Peter F. Rebeiro

Race and Sex Differences in Antiretroviral Therapy Use and Mortality among HIV-Infected Persons in Care

BACKGROUND There are conflicting data regarding race, sex, and mortality among persons infected with human immunodeficiency virus (HIV). We studied all-cause mortality among persons in care during the highly-active antiretroviral therapy (HAART) era. METHODS This retrospective cohort study included patients who made>or=1 clinic visit from January 1998 through December 2005. RESULTS Of 2605 patients (with 6657 person-years of follow-up), 38% were black and 24% were female. The percentage of time in care while receiving HAART was lower for blacks than for nonblacks (47% vs. 76%; P<.001) and for females than for males (57% vs. 71%; P=.01). There were 253 deaths (38 per 1000 person-years). After adjustment for characteristics at baseline, death was associated with black race (hazard ratio [HR], 1.33; P .04), female sex (HR, 1.53; P .007), injection drug use (IDU) as a risk factor for HIV infection (HR, 1.61; P .009), older age (HR, 1.45 per 10 years; P<.001), a lower CD4 cell count (HR, 0.59 for 200 vs. 350 cells/mm3; P<.001) and a higher HIV type 1 RNA level (HR, 1.35; P<.001). After adjustment for the length of time that HAART was received, black race (HR, 1.00; P .99) and IDU (HR, 1.37; P .09) were no longer associated with death, but female sex was (HR, 1.62; P=.002). CONCLUSIONS Race-associated differences in mortality likely resulted from HAART use. Women had an increased risk of death even after adjustment for HAART use. Addressing racial disparities will require improved HAART utilization. Increased mortality among women requires further study.

Drug Transporter and Metabolizing Enzyme Gene Variants and Nonnucleoside Reverse-Transcriptase Inhibitor Hepatotoxicity

This nested case-control study examined relationships between MDR1, CYP2B6, and CYP3A4 variants and hepatotoxicity during antiretroviral therapy with either efavirenz- or nevirapine-containing regimens. Decreased risk of hepatotoxicity was associated with MDR1 3435C-->T (odds ratio, 0.254; P=.021). An interaction between MDR1 and hepatitis B surface antigen status predicted risk with 82% accuracy (P<.001).

Oxidant Stress Is Increased during Treatment of Human Immunodeficiency Virus Infection

Some diseases and environmental exposures, including those that are risk factors for atherosclerosis, are associated with increased oxidant stress. The objective of this cross-sectional, observational study was to determine whether oxidant stress is increased during human immunodeficiency virus type 1 (HIV-1) infection or its therapy. To quantify oxidant stress, plasma F2 isoprostane (F2-IsoP) concentrations were determined by gas chromatography/mass spectroscopy. A total of 120 subjects were enrolled during routine primary care visits. The median CD4+ T cell count was 341 cells/mm3, the median HIV-1 RNA level was 3.4 log10 copies/mL, and 74% of patients were receiving antiretroviral therapy. Plasma F2-IsoP concentrations were 12-149 pg/mL (median, 31 pg/mL). In univariate analysis, higher F2-IsoP concentrations were associated with lower log10 plasma HIV-1 RNA levels (P=.009) and with efavirenz use (P=.02). Both factors remained associated with plasma F2-IsoP concentrations in multivariate analysis. Oxidant stress associated with therapeutic control of viral replication may have important implications for long-term complications of antiretroviral therapy.

Pregnancy and HIV Disease Progression during the Era of Highly Active Antiretroviral Therapy

BACKGROUND Before the availability of highly active antiretroviral therapy (HAART), there was no clear effect of pregnancy on human immunodeficiency virus (HIV) disease progression. This has not been assessed during the HAART era. METHODS We conducted an observational cohort study among HIV-infected women with >or=1 outpatient clinic visit between January 1997 and December 2004. HIV disease progression was defined as the occurrence of an AIDS-defining event or death. RESULTS Of 759 women who met the inclusion criteria, 139 (18%) had had >1 pregnancy, and 540 (71%) had received HAART. There was no difference in HAART duration by pregnancy status. Eleven pregnant (8%) and 149 nonpregnant (24%) women progressed to AIDS or death. After controlling for age, baseline CD4(+) lymphocyte count, baseline HIV-1 RNA level, and durable virologic suppression in a Cox proportional hazards model that included propensity score for pregnancy, pregnancy was associated with a decreased risk of disease progression (hazard ratio [HR], 0.40 [95% confidence interval {CI}, 0.20-0.79]; P=.009]). In a matched-pair analysis of 81 pregnant women matched to 81 nonpregnant women according to age, baseline CD4(+) lymphocyte count, receipt of HAART, and date of cohort entry, pregnant women had a lower risk of disease progression both before (HR, 0.10 [95% CI, 0.01-0.89]; P=.04) and after (HR, 0.44 [95% CI, 0.19-1.00]; P=.05) the pregnancy event. CONCLUSION Pregnancy was associated with a lower risk of HIV disease progression in this HAART-era study. This finding could be the result of the healthier immune status of women who become pregnant or could possibly be related to a beneficial interaction between pregnancy and HAART.

End-Stage Renal Disease Among HIV-Infected Adults in North America

BACKGROUND Human immunodeficiency virus (HIV)-infected adults, particularly those of black race, are at high-risk for end-stage renal disease (ESRD), but contributing factors are evolving. We hypothesized that improvements in HIV treatment have led to declines in risk of ESRD, particularly among HIV-infected blacks. METHODS Using data from the North American AIDS Cohort Collaboration for Research and Design from January 2000 to December 2009, we validated 286 incident ESRD cases using abstracted medical evidence of dialysis (lasting >6 months) or renal transplant. A total of 38 354 HIV-infected adults aged 18-80 years contributed 159 825 person-years (PYs). Age- and sex-standardized incidence ratios (SIRs) were estimated by race. Poisson regression was used to identify predictors of ESRD. RESULTS HIV-infected ESRD cases were more likely to be of black race, have diabetes mellitus or hypertension, inject drugs, and/or have a prior AIDS-defining illness. The overall SIR was 3.2 (95% confidence interval [CI], 2.8-3.6) but was significantly higher among black patients (4.5 [95% CI, 3.9-5.2]). ESRD incidence declined from 532 to 303 per 100 000 PYs and 138 to 34 per 100 000 PYs over the time period for blacks and nonblacks, respectively, coincident with notable increases in both the prevalence of viral suppression and the prevalence of ESRD risk factors including diabetes mellitus, hypertension, and hepatitis C virus coinfection. CONCLUSIONS The risk of ESRD remains high among HIV-infected individuals in care but is declining with improvements in virologic suppression. HIV-infected black persons continue to comprise the majority of cases, as a result of higher viral loads, comorbidities, and genetic susceptibility.

Disparities in the Quality of HIV Care When Using US Department of Health and Human Services Indicators

We estimated US Department of Health and Human Services (DHHS)-approved human immunodeficiency virus (HIV) indicators. Among patients, 71% were retained in care, 82% were prescribed treatment, and 78% had HIV RNA ≤200 copies/mL; younger adults, women, blacks, and injection drug users had poorer outcomes. Interventions are needed to reduce retention- and treatment-related disparities.

CD4 Lymphocyte Percentage Predicts Disease Progression in HIV-Infected Patients Initiating Highly Active Antiretroviral Therapy with CD4 Lymphocyte Counts >350 Lymphocytes/mm3

BACKGROUND The optimal timing of highly active antiretroviral therapy (HAART) in human immunodeficiency virus (HIV)-infected patients with > or = 200 absolute CD4 lymphocytes/mm3 is unknown. CD4 lymphocyte percentage could add prognostic information. METHODS Persons who initiated HAART between 1 January 1998 and 1 January 2003, received > or = 30 days of therapy, and had baseline CD4 lymphocyte data available were included in the study. The log-rank test for time to event and Cox proportional hazards models were used to determine predictors of a new acquired immunodeficiency syndrome-defining illness or death. RESULTS A total of 788 patients met the inclusion criteria. At baseline, subjects had a median of 225 CD4 lymphocytes/mm3 and 17% CD4 lymphocytes. Subjects with < 17% CD4 lymphocytes had earlier disease progression, compared with subjects with > or = 17%, both in the entire cohort (P<.0001) and of those subjects with > 350 absolute CD4 lymphocytes/mm3 at baseline (P=.03). CD4 lymphocyte percentage < 17% was the strongest predictor of disease progression among subjects in this latter group (hazard ratio, 3.57; P=.045). CONCLUSIONS In this cohort, CD4 lymphocyte percentage predicted disease progression in HIV-infected subjects who initiated therapy with > 350 CD4 lymphocytes/mm3. This information may help identify persons who will derive the greatest benefit from initiation of HAART.

Impact of age on retention in care and viral suppression

Background:Retention in care is important for all HIV-infected persons and is strongly associated with initiation of antiretroviral therapy and viral suppression. However, it is unclear how retention in care and age interact to affect viral suppression. We evaluated whether the association between retention and viral suppression differed by age at entry into care. Methods:Cross-sectional analysis (2006–2010) involving 17,044 HIV-infected adults in 14 clinical cohorts across the United States and Canada. Patients contributed 1 year of data during their first full-calendar year of clinical observation. Poisson regression examined associations between retention measures [US National HIV/AIDS Strategy (NHAS), US Department of Health and Human Services (DHHS), 6-month gap, and 3-month visit constancy] and viral suppression (HIV RNA ⩽200 copies/mL) by age group: 18–29 years, 30–39 years, 40–49 years, 50–59 years, and 60 years or older. Results:Overall, 89% of patients were retained in care using the NHAS measure, 74% with the DHHS indicator, 85% did not have a 6-month gap, and 62% had visits in 3–4 quarters of the year; 54% achieved viral suppression. For each retention measure, the association with viral suppression was significant for only the younger age groups (18–29 and 30–39 years): 18–29 years [adjusted prevalence ratio (APR) = 1.33, 95% confidence interval (CI): 1.03 to 1.70]; 30–39 years (APR = 1.23, 95% CI: 1.01 to 1.49); 40–49 years (APR = 1.06, 95% CI: 0.90 to 1.22); 50–59 (APR = 0.92, 95% CI: 0.75 to 1.13); ≥60 years (APR = 0.99, 95% CI: 0.63 to 1.56) using the NHAS measure as a representative example. Conclusions:These results have important implications for improving viral control among younger adults, emphasizing the crucial role retention in care plays in supporting viral suppression in this population.

Non-AIDS-defining events among HIV-1-infected adults receiving combination antiretroviral therapy in resource-replete versus resource-limited urban setting

Objective:To compare incidence and distribution of non-AIDS-defining events (NADEs) among HIV-1-infected adults receiving combination antiretroviral therapy (cART) in urban sub-Saharan African versus United States settings. Design:Retrospective cohort analysis of clinical trial and observational data. Methods:Compared crude and standardized (to US cohort by age and sex) NADE rates from two urban adult HIV-infected cART-initiating populations: a clinical trial cohort in Gaborone, Botswana (Botswana) and an observational cohort in Nashville, Tennessee (USA). Results:Crude NADE incidence rates were similar: 10.0 [95% confidence interval 6.3–15.9] per 1000 person-years in Botswana versus 12.4 [8.4–18.4] per 1000 person-years in the United States. However, after standardizing to an older, predominantly male US population, the overall NADE incidence rates were higher in Botswana [18.7 (8.3–33.1) per 1000 person-years]. Standardized rates differed most for cardiovascular events (8.4 versus 5.0 per 1000 person-years) and non-AIDS-defining malignancies (8.0 versus 0.5 per 1000 person-years) – both higher in Botswana. Conversely, hepatic NADE rates were higher in the United States (4.0 versus 0.0 per 1000 person-years), whereas renal NADE rates [3.0 per 1000 person-years (United States) versus 2.4 per 1000 person-years (Botswana)] were comparable. Conclusion:Crude NADE incidence rates were similar between cART-treated patients in a US observational cohort and a sub-Saharan African clinical trial. However, when standardized to the US cohort, overall NADE rates were higher in Botswana. NADEs appear to be a significant problem in our sub-Saharan African setting, and the monitoring, prevention, and treatment of NADEs should be a critical component of care in resource-limited settings.

Drug Use and Receipt of Highly Active Antiretroviral Therapy among HIV-Infected Persons in Two U.S. Clinic Cohorts

Objective Drug use and receipt of highly active antiretroviral therapy (HAART) were assessed in HIV-infected persons from the Comprehensive Care Center (CCC; Nashville, TN) and Johns Hopkins University HIV Clinic (JHU; Baltimore, MD) between 1999 and 2005. Methods Participants with and without injection drug use (IDU) history in the CCC and JHU cohorts were evaluated. Additional analysis of persons with history of IDU, non-injection drug use (NIDU), and no drug use from CCC were performed. Activity of IDU and NIDU also was assessed for the CCC cohort. HAART use and time on HAART were analyzed according to drug use category and site of care. Results 1745 persons were included from CCC: 268 (15%) with IDU history and 796 (46%) with NIDU history. 1977 persons were included from JHU: 731 (35%) with IDU history. Overall, the cohorts differed in IDU risk factor rates, age, race, sex, and time in follow-up. In multivariate analyses, IDU was associated with decreased HAART receipt overall (OR = 0.61, 95% CI: [0.45–0.84] and OR = 0.58, 95% CI: [0.46–0.73], respectively for CCC and JHU) and less time on HAART at JHU (0.70, [0.55–0.88]), but not statistically associated with time on HAART at CCC (0.78, [0.56–1.09]). NIDU was independently associated with decreased HAART receipt (0.62, [0.47–0.81]) and less time on HAART (0.66, [0.52–0.85]) at CCC. These associations were not altered significantly whether patients at CCC were categorized according to historical drug use or drug use during the study period. Conclusions Persons with IDU history from both clinic populations were less likely to receive HAART and tended to have less cumulative time on HAART. Effects of NIDU were similar to IDU at CCC. NIDU without IDU is an important contributor to HAART utilization.