Risk factors associated with albuminuria in Rwanda: results from a STEPS survey

BACKGROUND

Non-communicable diseases (NCDs) are a growing burden which affects every part of the world, including developing countries. Chronic kidney disease (CKD) has varied etiology which can result from or complicate other NCDs such as diabetes and cardiovascular diseases. The growing prevalence of NCDs coupled with the increasing age in most developing countries, has seen a marked increase of CKD in these settings. CKD has been described as "the most neglected NCD" and greatly affects the quality of life of patients. It also places a huge economic burden on societies. However, few epidemiological data exist, particularly in sub-Saharan Africa. Assessment of the prevalence of albuminuria as a marker of kidney damage and CKD progression and its main risk factors was thus needed in Rwanda.

METHODS

This study analyzed data collected during the first STEPwise approach to NCD risk factor Surveillance (STEPS) survey in Rwanda, conducted from 2012 to 2013, to assess the prevalence of albuminuria. A multistage cluster sampling allowed to select a representative sample of the general population. Furthermore, descriptive, as well as univariable analyses and multiple logistic regression were performed to respond to the research question.

RESULTS

This survey brought a representative sample of 6,998 participants, among which 4,384 (62.65%) were female. Median age was 33 years (interquartile range, IQR 26-44), and over three quarters (78.45%) lived in rural areas. The albuminuria prevalence was 105.9 per 1,000 population. Overall, semi-urban and urban residency were associated with lower odds of CKD (odds ratio, OR 0.36, CI 0.23-0.56, p<0.001 and OR 0.34, CI 0.23-0.50, p<0.001, respectively) than rural status. Being married or living with a partner had higher odds (OR 1.44 (CI 1.03-2.02, p=0.031) and OR 1.62 (CI 1.06-2.48, p=0.026), respectively) of CKD than being single. Odds of positive albuminuria were also greater among participants living with human immunodeficiency virus (HIV) (OR 1.64, CI 1.09- 2.47, p=0.018). Gender, age group, smoking status and vegetable consumption, body mass index (BMI) and hypertension were not associated with albuminuria.

CONCLUSION

The albuminuria prevalence was estimated at 105.9 per 1,000 in Rwanda. Rural residence, partnered status and HIV positivity were identified as main risk factors for albuminuria. Increased early screening of albuminuria to prevent CKD among high-risk groups, especially HIV patients, is therefore recommended.

Safety of Tenofovir Alafenamide in People With HIV Who Experienced Proximal Renal Tubulopathy on Tenofovir Disoproxil Fumarate

BACKGROUND

Proximal renal tubulopathy (PRT) is an infrequent complication of tenofovir disoproxil fumarate (TDF). It remains to be established whether tenofovir alafenamide (TAF) can be safely administered to individuals who experienced PRT on TDF.

METHODS

Individuals with a history of TDF-associated PRT and current estimated glomerular filtration rate (eGFR) over 30 mL/min/1.73 m2 initiated TAF and were followed for 96 weeks. The primary outcome of interest was recurrent PRT. Secondary outcomes were changes in kidney biomarkers, bone biomarkers, and bone mineral density (BMD). Data were analyzed using multilevel mixed-effects linear regression models. The trial was registered under EudraCT 2016-003345-29.

RESULTS

All 31 participants [median age 55 (inter-quartile range 51, 60) years, 97% men, 87% White ethnicity] remained on TAF at week 96, and none developed glycosuria or recurrent PRT. Participants experienced small declines in eGFR-creatinine [-1.9 (95% confidence interval: -3.5 to -0.3) mL/min/1.73 m2/yr; P = 0.024], but not in eGFR-cystatin C [-0.9 (-2.1 to 0.4) mL/min/1.73 m2/yr; P = 0.16]. Ten (32%) and 5 (16%) participants experienced rapid (>5 mL/min/1.73 m2/yr) decline in eGFR-creatinine and eGFR-cystatin C. No significant change in other kidney biomarkers, bone turnover, or BMD was observed (P > 0.2).

CONCLUSIONS

In individuals with a history of PRT on TDF, 96 weeks of TAF was not associated with recurrent PRT or adverse effects on renal tubular function, bone turnover, or BMD. These data suggest that TAF is a treatment option for this vulnerable population.

Renal Function Impairment and Associated Factors Among Adult HIV-Positive Patients Attending Antiretroviral Therapy Clinic in Mettu Karl Referral Hospital: Cross-Sectional Study

BACKGROUND

Human immunodeficiency virus (HIV) affects every organ system in the body through impairment or by rendering the patient vulnerable to opportunistic infections. The kidney is the vital organ in the excretion of waste products and toxins (urea, creatinine and uric acid), and regulation of extracellular fluid volume, serum osmolality and electrolyte concentrations. The risk of kidney disease is greater in HIV-infected individuals than in the general population. This study aimed to assess the magnitude of renal function impairment and its associated factors among adult HIV-positive patients attending an ART clinic in Mettu Karl Referral Hospital, Mettu town, south-west Ethiopia.

METHODS

The institution-based, cross-sectional quantitative study was conducted from March 8 to May 30, 2020. A total of 352 clients participated and a systematic sampling technique was used to allocate study participants. Data were entered into Epi data and exported to SPSS version 22 for analysis. Bivariate analysis was conducted to identify candidate variables for multivariate analysis at P <0.25. Multivariable logistic regression analysis was conducted to determine the predictors of renal function impairment with ART. P value < 0.05 was considered to indicate statistical significance.

RESULTS

A total of 352 HIV-infected patients participated in this study with a response rate of 98.1%. Out of 352 HIV patients on ART, 73 (20.7%) were found to have renal function impairment. Cigarette smoking [AOR = 9.60, 95% CI: 4.73-19.48], diabetes mellitus [AOR = 6.16, 95% CI: 2.79-13.59], hypertension [AOR = 4.71, 95% CI: 1.98-11.17] and low CD4 count [AOR = 6.47, 95% CI: 3.31-12.64] were found to be independent predictors of renal function impairment among adult HIV positive patients.

CONCLUSION

The prevalence of renal function impairment among HIV patients on ART is high. Hypertension, diabetes, cigarette smoking and low CD4 count were associated factors of renal function impairment. HIV patients on ART should be regularly screened for early diagnosis and management of renal function impairment.

Serum electrolytes and renal alterations in HIV-seropositive Mexican subjects

To examine potential risk factors associated with biochemical alterations in renal function in a population diagnosed with HIV/AIDS undergoing antiretroviral treatment.This is an observational, transversal, and relational design study that included 179 HIV-seropositive subjects. Glucose serum, cholesterol, triglycerides, total proteins, albumin, creatine, urea, blood urea nitrogen (BUN), and electrolytes levels were determined for each individual. Renal function was evaluated through the glomerular filtration rate (GFR), using the CKD-EPI equation. Chronic kidney disease (CKD) was defined as estimated glomerular filtration rate  < 60 mL/min/1.73 m2. Univariate model significant variables, with a 95% confidence interval (CI), were included in a multivariate logistic regression analysis.CKD prevalence in patients was 7.3%, with comorbidities of 7.8% for type 2 diabetes mellitus, 7.3% for arterial hypertension, and 35.2% for dyslipidemia. Additionally, both hypernatremia and hypophosphatemia were detected in 57% (n = 102) of the patients. Multivariate logistic regression suggested that CD4+ T cell count < 200 (P = .02; OR 0.2; CI 95% 0.08-0.8) was associated to hyponatremia; similarly, detectable viral load was associated to hypokalemia (P = .02; OR 5.1; CI 95% 1.2-21.3), hypocalcemia (P = .01; OR 4.1; CI 95% 1.3-12.3), and hypermagnesemia (OR 3.9; CI 95% 1.1-13.6). Patient age was associated to both hypophosphatemia (P = .01; OR 2.4; CI 95% 1.1-5.0) and hypermagnesemia (P = .01; OR 2.8; IC 95% 1.1-7.0), and high creatinine levels were associated to nucleoside reverse transcriptase inhibitor treatment (P = .001; OR 42.5; CI 95% 2.2-806.9). Lastly, high BUN levels were associated to age (P = .03; OR 3.8; CI 95% 1.0-14.4), while GFR 60 to 89 mL/min/1.73 m2 was associated to dyslipidemia (P = .02; OR 2.2; CI 95% 1.1-4.5).CD4+ T cell and viral load were the main factors associated with renal biochemical alterations.

Bone loss in hepatitis B virus-infected patients can be associated with greater osteoclastic activity independently of the retroviral use

Nucleoside/nucleotide analogs such as tenofovir, have been used as long-term therapy for the treatment of hepatitis B and side effects such as the reduction in bone mineral density have been associated with their use. To determine the relationships between bone, hormonal, biochemical, and mineral parameters in patients with hepatitis B treated with nucleoside/nucleotide antiviral. A cross-sectional study was conducted with 81 adult patients with chronic hepatitis B infection. Dual-energy X-ray absorptiometry (DXA) was performed to assess bone mineral density. Biochemical analyses were performed for osteocalcin, deoxypyridinoline, parathyroid hormone, vitamin D, IGF-1, TSH, testosterone, estradiol, FSH, transaminases, urea, creatinine, calcium, serum and urinary phosphorus, magnesium, and FGF-23, body composition was performed by DXA. Participants, both gender, were divided according to the use of antiretrovirals: Group1: 27 inactive virus carriers without medication; Group2: 27 patients using tenofovir; and Group3: 27 patients using lamivudine or entecavir. DXA readings diagnosed osteopenia in the lumbar spine for 7.4% of individuals in Group1, 15% in Group2, and 3.7% in Group3. For all groups, we observed normal values in bone formation markers, osteocalcin levels as well as parathyroid hormone, insulin growth factor 1, and FGF-23. In all groups, we found increased levels of urinary deoxypyridinoline, a bone resorption marker. Increased levels in the bone resorption markers indicated a high resorptive activity of bone tissue. These data suggested high resorption activity of bone tissue in hepatitis B virus-infected patients independent of the use of antiretrovirals.

Chronic Kidney Disease and Associated Factors Among HIV Infected Patients Taking Tenofovir Disoproxil Fumarate Based Regimen in Ethiopia: A Hospital-Based Cross-Sectional Study

Background

Life expectancy of HIV patients has increased by the extensive use of antiretroviral therapies (ART), but ART predisposes patients to chronic non-communicable diseases including chronic kidney disease (CKD). Tenofovir disoproxil fumarate is one of the commonly used drugs in ART and is found to have more risk for developing CKD. In the study areas, there was no previous study addressing the prevalence of CKD, so the purpose of this study was to pinpoint the prevalence of CKD, and its associated factors.

Methods

A hospital-based cross-sectional study was employed at Tikur Anbessa Specialized Hospital (TASH) and Zewuditu Memorial Hospital (ZMH) from April 1 to June 30, 2019. The study participants were proportionally allocated to each hospital and a total of 243 eligible participants were selected conveniently from the two hospitals in the study period. Structured questionnaire and checklist were used to collect socio-demographic and clinical data of the participants. Blood samples (3–5 ml) were used to determine serum creatinine using calibrated fully automated Mind ray BS-200E, and glomerular filtration rate (GFR) was estimated using a chronic kidney disease epidemiology equation. Multivariate logistic regression was employed to identify factors associated with CKD, and a P-value of less than 0.05 was considered significant.

Results

In the present study, the prevalence of CKD (GFR <60 ml/min/1.73 m²) was 4.53% (95% CI = 2.3–8%). GFR was classified into stages, stage 5 (GFR <15), stage 4 (15–29.9), stage 3 (30–59.9), stage 2 (60–89.9), and stage 1 (≥90) were 0%, 0.4%, 4.1%, 38.3%, and 57.2%, respectively. In the multivariate logistic regression, age greater than 50 years old, and having cancer were significantly associated with CKD (AOR: 0.22, 95% CI = 0.05–0.88, P = 0.033, and AOR: 18.20, 95% CI = 122–271.77, P = 0.035, respectively).

Conclusion

Chronic kidney disease in HIV-infected patients receiving a TDF-based regimen requires attention. Age >50 years old, and having cancer as comorbidity were significantly associated with chronic kidney disease. Patients should be regularly monitored for early diagnosis and management of chronic kidney disease in a TDF-based regimen.

Bone mineral density, kidney function, weight gain and insulin resistance in women who switch from TDF/FTC/NNRTI to ABC/3TC/DTG

OBJECTIVES

Tenofovir disoproxil fumarate (TDF) is associated with reduced bone mineral density (BMD). We evaluated changes in BMD in women who switched from TDF, emtricitabine and a nonnucleoside reverse transcriptase inhibitor (TDF/FTC/NNRTI) to abacavir, lamivudine and dolutegravir (ABC/3TC/DTG).

METHODS

We conducted a randomized controlled trial in which women aged ≥40 years were randomized 1:2 to continue TDF/FTC/NNRTI or switch to ABC/3TC/DTG. The primary endpoint was change in total hip BMD measured by dual-energy X-ray absorptiometry at week 48. Secondary endpoints were changes in BMD of the lumbar spine and femoral neck and markers of bone turnover and kidney function up to week 48. We conducted exploratory analyses of weight gain, insulin resistance and metabolic syndrome. Primary and secondary endpoints were analysed by linear regression, with multiple imputation for missing time points.

RESULTS

In all, 91 women [mean age = 50.4 (standard deviation [SD] = 6.6) years, median CD4 cell count = 600 (interquartile range: 479-800) cells/µL] were randomized. Women who switched to ABC/3TC/DTG maintained viral suppression and experienced improvements in total hip BMD (mean adjusted difference = 1%, P = 0.027) and lumbar spine BMD (3%, P = 0.002), with no change in specific markers of bone turnover or renal tubular function. Although participants in the ABC/3TC/DTG arm gained more weight (1.8 kg, P = 0.046), the switch strategy was not associated with reduced insulin sensitivity or new-onset metabolic syndrome.

CONCLUSIONS

Switching from TDF/FTC/NNRTI to ABC/3TC/DTG resulted in improved BMD. Although weight gain was common in women who switched from TDF/FTC/NNRTI to ABC/3TC/DTG, we did not detect adverse effects on glucose homeostasis. Larger studies need to confirm these findings.

Estimated glomerular filtration rate slopes on tenofovir alafenamide

OBJECTIVES

The aim of the study was to analyse and compare estimated glomerular filtration rate (eGFR) slopes during exposure to tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF) in individuals who initiated TAF, regardless of prior regimen, before October 2016.

METHODS

An observational cohort study was conducted at 11 clinics in the UK and Ireland. Mixed effects models with random intercept and time terms fitted were used to generate and compare eGFR slopes while participants were exposed to TDF and TAF, with adjustment for age, eGFR at TDF/TAF initiation, gender, ethnicity, and time-updated CD4 cell count and HIV RNA measurements.

RESULTS

Data were available for 357 subjects (median age 50 years; 80% male; 82% white/other ethnicity; 51% men who have sex with men; median nadir CD4 count 216 cells/µL). The median duration of exposure to TAF was 2.0 (interquartile range 1.6, 2.3) years. At TAF initiation, the median CD4 count was 557 cells/µL, the median eGFR was 80 mL/min/1.73 m², and 86% had suppressed HIV infection. The mean adjusted eGFR slope during TDF and TAF exposure was -2.08 [95% confidence interval (CI) -2.24, -1.92] and 1.18 (95% CI 0.20, 1.52) mL/min/1.73 m²/year, respectively (P < 0.001). Individuals who experienced rapid eGFR decline (> 3 or 5 mL/min/1.73 m²/year) while receiving TDF experienced significant eGFR recovery while on TAF (P < 0.001).

CONCLUSIONS

Significant improvement in eGFR slope was observed in patients who switched from TDF- to TAF-containing antiretroviral regimens. These data provide further support for the renal safety of TAF, and for switching those who experience progressive worsening of renal function from TDF to TAF.

Early safety of tenofovir alafenamide in patients with a history of tubulopathy on tenofovir disoproxil fumarate: a randomized controlled clinical trial

OBJECTIVES

The aim of the study was to assess the effect of tenofovir alafenamide (TAF) on kidney and bone biomarkers in patients who developed proximal renal tubulopathy (PRT) while receiving tenofovir disoproxil fumarate (TDF).

METHODS

Individuals with a history of TDF-associated PRT and currently suppressed HIV infection on a tenofovir-sparing regimen were randomized 1:1 to continue current antiretroviral therapy or initiate emtricitabine (F)/TAF with discontinuation of nucleoside reverse transcriptase inhibitors (NRTIs) as appropriate. Renal and bone biomarkers were analysed at baseline, week 4 and week 12. The primary outcome was the mean difference between study arms in urine retinol-binding protein:creatinine ratio (RBPCR) change from baseline to week 12. Data were analysed using linear regression, with robust standard errors (primary outcome), and repeated measures mixed effects models (secondary outcomes). The trial was registered under European Union Drug Regulating Authorities Clinical Trials Database 2016-003345-29.

RESULTS

We randomized 31 individuals [mean age 52.4 (standard deviation 0.3) years; 97% male; 90% white); all completed the study. At 12 weeks, there was no difference in change in RBPCR (β 19.6; 95% confidence interval -35.3, 74.5; P = 0.47), and no difference in change in estimated glomerular filtration rate (eGFR) (based on creatinine or cystatin C), albuminuria, proteinuria, renal phosphate or urea handling, (fasting) urine osmolality, parathyroid hormone and bone turnover markers in the control versus the F/TAF exposed groups. No cases of PRT were observed.

CONCLUSIONS

In people with a history of proximal renal tubulopathy while on TDF, 12-week exposure to TAF did not adversely affect renal tubular function. These data support continued evaluation of the long-term safety of TAF in this group of patients.

Association of HIV Suppression With Kidney Disease Progression Among HIV-Positive African Americans With Biopsy-Proven Classic FSGS

BACKGROUND

In the era of combined antiretroviral therapy, classic focal segmental glomerulosclerosis (FSGS) is the most common histopathological finding in African American HIV-positive patients with kidney disease. We sought to determine whether HIV suppression is associated with lower risk of progression to end-stage renal disease (ESRD) among HIV-positive African Americans with biopsy-confirmed classic FSGS.

METHODS

HIV-positive African Americans who underwent kidney biopsies at a single tertiary hospital between January 1996 and June 2011 were confirmed as having classic FSGS by the presence of segmental glomerulosclerosis without features of HIV-associated nephropathy. Multivariable Cox proportional hazards models were used to examine the independent association of viral suppression (HIV-RNA < 400 copies per milliliter at biopsy) with time to progression to ESRD.

RESULTS

Of the 55 HIV-positive African Americans with classic FSGS, 26 had suppressed viral loads at the time of biopsy. Compared to viremic patients, those who were virally suppressed had a significantly higher mean CD4 cell count (452 vs. 260 cell/mm, respectively; P = 0.02) and median estimated glomerular filtration rate (53.5 vs 35.5 mL/min/1.73 m, respectively; P = 0.002). Adjusting for sex and baseline CD4 cell count, estimated glomerular filtration rate, and proteinuria, those with HIV-RNA levels <400 copies per milliliter at baseline had a 75% lower risk of progressing to ESRD (hazard ratio = 0.25; 95% CI: 0.07 to 0.88) during a median follow-up time of 2.70 years (interquartile range: 0.80-5.15 years).

CONCLUSIONS

HIV suppression is associated with significantly lower risk of progression to ESRD among HIV-infected African Americans with classic FSGS, supporting the potential role of combined antiretroviral therapy for this histopathology in addition to HIV-associated nephropathy among HIV-positive individuals.

Chronic Kidney Disease Risk in African and Caribbean Populations With HIV

We conducted an observational cohort study of end-stage kidney disease (ESKD) in >7000 African and Caribbean people with HIV in the UK. Using Poisson regression and East Africans as the reference group, the adjusted incidence rate ratio (95% confidence interval) of ESKD was 3.14 (1.26–7.84) in Southern Africans, 6.35 (2.53–15.96) in West Africans, and 5.26 (1.91–14.43) in Caribbeans. Higher CD4 cell count and suppressed HIV replication were associated with reduced risk of ESKD. The risk of ESKD varied among HIV-positive people of African heritage, with the highest rates observed in those of West African descent.

Kidney disease in Africans with HIV and tuberculosis

OBJECTIVE

To describe the spectrum of kidney disease in African patients with HIV and tuberculosis (TB).

METHODS

We used data from three cohorts: consecutive patients with HIV/TB in South London (UK, 2004-2016; n = 95), consecutive patients with HIV/TB who underwent kidney biopsy in Cape Town (South Africa, 2014-2017; n = 70), and consecutive patients found to have HIV/TB on autopsy in Abidjan (Cote d'Ivoire, 1991; n = 100). Acute kidney injury (AKI) was ascertained using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. In the Cape Town cohort, predictors of recovery of kidney function at 6 months were assessed using Cox regression.

RESULTS

In the London cohort, the incidence of moderate/severe AKI at 12 months was 15.1 (95% CI 8.6-26.5) per 100 person-years, and the prevalence of chronic and end-stage kidney disease (ESKD) 13.7 and 5.7%, respectively. HIV-associated nephropathy (HIVAN) was diagnosed in 6% of patients in London, and in 6% of autopsy cases in Abidjan. Evidence of renal TB was present in 60% of autopsies in Abidjan and 61% of kidney biopsies in Cape Town. HIVAN and acute tubular necrosis (ATN) were also common biopsy findings in Cape Town. In Cape Town, 40 patients were dialyzed, of whom 28 (70%) were able to successfully discontinue renal replacement therapy. Antiretroviral therapy status, CD4 cell count, estimated glomerular filtration rate (eGFR) at biopsy and renal histology, other than ATN, were not predictive of eGFR recovery.

CONCLUSION

Kidney disease was common in Africans with HIV/TB. Monitoring of kidney function, and provision of acute dialysis to those with severe kidney failure, is warranted.

Predictive factors of renal impairment in HIV-infected patients on antiretroviral therapy: Results from the VACH longitudinal cohort study

BACKGROUND

The use of combination antiretroviral therapy has led to dramatic improvements in the life expectancy of HIV-infected persons. As result, the HIV population is aging and increasingly facing illnesses typically seen in the elderly, such as chronic kidney disease (CKD).

METHODS

A retrospective longitudinal study was conducted using data from years 2010 and 2014 in all HIV-infected persons enrolled at the Spanish VACH cohort. We analyzed the prevalence and the predictive factors for developing CKD (estimated glomerular filtration rate, eGFR<60mL/min/1.73m²).

RESULTS

The CKD prevalence at baseline was 456/8968, 5.1% [4.6-5.6%]. Of 8512 HIV-positive individuals examined without CKD at baseline (73.7% male, median age 44 years-old), 2.15% developed CKD (eGFR<60mL/min/1.73m²). The odds ratios [95%CI] for the independent predictive factors identified were gender (male) 0.54 [0.39-0.75], age (per year) 1.08 [1.07-1.10], AIDS diagnosis 1.40 [1.03-1.91], protease inhibitor-based regimens 1.49 [1.10-2.02], hypertension 1.37 [0.94-1.99], diabetes 1.84 [1.33-2.55] and history of cardiovascular events 1.66 [0.96-2.86].

CONCLUSION

The prevalence and risk factors for CKD and its progression are high in the VACH cohort. Thus, preventive measures such as control of hypertension, diabetes and obesity, as well as efforts for avoiding exposure to nephrotoxic drugs, including some antiretrovirals, are warranted in this aging HIV population.

Prevalence of hypertension among patients aged 50 and older living with human immunodeficiency virus

BACKGROUND

Hypertension is one of the common medical conditions observed among patients aged 50 years and elder living with HIV (EPLWH) and to date no systematic review has estimated its global prevalence.

PURPOSE

To conduct a systematic review to estimate the global prevalence of hypertension among EPLWH.

DATA SOURCES

PubMed/MEDLINE, Embase, the Cochrane Library, and Global Health databases for relevant publications up till May 25, 2018.

STUDY SELECTION

Observational studies (cohort or cross-sectional studies) that estimated the prevalence of hypertension among EPLWH.

DATA EXTRACTION

Required data were extracted independently by three reviewers and the main outcome was hypertension prevalence among EPLWH.

DATA SYNTHESIS

The 24 (n = 29,987) eligible studies included were conducted in North America, Europe, Africa, and Asia. A low level bias threat to the estimated hypertension prevalence rates was observed. The global prevalence of hypertension among EPLWH was estimated at 42.0% (95% CI 29.6%-55.4%), I = 100%. The subgroup analysis showed that North America has the highest prevalence of hypertension 50.2% (95% CI 29.2% -71.2%) followed by Europe 37.8% (95% CI 30.7%-45.7%) sub-Saharan Africa 31.9% (95% CI 18.5% -49.2%) and Asia 31.0% (95% CI 26.1%-36.3%). We found the mean age of the participants explaining a considerable part of variation in hypertension prevalence.

CONCLUSION

This study demonstrated that two out of five EPLWH are hypertensive. North America appears to have the highest prevalence of hypertension followed by Europe, sub-Saharan Africa (SSA) and Asia respectively. Findings from this study can be utilized to integrate hypertension management to HIV management package. (Registration number: CRD42018103069).

Reduced Kidney Function in Tenofovir Disoproxil Fumarate Based Regimen and Associated Factors: A Hospital Based Prospective Observational Study in Ethiopian Patients

Purpose

Tenofovir disoproxil fumarate (TDF), a drug broadly used in combination antiretroviral therapy, is associated with renal dysfunction but the prevalence varied from country to country and it is not known in Ethiopia. The objectives of this study were to assess the prevalence of renal dysfunction and risk factors associated with it and the mean change in estimated glomerular filtration rate in human immunodeficiency virus infected patients receiving TDF based antiretroviral regimen at Tikur Anbessa Specialized Hospital.

Method

It was a hospital based prospective cohort study. The study participants were treatment naïve HIV infected patients initiating TDF containing combination antiretroviral therapy or switched to it because of adverse events. Multivariable logistic analysis was used to identify variables which have significant association.

Result

A total of 63 study participants were studied, 16 (25.4%) of whom had fall in eGFR greater than 25% relative to baseline. Only age greater than 50 years, baseline CD4 count less than 200 cells/mm³, and baseline proteinuria were significantly associated with renal dysfunction in multivariable logistic regression. There was -8.4 ml/min/1.73m² mean change in estimated glomerular filtration rate relative to baseline at six months of study.

Conclusion

The renal dysfunction (defined as decline in eGFR greater than 25%) was found in a quarter of the study population. The long term impact and the clinical implication of it are not clear. Future prospective study is required with large sample size and long duration to ascertain the prevalence of decline greater than 25% in estimated glomerular filtration rate and its progression to chronic kidney disease.

Rate of cardiovascular, renal and bone disease and their major risks factors in HIV-infected individuals on antiretroviral therapy in Spain

BACKGROUND

The life expectancy of HIV-infected individuals has dramatically improved with potent antiretroviral therapies. However, organ-specific toxicities of some antiretrovirals and persistent inflammation and immune activation due to residual virus replication account for a high burden of age-associated comorbidities in the HIV population.

METHODS

The prevalence of overt cardiovascular, renal and bone diseases as well as their major risk factors were cross-sectionally examined during the year 2014 in the VACH cohort, a large nationwide population of HIV-infected individuals in Spain.

RESULTS

A total of 10,897 HIV-infected patients were examined. Seventy-one point four percent were male and the mean age was 48 years. Mean time since HIV diagnosis was 15.8 years and mean time on antiretroviral therapy was 13.1 years. The proportion of patients with undetectable viral load was 87.1%, whereas 65.7% had CD4 counts>500 cells/mm³. Overall, cardiovascular, renal and bone disease were recorded in 4.7%, 5.9% and 2.8%, respectively. The prevalence of major risk factors was as follows: smoking 51.3%, alcohol abuse 7.8%, overweight/obesity 42.2%, diabetes 19.9%, dyslipidaemia 72.6%, hypertension 25.6%, and osteoporosis 11.1%. In the subset of patients older than 55 years-old (18%), all figures for overt disease and their major risk factors were significantly greater.

CONCLUSION

Major age-related medical conditions and most of their risk factors are highly prevalent in HIV-infected individuals on long-term antiretroviral therapy in Spain. Preventive actions, including careful selection of antiretroviral agents, should be prioritized in the ageing HIV population.

Lipodystrophy Increases the Risk of CKD Development in HIV-Positive Patients in Switzerland: The LIPOKID Study

Introduction

Antiretroviral therapy has improved the life expectancy of patients living with HIV. However, lipodystrophy syndrome (LD) remains prevalent, affecting mostly patients treated with first-generation antiretroviral drugs. This syndrome is characterized by changes in body fat distribution with or without associated metabolic changes. Here, we studied whether clinically evaluated LD is independently associated with chronic kidney disease (CKD) development (sustained estimated glomerular filtration rate [eGFR] < 60 ml/min per 1.73 m²) in HIV-positive patients.

Methods

We conducted a prospective cohort study (the LIPOKID Study) among all the patients from the Swiss HIV Cohort Study (SHCS) with an eGFR >60 ml/min per 1.73 m² upon their entry into the cohort with more than 3 months of follow-up from January 2002 to August 2016. Cox regression models were used to estimate the association between LD and CKD development.

Results

Among the 5384 patients included, 1341 (24.9%) developed LD during the follow-up. The mean follow-up time was 72.3 months (SD ±48.4). In total, 252 patients (4.7%) reached the primary endpoint after a median time of 51.3 months (±SD 39.9 months) from inclusion. A diagnosis of LD significantly increased the risk of an eGFR on univariate analysis (hazard ratio [HR] = 2.72; 95% confidence interval [95% CI] = 2.07−3.58; P < 0.001) and remained significantly higher after adjustment for known HIV and non-HIV risk factors for CKD (HR = 2.37; 95% CI = 1.67−3.36; P < 0.001). The effect of LD on CKD was not mediated through the use of nephrotoxic antiretroviral drugs.

Conclusion

Lipodystrophy syndrome is independently associated with CKD after adjustment for previously reported risk factors.

Chronic kidney disease in the global adult HIV-infected population: A systematic review and meta-analysis

INTRODUCTION

The widespread use of antiretroviral therapies (ART) has increased life expectancy in HIV patients, predisposing them to chronic non-communicable diseases including Chronic Kidney Disease (CKD). We performed a systematic review and meta-analysis (PROSPERO registration number CRD42016036246) to determine the global and regional prevalence of CKD in HIV patients.

METHODS

We searched PubMed, Web of Science, EBSCO and AJOL for articles published between January 1982 and May 2016. CKD was defined as estimated glomerular filtration rate (eGFR) <60ml/min using the MDRD, Cockcroft-Gault or CKD-EPI equations. Random effects model was used to combine prevalence estimates from across studies after variance stabilization via Freeman-Tukey transformation.

RESULT

Sixty-one eligible articles (n = 209,078 HIV patients) in 60 countries were selected. The overall CKD prevalence was 6.4% (95%CI 5.2-7.7%) with MDRD, 4.8% (95%CI 2.9-7.1%) with CKD-EPI and 12.3% (95%CI 8.4-16.7%) with Cockcroft-Gault; p = 0.003 for difference across estimators. Sub-group analysis identified differences in prevalence by WHO region with Africa having the highest MDRD-based prevalence at 7.9% (95%CI 5.2-11.1%). Within Africa, the pooled MDRD-based prevalence was highest in West Africa [14.6% (95%CI 9.9-20.0%)] and lowest in Southern Africa (3.2%, 95%CI 3.0-3.4%). The heterogeneity observed could be explained by WHO region, comorbid hypertension and diabetes mellitus, but not by gender, hepatitis B or C coinfection, CD4 count or antiretroviral status.

CONCLUSION

CKD is common in HIV-infected people, particularly in Africa. HIV treatment programs need to intensify screening for CKD with added need to introduce global guidelines for CKD identification and treatment in HIV positive patients.

Chronic Kidney Disease and Antiretroviral Therapy in HIV-Positive Individuals: Recent Developments

Chronic kidney disease (CKD) has emerged as an important health concern in HIV-positive individuals. Preventing long-term kidney toxicity from an antiretroviral therapy is therefore critical. Selected antiretroviral agents, especially tenofovir disoproxil fumarate (TDF) and some ritonavir-boosted protease inhibitors (PI/rs), have been associated with increased risk of CKD. However, the CKD risk attributable to these agents is overall small, especially in those with low baseline risk of CKD and normal renal function. CKD risk in HIV-positive individuals can be further minimized by timely identification of those with worsening renal function and discontinuation of potentially nephrotoxic agents. Clinicians can use several monitoring tools, including the D:A:D risk score and routine measurements of estimated glomerular filtration (eGFR) and proteinuria, to identify high-risk individuals who may require an intervention. Tenofovir alafenamide (TAF), a TDF alternative, promises to be safer in terms of TDF-associated kidney and bone toxicity. While the short-term data on TAF does indicate lower eGFR decline and lower risk of proteinuria (vs. TDF), long-term data on renal safety of TAF are still awaited. Promising results have also emerged from recent trials on alternative dual-therapy antiretroviral regimens which exclude the nucleoside(tide) reverse transcriptase class as well as possibly the PI/rs, thereby reducing the drug burden, and possibly the toxicity. However, long-term safety or benefits of these dual-therapy regimens are still unclear and will need to be studied in future prospective studies. Finally, addressing risk factors such as hypertension and diabetes will continue to be important in this population.

Improved kidney function in patients who switch their protease inhibitor from atazanavir or lopinavir to darunavir

Supplemental Digital Content is available in the text

Objective:

Atazanavir (ATV) and lopinavir (LPV) have been associated with kidney disease progression in HIV positive patients, with no data reported for darunavir (DRV). We examined kidney function in patients who switched their protease inhibitor from ATV or LPV to DRV.

Design:

Cohort study.

Methods:

Data were from the UK CHIC study. We compared pre and post switch estimated glomerular filtration rate (eGFR) slopes (expressed in ml/min per 1.73 m² per year) in all switchers and those with rapid eGFR decline (>5 ml/min per 1.73 m² per year) on ATV or LPV. Mixed-effects models were adjusted for age, gender, ethnicity, eGFR at switch and time updated CD4⁺ cell count, HIV RNA and cumulative tenofovir (tenofovir disoproxil fumarate) exposure.

Results:

Data from 1430 patients were included. At the time of switching to DRV, median age was 45 years, 79% were men, 76% had an undetectable viral load, and median eGFR was 93 ml/min per 1.73 m². Adjusted mean (95% confidence interval) pre and post switch eGFR slopes were −0.84 (−1.31, −0.36) and 1.23 (0.80, 1.66) for ATV (P < 0.001), and −0.57 (−1.09, −0.05) and 0.62 (0.28, 0.96) for LPV (P < 0.001). Stable or improved renal function was observed in patients with rapid eGFR decline on ATV or LPV who switched to DRV [−15.27 (−19.35, −11.19) and 3.72 (1.78, 5.66), P < 0.001 for ATV, −11.93 (−14.60, −9.26) and 0.87 (−0.54, 2.27), P < 0.001 for LPV]. Similar results were obtained if participants who discontinued tenofovir disoproxil fumarate at the time of switch were excluded.

Conclusions:

We report improved kidney function in patients who switched from ATV or LPV to DRV, suggesting that DRV may have a more favourable renal safety profile.

Estimation of renal function by CKD-EPI versus MDRD in a cohort of HIV-infected patients: a cross-sectional analysis

Background

Accurately determining renal function is essential for clinical management of HIV patients. Classically, it has been evaluated by estimating glomerular filtration rate (eGFR) with the MDRD-equation, but today there is evidence that the new Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation has greater diagnostic accuracy. To date, however, little information exists on patients with HIV-infection. This study aimed to evaluate eGFR by CKD-EPI vs. MDRD equations and to stratify renal function according to KDIGO guidelines.

Methods

Cross-sectional, single center study including adult patients with HIV-infection.

Results

Four thousand five hundred three patients with HIV-infection (864 women; 19%) were examined. Median age was 45 years (IQR 37–52), and median baseline creatinine was 0.93 mg/dL (IQR 0.82–1.05). A similar distribution of absolute measures of eGFR was found using both formulas (p = 0.548). Baseline median eGFR was 95.2 and 90.4 mL/min/1.73 m² for CKD-EPI and MDRD equations (p < 0.001), respectively. Of the 4503 measurements, 4109 (91.2%) agreed, with a kappa index of 0.803. MDRD classified 7.3% of patients as “mild reduced GFR” who were classified as “normal function” with CKD-EPI. Using CKD-EPI, it was possible to identify “normal function” (>90 mL/min/1.73 m²) in 73% patients and “mild reduced GFR” (60–89 mL/min/1.73 m²) in 24.3% of the patients, formerly classified as >60 mL/min/1.73 m² with MDRD.

Conclusions

There was good correlation between CKD-EPI and MDRD. Estimating renal function using CKD-EPI equation allowed better staging of renal function and should be considered the method of choice. CKD-EPI identified a significant proportion of patients (24%) with mild reduced GFR (60–89 mL/min/1.73 m²).

Treatment-limiting renal tubulopathy in patients treated with tenofovir disoproxil fumarate

OBJECTIVES

Tenofovir disoproxil fumarate (TDF) is widely used in the treatment or prevention of HIV and hepatitis B infection. TDF may cause renal tubulopathy in a small proportion of recipients. We aimed to study the risk factors for developing severe renal tubulopathy.

METHODS

We conducted an observational cohort study with retrospective identification of cases of treatment-limiting tubulopathy during TDF exposure. We used multivariate Poisson regression analysis to identify risk factors for tubulopathy, and mixed effects models to analyse adjusted estimated glomerular filtration rate (eGFR) slopes.

RESULTS

Between October 2002 and June 2013, 60 (0.4%) of 15,983 patients who had received TDF developed tubulopathy after a median exposure of 44.1 (IQR 20.4, 64.4) months. Tubulopathy cases were predominantly male (92%), of white ethnicity (93%), and exposed to antiretroviral regimens that contained boosted protease inhibitors (PI, 90%). In multivariate analysis, age, ethnicity, CD4 cell count and use of didanosine or PI were significantly associated with tubulopathy. Tubulopathy cases experienced significantly greater eGFR decline while receiving TDF than the comparator group (-6.60 [-7.70, -5.50] vs. -0.34 [-0.43, -0.26] mL/min/1.73 m²/year, p < 0.0001).

CONCLUSIONS

Older age, white ethnicity, immunodeficiency and co-administration of ddI and PI were risk factors for tubulopathy in patients who received TDF-containing antiretroviral therapy. The presence of rapid eGFR decline identified TDF recipients at increased risk of tubulopathy.

Polymorphisms associated with renal adverse effects of antiretroviral therapy in a Southern Brazilian HIV cohort

OBJECTIVE

This study evaluated the impact of seven single nucleotide polymorphisms in five candidate genes (ABCB1, ABCC2, ABCC4, SLC22A6, and SLC22A11) in relation to nephrotoxicity associated with highly active antiretroviral therapy (HAART) in HIV-infected individuals.

METHODS

The following single nucleotide polymorphisms were genotyped by real-time PCR: ABCB1 rs1045642, ABCC2 rs717620 and rs2273697, ABCC4 rs1751034 and rs3742106, SLC22A6 rs11568626, and SLC22A11 rs11231809 in 507 HIV-infected patients from the city of Porto Alegre, Southern Brazil, receiving HAART for, at least, 1 year.

RESULTS

From the 507 HIV-infected patients recruited, 19.1% presented a reduction in estimated glomerular filtration rate (eGFR). A total of 16 (3.2%) patients fulfilled the criteria for chronic kidney disease (defined as eGFR<60 ml/min/1.73 m). Individuals carrying at least one T allele of ABCC2 -24 C>T (rs717620) presented lower eGFR than C/C homozygotes (104 ± 22 vs. 108 ± 22 ml/min/1.73 m, independent-samples t-test, P=0.040). In multivariate analysis, the predictors associated with decreased eGFR were time of treatment, tenofovir use, atazanavir/ritonavir use, and carrying one T allele of ABCC2 -24 C>T.

CONCLUSION

Our data support the importance of genetic factors in the etiology of nephrotoxicity in patients treated with HAART. Studies to verify treatment implications of genotyping before HAART initiation may be advisable to guide the selection of an appropriate antiretroviral therapy regimen.

[The role of immune factors in the progression of chronic kidney diseases in HIV infection]

AIM

To determine the significance of immune factors in the pathogenesis of kidney injuries in HIV infection, by investigating the cellular and cytokine components of an immune response.

MATERIALS AND METHODS

Thirty HIV-infected patients (mean age 31.7±6.2 years) with chronic kidney disease (CKD) were examined. A comparison group consisted of 10 HIV-infected patients without signs of kidney injury. A control group included 24 healthy individuals to analyze immune status and 15 people to estimate the normal values of the cytokine composition. The cellular composition of lymphocytes on a typical immunogram was determined on a flow cytofluorometer; the serum concentrations of cytokines were measured on a multichannel photometer.

RESULTS

The HIV-infected patients with kidney injury displayed significant reductions in the absolute (0.2·109/l and 0.4·109/l, respectively; р=0.015) and relative (14.75 and 22%, respectively; р=0.005) counts of CD3+/CD4+ cells and in the immunoregulatory index (0.2 and 0.4, respectively; р=0.014) as compared to those in HIV-infected patients without kidney disease (р≤0.05) with a rise in the number of cytotoxic T cells (CD3+/CD8+). The HIV-infected patients showed a preponderance of immunosuppressive cytokine compositions, as indicated by the high levels of transforming growth factor-β (a more than 50-fold increase) and by a statistically significant rise in the level of tumor necrosis factor-α (TNF-α) (with CD4+ lymphocyte counts more or less than 200 cells/µl - 19.0 and 24.2 pg/ml, respectively; p=0.017; with HIV RNA levels more and less than 100,000 copies/ml - 24.4 and 19.7 pg/ml, respectively; p=0.012).

CONCLUSION

The HIV-infected patients with CKD developed kidney injury in the presence of a more pronounced decrease in blood T helper lymphocyte subpopulation levels with a predominance of proinflammatory and immunosuppressive responses. TNF-α in combination with immunosuppression and high viral loads was established to play a leading role in the development of kidney injury in HIV infection.

Clinical characteristics and outcomes of HIV-associated immune complex kidney disease

BACKGROUND

The pathogenesis and natural history of HIV-associated immune complex kidney disease (HIVICK) is not well understood. Key questions remain unanswered, including the role of HIV infection and replication in disease development and the efficacy of antiretroviral therapy (ART) in the prevention and treatment of disease.

METHODS

In this multicentre study, we describe the renal pathology of HIVICK and compare the clinical characteristics of patients with HIVICK with those with IgA nephropathy and HIV-associated nephropathy (HIVAN). Poisson regression models were used to identify risk factors for each of these pathologies.

RESULTS

Between 1998 and 2012, 65 patients were diagnosed with HIVICK, 27 with IgA nephropathy and 70 with HIVAN. Black ethnicity and HIV RNA were associated with HIVICK, receipt of ART with IgA nephropathy and black ethnicity and CD4 cell count with HIVAN. HIVICK was associated with lower rates of progression to end-stage kidney disease compared with HIVAN and IgA nephropathy (P < 0.0001). Patients with HIVICK who initiated ART and achieved suppression of HIV RNA experienced improvements in estimated glomerular filtration rate and proteinuria.

CONCLUSIONS

These findings suggest a pathogenic role for HIV replication in the development of HIVICK and that ART may improve kidney function in patients who have detectable HIV RNA at the time of HIVICK diagnosis. Our data also suggest that IgA nephropathy should be viewed as a separate entity and not included in the HIVICK spectrum.

Effects on vitamin D, bone and the kidney of switching from fixed-dose tenofovir disoproxil fumarate/emtricitabine/efavirenz to darunavir/ritonavir monotherapy: a randomized, controlled trial (MIDAS)

BACKGROUND

Efavirenz (EFV) has been associated with reductions in vitamin D (25[OH]D) and tenofovir (TDF) with increased bone turnover, reductions in bone mineral density (BMD) and renal tubular dysfunction. We hypothesized that switching from fixed-dose TDF/emtricitabine (FTC)/EFV to darunavir/ritonavir monotherapy (DRV/r) might increase 25(OH)D and BMD, and improve renal tubular function.

METHODS

Subjects with HIV RNA <50 copies/ml on TDF/FTC/EFV for ≥6 months were randomized 1:1 to ongoing TDF/FTC/EFV or DRV/r (800/100 mg once daily) for 48 weeks. The primary end point was change from baseline in 25(OH)D at week 48. Secondary end points included changes in BMD, bone turnover markers and renal tubular function.

RESULTS

A total of 64 subjects (86% male, 66% white, mean [sd] CD4(+) T-cell count 537.3 [191.5]/mm(3)) were analysed. After adjustment for baseline 25(OH)D and demographics, at week 48 DRV/r monotherapy was associated with a +3.6 (95% CI 0.6, 6.6) ng/ml increase in 25(OH)D compared to TDF/FTC/EFV (P=0.02). DRV/r monotherapy was associated with an increase in BMD (+2.9% versus -0.003% at the neck of femur and +2.6% versus +0.008% at the lumbar spine for DRV/r versus TDF/FTC/EFV; P<0.05 for all) and reductions in bone biomarkers compared with those remaining on TDF/FTC/EFV. No significant difference in renal tubular function was observed. Reasons for discontinuation in the DRV/r arm included side effects (n=4) and viral load rebound (n=3), all of which resolved with DRV/r discontinuation or regimen intensification.

CONCLUSIONS

Switching from TDF/FTC/EFV to DRV/r in patients with suppressed HIV RNA resulted in significant improvements in 25(OH)D and bone biomarkers, and a 2-3% increase in BMD.

Effects of renal tubular dysfunction on bone in tenofovir-exposed HIV-positive patients

OBJECTIVES

Tenofovir disoproxil fumarate (TDF) may cause renal tubular dysfunction (RTD) and reduce bone mineral density (BMD). We examined the relationship between RTD and BMD in TDF-exposed HIV-positive men.

DESIGN AND METHODS

We analysed urinary retinol-binding protein/creatinine ratio (RBPCR) and fractional excretion of phosphate (FEPO4) to quantify RTD in a cross-sectional sample of randomly selected HIV-positive men at a single tertiary outpatient clinic. BMD at the lumbar spine and hip was measured by dual-energy X-ray absorptiometry. Multivariate logistic regression was used to analyse factors associated with RTD, and linear regression to examine the relationship between RTD and BMD.

RESULTS

Of 293 men (mean age 48 years, 94% White ethnicity, median TDF exposure 2.1 years), 22.5% had RBPCR-defined RTD and 12.3% had FEPO4-defined RTD. We observed a negative correlation between RBPCR and BMD at the spine (β -0.2, P = 0.002) and hip (total: β -0.1, P = 0.02; femoral neck: β -0.1, P = 0.02), but not between FePO4 and BMD. In multivariable analyses, RTD defined by more than five-fold elevations in RBPCR was associated with significantly lower BMD of the spine.

CONCLUSION

In HIV-positive patients receiving TDF-containing antiretroviral therapy, RTD was associated with lower BMD of the spine in HIV-positive men. RBPCR quantification may identify patients at increased risk of TDF-associated BMD loss.

Kidney dysfunction associated with tenofovir exposure in human immunodeficiency virus-1-infected Taiwanese patients

BACKGROUND/PURPOSE

Tenofovir disoproxil fumarate (TDF) is associated with kidney tubular dysfunction, for which the risk may vary among patients of different ethnicities. Data are limited, however, on the association between renal function changes and TDF exposure in human immunodeficiency virus (HIV)-infected Taiwanese patients.

METHODS

Medical records of HIV-infected Taiwanese patients seeking HIV care at a university hospital from 2011 to 2014 were reviewed. The change of estimated glomerular filtration rate (eGFR) was compared between patients not receiving combination antiretroviral therapy (cART) and those starting cART with or without TDF. The determinants of annual eGFR changes and factors associated with greater annual eGFR decline in TDF-exposed patients were explored.

RESULTS

A total of 775 patients were included: 140 were cART-naïve, 393 received TDF-containing cART, and 242 received cART without TDF. Compared with cART-naïve patients, the annual eGFR decline was greater in TDF-exposed patients (0.57 ± 8.6 mL/min/1.73 m² and 2.7 ± 8.9 mL/min/1.73 m², p = 0.012). The annual eGFR decline between patients receiving cART with or without TDF was similar (2.7 ± 8.9 mL/min/1.73 m² and 1.8 ± 8.3 mL/min/1.73 m², p = 0.567). Diabetes was associated with worsening eGFR decline in all studied patients. TDF exposure correlated with an additional annual eGFR decline of 2.73 mL/min/1.73 m² (95% confidence interval 0.139-5.326, p = 0.039) in patients with CD4 count < 350 cells/μL. Among TDF-exposed patients, the factors associated with annual eGFR decline of > 3 mL/min/1.73 m² were higher baseline eGFR and lower CD4 counts.

CONCLUSION

Among HIV-infected Taiwanese patients, cART exposure correlated with the decline of renal function. However, TDF-exposed patients are more likely to have prominent eGFR decline, especially those with higher baseline eGFR, advanced HIV disease, and diabetes.

Proximal tubular dysfunction and kidney injury associated with tenofovir in HIV patients: a case series

Background

Tenofovir disoproxil fumarate (TDF) may cause acute kidney injury and proximal tubular dysfunction. However, no detailed studies document urinary phosphate wasting as a marker of TDF-induced tubulopathy.

Methods

Records of HIV-infected patients with presumed TDF toxicity were reviewed. We describe the characteristics and clinical course of 15 patients who had documented elevated (>20%) fractional excretion of phosphate (FEphos).

Results

Patients were predominantly Caucasian and male (73 and 80%, respectively), with a mean age of 56 years (range 38–76). Of the 15 patients, 11 had a estimated glomerular filtration rate (eGFR) of >90 mL/min/1.73² at time of TDF initiation. The mean duration of TDF therapy prior to diagnosis of TDF toxicity was 64 months. Mean FEphos was 34% (range 20–62). The mean eGFR at TDF initiation was 104 mL/min/1.73 m² [standard deviation (SD) 17.0] with a gradual decline to 69 mL/min/1.73 m² (SD 19.0) by the time of TDF discontinuation. Of 10 patients with repeated FEphos after TDF discontinuation, 9 had improvement of their FEphos. Of these individuals, 6 had normalization of their FEphos. Estimated GFR improved in 12 patients after discontinuation of TDF, though importantly, none returned to their baseline eGFR.

Conclusions

Urinary phosphate wasting is a sensitive marker for TDF-induced proximal tubulopathy and is associated with unrecognized and permanent renal function decline. Tubular dysfunction can develop after years of TDF therapy in those with normal kidney function at the time of drug initiation. This suggests that continuing vigilance be maintained in all those on TDF.

Monitoring of kidney function in HIV-positive patients

HIV-positive patients are at increased risk of developing chronic kidney disease. Although guidelines recommend regular monitoring of renal function in individuals living with HIV, the optimal frequency remains to be defined. In this review, we discuss the renal syndromes that may be identified at an earlier stage via routine assessment of kidney function, and provide guidance in terms of the frequency of monitoring, the most useful tests to perform, and their clinical significance. Specifically, we address whether annual monitoring of kidney function is appropriate for the majority of HIV-positive patients.

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.

End-stage kidney disease and kidney transplantation in HIV-positive patients: an observational cohort study

End-stage kidney disease (ESKD) is a major complication of HIV infection. We observed a 3.8-fold increase in ESKD prevalence among black patients in the UK CHIC cohort during the 12-year study period. As of 2005, 107 patients had an ESKD diagnosis, 69 of whom (64%) were considered suitable for kidney transplantation (KT) and 34 (32%) had received a KT. Survival was similar for KT recipients and those awaiting KT (85% and 89% at 5 years, respectively; P = 0.53). Our results endorse the use of KT to manage ESKD in HIV-positive patients.

Comorbidities among the HIV-infected patients aged 40 years or older in Taiwan

Background

With the widespread use of combination antiretroviral therapy (cART), life expectancy of HIV-infected patients has significantly prolonged. An increasing number of HIV-infected patients are aging and concurrent use of medications are not uncommon for management of metabolic complications and cardiovascular diseases related to aging and prolonged exposure to cART.

Methods

We reviewed medical records of all HIV-infected patients aged 40 years or older who had been followed at a university hospital for HIV care in Taiwan between January and December 2013. A standardized case record form was used to collect information on demographics and clinical characteristics, comorbidity, cART, and concurrent medications.

Results

During the study period, 610 patients aged 40 to 49 years (mean, 44.1) and 310 aged 50 years or older (mean, 58.8) sought HIV care at this hospital. Compared with patients aged 40 to 49 years, those aged 50 years or older were significantly more likely to be female (15.9% vs 3.8%); to have received cART (97.7% vs 94.8%) and a lower plasma HIV RNA load (1.6 vs 1.7 log₁₀ copies/ml); and to have diabetes mellitus (18.4% vs 4.6%), hypertension (31.0% vs 10.8%), hyperlipidemia (29.4% vs 11.6%), coronary artery disease (6.8% vs 0.5%), and an estimated glomerular filtration rate <60 ml/min/1.73 m² (11.5% vs 2.7%); and were significantly less likely to have syphilis. Other than HIV infection, patients aged 50 years or older were more likely to have been receiving two or more concurrent medications than those aged 40 to 49 years (22.9% vs 6.4%).

Conclusions

Our findings show a significant proportion of the HIV-infected patients aged 50 years or older have multiple comorbidities that may increase the risk for cardiovascular and renal complications. Issues of poly-pharmacy among the HIV-infected patients who are aging should be addressed to ensure adherence and minimize drug-drug interactions.

Comparison of renal changes with lopinavir/ritonavir plus raltegravir or tenofovir/emtricitabine in the PROGRESS study

ABSTRACT 

Aim: To assess renal function changes among 172 treatment-naive subjects treated with lopinavir/ritonavir (LPV/r) plus raltegravir (RAL) or LPV/r plus tenofovir/emtricitabine in the PROGRESS study, a prospective, randomized controlled trial. Patients & methods: Serum creatinine, creatinine clearance and chronic kidney disease category were compared between groups. Results: Mean change from baseline to week 96 in creatinine clearance was smaller with LPV/r plus RAL versus LPV/r plus tenofovir/emtricitabine (-1.4 vs -7.3 ml/min; p = 0.035). Chronic kidney disease category improvement was more frequent and the mean increase in serum creatinine was smaller for the LPV/r plus RAL group. Differences in estimated renal function were also detected when the analysis was performed according to baseline demographics. Conclusion: Smaller renal function declines were observed with LPV/r plus RAL. The results from this study warrant further evaluation of the renal safety profile of nucleotide reverse transcriptase inhibitor-sparing regimens.

Development of a definition for Rapid Progression (RP) of renal function in HIV-positive persons: the D:A:D study

Background

No consensus exists on how to define abnormally rapid deterioration in renal function (Rapid Progression, RP). We developed an operational definition of RP in HIV-positive persons with baseline estimated glomerular filtration rate (eGFR) >90 ml/min/1.73 m² (using Cockcroft Gault) in the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study from 2004 to 2011.

Methods

Two definitions were evaluated; RP definition A: An average eGFR decline (slope) ≥5 ml/min/1.73 m²/year over four years of follow-up with ≥3 eGFR measurements/year, last eGFR <90 ml/min/1.73 m² and an absolute decline ≥5 ml/min/1.73 m²/year in two consecutive years. RP definition B: An absolute annual decline ≥5 ml/min/1.73 m²/year in each year and last eGFR <90 ml/min/1.73 m². Sensitivity analyses were performed considering two and three years’ follow-up. The percentage with and without RP who went on to subsequently develop incident chronic kidney disease (CKD; 2 consecutive eGFRs <60 ml/min/1.73 m² and 3 months apart) was calculated.

Results

22,603 individuals had baseline eGFR ≥90 ml/min/1.73 m². 108/3655 (3.0%) individuals with ≥4 years’ follow-up and ≥3 measurements/year experienced RP under definition A; similar proportions were observed when considering follow-up periods of three (n=195/6375; 3.1%) and two years (n=355/10756; 3.3%). In contrast under RP definition B, greater proportions experienced RP when considering two years (n=476/10756; 4.4%) instead of three (n=48/6375; 0.8%) or four (n=15/3655; 0.4%) years’ follow-up. For RP definition A, 13 (12%) individuals who experienced RP progressed to CKD, and only (21) 0.6% of those without RP progressed to CKD (sensitivity 38.2% and specificity 97.4%); whereas for RP definition B, fewer RP individuals progressed to CKD.

Conclusions

Our results suggest using three years’ follow-up and at least two eGFR measurements per year is most appropriate for a RP definition, as it allows inclusion of a reasonable number of individuals and is associated with the known risk factors. The definition does not necessarily identify all those that progress to incident CKD, however, it can be used alongside other renal measurements to early identify and assess those at risk of developing CKD. Future analyses will use this definition to identify other risk factors for RP, including the role of antiretrovirals.

Deteriorating renal function and clinical outcomes in HIV-positive persons

OBJECTIVES

To determine the relationship between measures of renal function [current estimated glomerular filtration rate (eGFR) and proportion of follow-up with a low eGFR (%FU ≤60 ml/min)] and fatal/ nonfatal AIDS, non-AIDS events and all-cause mortality.

DESIGN

An observational, longitudinal cohort study of 12 155 persons from EuroSIDA.

METHODS

Persons with at least one eGFR measurement after 1 January 2004, using the CKD-EPI formula, were included. Poisson regression analyses were used to determine whether current eGFR or %FU of 60 ml/min or less were independent prognostic markers for clinical events.

RESULTS

During 61 425 person-years of follow-up (PYFU), the crude incidence of deaths was 11.1/1000 PYFU [95% confidence interval (CI) 10.0-12.1] at current eGFR more than 90 ml/min and 199.6 (95% CI 1144.3-254.3/1000 PYFU) when current eGFR was 30 ml/min or less. Corresponding figures for AIDS were 12.2 (11.1-13.3) and 63.9 (36.5-103.7) and for non-AIDS were 16.0 (14.8-17.3) and 203.6 (147.7-259.5). After adjustment, current eGFR of 30 ml/min or less was a strong predictor of death [adjusted incidence rate ratios (aIRR) 4.35; 95% CI 3.20-5.91] and non-AIDS events (3.63; 95% CI 2.57-5.13), although the relationship with AIDS was less strong (1.45; 95% CI 1.01-2.08). After adjustment, %FU of 60 ml/min or less was associated with a 22% increased incidence of death (aIRR 1.22 per 10% longer; 95% CI 1.18-1.27), a 13% increased incidence of non-AIDS events (95% CI 1.08-1.18) and a 15% increased incidence of AIDS events (95% CI 1.06-1.24).

CONCLUSION

Both current eGFR and %FU of 60 ml/min or less were associated with death and non-AIDS events in HIV-positive persons. Our findings highlight the association between underlying renal dysfunction and morbidity and mortality in HIV infection, although reverse causality cannot be excluded.

Incomplete reversibility of estimated glomerular filtration rate decline following tenofovir disoproxil fumarate exposure

Background. Tenofovir disoproxil fumarate (TDF) has been linked to renal impairment, but the extent to which this impairment is reversible is unclear. We aimed to investigate the reversibility of renal decline during TDF therapy.

Methods. Cox proportional hazards models assessed factors associated with discontinuing TDF in those with an exposure duration of >6 months. In those who discontinued TDF therapy, linear piecewise regression models estimated glomerular filtration rate (eGFR) slopes before initiation of, during, and after discontinuation of TDF therapy. Factors associated with not achieving eGFR recovery 6 months after discontinuing TDF were assessed using multivariable logistic regression.

Results. We observed declines in the eGFR during TDF exposure (mean slopes, −15.7 mL/minute/1.73 m²/year [95% confidence interval {CI}, −20.5 to −10.9] during the first 3 months and −3.1 mL/minute/1.73 m²/year [95% CI, −4.6 to −1.7] thereafter) and evidence of eGFR increases following discontinuation of TDF therapy (mean slopes, 12.5 mL/minute/1.73 m²/year [95% CI, 8.9–16.1] during the first 3 months and 0.8 mL/minute/1.73 m²/year [95% CI, .1–1.5] thereafter). Following TDF discontinuation, 38.6% of patients with a decline in the eGFR did not experience recovery. A higher eGFR at baseline, a lower eGFR after discontinuation of TDF therapy, and more-prolonged exposure to TDF were associated with an increased risk of incomplete recovery 6 months after discontinuation of TDF therapy.

Conclusions. This study shows that a decline in the eGFR during TDF therapy was not fully reversible in one third of patients and suggests that prolonged TDF exposure at a low eGFR should be avoided.

The validity of the modification of diet in renal disease formula in HIV-infected patients: a systematic review

RATIONALE, AIMS AND OBJECTIVES

Renal dysfunction is highly prevalent in HIV-infected patients and may require dose adjustment of renally excreted antiretroviral drugs. The Modification of Diet in Renal Disease (MDRD)-4 formula is frequently used in daily practice to estimate patients' renal function. The aim of this systematic review was to assess the validity of the MDRD-4 formula in HIV-infected patients.

METHOD

A systematic search in Pubmed and EMBASE was done to identify studies which compared MDRD-4 with measured glomerular filtration rate (mGFR) in HIV-infected patients.

RESULTS

Five studies were included, which provided data from 464 HIV-infected patients with mean mGFR ranging from 87 to 118 ml/min/1.73 m(2). In all studies, results from the MDRD-4 gave an underestimation of the mGFR. Mean bias ((MDRD-4) - mGFR) ranged from -6 to -11 ml/min/1.73 m(2) across studies. The accuracy expressed in terms of P 30 ranged from 64 to 89 %.

CONCLUSIONS

The MDRD-4 formula is as valid in HIV-positive as in HIV-negative patients. Because the available studies comprised mainly HIV-infected patients with mildly impaired to good renal function (GFR ≥ 60 ml/min/1.73 m(2)), more research is needed to validate the MDRD-4 formula in HIV-infected patients with moderate to severe renal impairment.

A comparison of estimated glomerular filtration rates using Cockcroft-Gault and the Chronic Kidney Disease Epidemiology Collaboration estimating equations in HIV infection

OBJECTIVES

The aim of this study was to determine whether the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)- or Cockcroft-Gault (CG)-based estimated glomerular filtration rates (eGFRs) performs better in the cohort setting for predicting moderate/advanced chronic kidney disease (CKD) or end-stage renal disease (ESRD).

METHODS

A total of 9521 persons in the EuroSIDA study contributed 133 873 eGFRs. Poisson regression was used to model the incidence of moderate and advanced CKD (confirmed eGFR < 60 and < 30 mL/min/1.73 m(2) , respectively) or ESRD (fatal/nonfatal) using CG and CKD-EPI eGFRs.

RESULTS

Of 133 873 eGFR values, the ratio of CG to CKD-EPI was ≥ 1.1 in 22 092 (16.5%) and the difference between them (CG minus CKD-EPI) was ≥ 10 mL/min/1.73 m(2) in 20 867 (15.6%). Differences between CKD-EPI and CG were much greater when CG was not standardized for body surface area (BSA). A total of 403 persons developed moderate CKD using CG [incidence 8.9/1000 person-years of follow-up (PYFU); 95% confidence interval (CI) 8.0-9.8] and 364 using CKD-EPI (incidence 7.3/1000 PYFU; 95% CI 6.5-8.0). CG-derived eGFRs were equal to CKD-EPI-derived eGFRs at predicting ESRD (n = 36) and death (n = 565), as measured by the Akaike information criterion. CG-based moderate and advanced CKDs were associated with ESRD [adjusted incidence rate ratio (aIRR) 7.17; 95% CI 2.65-19.36 and aIRR 23.46; 95% CI 8.54-64.48, respectively], as were CKD-EPI-based moderate and advanced CKDs (aIRR 12.41; 95% CI 4.74-32.51 and aIRR 12.44; 95% CI 4.83-32.03, respectively).

CONCLUSIONS

Differences between eGFRs using CG adjusted for BSA or CKD-EPI were modest. In the absence of a gold standard, the two formulae predicted clinical outcomes with equal precision and can be used to estimate GFR in HIV-positive persons.

Kidney transplantation in HIV-positive adults: the UK experience

HIV-positive patients are at increased risk of end-stage kidney disease (ESKD). Kidney transplantation (KT) is an established treatment modality for ESKD in the general population. Recent data have confirmed the feasibility of kidney transplantation in HIV-positive patients, and kidney transplantation is increasingly offered to ESKD patients with well-controlled HIV infection. We report clinical outcomes in a national cohort study of kidney transplantation in HIV-positive patients. In all, 35 HIV-positive KT recipients who had undergone KT up to December 2010 (66% male, 74% black ethnicity) were identified; the median CD4 cell count was 366, all had undetectable HIV RNA levels at kidney transplantation, and 44% received a kidney from a live donor. Patient survival at 1 and 3 years was 91.3%, and graft survival 91.3% and 84.7%, respectively. At one-year post-kidney transplantation, the cumulative incidence of acute rejection was 48%, and the median (IQR) eGFR was 64 (46, 78) mL/min/1.73 m(2). Although HIV viraemia and HIV disease progression were uncommon, renal complications were relatively frequent. Our study corroborates the feasibility of kidney transplantation in HIV-positive patients. The high rates of acute rejection suggest that the optimal immune suppression strategy in this population remains to be refined.

Aging with HIV: an overview of an urban cohort in Rio de Janeiro (Brazil) across decades of life

The introduction of highly active antiretroviral therapy during the 1990s was crucial to the decline in the rates of morbidity and death related to the acquired immunodeficiency syndrome (AIDS) and turned human immunodeficiency virus (HIV) infection into a chronic condition. Consequently, the HIV/AIDS population is becoming older. The aim of this study was to describe the immunological, clinical and comorbidity profile of an urban cohort of patients with HIV/AIDS followed up at Instituto de Pesquisa Clinica Evandro Chagas, Oswaldo Cruz Foundation in Rio de Janeiro, Brazil. Retrospective data from 2307 patients during January 1st, 2008 and December 31st, 2008 were collected. For continuous variables, Cuzick's non-parametric test was used. For categorical variables, the Cochran–Armitage non-parametric test for tendency was used. For all tests, the threshold for statistical significance was set at 5%. In 2008, 1023 (44.3%), 823 (35.7%), 352 (15.3%) and 109 (4.7%) were aged 18–39, 40–49, 50–59 and ≥60 years-old, respectively. Older and elderly patients (≥40 years) were more likely to have viral suppression than younger patients (18–39 years) (p < 0.001). No significant difference in the latest CD4⁺ T lymphocyte count in the different age strata was observed, although elderly patients (≥ 50 years) had lower CD4⁺ T lymphocyte nadir (p < 0.02). The number of comorbidities increased with age and the same pattern was observed for the majority of the comorbidities, including diabetes mellitus, dyslipidemia, hypertension, cardiovascular diseases, erectile dysfunction, HCV, renal dysfunction and also for non-AIDS-related cancers (p < 0.001). With the survival increase associated to successful antiretroviral therapy and with the increasing new infections among elderly group, the burden associated to the diagnosis and treatment of the non-AIDS related HIV comorbidities will grow. Longitudinal studies on the impact of aging on the HIV/AIDS population are still necessary, especially in resource-limited countries.

Renal impairment is associated with coronary heart disease in HIV-positive men

BACKGROUND

Chronic kidney disease is a risk factor for coronary heart disease (CHD). The association between renal impairment and CHD in HIV-positive patients remains poorly described.

OBJECTIVE

To describe the CHD incidence in a cohort of HIV-positive patients and to examine the relationship between reduced estimated glomerular filtration rate (eGFR) and incident CHD.

METHODS

We studied 7,828 HIV-positive patients who were followed up at 3 South London clinics between January 2004 and December 2009. CHD events were identified from electronic records and through elevated troponin levels. Multivariate Poisson regression analysis was used to identify factors associated with CHD among HIV-positive men.

RESULTS

The incidence of CHD among men was 1.2 (95% CI, 0.8-1.8) per 1,000 person-years of follow-up, with 28 patients (0.4%) having experienced 32 CHD events. In adjusted analyses, older age (incidence rate ratios [IRR], 2.81; 95% CI, 1.51-5.25) and hepatitis C virus (HCV) status (IRR, 3.94; 95% CI, 1.00-15.5) were significantly associated with CHD. Although eGFR as a continuous variable was not associated with CHD, an eGFR <75 mL/min remained associated with incident CHD (IRR, 4.30; 95% CI, 1.33-14.5) after adjustment for age. No association between CHD and abacavir exposure was observed (IRR, 0.94; 95% CI, 0.30-2.99).

CONCLUSIONS

The incidence of CHD in this ethnically diverse cohort was low. Our data suggest that impaired renal function identifies patients at increased risk of CHD events in whom management of traditional CHD risk factors should be prioritized.

Performance of creatinine and cystatin C GFR estimating equations in an HIV-positive population on antiretrovirals

OBJECTIVE

To evaluate the performance of Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine, cystatin C, and creatinine-cystatin C estimating equations in HIV-positive patients.

METHODS

We evaluated the performance of the Modification of Diet in Renal Disease (MDRD) Study and CKD-EPI creatinine 2009, CKD-EPI cystatin C 2012, and CKD-EPI creatinine-cystatin C 2012 glomerular filtration rate (GFR) estimating equations compared with GFR measured using plasma clearance of iohexol in 200 HIV-positive patients on stable antiretroviral therapy. Creatinine and cystatin C assays were standardized to certified reference materials.

RESULTS

Of the 200 participants, median (IQR) CD4 count was 536 (421) and 61% had an undetectable HIV viral load. Mean (SD) measured GFR (mGFR) was 87 (26) mL/min per 1.73 m. All CKD-EPI equations performed better than the MDRD Study equation. All 3 CKD-EPI equations had similar bias and precision. The cystatin C equation was not more accurate than the creatinine equation. The creatinine-cystatin C equation was significantly more accurate than the cystatin C equation, and there was a trend toward greater accuracy than the creatinine equation. Accuracy was equal or better in most subgroups with the combined equation compared to either alone.

CONCLUSIONS

The CKD-EPI cystatin C equation does not seem to be more accurate than the CKD-EPI creatinine equation in patients who are HIV-positive, supporting the use of the CKD-EPI creatinine equation for routine clinical care for use in North American populations with HIV. The use of both filtration markers together as a confirmatory test for decreased estimated GFR based on creatinine in individuals who are HIV-positive requires further study.

Renal dysfunction in the setting of HIV/AIDS

Antiretroviral therapy has been immensely successful in reducing the incidence of opportunistic infections and death after HIV infection. This has resulted in heightened interest in noninfectious comorbidities including kidney disease. Although HIV-associated nephropathy, the most ominous kidney disease related to the direct effects of HIV, may be prevented and treated with antiretrovirals, kidney disease remains an important issue in this population. In addition to the common risk factors for kidney disease of diabetes mellitus and hypertension, HIV-infected individuals have a high prevalence of other risk factors, including hepatitis C and exposure to antiretrovirals and other medications. Therefore, the differential diagnosis is vast. Early identification (through efficient screening) and prompt treatment of kidney disease in HIV-infected individuals are critical to lead to better outcomes. This review focuses on clinical and epidemiological issues, treatment strategies (including dialysis and kidney transplantation), and recent advances among kidney disease in the HIV population.

Association between tenofovir exposure and reduced kidney function in a cohort of HIV-positive patients: results from 10 years of follow-up

BACKGROUND

Some studies have shown that tenofovir disoproxil fumarate (TDF), a drug widely used in highly active antiretroviral therapy, is associated with kidney dysfunction, but the magnitude of the effect and its clinical impact is still being debated. Our objective was to evaluate the association between long-term TDF exposure and kidney dysfunction in a cohort of 1043 human immunodeficiency virus-positive patients followed up for 10 years and to quantify the loss in estimated glomerular filtration rate (eGFR) in patients exposed to TDF in comparison with those exposed to other antiretroviral therapies.

METHODS

Adjusted hazard ratios (HR) and odds ratios (OR) for the association between TDF and kidney dysfunction (defined as eGFR <90 mL/min/1.73 m(2)) were calculated using the Cox proportional hazards model and generalized estimating equations. Mean loss in eGFR attributable to TDF by cumulative years of exposure was estimated using linear regressions.

RESULTS

Tenofovir exposure increased the risk of kidney dysfunction by 63% (HR, 1.63; 95% confidence interval, 1.26-2.10). The cumulative eGFR loss directly attributable to TDF after 1, 2, 3, and 4 years of TDF exposure was -3.05 (P = .017), -4.05 (P = .000), -2.42 (P = .023), and -3.09 mL/min/1.73 m(2) (P = .119), respectively, which shows that most of the loss occurred during the first years of exposure.

CONCLUSIONS

In this cohort, TDF exposure was associated with reduced kidney function, but the loss in eGFR attributable to TDF is relatively mild in a long-term perspective.

Baseline kidney function as predictor of mortality and kidney disease progression in HIV-positive patients

BACKGROUND

Chronic kidney disease (CKD) is associated with increased all-cause mortality and kidney disease progression. Decreased kidney function at baseline may identify human immunodeficiency virus (HIV)-positive patients at increased risk of death and kidney disease progression.

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

7 large HIV cohorts in the United Kingdom with kidney function data available for 20,132 patients.

PREDICTOR

Baseline estimated glomerular filtration rate (eGFR).

OUTCOMES

Death and progression to stages 4-5 CKD (eGFR <30 mL/min/1.73 m(2) for >3 months) in Cox proportional hazards and competing-risk regression models.

RESULTS

Median age at baseline was 34 (25th-75th percentile, 30-40) years, median CD4 cell count was 350 (25th-75th percentile, 208-520) cells/μL, and median eGFR was 100 (25th-75th percentile, 87-112) mL/min/1.73 m(2). Patients were followed up for a median of 5.3 (25th-75th percentile, 2.0-8.9) years, during which 1,820 died and 56 progressed to stages 4-5 CKD. A U-shaped relationship between baseline eGFR and mortality was observed. After adjustment for potential confounders, eGFRs <45 and >105 mL/min/1.73 m(2) remained associated significantly with increased risk of death. Baseline eGFR <90 mL/min/1.73 m(2) was associated with increased risk of kidney disease progression, with the highest incidence rates of stages 4-5 CKD (>3 events/100 person-years) observed in black patients with eGFR of 30-59 mL/min/1.73 m(2) and those of white/other ethnicity with eGFR of 30-44 mL/min/1.73 m(2).

LIMITATIONS

The relatively small numbers of patients with decreased eGFR at baseline and low rates of progression to stages 4-5 CKD and lack of data for diabetes, hypertension, and proteinuria.

CONCLUSIONS

Although stages 4-5 CKD were uncommon in this cohort, baseline eGFR allowed the identification of patients at increased risk of death and at greatest risk of kidney disease progression.