A chronic kidney disease risk score to determine tenofovir safety in a prospective cohort of HIV-positive male veterans

HIV and CKD in the Tenofovir Era: A Prospective Parallel-Group Cohort Study From Tanzania

Rationale & Objective

Longitudinal research on chronic kidney disease (CKD) in sub-Saharan Africa is sparse, especially among people living with HIV (PLWH). We evaluated the incidence of CKD among PLWH compared with HIV-uninfected controls in Tanzania.

Study Design

Prospective cohort study.

Setting & Participants

A total of 495 newly diagnosed PLWH who initiated antiretroviral therapy (ART) and 505 HIV-uninfected adults enrolled from public HIV clinics and followed from 2016-2021. The control group was recruited from HIV treatment partners from the same HIV clinics.

Exposures

Untreated HIV (at baseline), ART, sociodemographic information, health behaviors, hypertension, and diabetes.

Outcomes

Incident CKD, defined as a follow-up estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2 with ≥25% reduction from baseline; annual eGFR change; incident albuminuria; 3-year all-cause mortality.

Analytical Approach

Multivariable Poisson and linear regression determined the association between HIV and other factors with a baseline prevalent reduced eGFR and albuminuria, incident CKD and albuminuria, and annual eGFR change. Cox hazard regression assessed the association between baseline CKD and mortality.

Results

Median age was 35 years and 67.5% were women. There were 101 incident CKD cases, 71 among PLWH and 30 among HIV-uninfected participants, equivalent to a CKD incidence of 57.9 per 1,000 person-years (95% CI, 44.4-71.4) and 26.2 per 1,000 person-years (95% CI, 16.8-35.5), respectively. PLWH had a more rapid eGFR decline (-6.65 vs -2.61 mL/min/1.73 m2 per year). Female sex and older age were positively associated with incident CKD. Albuminuria incidence did not differ by HIV status. PLWH with albuminuria at baseline had higher mortality (HR, 2.13; 95% CI, 1.08-4.21).

Limitations

As an observational cohort study, there was no comparison group of HIV-positive participants on a nontenofovir disoproxil fumarate-based ART regimen.

Conclusions

PLWH receiving tenofovir disoproxil fumarate-based ART had a very high incidence of CKD and rapid eGFR decline. Conversely, albuminuria stabilized with ART use. Expanding access to less-nephrotoxic ART, such as tenofovir alafenamide, is urgently needed throughout sub-Saharan Africa.

Update in Human Immunodeficiency Virus and Aging

Effective and consistent antiretroviral therapy has enabled people with human immunodeficiency virus (HIV) (PWH) to survive longer than previously encountered earlier in the epidemic. Consequently, PWH are subject to the struggles and clinical conditions typically associated with aging. However, the aging process in PWH is not the same as for those who do not have HIV. There is a complex interplay of molecular, microbiologic, and pharmacologic factors that leads to accelerated aging in PWH; this leads to increased risk for certain age-related comorbidities requiring greater vigilance and interventions in routine care.

Associations between female birth sex and risk of chronic kidney disease development among people with HIV in the USA: A longitudinal, multicentre, cohort study

Background

Women represent a meaningful proportion of new HIV diagnoses, with Black women comprising 58% of new diagnoses among women. As HIV infection also increases risk of chronic kidney disease (CKD), understanding CKD risk among women with HIV (WWH), particularly Black women, is critical.

Methods

In this longitudinal cohort study of people with HIV (PWH) enrolled in CFAR Network of Integrated Clinical Systems (CNICS), a multicentre study comprised of eight academic medical centres across the United States from Jan 01, 1996 and Nov 01, 2019, adult PWH were excluded if they had ≤2 serum creatinine measurements, developed CKD prior to enrollment, or identified as intersex or transgendered, leaving a final cohort of 33,998 PWH. The outcome was CKD development, defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1·73 m2 calculated using the CKD-EPI equation, for ≥90 days with no intervening higher values.

Findings

Adjusting for demographic and clinical characteristics, WWH were 61% more likely to develop CKD than men (adjusted hazard ratio [aHR]: 1·61, 95% CI: 1·46-1·78, p<0·001). This difference persisted after further adjustment for APOL1 risk variants (aHR female sex: 1·92, 95% CI: 1·63-2·26, p<0·001) and substance abuse (aHR female sex: 1·70, 95% CI: 1·54-1·87, p<0·001).

Interpretation

WWH experienced increased risk of CKD. Given disparities in care among patients with end-stage kidney disease, efforts to engage WWH in nephrology care to improve chronic disease management are critical.

Funding

US National Institutes of Health.

Clinical Characteristics and Outcomes of Chronic Kidney Disease in People Living with HIV in a Resource-Limited Center of Central China

Clinical management and optimal treatment are essential to improving outcomes for people living with HIV (PLWH). We assessed trends and outcomes of chronic kidney disease (CKD) in PLWH in a resource-limited center of central China. All PLWH who were followed up in a tertiary referral center in Wuhan, China, from July 2016 to June 2021 were evaluated. CKD was defined as glomerular filtration rate (GFR) <60 mL/min/1.73 m² during two consecutive measurements 3 months apart. Baseline characteristics of the participants were extracted from the hospital medical records. The prevalence rate and associated risk factors of CKD were analyzed. A total of 863 PLWH with normal kidney function at baseline were analyzed. The median age was 33 (interquartile ranges: 26-49) years, and 778 (90.2%) were male and 85 (9.8%) were female. Among them, 50 (5.8%) had their GFR falling below 60 mL/min/1.73 m² after a median of 54 months. Adjusted multivariate logistic regression revealed older age [adjusted odds ratio (aOR) = 1.04, 95% confidence interval (95% CI): 1.01-1.07], female sex (aOR = 3.17, 95% CI: 1.14-8.84), lower body weight (aOR = 0.95, 95% CI: 0.91-1.00), lower hemoglobin (aOR = 3.54, 95% CI: 1.51-8.30), longer duration of antiretroviral therapy exposure (aOR = 1.02, 95% CI: 1.00-1.04), and a baseline GFR between 60 and 90 mL/min/1.73 m² (aOR = 3.89, 95% CI: 1.21-12.46) were associated with the development of CKD. Our findings showed that CKD is not infrequent in PLWH with a combination of traditional and HIV-specific risk factors for kidney disease, highlighting the suboptimal monitoring and treatment options of CKD in PLWH in resource-limited settings. Scalable monitoring strategy to improve care for this population is warranted.

Chronic Kidney Disease in a Large National Human Immunodeficiency Virus Treatment Program

Tenofovir disoproxil fumarate (TDF) is associated with a risk of chronic kidney disease (CKD), especially in Asian populations. Data from the Thai national health insurance system was used to assess CKD incidence in patients receiving antiretroviral therapy in real-world practice. We analyzed data from patients who initiated one of the following first-line regimens: zidovudine + lamivudine + nevirapine (AZT + 3TC + NVP); zidovudine + lamivudine + efavirenz (AZT + 3TC + EFV); tenofovir + lamivudine + nevirapine (TDF + 3TC + NVP); tenofovir + lamivudine/emtricitabine + efavirenz (TDF + 3TC/FTC + EFV); and tenofovir +lamivudine +lopinavir/ritonavir (TDF + 3TC + LPV/r). CKD was defined as glomerular filtration rate <60 mL/min/1.73 m2 for >3 months, or a confirmed 2010 WHO diagnosis (ICD-10 code N183, N184, or N185). Death competing risk survival regression models were used. Among 27,313 participants, with a median age of 36.8 years and median follow-up of 2.3 years, 245 patients (0.9%) were diagnosed with CKD (incidence 3.2 per 1000 patient-years; 95% CI 2.8−3.6). Compared with patients receiving AZT + 3TC + NVP, the risk of CKD measured by adjusted sub-distribution hazard ratio (aSHR) was 6.5 (95% CI 3.9−11.1) in patients on TDF + 3TC + LPV/r, 3.8 (95% CI 2.3−6.0) in TDF + 3TC + NVP, and 1.6 (95% CI 1.2−2.3) in TDF + 3TC/FTC + EFV. Among patients receiving TDF, compared with those receiving TDF + 3TC/FTC + EFV, the aSHR was 4.0 (95% CI 2.3−6.8) in TDF + 3TC + LPV/r and 2.3 (95% CI 1.4−3.6) in TDF + 3TC + NVP. TDF was associated with an increased risk of CKD, especially when combined with LPV/r or NVP.

Incidence of impaired kidney function among people with HIV: a systematic review and meta-analysis

BACKGROUND

In the era of combination antiretroviral therapy (ART), the incidence, manifestations and severity of kidney diseases have dramatically changed in people living with HIV (PLWH). Little is known about the incidence of impaired kidney function (IKF) measured by serum creatine-based estimated glomerular filtration rate (eGFR) in PLWH.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Ovid, Medline, Embase and Web of Science for studies published before May 7th, 2021, with estimates of incidence of IKF among PLWH. We independently reviewed each study for quality by using the Newcastle-Ottawa scale. The incidence and 95% confidence intervals (CIs) were calculated using random-effects model.

RESULTS

Sixty out of 3797 identifiable studies were eligible for the meta-analysis. A total of 19 definitions of IKF were described and categorized into three types: the threshold of eGFR, an absolute or percent decrease in eGFR, and certain eGFR threshold combined with decrement in eGFR. The eGFR< 60 ml/min/1.73m2 was the most widely used definition or criterion for IKF, by which the pooled incidence rate of IKF was 12.50 (95%CI: 9.00-17.36) per 1000 person years (PYs). The second most-studied outcome was a > 25% decrease in eGFR, followed by eGFR< 90 ml/min/1.73m2, eGFR< 30 ml/min/1.73m2 and a combination of eGFR threshold plus decreased eGFR. The reported incidence rates of IKF differ widely by different definitions of IKF. The highest pooled incidence was observed for those with > 25% decrease in eGFR, while the lowest was observed in those with eGFR < 30 ml/min/1.73m2. Substantial heterogeneity was identified across most estimates.

CONCLUSION

Our study provides a comprehensive summary of eGFR-based definitions and incidence rates of IKF in PLWH, not only promoting our understanding of IKF, but also underscoring needs for a concerted action to unify definitions and outcomes of IKF and their applications in AIDS care.

The Impact of Immunosuppression on Chronic Kidney Disease in People Living With Human Immunodeficiency Virus: The D:A:D Study

BACKGROUND

Relations between different measures of human immunodeficiency virus-related immunosuppression and chronic kidney disease (CKD) remain unknown.

METHODS

Immunosuppression measures included baseline, current, time-lagged and nadir CD4, years and percentage of follow-up (%FU) with CD4 ≤200 cells/μL, and CD4 recovery. CKD was defined as confirmed estimated glomerular filtration rate <60 mL/minute/1.73 m2.

RESULTS

Of 33 791 persons, 2226 developed CKD. Univariably, all immunosuppression measures predicted CKD. Multivariably, the strongest predictor was %FU CD4 ≤200 cells/μL (0 vs >25%; incidence rate ratio [IRR], 0.77 [95% confidence interval [CI], .68-.88]), with highest effect in those at low D:A:D CKD risk (IRR, 0.45 [95% CI, .24-.80]) vs 0.80 [95% CI, .70-.93]).

CONCLUSIONS

Longer immunosuppression duration most strongly predicts CKD and affects persons at low CKD risk more.

Validation of the D: A: D Chronic Kidney Disease Risk Score Model Among People Living With HIV in the Asia-Pacific

BACKGROUND

We validated the Data collection on Adverse events of anti-HIV Drugs (D:A:D) full-risk and short-risk score models for chronic kidney disease (CKD) in the Asian HIV cohorts.

SETTINGS

A validation study among people living with HIV (PLHIV) aged ≥18 years among the cohorts in the Asia-Pacific region.

METHODS

PLHIV with a baseline estimated glomerular filtration rate > 60 mL/min/1.73 m were included for validation of the D:A:D CKD full version and short version without cardiovascular risk factors. Those with <3 estimated glomerular filtration rate measurements from baseline or previous exposure to potentially nephrotoxic antiretrovirals were excluded. Kaplan-Meier methods were used to estimate the probability of CKD development. The area under the receiver operating characteristics was also used to validate the risk score.

RESULTS

We included 5701 participants in full model {median 8.1 [interquartile range (IQR) 4.8-10.9] years follow-up} and 9791 in short model validation [median 4.9 (IQR 2.5-7.3) years follow-up]. The crude incidence rate of CKD was 8.1 [95% confidence interval (CI): 7.3 to 8.9] per 1000 person-years in the full model cohort and 10.5 (95% CI: 9.6 to 11.4) per 1000 person-years in the short model cohort. The progression rates for CKD at 10 years in the full model cohort were 2.7%, 8.9%, and 26.1% for low-risk, medium-risk, and high-risk groups, and 3.5%, 11.7%, and 32.4% in the short model cohort. The area under the receiver operating characteristics for the full-risk and short-risk score was 0.81 (95% CI: 0.79 to 0.83) and 0.83 (95% CI: 0.81 to 0.85), respectively.

CONCLUSION

The D:A:D CKD full-risk and short-risk score performed well in predicting CKD events among Asian PLHIV. These risk prediction models may be useful to assist clinicians in identifying individuals at high risk of developing CKD.

Validation of the D:A:D chronic kidney disease risk score in people living with HIV: the IeDEA West Africa Cohort Collaboration

OBJECTIVES

A risk score for long-term prediction of chronic kidney disease (CKD) in people living with HIV (PLHIV) has been developed using data from the D:A:D cohort. We assessed the performance of the D:A:D risk score in a cohort of PLHIV in West Africa.

METHODS

Data from PLHIV starting antiretroviral treatment in four clinics in Burkina Faso, Côte d'Ivoire and Togo participating in the IeDEA West Africa collaboration were analysed. CKD was defined as two consecutive estimated glomerular filtration rates (eGFRs) of ≤ 60 mL/min/1.73 m² . The D:A:D score (short version) was calculated using age, gender, nadir CD4 and baseline eGFR and was categorized into low, medium, and high-risk groups.

RESULTS

In 14 930 participants (70% female, median age = 38 years; median nadir CD4 count = 183 cells/µL) followed for a median duration of 5.7 years, 660 (4.4%) progressed to CKD, with an incidence [95% confidence interval (CI)] of 7.8 (7.2-8.4) per 1000 person-years (PY). CKD incidence rates were 2.4 (2.0-2.8), 8.1 (6.8-9.6) and, 30.9 (28.0-34.1) per 1000 PY in the low-, medium- and high-risk groups, respectively. In the high-risk group, 14.7% (95% CI: 13.3; 16.3) had progressed to CKD at 5 years. Discrimination was good [C-statistics = 0.81 (0.79-0.83)]. In all, 79.4% of people who progressed to CKD were classified in the medium- to high-risk group at baseline (sensitivity) and 66.5% of people classified in the low risk group at baseline did not progress to CKD (specificity).

CONCLUSIONS

These findings confirm the validity of the D:A:D score in identifying individuals at risk of developing CKD who could benefit from enhanced kidney monitoring in West African HIV clinics.

Association of tenofovir disoproxil fumarate exposure with chronic kidney disease and osteoporotic fracture in US veterans with HIV

BACKGROUND

Tenofovir disoproxil fumarate (TDF)-based regimens have been associated with impaired kidney function and loss of bone mineral density among patients living with HIV (PLWH). We assess the association between TDF exposure and the odds of chronic kidney disease (CKD) and osteoporotic fracture in HIV patients.

METHODS

Demographics, administrative claims, and pharmacy dispensation were extracted from the Veterans Affairs Informatics and Computing Infrastructure (VINCI). Patients were categorized based on TDF utilization. Incidence rates for patients exposed and unexposed to TDF were calculated per 1000 patient-years (PYs). Logistic regression was used to calculate the odds of outcome after adjusting for baseline and clinical characteristics.

RESULTS

The sample included 4,630 PLWH who were currently exposed to TDF and 1,181 who were never exposed to TDF for the CKD analyses. For fracture analyses, the sample included 6,883 PLWH who were currently exposed to TDF and 1,951 who were never exposed to TDF. In adjusted models, current TDF exposure was associated with increased odds of CKD compared to never having been exposed (OR: 1.48, 95% CI: 1.18-1.85). Odds of fracture were 2.32 times higher for patients who were currently on a TDF regimen (OR: 2.32, 95% CI: 1.58-3.42) compared to those who had never been exposed to TDF in adjusted models.

CONCLUSIONS

In a large cohort of US veterans with HIV, current exposure to TDF was associated with a 48% higher odds of CKD and a greater than two-fold increase in the odds of osteoporotic fracture.

Influence of hepatitis C virus co-infection and hepatitis C virus treatment on risk of chronic kidney disease in HIV-positive persons

BACKGROUND

Hepatitis C virus (HCV) infection has been associated with increased risk of chronic kidney disease (CKD). We investigated the impact of HCV cure on CKD in HIV-positive persons in the EuroSIDA study.

METHODS

HIV-positive persons with known HCV status and at least three serum creatinine measurements after 1/1/2004 were compared based on time-updated HCV-RNA and HCV treatment: anti-HCV-negative, spontaneously cleared HCV, chronic untreated HCV, successfully treated HCV, and HCV-RNA positive after HCV treatment. Poisson regression compared incidence rates of CKD [confirmed (>3 months apart) eGFR <60 ml/min per 1.73 m] between HCV strata.

RESULTS

Fourteen thousand, seven hundred and fifty-four persons were included; at baseline 9273 (62.9%) were HCV-Ab negative, 696 (4.7%) spontaneous clearers, 3021 (20.5%) chronically infected, 922 (6.2%) successfully treated and 842 (5.7%) HCV-RNA positive after treatment. During 115 335 person-years of follow-up (PYFU), 1128 (7.6%) developed CKD; crude incidence 9.8/1000 PYFU (95% CI 9.2-10.4). After adjustment, persons anti-HCV negative [adjusted incidence rate ratio (aIRR) 0.59; 95% CI 0.46-0.75] and spontaneous clearers (aIRR 0.67; 95% CI 0.47-0.97) had significantly lower rates of CKD compared with those cured whereas persons chronically infected (aIRR 0.85; 95% CI 0.65-1.12) and HCV-RNA positive after treatment (aIRR 0.71; 95% CI 0.49-1.04) had similar rates. Analysis in those without F3/F4 liver fibrosis using a more rigorous definition of CKD showed similar results.

CONCLUSION

This large study found no evidence that successful HCV treatment reduced CKD incidence. Confounding by indication, where those with highest risk of CKD were prioritized for HCV treatment in the DAA era, may contribute to these findings.

Cohort-derived machine learning models for individual prediction of chronic kidney disease in people living with HIV: a prospective multicentre cohort study

BACKGROUND

It is unclear whether data-driven machine learning models, which are trained on large epidemiological cohorts, may improve prediction of co-morbidities in people living with HIV.

METHODS

In this proof-of-concept study, we included people living with HIV of the prospective Swiss HIV Cohort Study with a first estimated glomerular filtration rate (eGFR) >60 ml/min/1.73 m2 after January 1, 2002. Our primary outcome was chronic kidney disease (CKD) ─ defined as confirmed decrease in eGFR ≤60 ml/min/1.73 m2 over three months apart. We split the cohort data into a training set (80%), validation set (10%), and test set (10%) ─ stratified for CKD status and follow-up length.

RESULTS

Of 12,761 eligible individuals (median baseline eGFR, 103 ml/min/1.73 m2), 1,192 (9%) developed a CKD after a median of eight years. We used 64 static and 502 time-changing variables: Across prediction horizons and algorithms and in contrast to expert-based standard models, most machine learning models achieved state-of-the-art predictive performances with areas under the receiver operating characteristic curve and precision recall curve ranging from 0.926 to 0.996 and from 0.631 to 0.956, respectively.

CONCLUSIONS

In people living with HIV, we observed state-of-the-art performances in forecasting individual CKD onsets with different machine learning algorithms.

Optimizing antiretroviral regimens in chronic kidney disease

PURPOSE OF REVIEW

To identify recent data that inform the management of individuals with HIV and chronic kidney disease.

RECENT FINDINGS

Several nonnucleoside reverse transcriptase, protease, and integrase strand transfer inhibitors inhibit tubular creatinine secretion resulting in stable reductions in creatinine clearance of 5-20 ml/min in the absence of other manifestations of kidney injury. Progressive renal tubular dysfunction is observed with tenofovir disoproxil fumarate in clinical trials, and more rapid decline in estimated glomerular filtration rate in cohort studies of tenofovir disoproxil fumarate and atazanavir, with stabilization, improvement or recovery of kidney function upon discontinuation. Results from clinical trials of tenofovir alafenamide (TAF) in individuals with chronic kidney disease suggest that TAF is well tolerated in those with mild to moderate renal impairment (creatinine clearance >30 ml/min) but results in very high tenofovir exposures in those on haemodialysis.

SUMMARY

Standard antiretroviral regimens remain appropriate for individuals with normal and/or stable, mildly impaired kidney function. In those with chronic kidney disease or progressive decline in estimated glomerular filtration rate, antiretrovirals with nephrotoxic potential should be avoided or discontinued. Although TAF provides a tenofovir formulation for individuals with impaired kidney function, TAF is best avoided in those with severe or end-stage kidney disease.

Validation of the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) chronic kidney disease risk score in HIV-infected patients in the USA

Objectives

The aim of the study was to assess the validity of an easy‐to‐calculate chronic kidney disease (CKD) risk score developed by the Data Collection on Adverse Events of Anti‐HIV Drugs (D:A:D) group in a longitudinal observational study of people living with HIV (PLWH) in the USA.

Methods

PLWH (2002–2016) without prior exposure to potentially nephrotoxic antiretroviral agents and with at least three estimated glomerular filtration rate (eGFR) test results were identified in the Observational Pharmaco‐Epidemiology Research and Analysis (OPERA^®) cohort. Three samples were drawn independently using the same eligibility criteria but each using a different eGFR equation, specifically the Cockcroft–Gault (C‐G), Modification of Diet in Renal Disease (MDRD) or Chronic Kidney Disease Epidemiology Collaboration (CKD‐EPI) eGFR estimation method. Full and short D:A:D risk scores were applied. CKD was defined as a confirmed decrease in eGFR to < 60 mL/min/1.73 m² (stages 3–5). Poisson models estimated the association between CKD incidence and a one‐point increase in the continuous risk score. The incidence rate ratio (IRR), adjusted IRR (aIRR), and Harrell's discrimination statistic were used to assess validity.

Results

There were 19 444, 22 727 and 22 748 PLWH in the OPERA C‐G, CKD‐EPI and MDRD samples, respectively. The median (minimum–maximum) follow‐up duration was 6.1 (0.3–9.1) years in the D:A:D cohort and ranged from 3.2 to 3.5 (0.2–15.5) years in the OPERA validation samples. The observation time for the majority of PLWH in the D:A:D cohort began prior to 2006, in stark contrast to the OPERA validation samples, where the majority of PLWH were observed after 2011. The CKD incidence ranged from 7.3 per 1000 person‐years [95% confidence interval (CI) 6.8, 7.9 per 1000 person‐years] in OPERA C‐G to 11.0 (95% CI 10.4, 11.6 per 1000 person‐years) in OPERA MDRD. In OPERA samples, IRRs by risk group and adjusted IRRs (full risk score) were similar to those in the D:A:D derivation cohort (adjusted IRR 1.3; 95% CI 1.3, 1.3). Harrell's c‐statistic ranged from 0.87 to 0.92 in the OPERA samples, comparable to that in the derivation cohort (0.92). Results for short scores were similar.

Conclusions

The findings support the validity of the D:A:D risk scoring method for assessing CKD (stages 3–5) probability in an exclusively USA‐based sample regardless of eGFR method.

Serious clinical events in HIV-positive persons with chronic kidney disease

OBJECTIVES

Predictors of chronic kidney disease (CKD) amongst HIV-positive persons are well established, but insights into the prognosis after CKD including the role of modifiable risk factors are limited.

DESIGN

Prospective cohort study.

METHODS

D:A:D participants developing CKD (confirmed, >3 months apart, eGFR ≤ 60 ml/min per 1.73 m or 25% eGFR decrease when eGFR ≤ 60 ml/min per 1.73 m) were followed to incident serious clinical events (SCE); end stage renal and liver disease (ESRL and ESLD), cardiovascular disease (CVD), AIDS-defining and non-AIDS-defining malignancies (NADM), other AIDS or death, 6 months after last visit or 1 February 2016. Poisson regression models considered associations between SCE and modifiable risk factors.

RESULTS

During 2.7 (IQR 1.1-5.1) years median follow-up 595 persons with CKD (24.1%) developed a SCE [incidence rate 68.9/1000 PYFU (95% confidence interval 63.4-74.4)] with 8.3% (6.9-9.0) estimated to experience any SCE at 1 year. The most common SCE was death (12.7%), followed by NADM (5.8%), CVD (5.6%), other AIDS (5.0%) and ESRD (2.9%). Crude SCE ratios were significantly higher in those with vs. without CKD, strongest for ESRD [65.9 (43.8-100.9)] and death [4.8 (4.3-5.3)]. Smoking was consistently associated with all CKD-related SCE. Diabetes predicted CVD, NADM and death, whereas dyslipidaemia was only significantly associated with CVD. Poor HIV-status predicted other AIDS and death, eGFR less than 30 ml/min per 1.73 m predicted CVD and death and low BMI predicted other AIDS and death.

CONCLUSION

In an era where many HIV-positive persons require less monitoring because of efficient antiretroviral treatment, persons with CKD carry a high burden of SCE. Several potentially modifiable risk factors play a central role for CKD-related morbidity and mortality.

ESRD patients coinfected with human immunodeficiency virus and Hepatitis C: Outcomes and management challenges

HIV infection is a major public health problem worldwide. Due to shared modes of acquisition, many HIV+ patients are coinfected with Hepatitis C. HIV/HCV coinfected patients have an increased burden of chronic kidney disease and are more likely to progress to end-stage renal disease. Dialysis survival is diminished in the coinfected population, even in the contemporary era. Kidney transplantation offers a survival benefit over remaining on dialysis; however, posttransplant outcomes are inferior compared to patients with HIV infection alone. Direct acting antiviral agents may offer an opportunity to improve patient survival, but there are significant drug-drug interactions involving the direct acting antiviral agents, antiretroviral therapy, and immunosuppression that the clinician should be aware of.

Predictors of chronic kidney disease and utility of risk prediction scores in HIV-positive individuals

OBJECTIVE

The current study aimed to validate existing risk prediction scores and identify predictors of chronic kidney disease (CKD) in the setting of HIV.

DESIGN AND METHODS

A retrospective cohort study of HIV-positive individuals (n = 748) with baseline estimated glomerular filtration rate (eGFR) more than 60 ml/min was conducted at the Alfred Hospital, Melbourne, Australia. Multivariable regression analysis was performed to determine factors associated with development of CKD, defined as two consecutive measurements of eGFR less than 60 ml/min. The performance of CKD risk scores proposed by the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) Study Group and Scherzer and colleagues were estimated by the area under the receiver operator curve (AUROC).

RESULTS

CKD developed in 37 individuals (5.0%), at a median of 4.7 (interquartile range 2.2, 6.2) years. Older age [odds ratio (OR) 3.03, 95% confidence interval (CI): 1.20, 7.65, P = 0.02] and lower baseline eGFR (OR 10.39, 95% CI: 4.73, 22.83, P < 0.001) were associated with the development of CKD. Neither current, nor cumulative tenofovir disoproxil fumarate (TDF) use was associated with progression to CKD [current TDF hazard ratio (HR) 1.05, 95% CI: 0.54, 2.07, P = 0.88; cumulative TDF HR 1.03, 95% CI: 0.86, 1.24, P = 0.75]. The short D:A:D and Scherzer scores were well calibrated, with the short D:A:D score demonstrating superior discrimination (short D:A:D AUROC 0.85, Scherzer AUROC 0.78, P = 0.02).

CONCLUSION

Older individuals and those with a lower baseline eGFR are at higher risk for CKD. Risk prediction tools may be useful in identifying those at greatest risk, who may benefit from aggressive management of risk factors.

Prevalence and risk factors of mild chronic renal failure in HIV-infected patients: influence of female gender and antiretroviral therapy

Background

In people living with HIV, much is known about chronic kidney disease, defined as a glomerular filtration rate under 60 mL/min. However, there is scarce data about prevalence and risk factors for milder impairment (60–89 mL/min).

Objective

The present study aims to assess the influence of sex, antiretroviral therapy, and classical risk factors on the occurrence of mild decreased renal function in a large Spanish cohort of HIV-infected patients.

Methods

Cross-sectional, single center study, including all adult HIV-1-infected patients under antiretroviral treatment with at least two serum creatinine measures during 2014, describing the occurrence of and the risk factors for mildly decreased renal function (eGFR by CKD-EPI creatinine equation of 60–89 mL/min).

Results

Among the 4337 patients included, the prevalence rate of mildly reduced renal function was 25%. Independent risk factors for this outcome were age older than 50 years (OR 3.03, 95% CI 2.58–3.55), female sex (OR 1.23, 95% CI 1.02–1.48), baseline hypertension (OR 1.57, 95% CI 1.25–1.97) or dyslipidemia (OR 1.48, 95% CI 1.17–1.87), virologic suppression (OR 1.88, 95% CI 1.39–2.53), and exposure to tenofovir disoproxil-fumarate (OR 1.67, 95% CI 1.33–2.08) or ritonavir-boosted protease-inhibitors (OR 1.19, 95% CI 1.03–1.39).

Conclusions

Females and patients over 50 seem to be more vulnerable to renal impairment. Potentially modifiable risk factors and exposure to tenofovir disoproxil-fumarate or ritonavir-boosted protease-inhibitors are present even in earlier stages of chronic kidney dysfunction. It remains to be determined whether early interventions including antiretroviral therapy changes (tenofovir alafenamide, cobicistat) or improving comorbidities management will improve the course of chronic kidney disease.

A Review of Long-Term Toxicity of Antiretroviral Treatment Regimens and Implications for an Aging Population

Human immunodeficiency virus (HIV) is a chronic infectious disease currently requiring lifelong antiretroviral therapy (ART). People living with HIV (PLWH) face an increased risk of comorbidities associated with aging, chronic HIV, and the toxicity arising from long-term ART. A literature review was conducted to identify the most recent evidence documenting toxicities associated with long-term ART, particularly among aging PLWH. In general, PLWH are at a greater risk of developing fractures, osteoporosis, renal and metabolic disorders, central nervous system disorders, cardiovascular disease, and liver disease. There remains limited evidence describing the economic burden of long-term ART. Overall, an aging HIV population treated with long-term ART presents a scenario in which the clinical, humanistic, and economic burden for healthcare systems will demand thoughtful policy solutions that preserve access to treatment. Newer treatment regimens with fewer drugs may mitigate some of the cumulative toxicity burden of long-term ART.

Funding: ViiV Healthcare.

Potential kidney toxicity from the antiviral drug tenofovir: new indications, new formulations, and a new prodrug

PURPOSE OF REVIEW

The antiviral agent tenofovir is highly effective for the treatment of HIV and hepatitis B virus infections, and the older prodrug tenofovir disoproxil fumarate (TDF) is also a component of daily preexposure prophylaxis (PrEP) to reduce the risk of HIV infection in high-risk populations. Although TDF is well tolerated, the potential for kidney and bone toxicity has important implications for public health given the large number of individuals exposed to TDF worldwide. This review summarizes the recent literature on kidney and bone health in individuals treated with TDF and the newer prodrug tenofovir alafenamide (TAF).

RECENT FINDINGS

Risk factors for TDF toxicity appear to be similar in patients treated for HIV or hepatitis B virus and in HIV-uninfected PrEP users, although drug-drug interactions are a more important concern in HIV-positive individuals. The risk of toxicity appears to be lower with TAF, but further studies are needed to confirm the safety of long-term use and to evaluate the efficacy of TAF-based PrEP.

SUMMARY

Nephrologists should be aware of the potential kidney and bone toxicity of TDF, as well as unique situations in which the newer prodrug TAF may contribute to kidney injury.

Kidney disease in the setting of HIV infection: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

HIV-positive individuals are at increased risk for kidney disease, including HIV-associated nephropathy, noncollapsing focal segmental glomerulosclerosis, immune-complex kidney disease, and comorbid kidney disease, as well as kidney injury resulting from prolonged exposure to antiretroviral therapy or from opportunistic infections. Clinical guidelines for kidney disease prevention and treatment in HIV-positive individuals are largely extrapolated from studies in the general population, and do not fully incorporate existing knowledge of the unique HIV-related pathways and genetic factors that contribute to the risk of kidney disease in this population. We convened an international panel of experts in nephrology, renal pathology, and infectious diseases to define the pathology of kidney disease in the setting of HIV infection; describe the role of genetics in the natural history, diagnosis, and treatment of kidney disease in HIV-positive individuals; characterize the renal risk-benefit of antiretroviral therapy for HIV treatment and prevention; and define best practices for the prevention and management of kidney disease in HIV-positive individuals.

Aging in HIV-Infected Subjects: A New Scenario and a New View

The prevalence of HIV-infected people aged 50 years or older is increasing rapidly; the proportion will increase from 28% to 73% in 2030. In addition, HIV-infected individuals may be more vulnerable to age-related condition. There is growing evidence that the prevalence of comorbidities and other age-related conditions (geriatric syndromes, functional or neurocognitive/mental problems, polypharmacy, and social difficulties) is higher in the HIV-infected population than in their uninfected counterparts. However, despite the potential impact of this situation on health care, little information exists about the optimal clinical management of older HIV-infected people. Here we examine the age-related conditions in older HIV-infected persons and address clinical management according to author expertise and published literature. Our aim is to advance the debate about the most appropriate management of this population, including less well-studied aspects, such as frequency of screening for psychological/mental and social and functional capabilities.

Antiretroviral therapy as a risk factor for chronic kidney disease: Results from traditional regression modeling and causal approach in a large observational study

Objective

We investigated whether patients receiving selected antiretroviral combinations had a higher risk of chronic kidney disease (CKD) using traditional regression modeling and a causal approach in a large prospective cohort.

Patients and methods

For the purpose of this study, we selected 6301 patients who (i) started their first antiretroviral regimen after 1^st January 2004, (ii) had at least one serum creatinine measurement within 6 months before ART initiation (study entry), and (iii) had at least two measurements after study entry. Baseline eGFR was defined from the last serum creatinine measurement before study entry. All eGFR values were calculated using the Modification of Diet and Renal Disease (MDRD) equation. Both traditional Cox proportional hazards model and Cox marginal structural models were applied. Distinct coding for antiretroviral therapy exposure were investigated as well as double robust estimators.

Results

Overall we showed that patients receiving tenofovir (TDF) with a ritonavir boosted protease inhibitor (rbPI) exhibited a higher risk of CKD compared with patients who received TDF with a non-nucleosidic reverse transcriptase inhibitor (NNRTI). Such an increased risk was observed considering both initial and current regimens. Our analysis revealed a clinician-driven switch away from TDF among persons experiencing a decline in renal function while receiving this drug.

Conclusion

Our results show that combination of TDF and boosted protease inhibitor is associated with a higher CKD risk than TDF and a NNRTI.

Kidney Disease in HIV: Moving beyond HIV-Associated Nephropathy

In developed countries, remarkable advances in antiretroviral therapy have transformed HIV infection into a chronic condition. As a result, HIV-associated nephropathy, the classic HIV-driven kidney lesion among individuals of African descent, has largely disappeared in these regions. However, HIV-positive blacks continue to have much higher rates of ESRD than HIV-positive whites, which could be attributed to the APOL1 renal risk variants. Additionally, HIV-positive individuals face adverse consequences beyond HIV itself, including traditional risk factors for CKD and nephrotoxic effects of antiretroviral therapy. Concerns for nephrotoxicity also extend to HIV-negative individuals using tenofovir disoproxil fumarate-based pre-exposure prophylaxis for the prevention of HIV infection. Therefore, CKD remains an important comorbid condition in the HIV-positive population and an emerging concern among HIV-negative persons receiving pre-exposure prophylaxis. With the improved longevity of HIV-positive individuals, a kidney transplant has become a viable option for many who have progressed to ESRD. Herein, we review the growing knowledge regarding the APOL1 renal risk variants in the context of HIV infection, antiretroviral therapy-related nephrotoxicity, and developments in kidney transplantation among HIV-positive individuals.

Predictors of estimated glomerular filtration rate progression, stabilization or improvement after chronic renal impairment in HIV-positive individuals

OBJECTIVES

The objectives of this analysis were to investigate predictors of progression, stabilization or improvement in estimated glomerular filtration rate (eGFR) after development of chronic renal impairment (CRI) in HIV-positive individuals.

DESIGN

Prospective observational study.

METHODS

The Data Collection on Adverse events of Anti-HIV Drugs (D:A:D) study participants progressing to CRI defined as confirmed, at least 3 months apart, and eGFR 70 ml/min per 1.73 m or less were included in the analysis. The median of all eGFRs measured 24-36 months post-CRI was compared with the median eGFR defining CRI, and changes were grouped into improvement (>+10 ml/min per 1.73 m), stabilization (-10 to +10 ml/min per 1.73 m) and progression (<-10 ml/min per 1.73 m). Adjusted polynomial regression models assessed odds of better eGFR outcomes after CRI, assuming that eGFR improvement is better than stabilization which in turn is better than progression.

RESULTS

Of 2006 individuals developing CRI, 21% subsequently improved eGFR, 67% stabilized and 12% progressed. Individuals remaining on tenofovir (TDF) or atazanavir boosted with ritonavir (ATV/r) 24 months post-CRI had worse eGFR outcomes compared with those unexposed [TDF: 0.47 (0.35-0.63) and ATV/r: 0.63 (0.48-0.82)]. Individuals off TDF for 12-24 months [0.75 (0.50-1.13)] or off ATV/r for more than 12 months [1.17 (0.87-1.57)] had similar eGFR outcomes as those unexposed to these antiretrovirals. Older age, hypertension, later date of CRI and diabetes were associated with worse eGFR outcomes.

CONCLUSION

Current TDF and ATV/r use after a diagnosis of CRI was associated with worse eGFR outcomes. In contrast, TDF and ATV/r discontinuation lead to similar longer term eGFR outcomes as in those unexposed, suggesting that these drug-associated eGFR declines may be halted or reversed after their cessation.

Absence of Decline of Kidney Function in Human Immunodeficiency Virus-Infected Patients Under Routine Clinical Management

BACKGROUND

Since the introduction of antiretroviral therapy (ART), human immunodeficiency virus (HIV)-infected patients have a drastically improved prognosis but at the same time they are also more affected by non-HIV related complications, such as chronic kidney disease. The objective of our study was to investigate the effect of proteinuria and tenofovir (TDF)-containing ART regimens on the temporal evolution of estimated glomerular filtration rate (eGFR).

METHODS

Between April 2008 and October 2012, we enrolled 395 patients with a complete renal evaluation among patients from the ANRS C03 Aquitaine cohort, a prospective hospital-based cohort of HIV-1-infected patients under routine clinical management in southwestern France. eGFR was estimated at each patient follow-up visit. A linear mixed model was used to analyze eGFR dynamics, accounting for change in TDF by modeling eGFR trajectory according to treatment periods.

RESULTS

At inclusion, 56.7% of patients were treated with TDF-containing ART regimens; prevalence of glomerular and tubular proteinuria was 7.9 and 10.8% respectively. A 1-year increase of cumulative exposure to TDF was significantly associated with a mean eGFR decrease of 1.27 mL/min/1.73 m2 (95% CI [-2.14 to -0.41]). Only a urine protein to creatinine ratio >100 mg/mmol and/or a urine albumin to creatinine ratio >70 mg/mmol were associated with eGFR trajectory (mean slope 6.18 mL/min/1.73 m2 per year; 95% CI [2.71 to 9.65]), whereas TDF use was not associated with such eGFR temporal evolution.

CONCLUSION

Decline in kidney function is limited under routine clinical management with monitoring of renal function and interventions including decision to continue or discontinue TDF.

Does first-line antiretroviral regimen impact risk for chronic kidney disease whatever the risk group?

OBJECTIVES

We used the D:A:D risk score for chronic kidney disease (CKD) for patients starting antiretroviral therapy (ART) in the recent years, and investigated whether specific regimens enhanced the risk of CKD in the different risk groups.

DESIGN

Retrospective analysis of a prospectively collected cohort of French HIV-infected patients.

METHODS

Patients who started their first ART after January the 1st, 2004 with a baseline estimated glomerular filtration rate (eGFR) greater than 60 ml/min per 1.73 m were analyzed. CKD was defined by confirmed eGFR less than 60 ml/min per 1.73 m. Incidence of CKD was estimated by Kaplan-Meier method, and Poisson regression models were used to quantify the relationship between CKD, exposure to the initial ART regimens and the D:A:D score.

RESULTS

We included 6301 patients representing 21 936 person-years of follow-up (PYFU), median eGFR at baseline was 101 ml/min per 1.73 m (inter-quartile range 86; 118) and CKD incidence 9.6/1000 PYFU. Five years probabilities of CKD were 0.65, 4.6 and 15.9% in the low, medium and high-risk groups, respectively. In patients treated with a boosted protease inhibitor, incidences rates were 7.1/1000 and 9.0/1000 PYFU in the absence or presence of tenofovir, respectively, and markedly increased with increasing risk score. In the low-risk group the treatment choice had no impact on CKD incidence.

CONCLUSION

When choosing the ideal first antiretroviral regimen for one given patient, clinicians should rely on the D:A:D score and avoid some drugs in high-risk patients, whereas in low-risk patients classic regimens may be safely prescribed, with an economic benefit due to soon available generic formulations.

Tenofovir exposure alters associations of serum bicarbonate with chronic kidney disease risk in HIV-infected veterans

OBJECTIVE

Among HIV-infected persons, tenofovir disoproxil fumarate (TDF) use is associated with higher risk of developing chronic kidney disease (CKD). Because lower serum bicarbonate concentrations may precede CKD onset, this study investigated the associations between TDF use and bicarbonate concentrations, and between bicarbonate with CKD risk among TDF users and nonusers.

METHODS

Retrospective cohort study of 16,070 HIV-infected US veterans who initiated antiretroviral therapy between 1997-2011. The association between TDF use with longitudinal bicarbonate concentrations and associations between bicarbonate with incident CKD stratified by TDF use (never, initial, and later user) were evaluated.

RESULTS

Compared with TDF users, never users had faster declines in bicarbonate concentrations: change in bicarbonate -0.11 mmol/l per year (95% confidence interval -0.16, -0.05), compared with -0.04 mmol/l per year (-0.06, 0.05) in initial users and -0.02 mmol/l per year (-0.05, 0.01) in later users. Low baseline bicarbonate (<22 mmol/l) was significantly associated with CKD risk among TDF never users (1.80; 1.21, 2.68), but not among TDF users (0.98; 0.69, 1.38). Similarly, declining bicarbonate concentrations were associated with higher CKD risk among never users (hazard ratio 1.67 per mmol/l; 1.34, 2.08), but not among TDF users (1.09; 0.98, 1.22). Interactions were highly significant for both analyses (P value = 0.001).

CONCLUSION

Despite associations with nephrotoxicity, TDF use was associated with higher serum bicarbonate concentrations longitudinally. Additionally, TDF use obscured the strong associations of bicarbonate with CKD risk in HIV-infected persons. Therefore, the role of bicarbonate concentrations as a tool to monitor kidney health in HIV-infected persons may be limited in the setting of TDF use.

Racial Disparities in Creatinine-based Kidney Function Estimates Among HIV-infected Adults

OBJECTIVE

The aim of our study was to investigate whether current eGFR equations in clinical use might systematically over-estimate the kidney function, and thus misclassify CKD status, of Black Americans with HIV. Specifically, we evaluated the impact of removing the race coefficient from the MDRD and CKD-EPI equations on comparisons between Black and White HIV-infected veterans related to: 1) the prevalence of reduced eGFR; 2) the distribution of eGFR values; and 3) the relationship between eGFR and all-cause mortality.

DESIGN

Retrospective cohort study.

SETTING

The Department of Veterans Affairs (VA) HIV Clinical Case Registry (CCR), which actively monitors all HIV-infected persons receiving care in the VA nationally.

PATIENT/PARTICIPANTS

21,905 treatment-naïve HIV-infected veterans.

MAIN OUTCOME MEASURES

Estimated glomerular filtration rate (eGFR) using the abbreviated Modification of Diet in Renal Disease (MDRD) formula with and without (MDRD-RCR) the race coefficient and all-cause mortality.

RESULTS

Persons with eGFR <45 mL/min/1.73m(2) had a higher risk of death compared with those with eGFR >80 mL/min/1.73m(2) among both Blacks (HR=2.8, 95%CI: 2.4-3.3) and Whites (HR=1.9, 95%CI: 1.4-2.6), but the association appeared to be stronger in Blacks (P=.038, test for interaction). Blacks with eGFR 45-60 mL/min/1.73m(2) also had a higher risk of death (HR=1.7, 95%CI: 1.4-2.1) but Whites did not (HR=.86, 95%CI: .67-1.10; test for interaction: P<.0001). Racial differences were substantially attenuated when eGFR was re-calculated without the race coefficient.

CONCLUSIONS

Our findings suggest that clinicians may want to consider estimating glomerular filtration rate without the race coefficient in Blacks with HIV.

Nephrotoxicity during tenofovir treatment: a three-year follow-up study in a Brazilian reference clinic

In this study, 275 patients in use of tenofovir were retrospectively followed-up for three years to evaluate risk factors involved in impaired renal function. Analysis of variance (ANOVA) and Tukey's test were used to verify any differences in creatinine levels and estimated clearance at 0, 6, 12, 24 and 36 months, adjusting for the co-variables sex, skin color, age >50 years, arterial hypertension, diabetes and the use of the ritonavir-boosted protease inhibitors (PI/r) lopinavir/r or atazanavir/r. The software package STATISTICA 10(®) was used for statistical analysis. The patients' mean age was 43.2±10.7 years. Systemic arterial hypertension (SAH) and diabetes were found in 20.4% and 8.7% of the patients, respectively. Overall, 96.7% were on tenofovir associated with lamivudine (TDF+3TC), 39.3% on lopinavir/r, 29.8% on efavirenz, and 17.6% on atazanavir/r. There was a statistically significant difference in estimated creatinine clearance at 24 months, when the co-variables male (F=3.95; p=0.048), SAH (F=6.964; p=0.009), and age over 50 years (F=45.81; p<0.001) were taken into consideration. Analysis of the co-variable use of atazanavir/r showed a tendency toward an increased risk over time (F=2.437; p=0.063); however, no significant time interaction was seen. At 36-month, a statistically significant difference was found for age over 50 years, (F=32.02; p<0.05) and there was a significant time-by-sex interaction (F=3.117; p=0.0149). TDF was discontinued in 12 patients, one because of a femoral neck fracture (0.7%) and 11 due to nephrotoxicity (4%). Of these latter cases, 9/11 patients were also using protease inhibitors. These data strongly alert that tenofovir use should be individualized with careful attention to renal function especially in male patients, over 50 years, with SAH, and probably those on ATV/r.

Epidemiology, clinical characteristics, and management of chronic kidney disease in human immunodeficiency virus-infected patients

Antiretroviral therapy has markedly reduced acquired immune deficiency syndrome-related deaths and opportunistic infectious diseases. This has resulted in prolonged survival of individuals infected with the human immunodeficiency virus (HIV). However, this improvement in survival has been accompanied by an increase in the incidence of chronic kidney disease (CKD) and end-stage renal disease. CKD is now epidemic among HIV-infected populations in both Western and Eastern countries. Risk factors associated with CKD in HIV-infected populations include aging, hypertension, diabetes mellitus, co-infection with hepatitis C virus, a low CD4 cell count, and a high HIV viral load. Clinical experience has shown that HIV-infected individuals often have one or more concurrent risk factors for CKD. The cumulative effect of multiple risk factors on the development of CKD should be noted in this population. Glomerular disease directly related to HIV infection, so-called HIV-associated nephropathy, remains an important cause of CKD among a limited HIV population of African descent, but is less likely to be common among other urban HIV populations. The impact of exposure to nephrotoxic antiretroviral agents on the development of kidney disease is both an old and a new concern. In particular, the association of tenofovir with kidney tubular injury has been an area of great interest. The findings regarding tenofovir's adverse effect on long-term kidney function vary among studies. The early identification and treatment of CKD is recommended for reducing the burden of patients requiring dialysis in HIV-infected populations. Periodic monitoring of urinary concentrations of albumin, protein, and tubular injury markers such as low-molecular-weight proteins may be useful for the early diagnosis of patients at risk for incident CKD. This review focuses on recent epidemiology, clinical characteristics, and management of CKD in a contemporary HIV-infected population.

Development and validation of a risk score for chronic kidney disease in HIV infection using prospective cohort data from the D:A:D study

BACKGROUND

Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice.

METHODS AND FINDINGS

A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with ≥3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR ≤ 60 ml/min/1.73 m2. Poisson regression was used to develop a risk score, externally validated on two independent cohorts. In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1:393 chance of developing CKD in the next 5 y in the low risk group (risk score < 0, 33 events), rising to 1:47 and 1:6 in the medium (risk score 0-4, 103 events) and high risk groups (risk score ≥ 5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1,702 (95% CI 1,166-3,367); NNTH was 202 (95% CI 159-278) and 21 (95% CI 19-23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506-1462), 88 (95% CI 69-121), and 9 (95% CI 8-10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor. The Royal Free Hospital Clinic Cohort included 2,548 individuals, of whom 94 individuals developed CKD (3.7%) during 18,376 PYFU (median follow-up 7.4 y, range 0.3-12.7 y). Of 2,013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8,452 PYFU (median follow-up 4.1 y, range 0.6-8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria.

CONCLUSIONS

Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.