Chenglong Liu

Assessing the effect of HAART on change in quality of life among HIV-infected women

BackgroundThe impact of highly active antiretroviral therapy (HAART) on health-related quality of life (QOL) of HIV-1 infected individuals in large prospective cohorts has not been well studied.ObjectiveTo assess the effect of HAART on QOL by comparing HIV-infected women using HAART with HIV-infected women remaining HAART naïve in the Womens Interagency HIV Study (WIHS), a multicenter prospective cohort study begun in 1994 in the US.MethodsA 1:1 matching with equivalent (≤ 0.1%) propensity scores for predicting HAART initiation was implemented and 458 pairs were obtained. HAART effects were assessed using pattern mixture models. The changes of nine QOL domain scores and one summary score derived from a shortened version of the MOS-HIV from initial values were used as study outcomes.ResultsThe background covariates of the treatment groups were well-balanced after propensity score matching. The 916 matched subjects had a mean age of 38.5 years and 42% had a history of AIDS diagnosis. The participants contributed a total of 4,292 person visits with a median follow-up time of 4 years. In the bivariate analyses with only HAART use and time as covariates, HAART was associated with short-term improvements of 4 QOL domains: role functioning, social functioning, pain and perceived health index. After adjusting for demographic, socioeconomic, biological and clinical variables, HAART had small but significant short-term improvements on changes in summary QOL (mean change: 3.25; P = 0.02), role functioning (6.99; P < 0.01), social functioning (5.74; P < 0.01), cognitive functioning (3.59; P = 0.03), pain (6.73; P < 0.01), health perception (3.67; P = 0.03) and perceived health index (4.87; P < 0.01). These QOL scores typically remained stable or declined over additional follow-up and there was no indication that HAART modified these trends.ConclusionOur study demonstrated significant short-term HAART effects on most QOL domains, but additional use of HAART did not modify long-term trends. These changes could be attributed to the direct effect of HAART and indirect HAART effect mediated through clinical changes.

Linear regression with an independent variable subject to a detection limit.

Background: Linear regression with a left-censored independent variable X due to limit of detection (LOD) was recently considered by 2 groups of researchers: Richardson and Ciampi (Am J Epidemiol. 2003;157:355-363), and Schisterman et al (Am J Epidemiol. 2006;163:374-383). Methods: Both groups obtained consistent estimators for the regression slopes by replacing left-censored X with a constant, that is, the expectation of X given X below LOD E(X|X<LOD) in the former group and the sample mean of X given X above LOD in the latter. Results: Schisterman et al argued that their approach would be a better choice because the sample mean of X given X above LOD is available, whereas E(X|X<LOD) is unknown. Other substitution methods, such as replacing the left-censored values with LOD, or LOD/2,have been extensively used in the literature. Simulations were conducted to compare the performance under 2 scenarios in which the independent variable is normally and not normally distributed. Conclusion: Recommendations are given based on theoretical and simulation results. These recommendations are illustrated with one case study.

Disclosure of complementary and alternative medicine use to health care providers among HIV-infected women.

To determine prevalence and predictors of complementary and alternative medicine (CAM) use disclosure to health care providers and whether CAM use disclosure is associated with highly active antiretroviral therapy (HAART) adherence among HIV-infected women, we analyzed longitudinal data collected between October 1994 and March 2002 from HIV-infected CAM-using women enrolled in the Womens Interagency HIV Study. Repeated measures Poisson regression models were constructed to evaluate associations of selected predictors with CAM use disclosure and association between CAM use disclosure and HAART adherence. A total of 1,377 HIV-infected women reported CAM use during study follow-up and contributed a total of 4,689 CAM-using person visits. The overall prevalence of CAM use disclosure to health care providers was 36% across study visits. Women over 45 years old, with a college education, or with health insurance coverage were more likely to disclose their CAM use to health care providers, whereas women identified as non-Hispanic Black or other ethnicities were less likely to communicate their CAM usage. More health care provider visits, more CAM domains used, and higher health care satisfaction scores had significant relationships with increased levels of CAM use disclosure. Restricting analysis to use of herbal or nonherbal medications only, similar results were obtained. Compared to other CAM domains, mind-body practice had the lowest prevalence of CAM use disclosure. Additionally, CAM use disclosure was significantly associated with higher HAART adherence. From this study, we showed that a high percentage of HIV-infected women did not discuss their CAM use with health care providers. Interventions targeted towards both physicians and patients may enhance communication of CAM use, avoid potential adverse events and drug interactions, and enhance HAART adherence.

A Single-Nucleotide Polymorphism in CYP2B6 Leads to >3-Fold Increases in Efavirenz Concentrations in Plasma and Hair Among HIV-Infected Women

BACKGROUND Efavirenz exhibits marked interindividual variability in plasma levels and toxicities. Prior pharmacogenetic studies usually measure exposure via single plasma levels, examine limited numbers of polymorphisms, and rarely model multiple contributors. We analyzed numerous genetic and nongenetic factors impacting short-term and long-term exposure in a large heterogeneous population of human immunodeficiency virus (HIV)-infected women. METHODS We performed 24-hour intensive pharmacokinetic studies in 111 women receiving efavirenz under actual-use conditions and calculated the area-under-the-concentration-time curve (AUC) to assess short-term exposure; the efavirenz concentration in hair was measured to estimate long-term exposure. A total of 182 single-nucleotide polymorphisms (SNPs) and 45 haplotypes in 9 genes were analyzed in relationship to exposure by use of multivariate models that included a number of nongenetic factors. RESULTS Efavirenz AUCs increased 1.26-fold per doubling of the alanine aminotransferase level and 1.23-fold with orange and/or orange juice consumption. Individuals with the CYP2B6 516TT genotype displayed 3.5-fold increases in AUCs and 3.2-fold increases in hair concentrations, compared with individuals with the TG/GG genotype. Another SNP in CYP2B6 (983TT) and a p-glycoprotein haplotype affected AUCs without substantially altering long-term exposure. CONCLUSIONS This comprehensive pharmacogenomics study showed that individuals with the CYP2B6 516TT genotype displayed >3-fold increases in both short-term and long-term efavirenz exposure, signifying durable effects. Pharmacogenetic testing combined with monitoring of hair levels may improve efavirenz outcomes and reduce toxicities.

A C17T polymorphism in the mu opiate receptor is associated with quantitative measures of drug use in African American women

Previous studies of the association of the C17T polymorphism of the mu opiate receptor gene with substance dependence compared cases with substance dependence to controls and usually found no significant association. However, the studies were limited by small sample size—no study had more than 12 subjects with the TT genotype, a genotype that is rare in white and Asian subjects. Moreover, drug use is not dichotomous but follows a spectrum from non‐use to modest, intermittent use, to use several times daily. We asked whether the Kreek–McHugh–Schluger–Kellogg (KMSK) scales for alcohol, cocaine, opiates and tobacco that quantify substance use during the time of a subjects maximal use might be more sensitive measures than dichotomous outcomes. We administered the KMSK scales and completed C17T genotyping on 1009 human immunodeficiency virus (HIV)‐infected and 469 HIV‐uninfected women in The Womens Interagency HIV Study, an ongoing study of HIV in women. Forty‐two of the 697 African American, 1 of the 182 Hispanic and none of the 161 white women had the TT genotype. KMSK cocaine, alcohol and tobacco scores were significantly higher in the African American women with the TT genotype (P = 0.008, 0.0001, and 0.006, respectively), but opiate scores were not. Ordinal regression models controlling for HIV serostatus, age, education, and income had odds ratios for the TT genotype for predicting alcohol, tobacco, cocaine and opiates scores of 2.1 (P = 0.02), 2.4 (P = 0.0004), 2.0 (P = 0.03) and 1.9 (P = 0.07). We conclude that the TT genotype of OPRM1 may increase the risk of substance use and abuse.

Insomnia Symptoms and HIV Infection among Participants in the Women's Interagency HIV Study

OBJECTIVES This study assessed the prevalence of insomnia symptoms among women with and without HIV-infection and examined factors associated with insomnia. DESIGN Participants (n = 1682) were enrolled in the Womens Interagency HIV Study (WIHS); 69% were infected with HIV. This was a cross-sectional analysis of data from standardized interviewer-administered instruments and physical/gynecological exams. Analysis focused on sociodemographics, sleep measures, depressive symptoms, drug use, alcohol consumption, medications, and HIV-related clinical variables. Women were classified as having symptoms of insomnia if they reported either difficulty initiating sleep, difficulty maintaining sleep, or early morning awakening ≥ 3 times a week in the past 2 weeks. RESULTS Overall, HIV-infected women were 17% more likely to endorse insomnia symptoms than uninfected women (OR = 1.17, 95% CI: 1.04-1.34, P < 0.05). The adjusted prevalence of insomnia symptoms varied by HIV status and age groups. Among women ages 31-40 years, those with HIV infection were 26% more likely to endorse insomnia symptoms than their counterparts (OR = 1.26, 95% CI: 1.01-1.59, P < 0.05). No significant differences were observed in the likelihood of reporting insomnia symptoms based on HIV treatment type. Multivariate-adjusted regression analyses showed that depression was the most consistent and significant independent predictor of the likelihood of reporting insomnia symptoms across all age strata. CONCLUSIONS Insomnia symptoms are common among both HIV-infected and uninfected women. Prevalence of insomnia did not vary significantly by HIV status, except among younger women. Younger women with HIV infection are at greater risk for experiencing insomnia symptoms.

Underlying genetic structure impacts the association between CYP2B6 polymorphisms and response to efavirenz and nevirapine.

Objective:CYP2B6 variation predicts pharmacokinetic characteristics of its substrates. Consideration for underlying genetic structure is critical to protect against spurious associations with the highly polymorphic CYP2B6 gene. Design:The effect of CYP2B6 variation on response to its substrates, nonnucleoside reverse transcriptase inhibitors (NNRTIs), was explored in the Womens Interagency HIV Study. Methods:Five putative functional polymorphisms were tested for associations with virologic suppression within 1 year after NNRTI initiation in women naive to antiretroviral agents (n = 91). Principal components were generated to control for population substructure. Logistic regression was used to test the joint effect of rs3745274 and rs28399499, which together indicate slow, intermediate, and extensive metabolizers. Results:Rs3745274 was significantly associated with virologic suppression [odds ratio = 3.61, 95% confidence interval (CI) 1.16–11.22, P trend = 0.03]; the remaining polymorphisms tested were not significantly associated with response. Women classified as intermediate and slow metabolizers were 2.90 (95% CI 0.79–12.28) and 13.44 (95% CI 1.66 to infinity) times as likely to achieve virologic suppression compared to extensive metabolizers after adjustment for principal components (P trend = 0.005). Failure to control for genetic ancestry resulted in substantial confounding of the relationship between the metabolizer phenotype and treatment response. Conclusion:The CYP2B6 metabolizer phenotype was significantly associated with virologic response to NNRTIs; this relationship would have been masked by simple adjustment for self-reported ethnicity. Given the appreciable genetic heterogeneity that exists within self-reported ethnicity, these results exemplify the importance of characterizing underlying genetic structure in pharmacogenetic studies. Further follow-up of the CYP2B6 metabolizer phenotype is warranted, given the potential clinical importance of this finding.

Sexual Serosorting among Women with or at Risk of HIV Infection

Serosorting, the practice of selectively engaging in unprotected sex with partners of the same HIV serostatus, has been proposed as a strategy for reducing HIV transmission risk among men who have sex with men (MSM). However, there is a paucity of scientific evidence regarding whether women engage in serosorting. We analyzed longitudinal data on women’s sexual behavior with male partners collected in the Women’s Interagency HIV Study from 2001 to 2005. Serosorting was defined as an increasing trend of unprotected anal or vaginal sex (UAVI) within seroconcordant partnerships over time, more frequent UAVI within seroconcordant partnerships compared to non-concordant partnerships, or having UAVI only with seroconcordant partners. Repeated measures Poisson regression models were used to examine the associations between serostatus partnerships and UAVI among HIV-infected and HIV-uninfected women. The study sample consisted of 1,602 HIV-infected and 664 HIV-uninfected women. Over the follow-up period, the frequency of seroconcordant partnerships increased for HIV-uninfected women but the prevalence of UAVI within seroconcordant partnerships remained stable. UAVI was reported more frequently within HIV seroconcordant partnerships than among serodiscordant or unknown serostatus partnerships, regardless of the participant’s HIV status or types of partners. Among women with both HIV-infected and HIV-uninfected partners, 41% (63 HIV-infected and 9 HIV-uninfected) were having UAVI only with seroconcordant partners. Our analyses suggest that serosorting is occurring among both HIV-infected and HIV-uninfected women in this cohort.

The Effect of HAART on HIV RNA Trajectory Among Treatment Naïve Men and Women: a Segmental Bernoulli/Lognormal Random Effects Model with Left Censoring

Background: Highly active antiretroviral therapy (HAART) rapidly suppresses human immunodeficiency virus (HIV) viral replication and reduces circulating viral load, but the long-term effects of HAART on viral load remain unclear. Methods: We evaluated HIV viral load trajectories over 8 years following HAART initiation in the Multicenter AIDS Cohort Study and the Womens Interagency HIV Study. The study included 157 HIV-infected men and 199 HIV-infected women who were antiretroviral naive and contributed 1311 and 1837 semiannual person-visits post-HAART, respectively. To account for within-subject correlation and the high proportion of left-censored viral loads, we used a segmental Bernoulli/lognormal random effects model. Results: Approximately 3 months (0.30 years for men and 0.22 years for women) after HAART initiation, HIV viral loads were optimally suppressed (ie, with very low HIV RNA) for 44% (95% confidence interval = 39%–49%) of men and 43% (38%–47%) of women, whereas the other 56% of men and 57% of women had on average 2.1 (1.5–2.6) and 3.0 (2.7–3.2) log10 copies/mL, respectively. Conclusion: After 8 years on HAART, 75% of men and 80% of women had optimal suppression, whereas the rest of the men and women had suboptimal suppression with a median HIV RNA of 3.1 and 3.7 log10 copies/mL, respectively.

Effects of hepatitis C and HIV on cognition in women: data from the Women's Interagency HIV Study.

Objective:To compare neuropsychological scores in women infected with HIV, women infected with both HIV and hepatitis C, and uninfected subjects. Background:Some, but not all, studies have demonstrated that dual infection with Hepatitis C virus (HCV) and HIV has worse effects on cognition than infection with HIV alone. Design/Methods:The Womens Interagency HIV Study is an ongoing prospective study of the natural history of HIV in women where participants are reevaluated every 6 months. In a cross-sectional analysis, we evaluated the effects of active HIV and HCV infections on scores on symbol-digit modalities test, the Stroop interference test, and trails A and B after controlling for age, ethnicity, education, depression, liver disease, and current or past substance abuse. Results:Data were available for 1338 women—17.8 % had detectable hepatitis C virus and 67% were HIV seropositive. In fully adjusted general linear models, HCV viremia was not associated with scores on any of the cognitive tests. Conclusions:In this large sample of women, active HCV infection was not associated with scores on a small battery of neuropsychological tests.