Interruption of antiretroviral therapy is associated with increased plasma cystatin C

Creatinine and cystatin C-based estimated glomerular filtration rate estimates of kidney function in Black people with HIV on antiretroviral therapy

BACKGROUND

To reduce health inequalities, the creatinine-based chronic kidney disease epidemiology collaboration 2021 formula for estimated glomerular filtration rate (eGFR) is replacing the 2009 formula, which required adjustment specifically for Black individuals. We compared the 2021 and 2009 creatinine-based formulae with cystatin C-based eGFR in Black people on antiretroviral therapy (ART) with HIV RNA <200 c/ml.

METHODS

Cross-sectional analysis of paired serum creatinine and cystatin C measurements. Bias, imprecision, accuracy, and performance for identifying individuals with eGFR cystatin C <60 (units: ml/min per 1.73 m 2 ) were determined. The effects of ART with no, mild-moderate, or marked effect on tubular creatinine secretion on the performance of the 2021 formula was assessed.

RESULTS

We included 362 individuals (mean age 51 years, 56% female, mean eGFR-cystatin C 88.3). Overall, the 2021 (vs. the 2009 race-adjusted) formula was less biased and had improved imprecision and accuracy compared with eGFR-cystatin C but underestimated eGFR-cystatin C in those with eGFR ≥90 and overestimated eGFR-cystatin C in those with eGFR <60. The 2021 (vs. the 2009) formula had high specificity (95% vs. 97%) and negative predictive value (97% vs. 96%), but low sensitivity (56% vs. 52%) and positive predictive value (44% vs. 54%) for identifying individuals with eGFR-cystatin C <60 ( P  > 0.25). Performance at the eGFR <60 cut-off was minimally affected by ART exposure group.

CONCLUSION

The CKD-EPI 2021 creatinine-based formula was better aligned with eGFR-cystatin C than the 2009 formula. eGFR-cystatin C may provide clinically useful information in Black people with eGFR <60 irrespective of ART regimen.

Cross-Sectional and Longitudinal Performance of Creatinine- and Cystatin C-Based Estimating Equations Relative to Exogenously Measured Glomerular Filtration Rate in HIV-Positive and HIV-Negative Persons

BACKGROUND

Reliable estimates of glomerular filtration rate (GFR) are important in the clinical management of HIV-positive patients. Data on the performance of widely used estimating equations (eGFR) relative to exogenously measured GFR are sparse in this population.

METHODS

We evaluated cross-sectional and longitudinal accuracy and bias of eGFR, based on creatinine and cystatin C, relative to disappearance of infused iohexol from plasma (iGFR) in a cohort of participants followed annually for up to 7 years.

RESULTS

A total of 222 HIV-positive and 139 HIV-negative participants contributed 1240 visits with valid iGFR and eGFR measures. Estimated GFR based on both creatinine and cystatin C performed the best. Estimated GFR based on creatinine alone overestimated iGFR by 9 mL·min·1.73 m on average and was significantly less accurate in HIV-positive than HIV-negative individuals. The performance of equations based on either creatinine alone or cystatin C alone were significantly affected by participant factors (eg, non-suppressed HIV RNA, nadir CD4 count, hepatitis C virus coinfection). The average iGFR slope was -4% per year in HIV-positive participants. In both HIV-positive and HIV-negative participants, eGFR slope measures were generally unbiased but inaccurate, with only 60%-74% of observations falling within ±5% points of iGFR slope.

CONCLUSIONS

Both creatinine and cystatin C have limitations as GFR indices in HIV-positive individuals. Estimated GFR based on both creatinine and cystatin C performed best in our study and may be preferred in HIV-positive persons with kidney disease or comorbidities that place them at high risk for kidney disease.

Serum Cystatin C and Coronavirus Disease 2019: A Potential Inflammatory Biomarker in Predicting Critical Illness and Mortality for Adult Patients

This study aimed at determining the relationship between baseline cystatin C levels and coronavirus disease 2019 (COVID-19) and investigating the potential prognostic value of serum cystatin C in adult patients with COVID-19. 481 patients with COVID-19 were consecutively included in this study from January 2, 2020, and followed up to April 15, 2020. All clinical and laboratory data of COVID-19 patients with definite outcomes were reviewed. For every measure, COVID-19 patients were grouped into quartiles according to the baseline levels of serum cystatin C. The highest cystatin C level was significantly related to more severe inflammatory conditions, worse organ dysfunction, and worse outcomes among patients with COVID-19 (P values < 0.05). In the adjusted logistic regression analyses, the highest cystatin C level and ln-transformed cystatin C levels were independently associated with the risks of developing critically ill COVID-19 and all-cause death either in overall patients or in patients without chronic kidney disease (P values < 0.05). As a potential inflammatory marker, increasing baseline levels of serum cystatin C might independently predict adverse outcomes for COVID-19 patients. Serum cystatin C could be routinely monitored during hospitalization, which showed clinical importance in prognosticating for adult patients with COVID-19.

[Nephrotoxicity of antiretrovirals other than tenofovir]

The remarkable improvement of the outcome of HIV infection came with the price of substantial toxicity of some antiretrovirals. The first molecules used to treat HIV included an important nephrotoxicity. Zalcitabine, stavudine and didanosine can induce severe lactic acidosis. Lactate production is enhanced and the renal capacity to regulate pH is overwhelmed. However, this side effect is not due to a direct dysfunction of the kidneys. Zalcitabine was withdrawn from the market because of this risk. Indinavir, a protease inhibitor, is soluble only in very acidic solutions. Consequently, the small fraction that is excreted in the urine precipitates and can be responsible for uro-nephrolithiasis, leukocyturia, cristalluria, obstructive acute kidney failure, and acute or chronic interstitial nephritis. This is the reason why indinavir is almost not prescribed nowadays, even if it is still marketed. In addition to the direct nephrotoxicity of some antiretrovirals, anti-HIV treatment also includes a toxicity which pathophysiology is not completely elucidated. This nephrotoxicity is the consequence of organ accelerated ageing and of an increased vascular risk. Kidney vascularization (from renal arteries to capillaries) is essential to kidney function and all cardiovascular risks are also renal risks. It is now clearly established that combined antiretroviral treatment increases the vascular risk. A better comprehension of the links between HIV infection, its treatment and very long-term kidney risk is needed to improve the complex management of patients who have now cumulated several decades of HIV infection and treatment with various toxicities.

Cystatin C: A Marker for Inflammation and Renal Function Among HIV-infected Children and Adolescents

BACKGROUND

Renal disease is a leading cause of morbidity in HIV-infected adults in the highly active antiretroviral therapy (HAART) era. Cystatin C has been proposed as a more sensitive marker of renal function, but it may be affected by ongoing inflammation. We aimed to study the cystatin C levels in a cohort of HIV-infected pediatric patients at 3 Spanish centers.

METHODS

This is a multicenter cross-sectional observational study. Renal function was assessed by means of first morning urine protein/creatinine and albumin/creatinine ratios and creatinine-estimated glomerular filtration rates (GFRs), together with the following inflammation markers: cystatin C, reactive C protein, β-2-microglobulin and 25(OH)-vitamin D levels. A control group of healthy children and adolescents was used.

RESULTS

Eighty-three patients (51 females, median age: 13.3 years; 32 males, median age: 13.6 years) and 44 controls (24 females, median age: 12.2 years; 20 males, median age: 10.9 years) were included. Among the former, mean CD4 cell count was 860/mm, 29(35%) patients had a previous AIDS diagnosis, 73(88%) were on HAART and HIV viremia was undetectable in 61(73%). No differences in cystatin C levels were observed between the 2 groups. In HIV-infected patients, cystatin C levels correlated with GFR (r = -0.27; P = 0.01), age at first HAART (r = -0.21; P = 0.05), and β-2-microglobulin (r = 0.569; P < 0.01). In multivariate analysis, lower GFR (P = 0.014) and higher β-2-microglobulin levels (P = 0.001) remained as independent risk factors for higher cystatin C values.

CONCLUSIONS

Cystatin C values were associated with GFR and β-2-microglobulin. Cystatin C may be useful as a marker of renal function in HIV-infected pediatric patients, independently of ongoing inflammation or viremia.

Reductions in Plasma Cystatin C After Initiation of Antiretroviral Therapy Are Associated With Reductions in Inflammation: ACTG A5224s

BACKGROUND

Among patients with HIV infection, changes in the kidney filtration marker cystatin C after initiation of antiretroviral therapy (ART) may be related to changes in body composition or biomarkers of inflammation.

METHODS

ACTG A5224s was a substudy of A5202, which randomly assigned ART-naive HIV-infected subjects to blinded abacavir/lamivudine (ABC/3TC) or tenofovir/emtricitabine (TDF/FTC) with open-label efavirenz (EFV) or ritonavir-boosted atazanavir. This analysis explored changes in cystatin C from 0 to 96 weeks.

RESULTS

Of the 269 subjects, 85% were male and 66% white non-Hispanics; baseline mean CD4 count was 236 cells per cubic millimeter and cystatin C was 0.89 mg/L. Cystatin C decreased significantly within each arm; however, ritonavir-boosted atazanavir attenuated the beneficial effects of ART on cystatin C compared to EFV. Compared to ABC/3TC, TDF/FTC led to a marginally significant attenuation for percent change analyses only. Higher baseline body mass index and HIV RNA were associated with larger reductions in cystatin C in multivariable models. At baseline, cystatin C was positively correlated with high-sensitivity C-reactive protein (Spearman r = 0.25), interleukin 6 (r = 0.34), soluble intercellular adhesion molecule (r = 0.36), soluble vascular cell adhesion molecule (r = 0.54), tumor necrosis factor α (r = 0.57), and soluble TNF-α receptor I (r = 0.70, all P < 0.001). Reductions in cystatin C from 0 to 96 weeks correlated with reductions in all inflammatory biomarkers (r = 0.39-0.58, P < 0.001) except for high-sensitivity C-reactive protein (r = 0.01, P = 0.89) and IL-6 (r = 0.08, P = 0.24).

CONCLUSIONS

The beneficial effect of ART on cystatin C concentrations is attenuated by boosted ATV when compared to EFV. Reductions in cystatin C after ART are associated with reductions in systemic inflammation.

Urinary biomarkers of kidney diseases in HIV-infected children

A significant number of children infected with the human immunodeficiency virus 1 (HIV-1) virus all over the world are at risk of developing renal diseases that could have a significant impact on their treatment and quality of life. It is necessary to identify children undergoing the early stages of these renal diseases, as well as the potential renal toxicity that could be caused by antiretroviral drugs, in order to prevent the development of cardiovascular complications and chronic renal failure. This article describes the most common renal diseases seen in HIV-infected children, as well as the value and limitations of the clinical markers that are currently being used to monitor their renal function and histological damage in a noninvasive manner. In addition, we discuss the progress made during the last 10 years in the discovery and validation of new renal biomarkers for HIV-infected children and young adults. Although significant progress has been made during the early phases of the biomarkers discovery, more work remains to be done to validate the new biomarkers in a large number of patients. The future looks promising, however, the new knowledge needs to be integrated and validated in the context of the clinical environment where these children are living.

HIV-related metabolic comorbidities in the current ART era

Despite effective antiretroviral therapy (ART), HIV-infected individuals have residual chronic immune activation that contributes to the pathogenesis of HIV infection. This immune system dysregulation is a pathogenic state manifested by very low naïve T-cell numbers and increased terminally differentiated effector cells that generate excessive proinflammatory cytokines with limited functionality. Immune exhaustion leaves an individual at risk for accelerated aging-related diseases, including renal dysfunction, atherosclerosis, diabetes mellitus, and osteoporosis. We highlight research that clarifies the role of HIV, ART, and other factors that contribute to the development of these diseases among HIV-infected persons.

Increased systemic immune activation and inflammatory profile of long-term HIV-infected ART-controlled patients is related to personal factors, but not to markers of HIV infection severity

OBJECTIVES

The objective of this study was to analyse the respective roles of personal factors and HIV infection markers on the systemic immune activation/inflammatory profile of long-term antiretroviral treatment-controlled patients.

PATIENTS AND METHODS

A panel of soluble immune activation/inflammatory biomarkers was measured in 352 HIV-infected treatment-controlled patients from the APROCO-COPILOTE cohort, all of whom were started on a PI in 1997-99 and had a final evaluation 11 years later, and in 59 healthy controls.

RESULTS

A total of 81.5% of the patients were male, with the following characteristics: median age 49 years; 620 CD4 cells/mm(3); 756 CD8 cells/mm(3); CD4/CD8 ratio 0.81; BMI 23.0 kg/m(2); waist-to-hip ratio 0.95. Markers of inflammation-high-sensitivity (hs) IL-6 (median and IQR) (1.3 pg/L, 0.7-2.6), hs C-reactive protein (CRP) (2.1 mg/L, 0.9-4.5) and D-dimer (252 ng/mL, 177-374)-were elevated compared with healthy controls (P < 0.001) and strongly related to each other, as were markers of immune activation [soluble (s) CD14 (1356 ng/mL, 1027-1818), β2-microglobulin (2.4 mg/L, 2.0-3.1) and cystatin-C (0.93 mg/L, 0.82-1.1)]. Inflammatory and immune activation markers were also associated with each other. In HIV-infected patients: age was related to D-dimer, β2-microglobulin and cystatin-C levels; being a smoker was related to increased IL-6 and cystatin-C; and BMI and waist-to-hip ratio were related to CRP. Conversely, markers of HIV infection, current CD4 or CD8 values, CD4 nadir, CD4/CD8 ratio, AIDS stage at initiation of PIs, current viral load and duration of ART were not associated with immune activation/inflammation markers.

CONCLUSIONS

In these long-term treatment-controlled HIV-infected patients, all systemic markers of inflammation and immune activation were increased compared with healthy controls. This was related to demographic and behavioural factors, but not to markers of severity of the HIV infection. Intervention to decrease low-grade inflammation must thus prioritize modifiable personal factors.

Comparison of cystatin C and creatinine to determine the incidence of composite adverse outcomes in HIV-infected individuals

BACKGROUND

Cystatin C is an overall biomarker of pathophysiologic abnormalities that accompany chronic kidney disease (CKD). The utility of cystatin C is not fully understood in an HIV-infected population.

METHODS

This prospective study investigated 661 HIV-infected individuals for 4 years to determine the incidence of adverse outcomes, including all-cause mortality, cardiovascular disease, and renal dysfunction. The risk of developing the outcomes was discriminated with a 4 color-coded classification in a 3 × 6 contingency table, that combined 3 grades of dipstick proteinuria with 6 grades of estimated glomerular filtration rate (eGFR) calculated using either serum creatinine (eGFRcr) or cystatin C (eGFRcy): green, low risk; yellow, moderately increased risk; orange, high risk; and red, very high risk. The cumulative incidence of the outcomes was assessed by the Kaplan-Meier method, and the association between color-coded risk and the time to outcome was evaluated using multivariate proportional hazards analysis.

RESULTS

Compared with eGFRcr, the use of eGFRcy reduced the prevalence of risk ≥ orange by 0.8%. The adverse outcomes were significantly more likely to occur to the patients with baseline risk category ≥orange than those with ≤ yellow, independent of risk categories based on eGFRcr or eGFRcy. However, in multivariate analysis, risk category ≥orange with eGFRcy-based classification was significantly associated with adverse outcomes, but not the one with eGFRcr.

CONCLUSIONS

Replacing creatinine by cystatin C in the CKD color-coded risk classification may be appropriate to discriminate HIV-infected patients at increased risk of a poor prognosis.

HIV viremia and T-cell activation differentially affect the performance of glomerular filtration rate equations based on creatinine and cystatin C

BACKGROUND

Serum creatinine and cystatin C are used as markers of glomerular filtration rate (GFR). The performance of these GFR markers relative to exogenously measured GFR (mGFR) in HIV-positive individuals is not well established.

METHODS

We assessed the performance of the chronic kidney disease epidemiology collaboration equations based on serum concentrations of creatinine (eGFRcr), cystatin C (eGFRcys) and both biomarkers combined (eGFRcr-cys) in 187 HIV-positive and 98 HIV-negative participants. Measured GFR was calculated by plasma iohexol clearance. Bias and accuracy were defined as the difference between eGFR and mGFR and the percentage of eGFR observations within 30% of mGFR, respectively. Activated CD4 and CD8 T-cells (CD38+ HLA-DR+) were measured by flow cytometry.

RESULTS

The median mGFR was >100 ml/min/1.73 m(2) in both groups. All equations tended to be less accurate in HIV-positive than in HIV-negative subjects, with eGFRcr-cys being the most accurate overall. In the HIV-positive group, eGFRcys was significantly less accurate and more biased than eGFRcr and eGFRcr_cys. Additionally eGFRcys bias and accuracy were strongly associated with use of antiretroviral therapy, HIV RNA suppression, and percentages of activated CD4 or CD8 T-cells. Hepatitis C seropositivity was associated with larger eGFRcys bias in both HIV-positive and HIV-negative groups. In contrast, eGFRcr accuracy and bias were not associated with HIV-related factors, T-cell activation, or hepatitis C.

CONCLUSIONS

The performance of eGFRcys relative to mGFR was strongly correlated with HIV treatment factors and markers of T-cell activation, which may limit its usefulness as a GFR marker in this population.

Glomerular filtration rate estimated using creatinine, cystatin C or both markers and the risk of clinical events in HIV-infected individuals

OBJECTIVES

The accuracy and precision of glomerular filtration rate (GFR) estimating equations based on plasma creatinine (GFR(cr)), cystatin C (GFR(cys)) and the combination of these markers (GFR(cr-cys)) have recently been assessed in HIV-infected individuals. We assessed the associations of GFR, estimated by these three equations, with clinical events in HIV-infected individuals.

METHODS

We compared the associations of baseline GFR(cr), GFR(cys) and GFR(cr-cys) [using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations] with mortality, cardiovascular events (CVEs) and opportunistic diseases (ODs) in the Strategies for the Management of Antiretroviral Therapy (SMART) study. We used Cox proportional hazards models to estimate unadjusted and adjusted hazard ratios per standard deviation (SD) change in GFR.

RESULTS

A total of 4614 subjects from the SMART trial with available baseline creatinine and cystatin C data were included in this analysis. Of these, 99 died, 111 had a CVE and 121 had an OD. GFR(cys) was weakly to moderately correlated with HIV RNA, CD4 cell count, high-sensitivity C-reactive protein, interleukin-6, and D-dimer, while GFR(cr) had little or no correlation with these factors. GFR(cys) had the strongest associations with the three clinical outcomes, followed closely by GFR(cr-cys), with GFR(cr) having the weakest associations with clinical outcomes. In a model adjusting for demographics, cardiovascular risk factors, HIV-related factors and inflammation markers, a 1-SD lower GFR(cys) was associated with a 55% [95% confidence interval (CI) 27-90%] increased risk of mortality, a 21% (95% CI 0-47%) increased risk of CVE, and a 22% (95% CI 0-48%) increased risk of OD.

CONCLUSIONS

Of the three CKD-EPI GFR equations, GFR(cys) had the strongest associations with mortality, CVE and OD.

Renal toxicity associated with antiretroviral therapy

Renal disease is becoming an increasingly prevalent comorbidity in patients with human immunodeficiency virus (HIV) infection. The increase in life expectancy following the introduction of highly active antiretroviral therapy (HAART) and the long-term development of metabolic complications (such as diabetes and dyslipidaemia), hypertension, and vascular diseases can contribute to the increasing frequency in the recognition of renal impairment in HIV-infected patients. Some antiretroviral agents, and particularly tenofovir, have been associated with nephrotoxic drug effects, including decline in glomerular filtration rate, proximal tubular damage, and acute kidney injury. The occurrence of clinically evident renal toxicity in patients treated with HAART seems to be very low, but glomerular or tubular subclinical dysfunction may occur more frequently. Therefore, careful clinical and laboratory monitoring for the early recognition of renal abnormalities is recommended for all subjects receiving antiretroviral treatment. In this article, the current knowledge about the nephrotoxic effects of antiretroviral agents has been reviewed, and an algorithm for screening and management of HAART-related kidney disease is proposed in the light of the most recent clinical studies and international guidelines.

Risk factors for ESRD in HIV-infected individuals: traditional and HIV-related factors

BACKGROUND

Despite improvements in survival with human immunodeficiency virus (HIV) infection, kidney disease remains an important complication. Few studies have evaluated risk factors associated with the development of end-stage renal disease (ESRD) in HIV-infected individuals. We sought to identify traditional and HIV-related risk factors for ESRD in HIV-infected individuals and compare ESRD risk by estimated glomerular filtration rate (eGFR) and proteinuria levels.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

22,156 HIV-infected veterans without pre-existing ESRD receiving health care in the Veterans' Affairs medical system between 1996 and 2004.

PREDICTORS

Hypertension, diabetes, cardiovascular disease, hypoalbuminemia (serum albumin <3.5 mg/dL), CD4 lymphocyte count, HIV viral load, hepatitis C virus coinfection, proteinuria, and eGFR were identified using the Veterans' Affairs electronic record system.

OUTCOMES

ESRD was ascertained by the US Renal Data System.

RESULTS

366 cases of ESRD occurred, corresponding to 3 cases/1,000 person-years. Hypertension (HR, 1.9; 95% CI, 1.5-2.4), diabetes (HR, 1.7; 95% CI, 1.3-2.2), and cardiovascular disease (HR, 2.2; 95% CI, 1.7-2.7) were associated independently with ESRD risk in multivariate-adjusted models, as were CD4 lymphocyte count <200 cells/μL (HR, 1.5; 95% CI, 1.2-2.0), HIV viral load ≥30,000 copies/mL (HR, 2.0; 95% CI, 1.5-2.8), hepatitis C virus coinfection (HR, 1.9; 95% CI, 1.5-2.4), and hypoalbuminemia (HR, 2.1; 95% CI, 1.8-2.5). Compared with persons without chronic kidney disease, defined as eGFR >60 mL/min/1.73 m(2) and no proteinuria, lower eGFR and higher proteinuria categories were associated jointly with exponentially higher ESRD rates, ranging from 6.6 events/1,000 person-years for persons with urine protein excretion of 30-100 mg/dL and eGFR >60 mL/min/1.73 m(2) to 193 events/1,000 person-years for persons with urine protein excretion ≥300 mg/dL and eGFR <30 mL/min/1.73 m(2).

LIMITATIONS

Results may not be generalizable to female and nonveteran populations.

CONCLUSIONS

In HIV-infected persons, ESRD risk appears attributable to a combination of traditional and HIV-related risk factors for kidney disease. Combining eGFR and proteinuria for chronic kidney disease staging is most effective for stratifying the risk of ESRD.

Cystatin C and baseline renal function among HIV-infected persons in the SUN Study

In the combination antiretroviral therapy (cART) era, renal dysfunction remains common. The Study to Understand the Natural History of HIV/AIDS in the Era of Effective Therapy (SUN) (ClinicalTrials.gov number, NCT00146419) is a prospective observational cohort study of HIV-infected adults. At baseline, comprehensive data were collected, including cystatin C and measures of renal function. Univariate and multivariate regression analyses were performed to identify factors associated with baseline renal dysfunction [estimated glomerular filtration rate (eGFR) < 90 ml/min/1.73 m(2) calculated using the simplified Modification of Diet in Renal Disease equation] and elevated cystatin C (>1.0 mg/liter) in a cross-sectional analysis. Among 670 subjects with complete data (mean age 41 years, mean CD4 cell count 530 cells/mm(3), 79% prescribed cART), the mean eGFR was 96.8 ml/min/1.73 m(2). Forty percent of subjects had renal dysfunction; 3.3% had chronic kidney disease (eGFR < 60 ml/min/1.73 m(2)). Elevated cystatin C was present in 18% of subjects. In multivariate analysis, renal dysfunction was associated with older age, non-Hispanic white race/ethnicity, higher body mass index (BMI), hypertension, higher cystatin C levels, and current prescription of ritonavir. Factors associated with elevated cystatin C included hepatitis C coinfection, hypertension, current smoking, older age, current tenofovir use, detectable plasma HIV RNA, and elevated microalbuminuria. The prevalence of chronic kidney disease (CKD) was low in this contemporary HIV cohort. However, mild to moderate renal dysfunction was common despite the widespread use of cART.

Clinically significant drug interactions with antacids: an update

One may consider that drug-drug interactions (DDIs) associated with antacids is an obsolete topic because they are prescribed less frequently by medical professionals due to the advent of drugs that more effectively suppress gastric acidity (i.e. histamine H(2)-receptor antagonists [H2RAs] and proton pump inhibitors [PPIs]). Nevertheless, the use of antacids by ambulant patients may be ever increasing, because they are freely available as over-the-counter (OTC) drugs. Antacids consisting of weak basic substances coupled with polyvalent cations may alter the rate and/or the extent of absorption of concomitantly administered drugs via different mechanisms. Polyvalent cations in antacid formulations may form insoluble chelate complexes with drugs and substantially reduce their bioavailability. Clinical studies demonstrated that two classes of antibacterials (tetracyclines and fluoroquinolones) are susceptible to clinically relevant DDIs with antacids through this mechanism. Countermeasures against this type of DDI include spacing out the dosing interval - taking antacid either 4 hours before or 2 hours after administration of these antibacterials. Bisphosphonates may be susceptible to DDIs with antacids by the same mechanism, as described in the prescription information of most bisphosphonates, but no quantitative data about the DDIs are available. For drugs with solubility critically dependent on pH, neutralization of gastric fluid by antacids may alter the dissolution of these drugs and the rate and/or extent of their absorption. However, the magnitude of DDIs elicited by antacids through this mechanism is less than that produced by H2RAs or PPIs; therefore, the clinical relevance of such DDIs is often obscure. Magnesium ions contained in some antacid formulas may increase gastric emptying, thereby accelerating the rate of absorption of some drugs. However, the clinical relevance of this is unclear in most cases because the difference in plasma drug concentration observed after dosing shortly disappears. Recent reports have indicated that some of the molecular-targeting agents such as the tyrosine kinase inhibitors dasatinib and imatinib, and the thrombopoietin receptor agonist eltrombopag may be susceptible to DDIs with antacids. Finally, the recent trend of developing OTC drugs as combination formulations of an antacid and an H2RA is a concern because these drugs will increase the risk of DDIs by dual mechanisms, i.e. a gastric pH-dependent mechanism by H2RAs and a cation-mediated chelation mechanism by antacids.

Recent progress in HIV-associated nephropathy

The classic kidney disease of HIV infection, HIV-associated nephropathy (HIVAN), is an aggressive form of collapsing focal segmental glomerulosclerosis with accompanying tubular and interstitial lesions. HIVAN was first described among African-Americans and Haitian immigrants with advanced HIV disease, an early suggestion of a strong genetic association. This genetic susceptibility was recently linked to polymorphisms on chromosome 22 in individuals of African descent. The association with advanced HIV infection and evidence from HIV-transgenic mice suggested the possibility that HIV directly infects the kidney and that specific HIV gene expression induces host cellular pathways that are responsible for HIVAN pathogenesis. Although combination antiretroviral therapy has substantially reduced the impact of HIVAN in the United States, continued growth of the HIV epidemic in susceptible African populations may have important public health implications. This article reviews recent progress in the pathogenesis and treatment of HIVAN and describes the changing epidemiology of HIV-related kidney disease.

Resumption of HIV replication is associated with monocyte/macrophage derived cytokine and chemokine changes: results from a large international clinical trial

BACKGROUND

There is increasing interest in the role of immune activation and inflammation in HIV disease, but data on direct effects of HIV replication on immune cell activation are limited.

METHODS

High sensitivity multiplex bead array assays (MBAAs) were used to measure changes in plasma cytokines and chemokines [interleukin (IL)-1β, IL-2, IL-6, IL-7, IL-8, IL-12p70, IL-17, tumor necrosis factor-α (TNFα), interferon-γ, granulocyte macrophage colony-stimulating factor, IL-4, IL-5, IL-10, IL-13, CXCL10] from randomization (month 0) to month 2 in a random sample of 200 patients from both the drug conservation (DC) and viral suppression (VS) arms of the Strategies for Management of Antiretroviral Therapy (SMART) trial. IL-6 was also measured by ELISA. Data were evaluated using nonparametric correlation and censored parametric analysis of covariance and associations were declared as statistically significant when the Bonferroni-adjusted P-value was less than 0.003.

RESULTS

Compared with the VS arm, significant increases were seen in the DC arm for TNFα (+0.34 log(e) pg/ml, P = 0.0001), IL-10 (+0.33 log(e) pg/ml, P = 0.00001) and CXCL10 (+0.66 log(e) pg/ml, P = 0.00001). IL-6 ELISA poorly correlated with IL-6 MBAA (Spearman's rho = 0.29, P = 0.0001).

CONCLUSION

Resumption of HIV replication after ceasing antiretroviral therapy is associated predominantly with an increase of monocyte/macrophage-derived cytokines. Measurement of IL-6 levels may be affected by assay method and this should be considered in future studies of biomarkers.

Antiretroviral treatment interruption leads to progression of liver fibrosis in HIV-hepatitis C virus co-infection

OBJECTIVE

Despite potential negative consequences, HIV/hepatitis C virus (HCV) co-infected patients may discontinue antiretroviral treatment (ART) for several reasons. We examined the impact of ART interruption on liver fibrosis progression in co-infected adults, using the aspartate aminotransferase-to-platelet ratio index (APRI) as a surrogate marker of liver fibrosis.

METHOD

Data were analyzed from a multisite prospective cohort of 541 HIV-HCV co-infected adults. ART interruption was included as a time-updated variable and defined as the cessation of all antiretrovirals for at least 14 days. The primary endpoint was the development of an APRI score at least 1.5. Time-dependent Cox proportional hazards regression and inverse probability-of-treatment weighting (IPTW) in a marginal structural model were used to evaluate the association of baseline and time-varying covariates with developing significant fibrosis.

RESULTS

Patients were followed for a median of 1.02 years; 10% (n = 53) interrupted ART and 10% (n = 53) developed significant fibrosis. After accounting for potential confounders, including CD4 T-cell count, HIV viral load, baseline APRI score, age and gender, the hazard ratio for ART interruption was 2.52 (95% confidence interval 1.20-5.28). Use of IPTW resulted in a similar effect estimate, suggesting that mediation by time-varying confounders was negligible.

CONCLUSION

ART interruption was associated with an increased risk of fibrosis progression in HIV-HCV co-infection that was only partially accounted for by HIV viral load and CD4 T-cell counts. Our findings suggest that liver disease progression observed in ART-treated co-infected patients is partly due to the consequences of treatment interruptions.

Expert opinion on pharmacotherapy of kidney disease in HIV-infected patients

INTRODUCTION

Human immunodeficiency virus (HIV) infection is associated with the development of a wide spectrum of kidney diseases. HIV-associated nephropathy (HIVAN) is the most common cause of chronic kidney disease (CKD) in HIV-infected individuals and predominantly affects patients of African ancestry. HIVAN is a leading cause of end-stage renal disease (ESRD) among African-Americans.

AREAS COVERED

An overview of the spectrum of kidney disease in patients with HIV is given. Current pharmacologic interventions to treat kidney disease in HIV are discussed. This review will enhance knowledge regarding the most common causes of kidney disease in HIV-infected patients. An understanding of the principles related to pharmacotherapy in HIV-infected patients with kidney disease will also be gained.

EXPERT OPINION

Kidney disease is an important cause of morbidity and mortality in HIV-infected patients. The most common cause of chronic kidney disease in this population is HIV-associated nephropathy, which is caused by viral infection of the renal epithelium. Several medications that are commonly used in HIV-infected patients can have adverse effects on the kidneys and the doses of many antiretroviral medications need to be adjusted in patients with impaired renal function.

Biomarkers of impaired renal function

PURPOSE OF REVIEW

Renal disease is increasingly common as life expectancy of HIV-infected persons continues to improve. Several biomarkers are available for monitoring renal function, although no consensus exists on how best to apply these tools in HIV infection. This review describes recent findings for the more common renal biomarkers.

RECENT FINDINGS

Although widely used in clinical practice, creatinine-based estimates of glomerular filtration rate have not been validated in HIV infection. Serum cystatin C has been proposed as a more sensitive marker of renal dysfunction in HIV infection, although it may also reflect systemic inflammation. Screening for proteinuria and albuminuria allows identification of patients at higher risk of kidney disease and other adverse outcomes. Fanconi syndrome, which has been associated with tenofovir use, is associated with severe tubular proteinuria, and several low molecular weight proteins, including retinol-binding protein, β2-microglobulin, and neutrophil gelatinase-associated lipocalin have been studied as markers of tubular dysfunction. Studies have reported a high prevalence of subclinical proximal tubular dysfunction in patients receiving antiretroviral therapy.

SUMMARY

Future studies are needed to determine the optimal biomarkers for the detection and monitoring of renal disease in HIV.

Cystatin C, albuminuria, and 5-year all-cause mortality in HIV-infected persons

BACKGROUND

Compared with controls, human immunodeficiency virus (HIV)-infected persons have a greater prevalence of kidney disease, assessed according to high cystatin C level and albuminuria, but not according to creatinine level. However, the clinical importance of increased cystatin C level and albuminuria in the HIV-infected population has not been studied.

STUDY DESIGN

We conducted an observational cohort study to determine the association of kidney disease (measured according to 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.

PREDICTOR

Serum cystatin C and serum creatinine levels were used to estimate glomerular filtration rates (eGFR(SCysC) and eGFR(SCr), respectively). Albuminuria was defined as a positive urine dipstick result (≥ 1+) or urine albumin-creatinine ratio >30 mg/g.

OUTCOME

5-Year mortality.

RESULTS

At baseline, decreased kidney function (eGFR(SCysC) <60 mL/min/1.73 m(2)) or albuminuria was present in 28% of participants. After 5 years of follow-up, mortality was 48% in those with both eGFR(SCysC) < 60 mL/min/1.73 m(2) and albuminuria, 23% in those with eGFR(SCysC) < 60 mL/min/1.73 m(2) 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 marker levels, eGFR(SCysC) < 60 mL/min/1.73 m(2) and albuminuria were associated with a nearly 2-fold increase in mortality, whereas eGFR(SCr) < 60 mL/min/1.73 m(2) did not appear to have a substantial association with mortality. Together, eGFR(SCysC) <60 mL/min/1.73 m(2) and albuminuria accounted for 17% of the population-level attributable risk of mortality.

LIMITATIONS

Vital status was unknown in 261 participants from the original cohort.

CONCLUSIONS

Kidney disease marked by albuminuria or increased cystatin C level 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.

Analysis of biomarker data: logs, odds ratios, and receiver operating characteristic curves

PURPOSE OF REVIEW

We discuss two data analysis issues for studies that use binary clinical outcomes (whether or not an event occurred): the choice of an appropriate scale and transformation when biomarkers are evaluated as explanatory factors in logistic regression and assessing the ability of biomarkers to improve prediction accuracy for event risk.

RECENT FINDINGS

Biomarkers with skewed distributions should be transformed before they are included as continuous covariates in logistic regression models. The utility of new biomarkers may be assessed by measuring the improvement in predicting event risk after adding the biomarkers to an existing model. The area under the receiver operating characteristic (ROC) curve (C-statistic) is often cited; it was developed for a different purpose, however, and may not address the clinically relevant questions. Measures of risk reclassification and risk prediction accuracy may be more appropriate.

SUMMARY

The appropriate analysis of biomarkers depends on the research question. Odds ratios obtained from logistic regression describe associations of biomarkers with clinical events; failure to accurately transform the markers, however, may result in misleading estimates. Although the C-statistic is often used to assess the ability of new biomarkers to improve the prediction of event risk, other measures may be more suitable.

Randomized comparison of renal effects, efficacy, and safety with once-daily abacavir/lamivudine versus tenofovir/emtricitabine, administered with efavirenz, in antiretroviral-naive, HIV-1-infected adults: 48-week results from the ASSERT study

BACKGROUND

Abacavir/lamivudine and tenofovir/emtricitabine fixed-dose combinations are commonly used first-line antiretroviral therapies, yet few studies have comprehensively compared their safety profiles.

METHODS

Forty-eight-week data are presented from this multicenter, randomized, open-label study comparing the safety profiles of abacavir/lamivudine and tenofovir/emtricitabine, both administered with efavirenz, in HLA-B*5701-negative HIV-1-infected adults.

RESULTS

Three hundred eighty-five subjects were enrolled in the study. The overall rate of withdrawal was high (28%). Changes in estimated glomerular filtration rate from baseline were similar between arms [difference 0.953 mL.min.1.73 m (95% confidence interval: -1.445 to 3.351), P = 0.435]. Urinary excretion of retinol-binding protein and beta-2 microglobulin increased significantly more in the tenofovir/emtricitabine arm (+50%; +24%) compared with the abacavir/lamivudine arm (no change; -47%) (P < 0.0001). A lower proportion achieved viral load <50 copies per milliliter in the abacavir/lamivudine arm (114 of 192, 59%) compared with the tenofovir/emtricitabine arm (137 of 193, 71%) [difference 11.6% (95% confidence interval: 2.2 to 21.1)]. The overall virological failure rate was low. The adverse event rate was similar between arms (except drug hypersensitivity, reported more in the abacavir/lamivudine arm).

CONCLUSIONS

The study showed no difference in estimated glomerular filtration rate between the arms, however, increases in markers of tubular dysfunction were observed in the tenofovir/emtricitabine arm, the long-term consequence of which is unclear. A significant difference in efficacy favoring tenofovir/emtricitabine was observed.

Recent developments in HIV-related kidney disease

Although kidney disease has been a recognized complication of HIV infection since the beginning of the HIV epidemic, its epidemiology, underlying causes and treatment have evolved in developed countries where HAART has been widely available. HIV-associated nephropathy and HIV immune complex-mediated kidney disease were the prominent renal diagnoses in the earlier period of the HIV epidemic. While HIV immune complex-mediated kidney disease remains a common finding among HIV-infected individuals with kidney disease, the incidence of HIV-associated nephropathy has been diminishing in developed countries. The role of the metabolic effects of long-term HAART exposure and nephrotoxicity of certain antiretroviral medications on the development and progression of chronic kidney disease is now of increasing concern. The long-term clinical implications of acute kidney injury among HIV-infected persons are increasingly recognized. Kidney disease in HIV-infected persons continues to be a major risk factor for morbidity and mortality in this patient population; therefore, early recognition and treatment of kidney disease are imperative in lessening the impact of kidney disease on the health of HIV-infected individuals. This review focuses on recent developments and ongoing challenges in the understanding, diagnosis and management of HIV-related kidney disease.

Markers of inflammation, coagulation, and renal function are elevated in adults with HIV infection

BACKGROUND

Human immunodeficiency virus (HIV) replication and immune activation may increase inflammation and coagulation biomarkers. Limited data exist comparing such biomarkers in persons with and without HIV infection.

METHODS

For persons 45-76 years of age, levels of high-sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, D-dimer, and cystatin C were compared in 494 HIV-infected individuals in the Strategies for Management of Anti-Retroviral Therapy (SMART) study and 5386 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) study. For persons 33-44 years of age, hsCRP and IL-6 levels were compared in 287 participants in the SMART study and 3231 participants in the Coronary Artery Development in Young Adults (CARDIA) study.

RESULTS

hsCRP and IL-6 levels were 55% (P < . 001) and 62 (P < . 001) higher among HIV-infected participants than among CARDIA study participants. Compared with levels noted in MESA study participants, hsCRP, IL-6, D-dimer, and cystatin C levels were 50%, 152%, 94%, and 27% higher, respectively (P < . 001, for each), among HIV-infected participants. HIV-infected participants receiving antiretroviral therapy who had HIV RNA levels 400 copies/mL had levels higher (by 21% to 60%) (P < . 001) than those in the general population, for all biomarkers.

CONCLUSIONS

hsCRP, IL-6, D-dimer, and cystatin C levels are elevated in persons with HIV infection and remain so even after HIV RNA levels are suppressed with antiretroviral therapy. Additional research is needed on the pathophysiology of HIV-induced activation of inflammatory and coagulation pathways, to guide potential interventions.

HIV and the Kidney

Direct effects of HIV-1 infection on the kidney combine with immune and genetic factors, comorbidities, coinfections, and medication toxicities to induce a spectrum of kidney disorders in HIV disease. The most dramatic of these, HIV-associated nephropathy (HIVAN), emerges almost exclusively in persons of African descent and is associated with rapid progression to end-stage renal disease in the absence of antiretroviral therapy (ART). ART modifies the natural history of HIVAN, but the renal benefits of ART may not be limited to HIVAN. ART is often under prescribed or incorrectly dosed in persons with kidney disease. Vigilant attention to renal function and an understanding of the complex associations involving the kidneys are necessary for optimal care of these patients.

HIV and CKD epidemiology

Nephrologists can serve many important functions for HIV-infected patients, including identifying risks for developing kidney disease, detecting and diagnosing kidney disease, distinguishing antiretroviral-induced kidney injury from kidney disease in the setting of antiretroviral therapy, comanaging the clinical course and complications of CKD, and preparing patients for dialysis and/or transplantation. The epidemiology of kidney disease in HIV informs us for these functions by describing the natural history of disease, its frequent occurrence in high-risk communities, and its potential causes. Risk factors that drive CKD in HIV are black race, hypertension, diabetes, HIV viral replication with low CD4 cell counts, high viral load or acquired immune deficiency syndrome-defining conditions, and antiretroviral agents with nephrotoxic potential. The prevalence of these risk factors in any population determines the magnitude of the problem, which can range from as low as 2% to as high as 30%. Recent research focuses on kidney health in HIV. Important links between HIV viral replication and glomerular filtration rate, even in patients with normal kidney function, are now being reported. A review of these data provides the foundation for a better understanding of kidney disease and, hopefully, better treatment for patients with HIV.

T-cell dysfunction in HIV-1 infection: targeting the inhibitors

Since AIDS emerged almost three decades ago, there have been considerable advances in the field of antiretroviral chemotherapy for those chronically infected with HIV-1. However, this therapy is noncurative and as our understanding of HIV-1 immunopathogenesis increases, it is becoming apparent that further therapeutic interventions are required to reverse the devastating effects of HIV-1 infection worldwide. While viral clearance remains the principle goal of HIV-1 treatment, this article describes immunotherapeutic options that target the immunological effects of the virus, to reduce its presence in the body and counteract viral-induced T-cell dysfunction and inhibition. Such approaches may augment existing antiretroviral therapy to overturn virus-induced T-cell anergy in the infected host, improving levels of immune control that reduce viremia and decrease the rate of transmission.

The treatment of HIV-associated nephropathy

Antiretroviral therapy (ART) preserves kidney function in patients with human immunodeficiency virus (HIV)-associated nephropathy (HIVAN). Emerging data also document substantial renal benefits of ART in the general HIV-infected population, which is associated in part with suppression of HIV-1 viral replication. The extent to which the response to ART differs in persons with HIVAN compared with those with other HIV-associated kidney disorders is unknown. Beneficial effects of corticosteroids and angiotensin-converting enzyme inhibitors on kidney function also are suggested by retrospective cohort studies and uncontrolled trials of patients with HIVAN. Underexposure to ART or inadequate ART dosing in HIV-infected patients with CKD may curtail the optimal benefits that may be derived from this therapy.

Screening for chronic kidney disease in HIV-infected patients

With improved survival afforded by highly active antiretroviral therapy (HAART), CKD has emerged as one of the primary comorbid conditions affecting HIV-infected individuals. Although CKD in HIV-infected individuals is classically thought of as a consequence of advanced HIV infection such as in the case of HIV-associated nephropathy, several factors likely contribute to the development CKD in HIV infection. These factors include genetic predisposition, age-related decline in kidney function, HAART-related metabolic changes, exposure to multiple nephrotoxic medications, and concurrent conditions such as hepatitis C or illicit drug use. Similar to the general population, proteinuria and impaired kidney function are associated with faster progression to acquired immune deficiency syndrome and death. Given the prevalence and impact of kidney disease on the course of HIV infection and its management, current guidelines recommend screening all HIV-infected individuals for kidney disease. This review focuses on the current guidelines for kidney disease screening and discusses traditional as well as promising strategies for detecting CKD in this vulnerable population.

Ignoring the obvious missing piece of chronic kidney disease in HIV: cigarette smoking

The impact of tobacco use on the development of chronic kidney disease (CKD) in people living with HIV (PLWH) has been overlooked, despite remarkably higher rates of smoking in these individuals. The authors examined the association between smoking and the risk of CKD in a case-controlled study that included 75 PLWH with CKD and 461 PLWH consecutively admitted to the hospital for other causes. Significant differences in gender, race/ethnicity, hypertension, hepatitis B, CD4 cell counts, and smoking between cases and controls were reported, suggesting that these variables may be risk factors for CKD. In logistic regression analyses, smoking (OR=1.97, p=.003), hypertension (OR=2), and African ancestry, particularly for Black Caribbeans (OR=2.6), were independent factors associated with CKD. Moreover, the results pointed to a dose-response relationship between packs smoked per day and CKD. Smoking was reported to contribute a significant risk for CKD in these subjects.

Human immunodeficiency virus in an aging population, a complication of success

The proportion of human immunodeficiency virus (HIV)-infected patients aged 50 and older has greatly increased since the beginning of the epidemic, particularly since 1996, when combination antiretroviral therapy became available. By 2015, 50% of HIV-infected individuals in the United States are likely to be aged 50 and older. The rate of progression of untreated HIV disease, response to therapy, and complicating effects of comorbidities differ in older and younger patients. Older untreated patients with HIV demonstrate faster rates of CD4(+) cell loss and more rapid progression to acquired immunodeficiency syndrome (AIDS) and death than younger individuals. Synergistic deleterious effects of chronic immune activation on the course of HIV infection with the immune senescence of aging may promote this accelerated course. Despite the increasing prevalence in older patients and cost-effectiveness analyses that favor HIV testing, older patients are less likely to be routinely evaluated for HIV infection. Consequently, when diagnosed, older patients have more-advanced disease than do younger patients and, upon presentation with AIDS-defining conditions, are less likely to receive timely appropriate therapy. The treatment of older HIV-infected patients is complicated by preexisting comorbid conditions, including cardiovascular, hepatic, and metabolic complications, which in turn may be exacerbated by the effects of HIV infection per se, modest immunodeficiency (i.e., at CD4(+) counts >350 cells/microL), and the metabolic and other adverse effects of combination antiretroviral therapy. Nevertheless, older patients derive substantial benefit from combination antiretroviral therapy despite having less of an immunological response than expected given their adherence to therapy and excellent virological responses.

Proteinuria, creatinine clearance, and immune activation in antiretroviral-naive HIV-infected subjects

Because both renal disease and immune activation predict progression to acquired immunodeficiency syndrome (AIDS), we evaluated the associations between proteinuria>or=1+, as determined by dipstick analysis (7 [7%] of 1012 subjects); creatinine clearance of <90 mL/min (195 [18%] of 1071 subjects); and percentages of peripheral activated CD8 cells (CD8+CD38+HLA-DR+ cells) in antiretroviral-naive, human immunodeficiency virus (HIV)-infected subjects who were enrolled in AIDS Clinical Trials Group studies 384 and A5095. Proteinuria, but not creatinine clearance, was associated with higher percentages of CD8+CD38+HLA-DR+ cells (55% vs. 50%; P=.01), with even more pronounced differences noted among men and among blacks and Hispanics. Proteinuria may be a surrogate measurement of greater immune activation in HIV-infected patients initiating antiretroviral therapy.

HIV viremia and changes in kidney function

OBJECTIVE

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.

DESIGN

A prospective cohort.

METHODS

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 x cysC(-1.19).

RESULTS

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 < or = 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.

CONCLUSION

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.

Cardiovascular, renal and liver events associated with human immunodeficiency virus type 1 infection and antiretroviral therapy

The first 15 years of the human immunodeficiency virus type 1 epidemic was characterized by patients progressing to clinical acquired immunodeficiency syndrome and death. The availability of potent antiretrovirals led to the recognition of unique adverse events associated with select drugs. More recent data suggest that end-organ damage may be associated with ongoing viremia. Further understanding of the potential role different drugs and the virus itself has on various organs can enhance the clinician's ability to manage patients in the clinic.