3 markers of human immunodeficiency virus (HIV) type 1 disease progression-HIV-1 RNA level, CD4 cell count, and CD4 percentage-for weight growth failure, cognitive decline, and survival in HIV-infected children. Proportional hazards models were used to assess the prognostic value of the markers at baseline and after 24 weeks of treatment, with data from 1089 children. Among children receiving nucleoside with or without nonnucleoside reverse-transcriptase inhibitors, higher immunologic and lower virologic markers at baseline and after 24 weeks were significant independent predictors of survival, whereas virologic markers were significant predictors of weight growth and cognitive failure in children >1 year old. The finding of differential age effects on pediatric-specific clinical outcomes emphasizes the need for continued investigation of treatment effects in children.