Approaches to protocol standardization and data harmonization in the ECHO-wide cohort study.

The United States (U.S.) National Institutes of Health-funded Environmental influences on Child Health Outcomes (ECHO)-wide Cohort was established to conduct high impact, transdisciplinary science to improve child health and development. The cohort is a collaborative research design in which both extant and new data are contributed by over 57,000 children across 69 cohorts. In this review article, we focus on two key challenging issues in the ECHO-wide Cohort: data collection standardization and data harmonization. Data standardization using a Common Data Model and derived analytical variables based on a team science approach should facilitate timely analyses and reduce errors due to data misuse. However, given the complexity of collaborative research designs, such as the ECHO-wide Cohort, dedicated time is needed for harmonization and derivation of analytic variables. These activities need to be done methodically and with transparency to enhance research reproducibility. IMPACT: Many collaborative research studies require data harmonization either prior to analyses or in the analyses of compiled data. The Environmental influences on Child Health Outcomes (ECHO) Cohort pools extant data with new data collection from over 57,000 children in 69 cohorts to conduct high-impact, transdisciplinary science to improve child health and development, and to provide a national database and biorepository for use by the scientific community at-large. We describe the tools, systems, and approaches we employed to facilitate harmonized data for impactful analyses of child health outcomes.

Associations between cord blood acetaminophen biomarkers and childhood asthma with and without allergic comorbidities.

BACKGROUND: Previous studies have linked prenatal acetaminophen use to increased asthma risk in children. However, none have explored this association while differentiating between asthma cases with and without other allergic conditions or by employing objective biomarkers to assess acetaminophen exposure. OBJECTIVE: To evaluate whether the detection of acetaminophen biomarkers in cord blood is associated with the subgroups of asthma both with and without allergic comorbidities in children. METHODS: Acetaminophen biomarkers, including unchanged acetaminophen and acetaminophen glucuronide, were measured in neonatal cord blood samples from the Boston Birth Cohort. Asthma subgroups were defined on the basis of physician diagnoses of asthma and other allergic conditions (atopic dermatitis and allergic rhinitis). Multinomial regressions were used to evaluate the associations between acetaminophen biomarkers and asthma subgroups, adjusting for multiple confounders, including potential indications for maternal acetaminophen use such as maternal fever. RESULTS: The study included 142 children with asthma and at least 1 other allergic condition, 55 children with asthma but no other allergic condition, and 613 children free of asthma. Detection of acetaminophen in cord blood, reflecting maternal exposure to acetaminophen shortly before delivery, was associated with 3.73 times the odds of developing asthma without allergic comorbidities (95% CI: 1.79-7.80, P = .0004). In contrast, the detection of acetaminophen in cord blood was not associated with an elevated risk of asthma with allergic comorbidities. Analysis of acetaminophen glucuronide yielded consistent results. CONCLUSION: In a prospective birth cohort, cord blood acetaminophen biomarkers were associated with an increased risk of childhood asthma without allergic comorbidities, but were not associated with childhood asthma with allergic comorbidities.

No Association of IFNL4 Genotype With Opportunistic Infections and Cancers Among Men With Human Immunodeficiency Virus 1 Infection.

BACKGROUND: IFNL4 genetic variants that are strongly associated with clearance of hepatitis C virus have been linked to risk of certain opportunistic infections (OIs) and cancers, including Kaposi sarcoma, cytomegalovirus infection, and herpes simplex virus infection. As the interferon (IFN) λ family plays a role in response to viral, bacterial, and fungal infections, IFNL4 genotype might affect risk for a wide range of OIs/cancers. METHODS: We examined associations between genotype for the functional IFNL4 rs368234815 polymorphism and incidence of 16 OIs/cancers among 2310 men with human immunodeficiency virus (2038 white; 272 black) enrolled in the Multicenter AIDS Cohort Study during 1984-1990. Our primary analyses used Cox proportional hazards models adjusted for self-reported racial ancestry to estimate hazard ratios with 95% confidence intervals, comparing participants with the genotypes that generate IFN-λ4 and those with the genotype that abrogates IFN-λ4. We censored follow-up at the introduction of highly effective antiretroviral therapies. RESULTS: We found no statistically significant association between IFNL4 genotype and the incidence of Kaposi sarcoma (hazard ratio, 0.92 [95% confidence interval, .76-1.11]), cytomegalovirus infection (0.94 [.71-1.24]), herpes simplex virus infection (1.37 [.68-2.93]), or any other OI/cancer. We observed consistent results using additive genetic models and after controlling for CD4 cell count through time-dependent adjustment or restriction to participants with a low CD4 cell count. CONCLUSIONS: The absence of associations between IFNL4 genotype and these OIs/cancers provides evidence that this gene does not affect the risk of disease from opportunistic pathogens.

Meta-analysis under imbalance in measurement of confounders in cohort studies using only summary-level data.

BACKGROUND: Cohort collaborations often require meta-analysis of exposure-outcome association estimates across cohorts as an alternative to pooling individual-level data that requires a laborious process of data harmonization on individual-level data. However, it is likely that important confounders are not all measured uniformly across the cohorts due to differences in study protocols. This imbalance in measurement of confounders leads to association estimates that are not comparable across cohorts and impedes the meta-analysis of results. METHODS: In this article, we empirically show some asymptotic relations between fully adjusted and unadjusted exposure-outcome effect estimates, and provide theoretical justification for the same. We leverage these results to obtain fully adjusted estimates for the cohorts with no information on confounders by borrowing information from cohorts with complete measurement on confounders. We implement this novel method in CIMBAL (confounder imbalance), which additionally provides a meta-analyzed estimate that appropriately accounts for the dependence between estimates arising due to borrowing of information across cohorts. We perform extensive simulation experiments to study CIMBAL's statistical properties. We illustrate CIMBAL using National Children's Study (NCS) data to estimate association of maternal education and low birth weight in infants, adjusting for maternal age at delivery, race/ethnicity, marital status, and income. RESULTS: Our simulation studies indicate that estimates of exposure-outcome association from CIMBAL are closer to the truth than those from commonly-used approaches for meta-analyzing cohorts with disparate confounder measurements. CIMBAL is not too sensitive to heterogeneity in underlying joint distributions of exposure, outcome and confounders but is very sensitive to heterogeneity of confounding bias across cohorts. Application of CIMBAL to NCS data for a proof-of-concept analysis further illustrates the utility and advantages of CIMBAL. CONCLUSIONS: CIMBAL provides a practical approach for meta-analyzing cohorts with imbalance in measurement of confounders under a weak assumption that the cohorts are independently sampled from populations with the same confounding bias.

Social inequalities contribute to racial/ethnic disparities in depressive symptomology among men who have sex with men.

PURPOSE: Racial/ethnic minorities experience disproportionate rates of depressive symptoms in the United States. The magnitude that underlying factors-such as social inequalities-contribute to these symptoms is unknown. We sought to identify exposures that explain racial/ethnic differences in clinically significant depressive symptomology among men who have sex with men (MSM). METHODS: Data from the Multicenter AIDS Cohort Study (MACS), a prospective cohort study, were used to examine clinically significant symptoms of depression (Center for Epidemiologic Studies Depression Scale score ≥ 20) among non-Latinx White, non-Latinx Black, and Latinx MSM. We included 44,823 person-visits by 1729 MSM seen in the study sites of Baltimore/Washington, DC; Chicago; Pittsburgh/Columbus; and Los Angeles from 2000 to 2017. Regression models estimated the percentage of depressive symptom risk explained by social, treatment, and health-related variables related to race/ethnicity. Machine-learning methods were used to predict the impact of mitigating differences in determinants of depressive symptoms by race/ethnicity. RESULTS: At the most recent non-missing MACS visit, 16% of non-Latinx White MSM reported clinically significant depressive symptoms, compared to 22% of non-Latinx Black and 25% of Latinx men. We found that income and social-environmental stress were the largest contributors to racial/ethnic disparities in risk for depressive symptoms. Similarly, setting the prevalence of these two exposures to be equal across racial/ethnic groups was estimated to be most effective at reducing levels of clinically significant depressive symptoms. CONCLUSION: Results suggested that reducing socioeconomic inequalities and stressful experiences may be effective public health targets to decrease racial/ethnic disparities in depressive symptoms among MSM.

Inflammation and Risk of Depression in HIV: Prospective Findings From the Multicenter AIDS Cohort Study.

Studies suggest that inflammation might be involved in the pathogenesis of depression. Individuals with human immunodeficiency virus (HIV) have a higher risk of depression and elevated inflammatory profiles. Despite this, research on the link between inflammation and depression among this high-risk population is limited. We examined a sample of men who have sex with men from the Multicenter AIDS Cohort Study in prospective analyses of the association between inflammation and clinically relevant depression symptoms, defined as scores >20 on Center for Epidemiological Studies Depression Scale. We included 1,727 participants who contributed 9,287 person-visits from 1984 to 2010 (8,218 with HIV (HIV+) and 1,069 without (HIV-)). Exploratory factor analysis (EFA) was used to characterize underlying inflammatory processes from 19 immune markers. Logistic regression with generalized estimating equations was used to evaluate associations between inflammatory processes and depressive symptoms stratified by HIV serostatus. Three EFA-identified inflammatory processes (EIPs) were identified. EIP-1 scores-described by soluble tumor necrosis factor receptor 2 (sTNF-R2), soluble interleukin-2 receptor α (sIL-2Rα), sCD27, B-cell activating factor, interferon γ-induced protein 10 (IP-10), soluble interleukin-6 receptor (sIL-6R), sCD14, and sGP130-were significantly associated with 9% higher odds of depressive symptoms in HIV+ participants (odds ratio = 1.09; 95% confidence interval: 1.03, 1.16) and 33% higher odds in HIV- participants (odds ratio = 1.33; 95% confidence interval: 1.09, 1.61). Findings suggest that immune activation might be involved in depression risk among both HIV+ and HIV- men who have sex with men.

Optimal metrics for identifying long term patterns of depression in older HIV-infected and HIV-uninfected men who have sex with men.

OBJECTIVES: Center of Epidemiologic Studies-Depression Scale (CES-D) provides a snapshot of symptom severity at a single point in time. However, the best way of using CES-D to classify long-term depression is unclear. METHOD: To identify long-term depression among HIV-infected and HIV-uninfected 50+ year-old men who have sex with men (MSM) with at least 5 years of follow-up, we compared sensitivities and specificities of CES-D-based metrics (baseline CES-D; four consecutive CES-Ds; group-based trajectory models) thresholded at 16 and 20 to a clinician's evaluation of depression phenotype based on all available data including CES-D history, depression treatment history, drug use history, HIV disease factors, and demographic characteristics. RESULTS: A positive depressive phenotype prevalence was common among HIV-infected (prevalence = 33.1%) and HIV-uninfected MSM (prevalence = 23.2%). Compared to the depressive phenotype, trajectory models of CES-D≥20 provided highest specificities among HIV-infected (specificity = 99.9%, 95% Confidence Interval [CI]:99.4%-100.0%) and HIV-uninfected MSM (specificity = 99.0%, 95% CI:97.4%-99.7%). Highest sensitivities resulted from classifying baseline CES-D ≥ 16 among HIV-infected MSM (sensitivity = 75.0%, 95% CI:67.3%-81.7%) and four consecutive CES-Ds ≥ 16 among HIV-uninfected MSM (sensitivity = 81.0%, 95% CI:73.7%-87.0%). CONCLUSION: Choice of method should vary, depending on importance of false positive or negative rate for long-term depression in HIV-infected and HIV-uninfected MSM.

An Environmental influences on Child Health Outcomes viewpoint of data analysis centers for collaborative study designs.

PURPOSE OF REVIEW: A highly complex collaborative study design that pools and extends existing studies, such as the Environmental influences on Child Health Outcomes (ECHO) Program, requires a Data Analysis Center (DAC) with resources and expertise to create a secure environment for housing and analyzing the shared data, harmonize and structure the shared data for different purposes, and apply appropriate and innovative designs and analytic methods. The DAC, in partnership with cohort investigators, must ensure that results from ECHO-wide cohort analyses are appropriately interpreted and reproducible. RECENT FINDINGS: Understanding the cohorts contributing to ECHO is critical for developing a collaborative environment and the methods to best analyze the data without bias. We further describe the development of the ECHO-wide cohort Metadata Catalog, the architecture of the ECHO-wide cohort data platform, and analytical approaches to facilitate early productivity. SUMMARY: The ECHO DAC has established a secure environment for the transfer and storage of ECHO cohort data and information, and initiated processes to promote productive collaborations. Understanding the ECHO DAC responsibilities and assets will help to overcome communication and trust challenges encountered in the initiation of this complex ECHO-wide cohort collaborative research study.

Systemic Inflammation Characterizes Lack of Metabolic Health in Nonobese HIV-Infected Men.

BACKGROUND: Increasing body mass index (BMI) is generally associated with loss of metabolic health, although some obese individuals remain metabolically healthy. Among nonobese men, HIV infection has been associated with a lower prevalence of metabolic health. METHODS: We conducted a cross-sectional analysis of 470 HIV-infected and 368 HIV-uninfected men enrolled in the Multicenter AIDS Cohort Study Cardiovascular substudy. Circulating biomarker levels were compared by BMI category and by HIV serostatus. Poisson regression with robust variance determined associations between metabolic health and circulating inflammatory biomarker levels after adjusting for factors previously associated with metabolic health. RESULTS: HIV-infected men were younger and less likely to be obese. Among HIV-infected, normal weight metabolically healthy men (compared to unhealthy) had significantly lower circulating levels of interleukin- (IL-) 6, soluble tumor necrosis factor receptors (sTNFR) I and II, and homeostatic model assessment of insulin resistance (HOMA-IR), higher adiponectin, less visceral fat, and more subcutaneous fat. Among HIV-uninfected normal weight men and obese men (regardless of HIV serostatus), metabolic health was associated only with higher levels of adiponectin, less visceral fat, and lower HOMA-IR values. In multivariate analyses restricted to HIV-infected men, lower hs-CRP, sTNFRI, sTNFRII, and HOMA-IR and higher adiponectin levels were associated with metabolic health. Additional adjustment for visceral adiposity did not alter results. CONCLUSIONS: Among HIV-infected normal weight men, metabolic health was associated with less systemic inflammation, a relationship that, among normal weight men, was unique to HIV+ men and did not exist among obese men of either HIV serostatus.

Inflammation, Immune Activation, Immunosenescence, and Hormonal Biomarkers in the Frailty-Related Phenotype of Men With or at Risk for HIV Infection.

Background: The extent to which inflammation, immune activation/immunosenescence, and hormonal abnormalities are driven by human immunodeficiency virus (HIV) or frailty is not clear. Methods: HIV-infected frail men (n = 155) were matched to nonfrail, HIV-infected (n = 141) and HIV-uninfected (n = 150) men by age, calendar year, and antiretroviral therapy use (HIV-infected men only). Frailty was defined by ≥3 frailty-related phenotype criteria (weight loss, exhaustion, low activity, slowness) at ≥2 visits, or at 1 visit with ≥1 criteria at ≥2 visits. The following measurements were obtained: interleukin 6, high-sensitivity C-reactive protein, soluble receptors for tumor necrosis factor α 1 and 2, the percentages of CD4+CD28-, CD8+CD28-, CD4+CD38+HLA-DR+, and CD8+CD38+HLA-DR+ T cells, dehydroepiandrosterone sulfate, free testosterone, homeostatic model assessment of insulin resistance, and insulin-like growth factor 1. Log-linear regressions were adjusted for a priori selected covariates to determine differences by frailty and HIV status. Results: In multivariate analyses adjusted for covariates, frailty was associated among HIV-infected men with higher interleukin 6 and high-sensitivity C-reactive protein and lower free testosterone and dehydroepiandrosterone levels. In contrast, HIV infection but not frailty was associated with significantly greater immune senescence (percentage of CD4+CD28- or CD8+CD28- T cells) and immune activation (percentages of CD4+CD38+HLA-DR+ and CD8+CD38+HLA-DR+ T cells). Conclusions: Frailty among HIV-infected men was associated with increased inflammation and lower hormone levels, independent of comorbid conditions. Interventions targeting these pathways should be evaluated to determine the impact on prevention or reversal of frailty among HIV-infected men.

Association of long-term patterns of depressive symptoms and attention/executive function among older men with and without human immunodeficiency virus.

Older HIV-infected men are at higher risk for both depression and cognitive impairments, compared to HIV-uninfected men. We evaluated the association between longitudinal patterns of depressive symptoms and attention/executive function in HIV-infected and HIV-uninfected men aged 50+ years to understand whether HIV infection influenced the long-term effect of depression on attention/executive function. Responses to the Center for Epidemiologic Studies-Depression scale and attention/executive function tests (Trail Making Test Part B and Symbol Digit Modalities Test) were collected semiannually from May 1986 to April 2015 in 1611 men. Group-based trajectory models, stratified by HIV status, were used to identify latent patterns of depressive symptoms and attention/executive function across 12 years of follow-up. We identified three depression patterns for HIV-infected and HIV-uninfected men (rare/never 50.0 vs. 60.6%, periodically depressed 29.6 vs. 24.5%, chronic high 20.5 vs.15.0%, respectively) and three patterns of attention/executive function for HIV-infected and HIV-uninfected men (worst-performing 47.4 vs. 45.1%; average 41.9 vs. 47.0%; best-performing 10.7 vs. 8.0%, respectively). Multivariable logistic regression models were used to assess associations between depression patterns and worst-performing attention/executive function. Among HIV-uninfected men, those in the periodically depressed and chronic high depressed groups had higher odds of membership in the worst-performing attention/executive function group (adjusted odds ratio [AOR] = 1.45, 95% CI 1.04, 2.03; AOR = 2.25, 95% CI 1.49, 3.39, respectively). Among HIV-infected men, patterns of depression symptoms were not associated with patterns of attention/executive function. Results suggest that HIV-uninfected, but not HIV-infected, men with chronic high depression are more likely to experience a long-term pattern of attention/executive dysfunction.

Multiplex assay reliability and long-term intra-individual variation of serologic inflammatory biomarkers.

BACKGROUND: Circulating cytokines, chemokines, and soluble cytokine receptors can serve as biomarkers of inflammation and immune dysregulation. Good reliability of multiplex platforms, which allow for simultaneous, comprehensive biomarker assessment, is critical for their utility in epidemiologic studies. We examined the reliability of the Meso-Scale Discovery (MSD) platform to simultaneously quantitate 15 cytokines and chemokines and the Luminex platform (R&D Systems) to quantitate 5 soluble receptors and 2 chemokines and cytokines and evaluated long-term within-person correlation of these biomarkers. METHODS: The detectability and reliability of these assay systems were assessed using the same external controls across plates and archived sera from 250 HIV- men in the Multicenter AIDS Cohort Study. Using up to four visits per person from 1984 to 2009, age-adjusted intraclass correlation coefficients (ICC) of biomarkers with >80% detectability (CCL11, CXCL8, CXCL10, CCL2, CCL4, CCL13, CCL17, CXCL13, IL-10, IL-12p70, IL-6, TNF-α, BAFF, sCD14, sCD27, sgp130, sIL-2Rα, and sTNF-R2) were obtained using linear mixed models. RESULTS: Most biomarkers were detectable in 80% of control samples; IFN-γ, GM-CSF, and IL-2 were undetectable in >20% of samples. Among the HIV-uninfected men, most biomarkers showed fair to strong within-person correlation (ICC>0.40) up to 15years. The ICC for CXCL8 was good in the short term but decreased with increasing time between visits, becoming lower (ICC<0.40) after 8years. CONCLUSIONS: These multiplexed assays showed acceptable reliability for use in epidemiologic research, despite some technical variability and limitations in cytokine quantitation. Most biomarkers displayed moderate-to-excellent intra-individual variability over the long term, suggesting their utility in prospective studies investigating etiologic associations with diverse chronic conditions.

Unsafe Sexual Behavior Among Gay/Bisexual Men in the Era of Combination Antiretroviral Therapy (cART).

The aim of this study was to determine the association between psychosocial determinants of unprotected receptive anal intercourse (URAI) and unprotected insertive anal intercourse (UIAI). Data from 417 HIV positive men who have sex with men (MSM) in the Multicenter AIDS Cohort Study from April 1999 to March 2012 were analyzed and adjusted odds were calculated. It was found that 66% (n = 277) and 72% (n = 299) reported any UIAI or URAI over follow-up, respectively. Cumulative cART-years (median = 5.30 years) was associated with 33 and 47% increases in UIAI and URAI, respectively. Not having reduced concern about HIV transmission (UIAI: OR 0.37, p-value = 0.0004; URAI: OR 0.57, p-value = 0.04), increased safe sex fatigue (UIAI: OR 2.32, 95% p-value = 0.0002; URAI: OR 1.94, p-value = 0.003), and sexual sensation seeking (UIAI: OR 1.76, p-value = 0.002; URAI: OR 1.56, p-value = 0.02) were associated with UIAI and URAI. Serosorting was associated with UIAI (OR 6.11, p-value < 0.0001) and URAI (OR 6.80, p-value < 0.0001). Findings suggest that negative attitudes about HIV transmission are sustained among older men who have sex with men.

Inflammatory Biomarkers and Mortality Risk Among HIV-Suppressed Men: A Multisite Prospective Cohort Study.

BACKGROUND: Human immunodeficiency virus (HIV)-induced inflammation and immune activation persist after initiation of combination antiretroviral therapy (cART) and HIV suppression and may contribute to mortality risks that exceed those in HIV-uninfected populations, though associations are unclear. METHODS: In the prospective Multicenter AIDS Cohort Study, comprising men who have sex with men from Baltimore, Chicago, Los Angeles, and Pittsburgh, concentrations of 24 biomarkers of inflammation and immune activation were measured in stored serum from HIV-positive men obtained after cART-induced HIV suppression between 1996 and 2009. The outcome was nonaccidental death, with follow-up until 2014. We used Cox proportional hazards models to test whether biomarker concentrations predict time from HIV suppression to death and adjusted for multiple tests. Exploratory factor analysis (EFA) was employed to identify groupings of biomarkers that predict mortality risk. RESULTS: Of 670 men followed up from HIV suppression, 54 died by the end of 2013. After adjustment for age, CD4(+) cell count, hepatitis B or C virus infection, and smoking, concentrations in the highest quartile of 4 biomarkers were significantly associated with mortality risk after controlling the false discovery rate at 5%: interleukin (IL) 6 (hazard ratio, 3.54; 95% confidence interval, 2.06-6.10), soluble IL 2Rα (3.29, 1.85-5.85), soluble CD14 (2.67, 1.55-4.61), and chemokine (CXC motif) ligand 13 (CXCL13; 2.26; 1.29-3.95). EFA yielded 2 biomarker groupings that were independent predictors of mortality risk. CONCLUSIONS: Despite having undetectable HIV RNA levels during cART, men with higher concentrations of several biomarkers (particularly IL 6, soluble IL 2Rα, soluble CD14, and CXCL13) had higher hazards of long-term mortality. Correlations observed among biomarker concentrations may represent underlying inflammatory processes that contribute to mortality risk.

Suboptimal Adherence to Combination Antiretroviral Therapy Is Associated With Higher Levels of Inflammation Despite HIV Suppression.

BACKGROUND: Human immunodeficiency virus (HIV)-infected individuals exhibit residual inflammation regardless of virologic suppression. We evaluated whether suboptimal adherence to combination antiretroviral therapy (cART) is associated with greater residual inflammation than optimal adherence, despite virologic suppression. METHODS: Longitudinal self-reported cART adherence data and serum concentrations of 24 biomarkers of inflammation and immune activation were measured at the same study visit in HIV RNA-suppressed (<50 copies/mL) HIV-infected men in the Multicenter AIDS Cohort Study from 1998 to 2009. Associations between dichotomized 6-month (<100% vs 100%) and categorized 4-day (<85%, 85%-99%, and 100%) cART adherence with biomarker concentrations were evaluated. RESULTS: A total of 912 men provided 2816 person-visits with documented plasma HIV RNA suppression. In adjusted models, person-visits at which <100% cART 6-month adherence was reported had higher concentrations of interleukin 2, 6, and 10, interferon γ, tumor necrosis factor α, and C-reactive protein than person-visits at which 100% cART adherence (P < .05) was reported. These same differences were observed in person-visits reporting <85% versus 100% 4-day cART adherence, but not in visits reporting 85%-99% versus 100% cART adherence. After adjustment for multiple comparisons, tumor necrosis factor α remained significantly higher (11% increase; P < .001) in person-visits at which <100% adherence was reported. CONCLUSIONS: Higher concentrations of inflammatory biomarkers were observed among HIV RNA-suppressed men who reported <100% cART adherence than among more adherent men. Residual HIV replication (ie, below the limit of detection), more likely among men with suboptimal adherence, is a plausible mechanism. Whether improving cART adherence could affect residual inflammation and associated morbidity and mortality rates should be investigated.

HIV Infection, Tenofovir, and Urine α1-Microglobulin: A Cross-sectional Analysis in the Multicenter AIDS Cohort Study.

BACKGROUND: Tenofovir disoproxil fumarate (TDF) can cause proximal tubular damage and chronic kidney disease in human immunodeficiency virus (HIV)-infected individuals. Urine α1-microglobulin (A1M), a low-molecular-weight protein indicative of proximal tubular dysfunction, may enable earlier detection of TDF-associated tubular toxicity. STUDY DESIGN: Cross-sectional. SETTING & PARTICIPANTS: 883 HIV-infected and 350 -uninfected men enrolled in the Multicenter AIDS Cohort Study. PREDICTORS: HIV infection and TDF exposure. OUTCOME: Urine A1M level. RESULTS: Urine A1M was detectable in 737 (83%) HIV-infected and 202 (58%) -uninfected men (P<0.001). Among HIV-infected participants, 573 (65%) were current TDF users and 112 (13%) were past TDF users. After multivariable adjustment including demographics, traditional kidney disease risk factors, and estimated glomerular filtration rate, HIV infection was associated with 136% (95% CI, 104%-173%) higher urine A1M levels and 1.5-fold (95% CI, 1.3- to 1.6-fold) prevalence of detectable A1M. When participants were stratified by TDF exposure, HIV infection was associated with higher adjusted A1M levels, by 164% (95% CI, 127%-208%) among current users, 124% (95% CI, 78%-183%) among past users, and 76% (95% CI, 45%-115%) among never users. Among HIV-infected participants, each year of cumulative TDF exposure was associated with 7.6% (95% CI, 5.4%-9.9%) higher A1M levels in fully adjusted models, a 4-fold effect size relative to advancing age (1.8% [95% CI, 0.9%-2.7%] per year). Each year since TDF treatment discontinuation was associated with 4.9% (95% CI, -9.4%--0.2%) lower A1M levels among past users. LIMITATIONS: Results may not be generalizable to women. CONCLUSIONS: HIV-infected men had higher urine A1M levels compared with HIV-uninfected men. Among HIV-infected men, cumulative TDF exposure was associated with incrementally higher A1M levels, whereas time since TDF treatment discontinuation was associated with progressively lower A1M levels. Urine A1M appears to be a promising biomarker for detecting and monitoring TDF-associated tubular toxicity.

Host factors associated with serologic inflammatory markers assessed using multiplex assays.

Chronic systemic inflammation contributes to the development of adverse health conditions, yet the influence of fixed and modifiable risk factors on many serologic biomarkers of inflammation remains largely unknown. Serum concentrations of twenty-three biomarkers, including C-reactive protein (CRP), cytokines (CXCL11, CXCL8, CXCL10, CCL2, CCL13, CCL4, CCL17, CXCL13, IL-10, IL-12p70, IL-6, TNF-α, IL-2, IFN-γ, IL-1ß, GM-CSF, BAFF), and soluble immune receptors (sCD14, sIL-2Rα, sCD27, sgp130, sTNF-R2) were measured longitudinally using multiplexed immunometric assays in 250 HIV-uninfected men followed in the Multicenter AIDS Cohort Study (1984-2009). Generalized gamma regression was used to determine the statistical significance of factors associated with each biomarker. After accounting for age, race, and education, and for analysis of multiple biomarkers, higher concentrations of specific individual biomarkers were significantly (P<0.002) associated with hypertension, obesity, hepatitis C infection, stimulant use, and diabetes and lower concentrations with hypercholesterolemia. These associations should be taken into account in epidemiological studies of these biomarkers, and may provide potential targets for disease prevention and treatment.

Kidney Dysfunction and Markers of Inflammation in the Multicenter AIDS Cohort Study.

BACKGROUND: Human immunodeficiency virus (HIV)-infected individuals are at higher risk for chronic kidney disease than HIV-uninfected individuals. We investigated whether the inflammation present in treated HIV infection contributes to kidney dysfunction among HIV-infected men receiving highly active antiretroviral therapy. METHODS: The glomerular filtration rate (GFR) was directly measured (using iohexol) along with 12 markers of inflammation in Multicenter AIDS Cohort Study participants. Exploratory factor analysis was used to identify inflammatory processes related to kidney dysfunction. The estimated levels of these inflammatory processes were used in adjusted logistic regression analyses evaluating cross-sectional associations with kidney function outcomes. RESULTS: There were 434 HIV-infected men receiving highly active antiretroviral therapy and 200 HIV-uninfected men. HIV-infected men were younger (median age, 51 vs 53 years) and had higher urine protein-creatinine ratios (median, 98 vs 66 mg/g) but comparable GFRs (median, 109 vs 106 mL/min|1.73 m(2)). We found an inflammatory process dominated by markers: soluble tumor necrosis factor receptor 2, soluble interleukin 2 receptor α, soluble gp130, soluble CD27, and soluble CD14. An increase of 1 standard deviation in that inflammatory process was associated with significantly greater odds of GFR ≤90 mL/min/1.73 m(2) (odds ratio, 2.0) and urine protein >200 mg/g (odds ratio, 2.3). CONCLUSIONS: Higher circulating levels of immune activation markers among treated HIV-infected men may partially explain their higher burden of kidney dysfunction compared with uninfected men.

Elevated levels of monocyte activation markers are associated with subclinical atherosclerosis in men with and those without HIV infection.

BACKGROUND: Heightened immune activation among human immunodeficiency virus (HIV)-infected persons may contribute to atherosclerosis. We assessed associations of serologic markers of monocyte activation, soluble CD163 (sCD163) and soluble CD14 (sCD14), and monocyte chemoattractant protein 1 (CCL2) with subclinical atherosclerosis among men with and those without HIV infection in the Multicenter AIDS Cohort Study. METHODS: We performed noncontrast computed tomography on 906 men (566 HIV-infected men and 340 HIV-uninfected men), 709 of whom also underwent coronary computed tomographic angiography. Associations between each biomarker and the prevalence of coronary plaque, the prevalence of stenosis of ≥50%, and the extent of plaque were assessed by logistic and linear regression, adjusting for age, race, HIV serostatus, and cardiovascular risk factors. RESULTS: Levels of all biomarkers were higher among HIV-infected men, of whom 81% had undetectable HIV RNA, and were associated with lower CD4(+) T-cell counts. In the entire population and among HIV-infected men, higher biomarker levels were associated with a greater prevalence of coronary artery stenosis of ≥50%. Higher sCD163 levels were also associated with greater prevalences of coronary artery calcium, mixed plaque, and calcified plaque; higher CCL2 levels were associated with a greater extent of noncalcified plaque. CONCLUSIONS: sCD163, sCD14, and CCL2 levels were elevated in treated HIV-infected men and associated with atherosclerosis. Monocyte activation may increase the risk for cardiovascular disease in individuals with HIV infection.

High Oral Human Papillomavirus Type 16 Load Predicts Long-term Persistence in Individuals With or at Risk for HIV Infection.

The association between oral human papillomavirus 16 (HPV16) DNA load and infection clearance was evaluated among 88 individuals with oral HPV16 infection who were identified within a prospective cohort of 1470 HIV-infected and uninfected individuals. Oral rinse specimens were collected semiannually for up to 5 years. The oral HPV16 load at the time of the first positive test result was significantly associated with the time to clearance of infection (continuous P trends <.01). Notably, clearance rates by 24 months were 41% and 94% in the highest and lowest HPV16 load tertiles (P = .03), respectively. High oral HPV16 load warrants consideration as a biomarker for infection persistence, the presumed precursor of HPV16-associated oropharyngeal cancer.