Cystatin C could improve chronic kidney disease (CKD) classification in HIV-infected women relative to serum creatinine.
Retrospective cohort analysis.
Cystatin C and creatinine were measured from specimens taken and stored during the 1999–2000 exam among 908 HIV-infected participants in the Women’s Interagency HIV study (WIHS). Mean follow-up was 10.2 years. The associations of baseline categories (<60, 60–90, and >90 mL/min/1.73m2) of creatinine eGFR (eGFRcr), cystatin C eGFR (eGFRcys), and combined creatinine-cystatin C eGFR (eGFRcr-cys) with all-cause mortality were evaluated using multivariable Cox regression. The net reclassification index (NRI) was calculated to evaluate the effect of cystatin C on reclassification of CKD staging.
The prevalence of CKD (eGFR<60) at baseline was higher with eGFRcys (10.1%) compared to eGFRcr (6.7%, p=0.0006) and eGFRcr-cys (7.5%, p=0.011). Relative to eGFR >90, the eGFR <60 category by eGFRcys (Adjusted HR: 2.56; 95% CI: 1.63, 4.02), eGFRcr-cys (3.11; 1.94–5.00), and eGFRcr (2.34; 1.44–3.79) was associated with increased mortality risk. However, the eGFR 60–90 category was associated with increased mortality risk for eGFRcys (1.80; 1.28–2.53) and eGFRcr-cys (1.91; 1.38–2.66) but not eGFRcr (1.20; 0.85–1.67). The overall NRI for mortality was 26% when reclassifying from eGFRcr to eGFRcys (p<0.001) and was 20% when reclassifying from eGFRcr to eGFRcr-cys (p<0.001).
Cystatin C detected a higher prevalence of CKD relative to creatinine and improves CKD staging relative to creatinine by reclassifying individuals at the highest mortality risk to lower eGFR categories.
Creatinine; Cystatin C; Glomerular Filtration Rate; HIV; Mortality; Kidney; Women
HIV; pulmonary hypertension; Doppler echocardiography; right heart catheterization
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 determine whether intensification with raltegravir improves endothelial function in antiretroviral-treated, HIV-infected individuals.
Randomized, double-blinded, placebo-controlled study.
Fifty-six subjects with treatment-mediated viral suppression for at least one year were randomized to add raltegravir 400 mg twice daily or matching placebo for 24 weeks. The primary endpoint was the difference in rate of change in endothelial function (as assessed by flow-mediated vasodilation of the brachial artery [FMD]) from baseline to week 24 between the raltegravir and placebo groups. Linear mixed models were used to evaluate the association of treatment group with changes in FMD, immune activation, and measures of viral persistence.
At baseline, the median CD4+ T cell count was 498 cells/mm3, nadir CD4+ T cell count was 191 cells/mm3, duration of HIV infection was 18 years, FMD was 3.3%, and hyperemic velocity (a marker of microvascular function) was 68.3 cm. There were no significant differences between treatment groups in rate of change in FMD (raltegravir group +0.032% per week, placebo group +0.023% per week; p=0.60). There were also no differences between treatment groups in rate of change in hyperemic velocity, immune activation, or viral persistence. In multivariable analysis, older age, longer duration of HIV infection, and current abacavir use were associated with lower FMD. Lower CD4+ T cell count and current abacavir use were associated with lower hyperemic velocity.
The addition of raltegravir to suppressive antiretroviral therapy did not have a significant impact on cardiovascular risk, as assessed by endothelial function (ClinicalTrials.gov NCT00843713).
HIV; raltegravir intensification; endothelial function; flow-mediated vasodilation
Weight gain has been described in Parkinson’s disease (PD) patients after subthalamic nucleus (STN) deep brain stimulation (DBS).
We examined change in weight following DBS in both PD and dystonia patients to further investigate the role of disease and brain target (STN or GPi) specificity.
Data was retrospectively collected on 61 PD DBS patients (STN (n=31) or GPi (n=30)) and on 36 dystonia DBS patients (STN (n=9) and GPi (n=27)) before and after surgery. Annual change in body mass index (BMI) was evaluated with non-parametric tests between groups and multiple quantile regression.
PD patients treated with STN DBS had a small increase in median BMI while those with GPi had a small decrease in BMI. Dystonia patients treated with STN DBS had a greater increase in BMI per year compared to those treated with GPi. Multivariable regression analyses for each disease showed little difference between targets in weight gain in those with PD, but STN target was strongly associated with weight gain in dystonia patients (STN vs. GPi, +7.99 kg, p=0.012).
Our results support previous reports of weight gain after DBS in PD. This is the first report to suggest a target-specific increase in weight following STN DBS in dystonia patients.
deep brain stimulation; Parkinson’s disease; dystonia; Subthalamic Nucleus; Globus Pallidus; weight change
Despite widespread highly active antiretroviral therapy use, HIV disease remains associated with increased risk of kidney disease. Whether tenofovir use is associated with higher risk of kidney disease is controversial.
We evaluated the association of cumulative and ever exposure to tenofovir on kidney outcomes in 10,841 HIV-infected patients from the Veterans Health Administration who initiated antiretroviral therapy from 1997-2007.
Cox proportional hazards and marginal structural models evaluated associations between tenofovir and time to first occurrence of 1) proteinuria (two consecutive urine dipstick measurements ≥30mg/dL), 2) rapid decline in kidney function (≥3ml/min/1.73m2 annual decline), and 3) CKD (estimated glomerular filtration rate <60ml/min/1.73m2).
Median follow-up ranged from 3.9 years (proteinuria) to 5.5 years (CKD), during which 3400 proteinuria, 3078 rapid decline, and 533 CKD events occurred. After multivariable adjustment, each year of exposure to tenofovir was associated with 34% increased risk of proteinuria (95%CI 25-45%, p<0.0001), 11% increased risk of rapid decline (3-18%, p=0.0033), and 33% increased risk of CKD (18-51%; p<0.0001). Pre-existing renal risk factors did not appear to worsen the effects of tenofovir. Other ARVs showed weaker or inconsistent associations with kidney disease events. Among those who discontinued tenofovir use, risk of kidney disease events did not appear to decrease during follow-up.
Tenofovir exposure was independently associated with increased risk for three types of kidney disease events, and did not appear to be reversible. Because subtle kidney function decline affects long-term morbidity and mortality, the balance between efficacy and probable adverse effects requires further study.
HIV; antiretroviral therapy; kidney disease; tenofovir
Intermuscular adipose tissue (IMAT) is associated with metabolic abnormalities similar to those associated with visceral adipose tissue (VAT). Increased IMAT has been found in obese human immunodeficiency virus (HIV)-infected women. We hypothesized that IMAT, like VAT, would be similar or increased in HIV-infected persons compared with healthy controls, despite decreases in subcutaneous adipose tissue (SAT) found in HIV infection. In the second FRAM (Study of Fat Redistribution and Metabolic Change in HIV infection) exam, we studied 425 HIV-infected subjects and 211 controls (from the Coronary Artery Risk Development in Young Adults study) who had regional AT and skeletal muscle (SM) measured by magnetic resonance imaging (MRI). Multivariable linear regression identified factors associated with IMAT and its association with metabolites. Total IMAT was 51% lower in HIV-infected participants compared with controls (P = 0.003). The HIV effect was attenuated after multivariable adjustment (to −28%, P < 0.0001 in men and −3.6%, P = 0.70 in women). Higher quantities of leg SAT, upper-trunk SAT, and VAT were associated with higher IMAT in HIV-infected participants, with weaker associations in controls. Stavudine use was associated with lower IMAT and SAT, but showed little relationship with VAT. In multivariable analyses, regional IMAT was associated with insulin resistance and triglycerides (TGs). Contrary to expectation, IMAT is not increased in HIV infection; after controlling for demographics, lifestyle, VAT, SAT, and SM, HIV+ men have lower IMAT compared with controls, whereas values for women are similar. Stavudine exposure is associated with both decreased IMAT and SAT, suggesting that IMAT shares cellular origins with SAT.
To evaluate the effect of HIV infection on longitudinal changes in kidney function and to identify independent predictors of kidney function changes in HIV-infected individuals.
A prospective cohort.
Cystatin C was measured at baseline and at the 5-year follow-up visit of the Study of Fat Redistribution and Metabolic Change in HIV infection in 554 HIV-infected participants and 230 controls. Control participants were obtained from the Coronary Artery Risk Development in Young Adults study. Glomerular filtration rate (eGFRcys) was estimated using the formula 76.7 × cysC−1.19.
Compared with controls, HIV-infected participants had a greater proportion of clinical decliners (annual decrease in eGFRcys > 3 ml/min per 1.73 m2; 18 versus 13%, P=0.002) and clinical improvers (annual increase in eGFRcys > 3 ml/min per 1.73 m2; 26 versus 6%, P< 0.0001). After multivariable adjustment, HIV infection was associated with higher odds of both clinical decline (odds ratio 2.2; 95% confidence interval 1.3, 3.9, P = 0.004) and clinical improvement (odds ratio 7.3; 95% confidence interval 3.9, 13.6, P ≤ 0.0001). Among HIV-infected participants, a decrease in HIV viral load during follow-up was independently associated with clinical improvement; conversely, higher baseline and an increase in viral load during follow-up were associated with clinical decline. No individual antiretroviral drug or drug class appeared to be substantially associated with clinical decline or improvement.
Compared with controls, HIV-infected persons were more likely both to have clinical decline and clinical improvement in kidney function during 5 years of follow-up. The extent of viremic control had a strong association with longitudinal changes in kidney function.
cystatin C; glomerular filtration rate; HIV; kidney; viral load
HIV infection is associated with decreased thrombin generation and an increased antithrombin level. These data suggest that HIV infection may not be associated with an increased propensity towards clotting.
Background. Excess risk of cardiovascular disease occurs in effectively treated individuals with human immunodeficiency virus (HIV) infection. Although elevated plasma D-dimer levels are associated with increased morbidity and mortality, the impact of HIV infection on coagulation in vivo has not been well studied.
Methods. We measured D-dimers, antithrombin, endogenous thrombin potential (ETP; a functional measure of thrombin generation in vitro), thrombin/antithrombin complexes (TAT; a measure of thrombin generation in vivo), tissue factor, prothrombin fragment 1 + 2 (F1+2), and normalized APC sensitivity ratio (nAPCsr) in 199 HIV-positive men who were receiving antiretroviral therapy and had an undetectable HIV RNA level, in 79 HIV-positive untreated men, and in 39 uninfected controls.
Results. Median antithrombin levels were higher while the ETP was lower among HIV-infected adults (treated and untreated), compared with controls. There were few differences between coagulation markers in the 2 HIV groups. Compared with controls, the nAPCsr was lower in treated men and the TAT level was lower in untreated individuals. We observed little difference among measured levels of D-dimer, tissue factor, or F1+2 between HIV-infected individuals and controls. Antiretroviral therapy exposure was associated with a lower antithrombin level, a lower nAPCsr, and a lower ETP, while history of opportunistic infection was associated with a higher nAPCsr.
Conclusions. HIV infection is associated with decreased thrombin generation, as measured by the ETP, and an increased antithrombin level. These data suggest that HIV infection may not be associated with increased propensity toward clotting, as has been suggested on the basis of isolated measures of D-dimer levels.
Genetic studies may help explain abnormalities of fat distribution in HIV-infected patients treated with antiretroviral therapy (ARV).
Subcutaneous adipose tissue (SAT) volume measured by magnetic resonance imaging (MRI) in leg, lower trunk, upper trunk, and arm was examined in 192 HIV-infected Caucasian men, ARV-treated from the Fat Redistribution and Metabolic Change in HIV infection (FRAM) study. Single nucleotide polymorphisms (SNPs) were assayed using the Illumina HumanCNV370-quad beadchip. Multivariate and univariate genome wide association analyses of the four SAT depots were implemented in PLINK software adjusted for age and ARV duration. Functional annotation analysis (FAA) using Ingenuity Systems Pathway Analysis tool (IPA) was carried out for markers with P<10-3 near known genes identified by multivariate analysis.
Loci (rs10504906, rs13267998, rs921231) in or near the anion exchanger solute carrier family 26, member 7 isoform a (SLC26A7) were strongly associated with upper trunk and arm SAT (9.8*10-7≤P<7.8*10-6). Loci (rs193139, rs7523050, rs1761621) in and near a gene rich region including G-protein-signaling modulator 2 (GPSM2) and syntaxin binding protein 3 (STXBP3) were significantly associated with lower body SAT depots (9.9*10-7≤P<9.5*10-6). GPSM2 is associated with cell division and cancer while STXBP3 is associated with glucose metabolism in adipoctyes. IPA identified atherosclerosis, mitochondrial function and T-Cell mediated apoptosis as processes related to SAT volume in HIV-infected individuals (P<5*10-3).
Our results are limited by the small sample size and replication is needed, however this genomic scan uncovered new genes associated with metabolism and inflammatory pathways that may affect SAT volume in ARV-treated HIV-infected patients.
HIV; HAART; GWAS; Subcutaneous Fat; SAT
Changes in body fat distribution and abnormal glucose metabolism are common in HIV-infected patients. We hypothesized that HIV-infected participants would have a higher prevalence of impaired glucose tolerance (IGT) compared with control subjects.
RESEARCH DESIGN AND METHODS
A total of 491 HIV-infected and 187 control participants from the second examination of the Study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM) underwent glucose tolerance testing (GTT). Multivariable regression was used to identify factors associated with GTT parameters.
The prevalence of impaired fasting glucose (IFG) (>110 mg/dL) was similar in HIV-infected and control participants (21 vs. 25%, P = 0.23). In those without IFG, the prevalence of IGT was slightly higher in HIV-infected participants compared with control subjects (13.1 vs. 8.2%, P = 0.14) and in HIV+ participants with lipoatrophy versus without (18.1 vs. 11.5%, P = 0.084). Diabetes detected by GTT was rare (HIV subjects 1.3% and control subjects 0%, P = 0.65). Mean 2-h glucose levels were 7.6 mg/dL higher in the HIV-infected participants (P = 0.012). Increased upper trunk subcutaneous adipose tissue (SAT) and decreased leg SAT were associated with 2-h glucose and IGT in both HIV-infected and control participants. Adjusting for adipose tissue reduced the estimated effects of HIV. Exercise, alcohol use, and current tenofovir use were associated with lower 2-h glucose levels in HIV-infected participants.
In HIV infection, increased upper trunk SAT and decreased leg SAT are associated with higher 2-h glucose. These body fat characteristics may identify HIV-infected patients with normal fasting glucose but nonetheless at increased risk for diabetes.
Lipodystrophy is commonly reported in Africa after antiretroviral therapy (ART) is initiated, but few studies have objectively measured changes in body composition. Body composition was determined in 76 HIV-infected participants from Mbarara, Uganda after starting a thymidine-analog regimen, and annual change was determined using repeated measures analysis. We measured skinfolds (tricep, thigh, subscapular, and abdomen), circumferences (arm, hip, thigh, waist), and total lean and fat mass (using bioelectric impedance analysis). A cross-sectional sample of 49 HIV-uninfected participants was studied for comparison. At baseline, most body composition measures were lower in HIV-infected than uninfected participants, but waist circumference was similar. After 12 months on ART, there was little difference in body composition measures between HIV-infected and uninfected participants; median waist circumference appeared higher in HIV-infected participants (79 vs. 75 cm; p = 0.090). Among HIV-infected participants, increases were observed in total lean and fat mass, circumference, and skinfold measures; only the increase in tricep skinfold did not reach statistical significance (+1.05 mm; 95% confidence interval: −0.24, 2.34; p = 0.11). Regional anthropometry in peripheral and central body sites increased over 12 months after ART initiation in HIV-infected persons from southwestern Uganda, suggesting a restoration to health. Gains in the tricep skinfold, a reliable marker of subcutaneous fat, appeared blunted, which could indicate an inhibitory effect of zidovudine on peripheral subcutaneous fat recovery.
Reduced kidney function and albuminuria are associated with higher risk for cardiovascular disease (CVD) and mortality in HIV-infected individuals. We investigated whether reduced estimated glomerular filtration rate (eGFR) and albuminuria are associated with subclinical vascular disease, as assessed by carotid intima-medial thickness (cIMT).
Cross-sectional analysis of 476 HIV-infected individuals without clinical evidence of CVD enrolled in the Fat Redistribution and Metabolic Change in HIV infection (FRAM) study, using multivariable linear regression. eGFRCys and eGFRCr were calculated from cystatin C and creatinine levels. Albuminuria was defined as a positive urine dipstick (≥1+) or urine albumin-to-creatinine ratio ≥30 mg/g. Common and internal cIMT were measured by high-resolution B-mode ultrasound.
In unadjusted analyses, eGFRCys and eGFRCr were strongly associated with common and internal cIMT. Each 10 ml/min/1.73 m2 decrease in eGFRCys and eGFRCr was associated with a 0.008 mm higher common cIMT (p = 0.003, p = 0.01) and a 0.024 and 0.029 mm higher internal cIMT (p = 0.003), respectively. These associations were eliminated after adjustment for age, gender, and race. Albuminuria showed little association with common or internal cIMT in all models.
In HIV-infected individuals without prior CVD, reduced kidney function and albuminuria were not independently associated with subclinical vascular disease, as assessed by cIMT. These results suggest that research should focus on searching for novel mechanisms by which kidney disease confers cardiovascular risk in HIV-infected individuals.
Cystatin C; Intima-medial thickness; HIV; Atherosclerosis; Cardiovascular disease; Kidney
Shear stress gradients and inflammation have been causally associated with atherosclerosis development in carotid bifurcation regions. The mechanism underlying higher levels of carotid intima-media thickness observed among HIV-infected individuals remains unknown.
Methods and Results
We measured carotid intima-media thickness progression and development of plaque in the common carotid, bifurcation region, and internal carotid artery in 300 HIV-infected persons and 47 controls. The median duration of follow-up was 2.4 years. When all segments were included, the rate of intima-media thickness progression was greater in HIV-infected subjects compared with controls after adjustment for traditional risk factors (0.055 vs. 0.024 mm/year, P=0.016). Rate of progression was also greater in the bifurcation region (0.067 vs. 0.025 mm/year, P=0.042) whereas differences were smaller in the common and internal regions. HIV-infected individuals had a greater incidence of plaque compared with controls in the internal (23% vs. 6.4%, P=0.0037) and bifurcation regions (34% vs. 17%, P=0.014). Among HIV-infected individuals, the rate of progression in the bifurcation region was more rapid compared with the common carotid, internal, or mean intima-media thickness; in contrast, progression rates among controls were similar at all sites. Baseline hsCRP was elevated in HIV-infected persons and was a predictor of progression in the bifurcation region.
Atherosclerosis progresses preferentially in the carotid bifurcation region in HIV-infected individuals. hsCRP, a marker of inflammation, is elevated in HIV and is associated with progression in the bifurcation region. These data are consistent with a model in which the interplay between hemodynamic shear stresses and HIV-associated inflammation contribute to accelerated atherosclerosis. (J Am Heart Assoc. 2012;1:jah3-e000422 doi: 10.1161/JAHA.111.000422.)
Clinical Trial Registration
URL: http://clinicaltrials.gov. Unique identifier: NCT01519141
AIDS; carotid arteries; inflammation; atherosclerosis
Skeletal muscle (SM) mass decreases with advanced age and with disease in HIV infection. It is unknown whether age-related muscle loss is accelerated in the current era of antiretroviral therapy and which factors might contribute to muscle loss among HIV-infected adults. We hypothesized that muscle mass would be lower and decline faster in HIV-infected adults than in similar-aged controls.
Whole-body 1H-magnetic resonance imaging was used to quantify regional and total SM in 399 HIV-infected and 204 control men and women at baseline and 5 years later. Multivariable regression identified associated factors.
At baseline and Year 5, total SM was lower in HIV-infected than control men. HIV-infected women were similar to control women at both time points. After adjusting for demographics, lifestyle factors, and total adipose tissue, HIV infection was associated with lower Year 5 SM in men and higher SM in women compared with controls. Average overall 5-year change in total SM was small and age related, but rate of change was similar in HIV-infected and control men and women. CD4 count and efavirenz use in HIV-infected participants were associated with increasing SM, whereas age and stavudine use were associated with decreasing SM.
Muscle mass was lower in HIV-infected men compared with controls, whereas HIV-infected women had slightly higher SM than control women after multivariable adjustment. We found evidence against substantially faster SM decline in HIV infected versus similar-aged controls. SM gain was associated with increasing CD4 count, whereas stavudine use may contribute to SM loss.
Sarcopenia; Lipoatrophy; Fat redistribution; Body composition
Previous research has demonstrated an increase in carotid intima–media thickness (cIMT) in HIV-infected individuals compared to controls. However, the reason for this increased level of subclinical vascular disease is unknown.
To identify HIV-related risk factors for increased cIMT.
We evaluated the relationship between HIV-related characteristics (including markers of HIV disease severity and use of antiretroviral therapy) and cIMT measurements in the internal/bulb and common carotid regions among 538 HIV-infected participants from the Study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM). We used Bayesian model averaging to estimate the posterior probability of candidate HIV and non-HIV-related risk factors being true predictors of increased cIMT. Variables with a posterior probability of more than 50% were used to develop a selected regression model for each of the anatomic regions.
For common cIMT, the Bayesian model selection process identified age, African-American race, and systolic and diastolic blood pressure with probability more than 95%, HDL cholesterol with probability 85% and Hispanic ethnicity with probability 51%. Among the HIV-related factors included in the analysis, only tenofovir use was selected (51% probability). In the selected model, duration of tenofovir use was associated with lower common cIMT (−0.0094 mm/year of use; 95% confidence interval: −0.0177 to −0.0010). For internal cIMT, no HIV-related risk factors were above the 50% posterior probability threshold.
We observed an inverse association between duration of tenofovir use and common carotid cIMT. Whether this association is causal or due to confounding by indication needs further investigation.
atherosclerosis; carotid intima–media thickness; HIV; tenofovir
Whether HIV viremia, particularly at low levels is associated with inflammation, increased coagulation, and all-cause mortality is unclear.
The associations of HIV RNA level with C-reactive protein (CRP), fibrinogen, interleukin (IL)-6 and mortality were evaluated in 1116 HIV-infected participants from the Study of Fat Redistribution and Metabolic Change in HIV infection. HIV RNA level was categorized as undetectable (i.e., “target not detected”), 1–19, 20–399, 400–9999, and ≥10,000 copies/ml. Covariates included demographics, lifestyle, adipose tissue, and HIV-related factors.
HIV RNA level had little association with CRP. Categories of HIV RNA below 10,000 copies/ml had similar levels of IL-6 compared with an undetectable HIV RNA level, while HIV RNA ≥10,000 copies/ml was associated with 89% higher IL-6 (p<0.001). This association was attenuated by ∼50% after adjustment for CD4+ cell count. Higher HIV RNA was associated with higher fibrinogen. Compared to an undetectable HIV RNA level, fibrinogen was 0.6%, 1.9%, 4.5%, 4.6%, and 9.4% higher across HIV RNA categories, respectively, and statistically significant at the highest level (p = 0.0002 for HIV RNA ≥10,000 copies/ml). Higher HIV RNA was associated with mortality during follow-up in unadjusted analysis, but showed little association after adjustment for CD4+ cell count and inflammation.
HIV RNA ≥10,000 copies/ml was associated with higher IL-6 and fibrinogen, but lower levels of viremia appeared similar, and there was little association with CRP. The relationship of HIV RNA with IL-6 was strongly affected by CD4 cell depletion. After adjustment for CD4+ cell count and inflammation, viremia did not appear to be substantially associated with mortality risk over 5 years.
To determine the association of inflammatory markers, fibrinogen and C-reactive protein (CRP), with 5-year mortality risk.
Vital status was ascertained in 922 HIV-infected participants from the Study of Fat Redistribution and Metabolic Change in HIV infection. Multivariable logistic regression estimated odds ratios (OR) after adjustment for demographic, cardiovascular and HIV-related factors.
Over a 5-year period, HIV-infected participants with fibrinogen levels in the highest tertile(>406mg/dL) had 2.6-fold higher adjusted odds of death than those with fibrinogen in the lowest tertile(<319mg/dL). Those with high CRP(>3mg/L) had 2.7-fold higher adjusted odds of death than those with CRP<1mg/L. When stratified by CD4 count category, fibrinogen (as a linear variable) remained independently associated [OR(95% confidence intervals) per 100mg/dL increase in fibrinogen: 1.93(1.57,2.37);1.43(1.14,1.79);1.43(1.14,1.81);and 1.30(1.04,1.63) for CD4 <200,200–350,>350–500, and >500cells/μL, respectively. Higher CRP also remained associated with higher odds of death overall and within each CD4 subgroup.
Fibrinogen and CRP are strong and independent predictors of mortality in HIV-infected adults. Our findings suggest that even in those with relatively preserved CD4 counts >500cells/μL, inflammation remains an important risk factor for mortality. Further investigation should determine whether interventions to reduce inflammation might decrease mortality risk in HIV-infected individuals.
HIV; inflammation; C-reactive protein; fibrinogen; mortality
Compared with controls, HIV-infected persons have a greater prevalence of kidney disease as assessed by high levels of cystatin C and albuminuria, but not as assessed by creatinine level. However, the clinical importance of elevated cystatin C and albuminuria in the HIV-infected population has not been studied.
We conducted an observational cohort study to determine the association of kidney disease (measured by albuminuria, cystatin C, and serum creatinine) with mortality.
Setting & Participants
922 HIV-infected persons enrolled in the FRAM (Fat Redistribution and Metabolic Change in HIV infection) study.
Serum cystatin C and serum creatinine were used to estimate glomerular filtration rate (eGFR). Albuminuria was defined as a positive urine dipstick (≥1+) or a urine albumin-creatinine ratio > 30 mg/g.
At baseline, reduced kidney function (eGFRSCysC <60 mL/min/1.73m2) or albuminuria was present in 28% of participants. After five years of follow-up, mortality was 48% among those with both eGFRSCysC <60 mL/min/1.73m2 and albuminuria, 23% in those with eGFRSCysC <60 mL/min/1.73m2 alone, 20% in those with albuminuria alone, and 9% in those with neither condition. After multivariable adjustment for demographics, cardiovascular risk factors, HIV-related factors, and inflammatory markers, eGFRSCysC <60 mL/min/1.73m2 and albuminuria were associated with nearly a twofold increase in mortality, whereas eGFRSCr <60 mL/min/1.73m2 did not appear to have any substantial association with mortality. Together, eGFRSCysC <60 mL/min/1.73m2 and albuminuria accounted for 17% of the population-level attributable risk for mortality.
Vital status was unknown in 261 participants from the original cohort.
Kidney disease marked by albuminuria or increased cystatin C levels appears to be an important risk factor for mortality in HIV-infected individuals. A substantial proportion of this risk may be unrecognized because of the current reliance on serum creatinine to estimate kidney function in clinical practice.
kidney disease; mortality; HIV infection
To determine the prevalence of illicit drug use and the impact on HIV treatment.
Multivariable regression of cross-sectional data from 1163 HIV-infected and 294 controls from the Study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM).
An analysis of (1) prevalence of specific illicit drug use (ever, current), (2) being on HAART among those with an indication and (3) current HIV RNA and CD4 cell count among HAART users.
Median age was 42 years, approximately 50% were non-Caucasian and 33% were women. Eighty-six percent of HIV-infected and 67% of controls reported ever using illicit drugs (P <0.0001); 28% of HIV-infected and 16% of controls reported current use (P = 0.0001). In adjusted models, current cocaine use and past heroin use were associated with not currently being on HAART. Among HAART users, those reporting past heroin use were as likely to have an undetectable HIV viral load as those who had never used heroin. Current and past cocaine use and current heroin use was associated with lower odds of undetectable HIV RNA. Past amphetamine use was associated with having an undetectable HIV. Similar results were seen for CD4 lymphocyte counts.
Illicit drug use in the US is common, although far fewer report current use than past use. Among HIV-infected patients, understanding of the type of illicit drugs used and whether drug use was in the past or ongoing is important, because of their differential effects on HIV treatment outcomes.
amphetamines; cocaine; heroin; HIV; street drugs; viral load
Microalbuminuria is associated with increased risk of cardiovascular disease and mortality. The objective of the study was to evaluate if HIV infection was an independent risk factor for microalbuminuria.
The relationship between HIV infection and microalbuminuria was assessed using subjects enrolled in the study of Fat Redistribution and Metabolic Change in HIV Infection, which consists of HIV-positive and control men and women. Participants with proteinuria (dipstick ≥1+) were excluded.
Microalbuminuria (urinary albumin/creatinine ratio, ACR>30 mg/g) was present in 11% of HIV infected, and 2% of control participants (P<0.001); a fivefold odds after multivariate adjustment (odds ratio, 5.11; 95% confidence interval, 1.97–13.31; P=0.0008). Several cardiovascular risk factors were associated with higher ACR in HIV participants: insulin resistance (HOMA>4; 32%, P<0.0001), systolic blood pressure (21%, P=0.01 for 120–140 versus <120 mmHg, and 43%, P <0.06 for >140 versus <120 mmHg), and family history of hypertension (17%, P=0.03). Higher CD4 cell count was associated with lower albumin/creatinine ratio (−24%, P=0.009 for 200–400 versus <200 cells/ml and −26%, P=0.005 for >400 versus <200 cells/ml).
HIV infection had a strong and independent association with microalbuminuria, the severity of which was predicted by markers of insulin resistance, hypertension, and advanced HIV infection. These associations warrant further investigation, as the increased prevalence of microalbuminuria in HIV infection may be a harbinger of future risk of cardiovascular and kidney diseases.
Microalbuminuria; kidney; urine protein; insulin resistance; lipodystrophy
Although studies have reported a high prevalence of end-stage renal disease in human immunodeficiency virus (HIV)-infected individuals, little is known about moderate impairments in kidney function. Cystatin C measurement may be more sensitive than creatinine for detecting impaired kidney function in persons with HIV.
We evaluated kidney function in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM) cohort, a representative sample of 1008 HIV-infected persons and 290 controls from the Coronary Artery Risk Development in Young Adults (CARDIA) study in the United States.
Cystatin C level was elevated in HIV-infected individuals; the mean±SD cystatin C level was 0.92±0.22 mg/L in those infected with HIV and 0.76±0.15 mg/L in controls (P<.001). In contrast, both mean creatinine levels and estimated glomerular filtration rates appeared similar in HIV-infected individuals and controls (0.87±0.21 vs 0.85±0.19 mg/dL [to convert to micromoles per liter, multiply by 88.4] [P=.35] and 110±26 vs 106±23 mL/min/1.73 m2 [P=.06], respectively). Persons with HIV infection were more likely to have a cystatin C level greater than 1.0 mg/L (OR, 9.8; 95% confidence interval, 4.4-22.0 [P<.001]), a threshold demonstrated to be associated with increased risk for death and cardiovascular and kidney disease. Among participants with HIV, potentially modifiable risk factors for kidney disease, hypertension, and low high-density lipoprotein concentration were associated with a higher cystatin C level, as were lower CD4 lymphocyte count and coinfection with hepatitis C virus (all P<.001).
Individuals infected with HIV had substantially worse kidney function when measured by cystatin Clevel compared with HIV-negative controls, whereas mean creatinine levels and estimated glomerular filtration rates were similar. Cystatin C measurement could be a useful clinical tool to identify HIV-infected persons at increased risk for kidney and cardiovascular disease.
Hepatic steatosis is common in persons with HIV and hepatitis C virus (HCV); yet biopsy measurement of steatosis is prone to sampling error. We compared magnetic resonance spectroscopy (MRS) measurement of steatosis to histology in HIV/HCV-coinfected patients, and explored the associated adipose tissue and metabolic factors.
Cross-sectional analysis of 42 HIV/HCV-coinfected men and women. Logistic regression analysis identified factors [MRI-measured visceral adipose tissue (VAT) and abdominal subcutaneous adipose tissue (SAT) and Homeostasis Model Assessment (HOMA) estimated insulin resistance] associated with histologic steatosis (≥5% of hepatocytes with fat) and MRS steatosis (≥5% of hepatic fat).
MRS steatosis was strongly associated with histologic steatosis, when measured continuously [odds ratio: 10.2 per doubling of MRS-measured hepatic fat; 95% confidence interval (CI):2.9, 69.3] and dichotomously (Kappa coefficient=0.52; p=0.0007). Four of the 10 with MRS-measured steatosis did not have histologic steatosis; 3 of 9 with histologic steatosis did not have MRS-measured steatosis (67% sensitivity; 88% specificity). Associations of VAT and abdominal SAT were associated with both histologic and MRS-measured steatosis. Insulin resistance was also associated with both.
When compared to histology, MRS was similarly associated with adipose tissue and metabolic factors. MRS is a useful non-invasive alternative to biopsy in HIV/HCV coinfection.
Steatosis; Magnetic Resonance Spectroscopy; HIV; HCV; Adipose tissue; Insulin Resistance