HIV and the kidney: a spotlight on racial disparities

COHORT PROFILE: The Complications of Long-Term Antiretroviral Therapy study in Uganda (CoLTART), a prospective clinical cohort

BACKGROUND

Antiretroviral therapy (ART) improves the survival and quality of life of HIV-positive individuals, but the effects of long-term ART use do eventually manifest. The Complications of Long-Term Antiretroviral Therapy cohort study in Uganda (CoLTART) was established to investigate the metabolic and renal complications of long-term ART use among Ugandan adults. We describe the CoLTART study set-up, aims, objectives, study methods, and also report some preliminary cross-sectional study enrolment metabolic and renal complications data analysis results.

METHODS

HIV-positive ART naïve and experienced adults (18 years and above) in Uganda were enrolled. Data on demographic, dietary, medical, social economic and behaviour was obtained; and biophysical measurements and a clinical examination were undertaken. We measured: fasting glucose and lipid profiles, renal and liver function tests, full blood counts, immunology, virology and HIV drug resistance testing. Plasma samples were stored for future studies.

RESULTS

Between July 2013 and October 2014, we enrolled 1095 individuals, of whom 964 (88.0%) were ART experienced (6 months or more), with a median of 9.4 years (IQR 7.0-9.9) on ART. Overall, 968 (88.4%) were aged 35 years and above, 711 (64.9%) were females, 608 (59.6%) were or had ever been on a Tenofovir ART regimen and 236 (23.1%) on a Protease Inhibitor (PI) regimen. There were no differences in renal dysfunction between patients on Tenofovir and Non-Tenofovir containing ART regimens. Patients on PI regimens had higher total cholesterol, lower high density lipoprotein, higher low density lipoprotein, higher triglycerides, and a high atherogenic index for plasma than the non-PI regimen, p = 0.001 or < 0.001. Patients on Non-PI regimens had higher mean diastolic hypertension than patients on PI regimens, p < 0.001.

CONCLUSIONS

Our finding of no differences in renal dysfunction between patients on Tenofovir and those on Non-Tenofovir containing ART regimens means that Tenofovir based first line ART can safely be initiated even in settings without routine renal function monitoring. However, integration of cardiovascular risk assessment, preventive and curative measures against cardiovascular disease are required. The CoLTART cohort is a good platform to investigate the complications of long-term ART use in Uganda.

Glomerular dysfunction and associated risk factors over 4-5 years following antiretroviral therapy initiation in Africa

BACKGROUND

The aim of this study was to investigate long-term renal function in HIV-infected adults initiating antiretroviral therapy (ART) with a CD4(+) T-cell count < 200 cells/mm³ in Africa.

METHODS

This was an observational analysis within the DART trial randomizing 3,316 adults to routine laboratory and clinical monitoring (LCM) or clinically driven monitoring (CDM). Serum creatinine was measured pre-ART (all ≤ 360 μmol/l), at weeks 4 and 12, then every 12 weeks for 4-5 years; estimated glomerular filtration rate (eGFR) was determined using the Cockcroft-Gault formula. We analysed eGFR changes, and cumulative incidences of eGFR< 30 ml/min/1.73 m² and chronic kidney disease (CKD; <60 ml/min/1.73 m² or 25% decrease if <60 ml/min/1.73 m² pre-ART; confirmed >3 months).

RESULTS

At ART initiation, median CD4(+) T-cell count was 86 cells/mm³; 1,492 (45%) participants had mild (60-< 90 ml/min/1.73 m²), 237 (7%) moderate (30-<60 ml/min/1.73 m² and 7 (0.2%) severe (15-<30 ml/min/1.73 m²) decreases in eGFR. First-line ART was zidovudine/lamivudine plus tenofovir (74%), abacavir (9%) or nevirapine (17%). By 4 years, cumulative incidence of eGFR<30 ml/min/1.73 m² was 2.8% (n=90) and CKD was 5.0% (n=162). Adjusted eGFR increases to 4 years were 1, 9 and 6 ml/min/1.73 m² with tenofovir, abacavir and nevirapine, respectively (P<0.001), and 4 and 2 ml/min/1.73 m² for LCM and CDM, respectively (P=0.005; 2 and 3 ml/min/1.73 m² to 5 years; P=0.81).

CONCLUSIONS

On all regimens and monitoring strategies, severe eGFR impairment was infrequent; differences in eGFR changes were small, suggesting that first-line ART, including tenofovir, can be given safely without routine renal function monitoring.

Prevalence of chronic kidney disease among people living with HIV/AIDS in Burundi: a cross-sectional study

BACKGROUND

Since little is known about chronic kidney disease (CKD) among people living with HIV/AIDS (PLWHA) in Sub-Saharan Africa, the prevalence and nature of CKD were assessed in Burundi through a multicenter cross-sectional study.

METHODS

Patients underwent assessments at baseline and 3 months later. Glomerular Filtration Rate (GFR) was estimated using abbreviated 4-variable Modification of Diet in Renal Diseases (MDRD) and Cockroft-Gault estimation methods. Patients were classified at month 3 into various CKD stages using the National Kidney Foundation (NKF) definition, which combines GFR and urinary abnormalities. Risk factors for presence of proteinuria (PRO) and aseptic leukocyturia (LEU) were further analyzed using multiple logistic regression.

RESULTS

Median age of the patients in the study (N = 300) was 40 years, 70.3% were female and 71.7% were on highly active antiretroviral therapy. Using the MDRD method, CKD prevalence in patients was 45.7%, 30.2% of whom being classified as stage 1 according to the NKF classification, 13.5% as stage 2 and 2% as stage 3. No patient was classified as stage 4 or 5. Among CKD patients with urinary abnormality, PRO accounted for 6.1% and LEU for 18.4%. Significant associations were found between LEU and non-steroidal anti-inflammatory drug (NSAID) use, previous history of tuberculosis, low body mass index and female gender and between PRO and high viral load.

CONCLUSION

Our study, using a very sensitive definition for CKD evaluation, suggests a potentially high prevalence of CKD among PLWHA in Burundi. Patients should be regularly monitored and preventative measures implemented, such as monitoring NSAID use and adjustment of drug dosages according to body weight. Urine dipsticks could be used as a screening tool to detect patients at risk of renal impairment.

Impact of comorbidities and drug therapy on development of renal impairment in a predominantly African American and Hispanic HIV clinic population

Purpose

Renal impairment in human immunodeficiency virus (HIV)-infected patients could potentially be caused by many factors. HIV-related renal impairment risks have been little studied in African Americans and Hispanics. We investigated the impact of HIV itself, highly active antiretroviral therapy (HAART), comorbidities, and non-HIV-related drug treatment on glomerular filtration rate in a predominantly African American/Hispanic HIV-infected population who had received HAART for at least one year. This study was a retrospective electronic medical record database evaluation of renal impairment risks in a largely African American/Hispanic HIV population obtaining medical care at an HIV clinic in Dallas, Texas.

Methods

Proportional hazards models were used to investigate an association between an estimated glomerular filtration rate decrease >25% from baseline (ie, renal impairment) and demographics, antiretroviral/nonantiretroviral medications, comorbidities (hypertension, diabetes mellitus, hepatitis C virus [HCV] infection, hepatitis B virus [HBV] infection), CD4+ counts, viral load, and duration patients were monitored at the clinic (time on study).

Results

In total, 323 patients were evaluated: 82% males; 61% African American/12% Hispanic/19% Caucasian; mean age 37.9 years (standard deviation [SD] 8.5); 6% HBV-positive; 34% HCV-positive; 29% hypertensive; 3% diabetic; 52% tenofovir-treated; mean weight 75.4 kg (SD, 15.4); mean estimated glomerular filtration 114.5 mL/min/1.73 m² (SD, 36.7) using the Modification of Diet in Renal Disease (MDRD) calculation method; mean creatinine clearance (from which estimated glomerular filtration was extrapolated) by the Cockcroft-Gault calculation method 120.6 mL/min/1.73 m² (SD, 41.2); mean time on study 2.7 years (SD, 1.0 year). An estimated glomerular filtration rate decrease of >25% from baseline was significantly associated with time on study (P = 0.0017; hazards ratio [HR] = 0.999) and hypertension (HR = 1.706; P = 0.0158) by the MDRD method, and with age (HR = 1.039; P = 0.0077), weight (HR = 0.987; P = 0.0023), and time on study (HR = 0.999; P = 0.0043) by extrapolation of Cockcroft-Gault creatinine clearance calculation. No specific HAART agent was associated with significant renal impairment risk by the definition used in this study.

Conclusion

This retrospective database study showed time on study, hypertension, weight, and age to be the only significant predictors of an estimated glomerular filtration rate decrease >25% from baseline.