Plasma HIV RNA levels have been associated with risk of human papillomavirus (HPV) and cervical neoplasia in HIV-seropositive women. However, little is known regarding local genital tract HIV RNA levels and their relation with cervical HPV and neoplasia.
In an HIV-seropositive women’s cohort with semi-annual follow-up, we conducted a nested case-control study of genital tract HIV RNA levels and their relation with incident high-grade squamous intraepithelial lesions sub-classified as severe (severe HSIL), as provided for under the Bethesda 2001 classification system. Specifically, 66 incident severe HSIL were matched to 130 controls by age, CD4+ count, HAART use, and other factors. We also studied HPV prevalence, incident detection, and persistence in a random sample of 250 subjects.
Risk of severe HSIL was associated with genital tract HIV RNA levels (odds ratio comparing HIV RNA ≥ the median among women with detectable levels versus undetectable [ORVL] 2.96; 95% CI: 0.99–8.84; Ptrend=0.03). However, this association became non-significant (Ptrend=0.51) following adjustment for plasma HIV RNA levels. There was also no association between genital tract HIV RNA levels and the prevalence of any HPV or oncogenic HPV. However, the incident detection of any HPV (Ptrend=0.02) and persistence of oncogenic HPV (Ptrend=0.04) were associated with genital tract HIV RNA levels, after controlling plasma HIV RNA levels.
These prospective data suggest that genital tract HIV RNA levels are not a significant independent risk factor for cervical pre-cancer in HIV-seropositive women, but leave open the possibility that they may modestly influence HPV infection, an early stage of cervical tumoriogenesis.
Genital tract HIV viral load; cervical neoplasia; HPV natural history
Previous studies suggest that indicators of central adiposity such as waist-to-hip ratio (WHR) and waist circumference may be altered by HIV infection, antiretroviral (ARV) treatment or both.
Waist and hip circumference and body mass index (BMI) were measured among participants of the Women’s Interagency HIV Study (WIHS) semiannually from 1999 to 2004. Generalized linear models evaluated longitudinal patterns of these measures and associations with demographic and clinical characteristics.
WHR was significantly larger while BMI, waist and hip circumference were significantly smaller at almost all eleven semiannual visits among 942 HIV-infected compared to 266 HIV-uninfected women. Among HIV-uninfected women, mean waist and hip circumference and BMI increased over the 5 year study period (waist: +4.1 cm or 4.4%, hip: +3.76 cm or 3.5% and BMI +2.43 kg/m2 or 8.2%), while WHR remained stable. Among the HIV-infected women, waist and hip circumference, BMI and WHR did not significantly change.
Independent predictors of smaller BMI among HIV-infected women included White race, HCV seropositivity, current smoking, higher viral load and lower CD4. Independent predictors of larger WHR among HIV-infected women included age, White and Other non-African-American race, higher CD4 and PI use. Use of a HAART regimen was not an independent predictor of either BMI or WHR..
HIV-infected women had higher WHR compared to HIV-uninfected women, despite lower BMI, waist and hip measurements. BMI, waist and hip circumference increased over 5 years among the HIV-uninfected women, but remained stable in the HIV-infected women. Among HIV-infected women, PI use was associated with larger WHR, although HAART use itself was not appreciably associated with either BMI or WHR.
anthropometrics; HIV; women; waist-to-hip ratio
The use of single-tablet ART regimens and its implications on adherence among HIV-infected women have not been well-described.
Participants were enrolled in the Women’s Interagency HIV Study (WIHS), a longitudinal study of HIV infection in U.S. women. We examined semiannual trends in single-tablet regimen use and ART adherence, defined as self-reported 95% adherence in the past 6 months, during 2006–2013. In a nested cohort study, we assessed the comparative effectiveness of a single-tablet versus a multiple-tablet regimen with respect to adherence, virologic suppression, quality of life, and AIDS-defining events, using propensity score matching to account for demographic, behavioral, and clinical confounders. We also examined these outcomes in a subset of women switching from a multiple- to single-tablet regimen, using a case-crossover design.
15,523 person-visits, representing 1,727 women (53% black, 29% Hispanic, 25% IDU, median age 47), were included. Use of single-tablet regimens among ART users increased from 7% in 2006 to 27% in 2013; adherence increased from 78% to 85% during the same period (both p<0.001). Single-tablet regimen use was significantly associated with increased adherence (adjusted RR 1.05, 95% CI 1.03–1.08) and virologic suppression (RR 1.06, 95% CI 1.01–1.11), while associations with improved quality of life and fewer AIDS-defining events did not achieve statistical significance. Similar findings were observed among the subset of switchers.
Single-tablet regimen use was associated with increased adherence and virologic suppression. Despite this, 15% of women prescribed ART were still not optimally adherent; additional interventions are needed to maximize therapeutic benefits.
adherence; antiretroviral therapy; HIV; time factors; United States; viral load; women
Individuals infected with human immunodeficiency virus type 1 (HIV) are more likely than non-infected individuals to develop depression. HIV lowers brain-derived neurotrophic factor (BDNF), a neurotrophic factor whose receptors play a crucial role in the pathophysiology of depression. Therefore, we examined whether a single-nucleotide polymorphism (SNP) in the BDNF gene (rs56164415) and related receptors TrkB (rs1212171) and p75NTR (rs2072446) were associated with depression in HIV infected individuals. 1365 HIV positive and 371 HIV negative female subjects were included. The distribution of alleles was analyzed independently in African-Americans (non-Hispanic) and Caucasians (non-Hispanic). We have found that the absence of depressive symptoms in HIV positive subjects is associated with a genetic variation of the TrkB but not BDNF or p75NTR genes. This mutation explains 0.8% and 4.4% of the variability for the absence of depression in African-Americans and Caucasians, respectively.
association studies; BDNF; HIV-1; p75NTR; rs1212171; rs2072446
Systemic and mucosal inflammation may play a role in HIV control. A cross-sectional comparison was conducted among women in the Women’s Interagency HIV Study (WIHS) to explore the hypothesis that compared to HIV-uninfected participants, women with HIV and in particular, those with high plasma viral load (PVL) have increased levels of mucosal and systemic inflammatory mediators and impaired mucosal endogenous antimicrobial activity.
19 HIV-uninfected, 40 HIV-infected on antiretroviral therapy (ART) with PVL ≤ 2600 copies/ml (low viral load) (HIV+-LVL), and 19 HIV-infected on or off ART with PVL >10,000 (high viral load) (HIV+-HVL) were evaluated. Immune mediators and viral RNA were quantified in plasma and cervicovaginal lavage (CVL). CVL antimicrobial activity was also determined.
Compared to HIV-uninfected, HIV+-HVL women had higher levels of mucosal, but not systemic pro-inflammatory cytokines and chemokines, higher Nugent scores, and lower E. coli bactericidal activity. In contrast, there were no significant differences between HIV+-LVL and HIV-uninfected controls. After adjusting for PVL, HIV genital tract shedding was significantly associated with higher CVL concentrations of IL-6, IL-1β, MIP-1α, and RANTES and higher plasma concentrations of MIP-1α. High PVL was associated with higher CVL levels of IL-1β and RANTES, as well as with higher Nugent scores, lower E. coli bactericidal activity, smoking and lower CD4 counts; smoking and CD4 count retained statistical significance in a multivariate model.
Further study is needed to determine if the relationship between mucosal inflammation and PVL is causal and to determine if reducing mucosal inflammation is beneficial.
HIV; HSV; mucosal immunity; inflammation; female genital tract; WIHS
HIV infection and illicit drug use are each associated with diminished cognitive performance. This study examined the separate and interactive effects of HIV and recent illicit drug use on verbal memory, processing speed and executive function in the multicenter Women's Interagency HIV Study (WIHS).
Participants included 952 HIV-infected and 443 HIV-uninfected women (mean age=42.8, 64% African-American). Outcome measures included the Hopkins Verbal Learning Test - Revised (HVLT-R) and the Stroop test. Three drug use groups were compared: recent illicit drug users (cocaine or heroin use in past 6 months, n=140), former users (lifetime cocaine or heroin use but not in past 6 months, n=651), and non-users (no lifetime use of cocaine or heroin, n=604).
The typical pattern of recent drug use was daily or weekly smoking of crack cocaine. HIV infection and recent illicit drug use were each associated with worse verbal learning and memory (p's<.05). Importantly, there was an interaction between HIV serostatus and recent illicit drug use such that recent illicit drug use (compared to non-use) negatively impacted verbal learning and memory only in HIV-infected women (p's <0.01). There was no interaction between HIV serostatus and illicit drug use on processing speed or executive function on the Stroop test.
The interaction between HIV serostatus and recent illicit drug use on verbal learning and memory suggests a potential synergistic neurotoxicity that may affect the neural circuitry underlying performance on these tasks.
Tenofovir has been associated with renal tubular injury. Biomarkers that signal early tubular dysfunction are needed because creatinine rise lags behind tenofovir-associated kidney dysfunction. We examined several urinary biomarkers to determine if rises accompanying tenofovir initiation preceded creatinine changes.
Three urinary biomarkers of tubular impairment- neutrophil gelatinase-associated lipocalin (NGAL), N-acetyl- β -D-glucosaminidase (NAG), and β-2-microglobulin (β2MG)-were measured across three time points (one pre-tenofovir visit and two post tenofovir visits) in one hundred and thirty two HIV-positive women from the Women's Interagency HIV Study (WIHS). Women initiating HAART containing tenofovir were propensity score matched to women initiating HAART without tenofovir and women not on HAART.
There were no differences between groups for NGAL or NAG but β2MG was 19 times more likely to be elevated among tenofovir users at the 2nd post tenofovir visit compared to non-TDF users at the pre-tenofovir visit (p<0.01). History of proteinuria was associated with elevated NGAL (p <0.01). Factors associated with elevated NAG were GFR<60 ml/min, history of proteinuria, hepatitis C (p<0.01 for all) and diabetes mellitus (p=0.05). Factors associated with increased odds of elevated β2MG were HIV RNA>100,000 copies/ml, hepatitis C, boosted protease inhibitor (PI) use, and GFR<60 ml/min (p≤0.01 for all).
β2MG levels are elevated in women on tenofovir indicating probable early renal dysfunction. Biomarker elevation is additionally associated with baseline chronic kidney disease, uncontrolled viremia, and boosted PI use. Future studies are needed to explore urinary biomarker thresholds in identifying treated HIV-infected individuals at risk for renal dysfunction.
Tenofovir; urinary biomarkers; HIV infected women
Coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) is common. HIV infection and treatment are associated with hypercoaguability; thrombosis in HCV is under-investigated. Proposed markers of hemostasis in HIV include higher D-dimer, Factor VIII% and Plasminogen Activator Inhibitor-1 (PAI-1Ag), and lower total Protein S% (TPS), but have not been examined in HCV. We assessed the independent association of HCV with these four measures of hemostasis in a multicenter, prospective study of HIV: the Women’s Interagency HIV Study (WIHS).
We randomly selected 450 HCV-infected (anti-HCV+ with detectable plasma HCV RNA) and 450 HCV-uninfected (anti-HCV−) women. HCV was the main exposure of interest in regression models.
443 HCV+ and 425 HCV− women were included. HCV+ women had higher Factor VIII% (124.4% ±3.9 vs. 101.8% ±3.7, p <0.001) and lower TPS (75.7% ±1.1 vs. 84.3% ±1.1, <0.001) than HCV−, independent of HIV infection and viral load; there was little difference in PAI-1Ag or log10 D-dimer. After adjustment for confounders, these inferences remained. HIV infection was independently associated with higher Factor VIII% and log10 D-dimer, and lower TPS.
HCV was independently associated with higher Factor VIII% and lower TPS consistent with hypercoaguability. Higher Factor VIII % and D-dimer and lower total Protein S % were also strongly associated with HIV infection and levels of HIV viremia, independent of HCV infection. Further investigation is needed to determine if there is increased thrombotic risk from HCV. Studies examining hemostasis markers in HIV infection must also assess the contribution of HCV infection.
HIV-infected persons have substantially higher risk of kidney failure than persons without HIV, but serum creatinine levels are insensitive for detecting declining kidney function. We hypothesized that urine markers of kidney injury would be associated with declining kidney function among HIV-infected women.
In the Women's Interagency HIV Study (WIHS), we measured concentrations of albumin-to-creatinine ratio (ACR), interleukin-18 (IL-18), kidney injury marker-1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) from stored urine among 908 HIV-infected and 289 uninfected participants. Primary analyses used cystatin C based estimated glomerular filtration rate (CKD-EPI eGFRcys) as the outcome, measured at baseline and two follow-up visits over eight years; secondary analyses used creatinine (CKD-EPI eGFRcr). Each urine biomarker was categorized into tertiles, and kidney decline was modeled with both continuous and dichotomized outcomes.
Compared with the lowest tertiles, the highest tertiles of ACR (−0.15ml/min/1.73m2, p<0.0001), IL-18 (−0.09ml/min/1.73m2, p<0.0001) and KIM-1 (−0.06ml/min/1.73m2, p<0.001) were independently associated with faster eGFRcys decline after multivariate adjustment including all three biomarkers among HIV-infected women. Among these biomarkers, only IL-18 was associated with each dichotomized eGFRcys outcome: ≥3% (Relative Risk 1.40; 95%CI 1.04-1.89); ≥5% (1.88; 1.30-2.71); and ≥10% (2.16; 1.20-3.88) for the highest versus lowest tertile. In alternative models using eGFRcr, the high tertile of KIM-1 had independent associations with 5% (1.71; 1.25-2.33) and 10% (1.78; 1.07-2.96) decline, and the high IL-18 tertile with 10% decline (1.97; 1.00-3.87).
Among HIV-infected women in the WIHS cohort, novel urine markers of kidney injury detect risk for subsequent declines in kidney function.
HIV; KIM-1; NGAL; IL-18; albumin-to-creatinine ratio; cystatin C; kidney injury
To evaluate the association between enrollment into an AIDS Drug Assistance Program (ADAP) and use of highly active antiretroviral therapy (HAART) and antihypertensive therapy.
Cross-sectional analyses of data were performed on HAART-eligible women enrolled in the California (n=439), Illinois (n=168), and New York (n=487) Women’s Interagency HIV Study (WIHS) sites. A subset of HIV-infected women with hypertension (n=395) was also analyzed. Unadjusted and adjusted backward stepwise elimination logistic regression measured the association between demographic, behavioral, and health service factors and non-use of HAART or antihypertensive medication.
In adjusted analysis of HAART non-use, women without ADAP were significantly more likely not to use HAART (odds ratio [OR] = 2.4, 95% confidence interval [CI] = 1.5–3.7) than women with ADAP. In adjusted analysis of antihypertensive medication non-use, women without ADAP had an increased but not significant odds of antihypertensive medication non-use (OR = 2.4, 95% CI = 0.93–6.0) than women with ADAP.
Government-funded programs for prescription drug coverage, such as ADAP, may play an important role in how HIV-positive women to access and use essential medications for chronic diseases.
AIDS; antiretroviral therapy; hypertension; women; healthcare disparity; prescription insurance
In the early highly active antiretroviral therapy (HAART) era, kidney dysfunction was strongly associated with death among HIV-infected individuals. We re-examined this association in the later HAART period to determine whether chronic kidney disease (CKD) remains a predictor of death after HAART-initiation.
To evaluate the effect of kidney function at the time of HAART initiation on time to all-cause mortality, we evaluated 1415 HIV-infected women initiating HAART in the Women’s Interagency HIV Study (WIHS). Multivariable proportional hazards models with survival times calculated from HAART initiation to death were constructed; participants were censored at the time of the last available visit or December 31, 2006.
CKD (eGFR <60 ml/min/1.73 m2) at HAART initiation was associated with higher mortality risk adjusting for age, race, hepatitis C serostatus, AIDS history and CD4+ cell count (hazard ratio [HR]=2.23, 95% confidence interval [CI]: 1.45–3.43). Adjustment for hypertension and diabetes history attenuated this association (HR=1.89, CI: 0.94–3.80). Lower kidney function at HAART initiation was weakly associated with increased mortality risk in women with prior AIDS (HR=1.09, CI: 1.00–1.19, per 20% decrease in eGFR).
Kidney function at HAART initiation remains an independent predictor of death in HIV-infected individuals, especially in those with a history of AIDS. Our study emphasizes the necessity of monitoring kidney function in this population. Additional studies are needed to determine mechanisms underlying the increased mortality risk associated with CKD in HIV-infected persons.
kidney disease; mortality; HIV; WIHS; antiretroviral therapy
Prevalence of microalbuminuria is increased in patients with HIV. Microalbuminuria is associated with increased mortality in other populations, including diabetics, for whom microalbuminuria testing is standard of care. We investigated whether microalbuminuria is associated with mortality in HIV-infected women not receiving antiretroviral therapy.
Urinalysis for proteinuria and semi-quantitative testing for microalbuminuria were performed in specimens from two consecutive visits in 1,547 HIV-infected women enrolled in the Women’s Interagency HIV Study in 1994–1995. Time to death was modeled using proportional hazards analysis.
Compared to women without albuminuria, the hazard ratio (HR) for all-cause mortality was increased in women with one (HR 3.4; 95% CI 2.2–5.2) or two specimens positive for either proteinuria or microalbuminuria (HR 3.9; 95% CI 2.1–7.0). The highest risk was observed in women with both specimens positive for proteinuria (HR 5.8; 95% CI 3.4–9.8). The association between albuminuria and all-cause mortality risk remained significant after adjustment for demographics, HIV disease severity, and related comorbidities. Similar results were obtained for AIDS death.
We identified a graded relationship between albuminuria and the risk of all-cause and AIDS mortality.
HIV; microalbuminuria; proteinuria; mortality
Sex-based differences in CD4 T-cell (CD4) counts are well recognized, but the basis for these differences has not been identified. Conceivably, homeostatic factors may play a role in this process by regulating T-cell maintenance and repletion. Interleukin (IL)-7 is essential for normal T-cell production and homeostasis. We hypothesized that differences in IL-7 might contribute to sex-based differences in CD4 counts. Circulating IL-7 levels were analyzed in 299 HIV-1–infected women and men. Regression analysis estimated that IL-7 levels were 40% higher in women than in men (P = 0.0032) after controlling for CD4 count, age, and race. Given the important role of IL-7 in T-cell development and homeostasis, these findings suggest that higher IL-7 levels may contribute to higher CD4 counts in women.
interleukin-7; sexual dimorphism; CD4-positive T cells; cytokines; sex differences
Opiate use is common in HIV- and hepatitis C virus (HCV)-infected individuals, however its contribution to the risk of diabetes mellitus is not well understood.
Prospective study of 1,713 HIV-infected and 652 uninfected participants from the Women’s Interagency HIV Study between October 2000 and March 2006. Diabetes defined as fasting glucose ≥126 mg/dl, or self-report of diabetes medication use or confirmed diabetes diagnosis. Opiate use determined using an interviewer-administered questionnaire. Detectable plasma HCV RNA confirmed HCV infection.
Current opiate users had a higher prevalence of diabetes (15%) than non-users (10%, p=.03), as well as a higher risk of incident diabetes (adjusted relative hazard [RHadj] 1.58, 95% CI 1.01, 2.46), after controlling for HCV infection, HIV/antiretroviral therapy status and diabetes risk factors including age, race/ethnicity, family history of diabetes and body mass index. HCV infection was also an independent risk factor for diabetes (RHadj 1.61, 95% CI 1.02, 2.52). HCV-infected women reporting current opiate use had the highest diabetes incidence (4.83 cases/100 person-years).
Among women with or at-risk for HIV, opiate use is associated with increased diabetes risk independently of HCV infection. Diabetic screening should be part of care for opiate users, and those infected with HCV.
opiate use; diabetes mellitus; fasting glucose; Hepatitis C virus; HIV; women
Low bone mineral density (BMD) has been reported in HIV + women, but less is known about the longitudinal evolution of BMD and fracture incidence.
In 100 HIV+ and 68 HIV− premenopausal women in the Women’s Interagency HIV Study (WIHS), BMD was measured by dual energy x-ray absorptiometry at the femoral neck (FN) and lumbar spine (LS) at index visit and after a median of 2.5 years.
In HIV+ women, BMD at index visit was normal but 5% lower at the LS and FN than in HIV− women. Annual percent decrease in BMD did not differ between HIV+ and HIV− women at the LS (−0.8±0.2% vs −0.4±0.2%, p=0.20) or FN (−0.8±0.3% vs −0.6±0.3%, p=0.56), and remained similar after adjustment for age, weight, and BMD at index visit. Among HIV+ women, bone loss was associated with vitamin D deficiency and opiate use but not with use or class of antiretrovirals. Incidence of self-reported fracture was 0.74/100 person-years in HIV+ women, and similar in HIV− women.
In premenopausal HIV+ women, index BMD was lower than comparable HIV− women; however, rates of bone loss at the LS and FN were similar over 2.5 years of observation, irrespective of ART.
The use of hormonal contraception (HC) is increasing in HIV-infected women. Both HC and HIV infection have been associated with adverse metabolic outcomes. We investigated the association of progestin-only and combined (estrogen/progestin) HC with disorders of glucose and lipid metabolism in HIV-infected and uninfected women.
Linear mixed models evaluated the association of HC type with fasting HDL, LDL, triglycerides, the homeostasis model assessment estimate of insulin resistance (HOMA-IR), and glucose in 885 HIV-infected and 408 HIV-uninfected women from the Women's Interagency HIV Study seen between October 2000 and September 2005.
Compared to non-HC users, progestin-only HC was independently associated with lower HDL (-3mg/dL;95% confidence interval[CI]:-5,-1 in HIV-infected and -6mg/dL;95% CI:-9,-3 in HIV-uninfected women), greater HOMA (+0.86;95% CI:0.51,1.22 and +0.56;95% CI:0.12,1.01). Combined HC was associated with higher HDL(+5mg/dL;95% CI:2,7 and +5mg/dL;95% CI:3,7).
Progestin–only HC is associated with lower HDL and greater HOMA-IR than non-HC users. Combined HC may be preferred in HIV-infected women of reproductive age at risk for cardiovascular disease, but interactions with antiretroviral therapy that may impair contraceptive efficacy have been reported. Alternative HC methods that minimize adverse outcomes but maintain efficacy require further study.
HIV/AIDS; hormonal contraception; Depo Provera®; HDL; triglycerides
To assess trends in mortality and cause of death for women with HIV, we studied deaths over a 10 year period among participants in the Women’s Interagency HIV Study (WIHS), a representative US cohort.
Deaths were ascertained by National Death Index-Plus match and causes of death determined by death certificate.
From 1995 through 2004, 710 of 2792 HIV-infected participants died. During this interval the standardized mortality ratio (SMR) fell from a high of 24.7 in 1996 to a plateau with a mean of 10.3 from 2001–2004. Over the decade, deaths from non-AIDs causes increased and accounted for the majority of deaths by 2001–2004. The most common non-AIDS causes of death were trauma or overdose, liver disease, cardiovascular disease and malignancy. Independent predictors of mortality besides HIV-associated variables were depressive symptoms, and active hepatitis B or C. Women who were overweight or obese were significantly less likely to die of AIDS than women of normal weight.
In the WIHS, the death rate has plateaued in recent years. While HIV-associated factors predicted AIDS and non-AIDS deaths, other treatable conditions predicted mortality. Further gains in reducing mortality among HIV-infected women may require broader access to therapies for depression, viral hepatitis and HIV itself.
HIV; mortality; women; viral hepatitis; non-AIDs mortality
The effects of HIV serostatus and combination antiretroviral therapy (cART) on plasma homocysteine (Hcy) are uncertain.
Plasma Hcy was assayed in a cross-sectional study of 249 HIV-infected and 127 HIV-uninfected women at the Bronx Women’s Interagency HIV Study site.
Mean plasma Hcy was 7.42 ± 2.68 in HIV-infected and 7.18 ± 2.66 µmol/L in HIV-uninfected women (P = 0.40). Hyperhomocysteinemia (defined as Hcy > 10 µmol/L) was seen in 16.9% and 13.4 % of HIV-infected and HIV-uninfected women, respectively (P=0.45). Among HIV-infected women, cART use was not associated with Hcy level. Compared to the lowest quartile, women with Hcy in the highest quartile had lower mean serum vitamin B12 and RBC folate levels. In multivariate analysis that did not include micronutrient levels, age, serum creatinine and lower CD4% were significantly associated with plasma Hcy level in HIV-infected women.
Plasma Hcy was not associated with HIV serostatus or use of cART in this cross-sectional study. Reduced availability of folate cofactors for Hcy remethylation in HIV-infected women with lower folate intake and decreased health status may influence Hcy levels.
Homocysteine; HIV; women; vitamin B12; folate
Small intensive pharmacokinetic (PK) studies of medications in early-phase trials cannot identify the range of factors that influence drug exposure in heterogeneous populations. We performed PK studies in large numbers of HIV-infected women on nonnucleoside-reverse-transcriptase-inhibitors (NNRTIs) under conditions of actual use to assess patient characteristics that influence exposure and evaluated the relationship between exposure and response.
225 women on NNRTI-based antiretroviral regimens from the Women’s Interagency HIV Study (WIHS) were enrolled into 12 or 24-hour PK studies. Extensive demographic, laboratory and medication covariate data was collected before and during the visit to be used in multivariate models. Total NNRTI drug exposure was estimated by area-under-the-concentration-time curves (AUC).
Hepatic inflammation and renal insufficiency were independently associated with increased nevirapine (NVP) exposure in multivariate analyses; crack cocaine, high fat diets, and amenorrhea were associated with decreased levels (n=106). Higher efavirenz (EFV) exposure was seen with increased transaminase, albumin levels, and orange juice consumption; tenofovir use, increased weight, being African-American and amenorrhea were associated with decreased exposure (n=119). With every 10-fold increase in NVP or EFV exposure, participants were 3.3 and 3.6 times as likely to exhibit virologic suppression, respectively. Patients with higher drug exposure were also more likely to report side effects on therapy.
Our study identifies and quantitates previously unrecognized factors modifying NNRTI exposure in the “real-world” setting. Comprehensive PK studies in representative populations are feasible and may ultimatley lead to dose optimization strategies in patients at risk for failure or adverse events.
HIV; antiretrovirals; nevirapine; efavirenz; pharmacokinetics; drug exposure; women