Associations between hemodialysis access type and clinical outcomes: a systematic review

Clinical practice guidelines recommend an arteriovenous fistula as the preferred vascular access for hemodialysis, but quantitative associations between vascular access type and various clinical outcomes remain controversial. We performed a systematic review of cohort studies to evaluate the associations between type of vascular access (arteriovenous fistula, arteriovenous graft, and central venous catheter) and risk for death, infection, and major cardiovascular events. We searched MEDLINE, EMBASE, and article reference lists and extracted data describing study design, participants, vascular access type, clinical outcomes, and risk for bias. We identified 3965 citations, of which 67 (62 cohort studies comprising 586,337 participants) met our inclusion criteria. In a random effects meta-analysis, compared with persons with fistulas, those individuals using catheters had higher risks for all-cause mortality (risk ratio=1.53, 95% CI=1.41-1.67), fatal infections (2.12, 1.79-2.52), and cardiovascular events (1.38, 1.24-1.54). Similarly, compared with persons with grafts, those individuals using catheters had higher risks for mortality (1.38, 1.25-1.52), fatal infections (1.49, 1.15-1.93), and cardiovascular events (1.26, 1.11-1.43). Compared with persons with fistulas, those individuals with grafts had increased all-cause mortality (1.18, 1.09-1.27) and fatal infection (1.36, 1.17-1.58), but we did not detect a difference in the risk for cardiovascular events (1.07, 0.95-1.21). The risk for bias, especially selection bias, was high. In conclusion, persons using catheters for hemodialysis seem to have the highest risks for death, infections, and cardiovascular events compared with other vascular access types, and patients with usable fistulas have the lowest risk.

Serum levels of phosphorus, parathyroid hormone, and calcium and risks of death and cardiovascular disease in individuals with chronic kidney disease: a systematic review and meta-analysis

CONTEXT

Clinical practice guidelines on the management of mineral and bone disorders due to chronic kidney disease recommend specific treatment target levels for serum phosphorus, parathyroid hormone, and calcium.

OBJECTIVE

To assess the quality of evidence for the association between levels of serum phosphorus, parathyroid hormone, and calcium and risks of death, cardiovascular mortality, and nonfatal cardiovascular events in individuals with chronic kidney disease.

DATA SOURCES

The databases of MEDLINE (1948 to December 2010) and EMBASE (1947 to December 2010) were searched without language restriction. Hand searches also were conducted of the reference lists of primary studies, review articles, and clinical guidelines along with full-text review of any citation that appeared relevant.

STUDY SELECTION

Of 8380 citations identified in the original search, 47 cohort studies (N = 327,644 patients) met the inclusion criteria.

DATA EXTRACTION

The characteristics of study design, participants, exposures, and covariates together with the outcomes of all-cause mortality, cardiovascular mortality, and nonfatal cardiovascular events at different levels of serum phosphorus, parathyroid hormone, and calcium were analyzed within studies. Data were summarized across studies (when possible) using random-effects meta-regression.

DATA SYNTHESIS

The risk of death increased 18% for every 1-mg/dL increase in serum phosphorus (relative risk [RR], 1.18 [95% confidence interval {CI}, 1.12-1.25]). There was no significant association between all-cause mortality and serum level of parathyroid hormone (RR per 100-pg/mL increase, 1.01 [95% CI, 1.00-1.02]) or serum level of calcium (RR per 1-mg/dL increase, 1.08 [95% CI, 1.00-1.16]). Data for the association between serum level of phosphorus, parathyroid hormone, and calcium and cardiovascular death were each available in only 1 adequately adjusted cohort study. Lack of adjustment for confounding variables was not a major limitation of the available studies.

CONCLUSIONS

The evidentiary basis for a strong, consistent, and independent association between serum levels of calcium and parathyroid hormone and the risk of death and cardiovascular events in chronic kidney disease is poor. There appears to be an association between higher serum levels of phosphorus and mortality in this population.

Sodium-glucose cotransporter protein-2 (SGLT-2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists for type 2 diabetes: systematic review and network meta-analysis of randomised controlled trials

OBJECTIVE

To evaluate sodium-glucose cotransporter-2 (SGLT-2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists in patients with type 2 diabetes at varying cardiovascular and renal risk.

DESIGN

Network meta-analysis.

DATA SOURCES

Medline, Embase, and Cochrane CENTRAL up to 11 August 2020.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials comparing SGLT-2 inhibitors or GLP-1 receptor agonists with placebo, standard care, or other glucose lowering treatment in adults with type 2 diabetes with follow up of 24 weeks or longer. Studies were screened independently by two reviewers for eligibility, extracted data, and assessed risk of bias.

MAIN OUTCOME MEASURES

Frequentist random effects network meta-analysis was carried out and GRADE (grading of recommendations assessment, development, and evaluation) used to assess evidence certainty. Results included estimated absolute effects of treatment per 1000 patients treated for five years for patients at very low risk (no cardiovascular risk factors), low risk (three or more cardiovascular risk factors), moderate risk (cardiovascular disease), high risk (chronic kidney disease), and very high risk (cardiovascular disease and kidney disease). A guideline panel provided oversight of the systematic review.

RESULTS

764 trials including 421 346 patients proved eligible. All results refer to the addition of SGLT-2 inhibitors and GLP-1 receptor agonists to existing diabetes treatment. Both classes of drugs lowered all cause mortality, cardiovascular mortality, non-fatal myocardial infarction, and kidney failure (high certainty evidence). Notable differences were found between the two agents: SGLT-2 inhibitors reduced admission to hospital for heart failure more than GLP-1 receptor agonists, and GLP-1 receptor agonists reduced non-fatal stroke more than SGLT-2 inhibitors (which appeared to have no effect). SGLT-2 inhibitors caused genital infection (high certainty), whereas GLP-1 receptor agonists might cause severe gastrointestinal events (low certainty). Low certainty evidence suggested that SGLT-2 inhibitors and GLP-1 receptor agonists might lower body weight. Little or no evidence was found for the effect of SGLT-2 inhibitors or GLP-1 receptor agonists on limb amputation, blindness, eye disease, neuropathic pain, or health related quality of life. The absolute benefits of these drugs vary substantially across patients from low to very high risk of cardiovascular and renal outcomes (eg, SGLT-2 inhibitors resulted in 3 to 40 fewer deaths in 1000 patients over five years; see interactive decision support tool (https://magicevidence.org/match-it/200820dist/#!/) for all outcomes.

CONCLUSIONS

In patients with type 2 diabetes, SGLT-2 inhibitors and GLP-1 receptor agonists reduced cardiovascular and renal outcomes, with some differences in benefits and harms. Absolute benefits are determined by individual risk profiles of patients, with clear implications for clinical practice, as reflected in the BMJ Rapid Recommendations directly informed by this systematic review.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019153180.

Metformin therapy and risk of cancer in patients with type 2 diabetes: systematic review

Aims/Hypothesis

Diabetes treatments were related with either an increased or reduced risk of cancer. There is ongoing debate about a potential protective action of metformin. To summarize evidence on the association between metformin and risk of cancer and cancer mortality in patients with diabetes.

Methods

Data source: MEDLINE and EMBASE (January 1966-April 2012). We selected randomized studies comparing metformin and other hypoglycaemic agents and observational studies exploring the association between exposure to metformin and cancer. Outcomes were cancer mortality, all malignancies and site-specific cancers.

Results

Of 25307 citations identified, 12 randomized controlled trials (21,595 patients) and 41 observational studies (1,029,389 patients) met the inclusion criteria. In observational studies there was a significant association of exposure to metformin with the risk of cancer death [6 studies, 24,410 patients, OR:0.65, 95%CI: 0.53-0.80], all malignancies [18 studies, 561,836 patients, OR:0.73, 95%CI: 0.61-0.88], liver [8 studies, 312,742 patients, OR:0.34; 95%CI: 0.19-0.60] colorectal [12 studies, 871,365 patients, OR:0.83, 95%CI: 0.74–0.92], pancreas [9 studies, 847,248 patients, OR:0.56, 95%CI: 0.36–0.86], stomach [2 studies, 100701 patients, OR:0.83, 95%CI: 0.76–0.91], and esophagus cancer [2 studies, 100694 patients, OR:0.90, 95%CI: 0.83–0.98]. No significant difference of risk was observed in randomized trials. Metformin was not associated with the risk of: breast cancer, lung cancer, ovarian cancer, uterus cancer, prostate cancer, bladder cancer, kidney cancer, and melanoma.

Conclusions/Interpretation

Results suggest that Metformin might be associated with a significant reduction in the risk of cancer and cancer-related mortality. Randomized trials specifically designed to evaluate the efficacy of metformin as an anticancer agent are warranted.

Comparison of Clinical Outcomes and Adverse Events Associated With Glucose-Lowering Drugs in Patients With Type 2 Diabetes: A Meta-analysis

IMPORTANCE

Numerous glucose-lowering drugs are used to treat type 2 diabetes.

OBJECTIVE

To estimate the relative efficacy and safety associated with glucose-lowering drugs including insulin.

DATA SOURCES

Cochrane Library Central Register of Controlled Trials, MEDLINE, and EMBASE databases through March 21, 2016.

STUDY SELECTION

Randomized clinical trials of 24 weeks' or longer duration.

DATA EXTRACTION AND SYNTHESIS

Random-effects network meta-analysis.

MAIN OUTCOMES AND MEASURES

The primary outcome was cardiovascular mortality. Secondary outcomes included all-cause mortality, serious adverse events, myocardial infarction, stroke, hemoglobin A1c (HbA1C) level, treatment failure (rescue treatment or lack of efficacy), hypoglycemia, and body weight.

RESULTS

A total of 301 clinical trials (1,417,367 patient-months) were included; 177 trials (56,598 patients) of drugs given as monotherapy; 109 trials (53,030 patients) of drugs added to metformin (dual therapy); and 29 trials (10,598 patients) of drugs added to metformin and sulfonylurea (triple therapy). There were no significant differences in associations between any drug class as monotherapy, dual therapy, or triple therapy with odds of cardiovascular or all-cause mortality. Compared with metformin, sulfonylurea (standardized mean difference [SMD], 0.18 [95% CI, 0.01 to 0.34]), thiazolidinedione (SMD, 0.16 [95% CI, 0.00 to 0.31]), DPP-4 inhibitor (SMD, 0.33 [95% CI, 0.13 to 0.52]), and α-glucosidase inhibitor (SMD, 0.35 [95% CI, 0.12 to 0.58]) monotherapy were associated with higher HbA1C levels. Sulfonylurea (odds ratio [OR], 3.13 [95% CI, 2.39 to 4.12]; risk difference [RD], 10% [95% CI, 7% to 13%]) and basal insulin (OR, 17.9 [95% CI, 1.97 to 162]; RD, 10% [95% CI, 0.08% to 20%]) were associated with greatest odds of hypoglycemia. When added to metformin, drugs were associated with similar HbA1C levels, while SGLT-2 inhibitors offered the lowest odds of hypoglycemia (OR, 0.12 [95% CI, 0.08 to 0.18]; RD, -22% [-27% to -18%]). When added to metformin and sulfonylurea, GLP-1 receptor agonists were associated with the lowest odds of hypoglycemia (OR, 0.60 [95% CI, 0.39 to 0.94]; RD, -10% [95% CI, -18% to -2%]).

CONCLUSIONS AND RELEVANCE

Among adults with type 2 diabetes, there were no significant differences in the associations between any of 9 available classes of glucose-lowering drugs (alone or in combination) and the risk of cardiovascular or all-cause mortality. Metformin was associated with lower or no significant difference in HbA1C levels compared with any other drug classes. All drugs were estimated to be effective when added to metformin. These findings are consistent with American Diabetes Association recommendations for using metformin monotherapy as initial treatment for patients with type 2 diabetes and selection of additional therapies based on patient-specific considerations.

Effects of statins in patients with chronic kidney disease: meta-analysis and meta-regression of randomised controlled trials

OBJECTIVE

To analyse the benefits and harms of statins in patients with chronic kidney disease (pre-dialysis, dialysis, and transplant populations).

DESIGN

Meta-analysis.

DATA SOURCES

Cochrane Central Register of Controlled Trials, Medline, Embase, and Renal Health Library (July 2006).

STUDY SELECTION

Randomised and quasi-randomised controlled trials of statins compared with placebo or other statins in chronic kidney disease.

DATA EXTRACTION AND ANALYSIS

Two reviewers independently assessed trials for inclusion, extracted data, and assessed trial quality. Differences were resolved by consensus. Treatment effects were summarised as relative risks or weighted mean differences with 95% confidence intervals by using a random effects model.

RESULTS

Fifty trials (30 144 patients) were included. Compared with placebo, statins significantly reduced total cholesterol (42 studies, 6390 patients; weighted mean difference -42.28 mg/dl (1.10 mmol/l), 95% confidence interval -47.25 to -37.32), low density lipoprotein cholesterol (39 studies, 6216 patients; -43.12 mg/dl (1.12 mmol/l), -47.85 to -38.40), and proteinuria (g/24 hours) (6 trials, 311 patients; -0.73 g/24 hour, -0.95 to -0.52) but did not improve glomerular filtration rate (11 studies, 548 patients; 1.48 ml/min (0.02 ml/s), -2.32 to 5.28). Fatal cardiovascular events (43 studies, 23 266 patients; relative risk 0.81, 0.73 to 0.90) and non-fatal cardiovascular events (8 studies, 22 863 patients; 0.78, 0.73 to 0.84) were reduced with statins, but statins had no significant effect on all cause mortality (44 studies, 23 665 patients; 0.92, 0.82 to 1.03). Meta-regression analysis showed that treatment effects did not vary significantly with stage of chronic kidney disease. The side effect profile of statins was similar to that of placebo. Most of the available studies were small and of suboptimal quality; mortality data were provided by a few large trials only.

CONCLUSION

Statins significantly reduce lipid concentrations and cardiovascular end points in patients with chronic kidney disease, irrespective of stage of disease, but no benefit on all cause mortality or the role of statins in primary prevention has been established. Reno-protective effects of statins are uncertain because of relatively sparse data and possible outcomes reporting bias.

Antiviral medications to prevent cytomegalovirus disease and early death in recipients of solid-organ transplants: a systematic review of randomised controlled trials

BACKGROUND

Antiviral prophylaxis is commonly used in recipients of solid-organ transplants with the aim of preventing the clinical syndrome associated with cytomegalovirus infection. We undertook a systematic review to investigate whether this approach affects risks of cytomegalovirus disease and death.

METHODS

Randomised controlled trials of prophylaxis with antiviral medications for cytomegalovirus disease in solid-organ-transplant recipients were identified. Data were combined in meta-analyses by a random-effects model.

FINDINGS

Compared with placebo or no treatment, prophylaxis with aciclovir, ganciclovir, or valaciclovir significantly reduced the risks of cytomegalovirus disease (19 trials, 1981 patients; relative risk 0.42 [95% CI 0.34-0.52]), cytomegalovirus infection (17 trials, 1786 patients; 0.61 [0.48-0.77]), and all-cause mortality (17 trials, 1838 patients; 0.63 [0.43-0.92]), mainly owing to lower mortality from cytomegalovirus disease (seven trials, 1300 patients; 0.26 [0.08-0.78]). Prophylaxis also lowered the risks of disease caused by herpes simplex or zoster virus, bacterial infections, and protozoal infections, but not fungal infection, acute rejection, or graft loss. Meta-regression showed no significant difference in the risk of cytomegalovirus disease or all-cause mortality by organ transplanted or cytomegalovirus serostatus; no conclusions were possible for cytomegalovirus-negative recipients of negative organs. In trials of direct comparisons, ganciclovir was more effective than aciclovir in preventing cytomegalovirus disease. Valganciclovir and intravenous ganciclovir were as effective as oral ganciclovir.

INTERPRETATION

Prophylaxis with antiviral medications reduces the risk of cytomegalovirus disease and associated mortality in recipients of solid-organ transplants. This approach should be used routinely in cytomegalovirus-positive recipients and in cytomegalovirus-negative recipients of organs positive for the virus.

Comparative efficacy and safety of blood pressure-lowering agents in adults with diabetes and kidney disease: a network meta-analysis

BACKGROUND

The comparative efficacy and safety of pharmacological agents to lower blood pressure in adults with diabetes and kidney disease remains controversial. We aimed to investigate the benefits and harms of blood pressure-lowering drugs in this population of patients.

METHODS

We did a network meta-analysis of randomised trials from around the world comparing blood pressure-lowering agents in adults with diabetic kidney disease. Electronic databases (the Cochrane Collaboration, Medline, and Embase) were searched systematically up to January, 2014, for trials in adults with diabetes and kidney disease comparing orally administered blood pressure-lowering drugs. Primary outcomes were all-cause mortality and end-stage kidney disease. We also assessed secondary safety and cardiovascular outcomes. We did random-effects network meta-analysis to obtain estimates for primary and secondary outcomes and we presented these estimates as odds ratios or standardised mean differences with 95% CIs. We ranked the comparative effects of all drugs against placebo with surface under the cumulative ranking (SUCRA) probabilities.

FINDINGS

157 studies comprising 43,256 participants, mostly with type 2 diabetes and chronic kidney disease, were included in the network meta-analysis. No drug regimen was more effective than placebo for reducing all-cause mortality. However, compared with placebo, end-stage renal disease was significantly less likely after dual treatment with an angiotensin-receptor blocker (ARB) and an angiotensin-converting-enzyme (ACE) inhibitor (odds ratio 0·62, 95% CI 0·43-0·90) and after ARB monotherapy (0·77, 0·65-0·92). No regimen significantly increased hyperkalaemia or acute kidney injury, although combined ACE inhibitor and ARB treatment had the lowest rank among all interventions because of borderline increases in estimated risks of these harms (odds ratio 2·69, 95% CI 0·97-7·47 for hyperkalaemia; 2·69, 0·98-7·38 for acute kidney injury).

INTERPRETATION

No blood pressure-lowering strategy prolonged survival in adults with diabetes and kidney disease. ACE inhibitors and ARBs, alone or in combination, were the most effective strategies against end-stage kidney disease. Any benefits of combined ACE inhibitor and ARB treatment need to be balanced against potential harms of hyperkalaemia and acute kidney injury.

FUNDING

Canterbury Medical Research Foundation, Italian Medicines Agency.

Aspirin for primary prevention of cardiovascular events in people with diabetes: meta-analysis of randomised controlled trials

OBJECTIVE

To evaluate the benefits and harms of low dose aspirin in people with diabetes and no cardiovascular disease.

DESIGN

Meta-analysis of randomised controlled trials.

DATA SOURCES

Medline (1966-November 2008), the Cochrane central register of controlled trials (Cochrane Library 2008;issue 4), and reference lists of retrieved articles. Review methods Randomised trials of aspirin compared with placebo or no aspirin in people with diabetes and no pre-existing cardiovascular disease were eligible for inclusion. Data on major cardiovascular events (death from cardiovascular causes, non-fatal myocardial infarction, non-fatal stroke, and all cause mortality) were extracted and pooled with a random effect model. Results are reported as relative risks with 95% confidence intervals.

RESULTS

Of 157 studies in the literature searches, six were eligible (10 117 participants). When aspirin was compared with placebo there was no statistically significant reduction in the risk of major cardiovascular events (five studies, 9584 participants; relative risk 0.90, 95% confidence interval 0.81 to 1.00), cardiovascular mortality (four studies, n=8557, 0.94; 0.72 to 1.23), or all cause mortality (four studies, n=8557; 0.93, 0.82 to 1.05). Significant heterogeneity was found in the analysis for myocardial infarction (I(2)=62.2%; P=0.02) and stroke (I(2)=52.5%; P=0.08). Aspirin significantly reduced the risk of myocardial infarction in men (0.57, 0.34 to 0.94) but not in women (1.08, 0.71 to 1.65; P for interaction=0.056). Evidence relating to harms was inconsistent.

CONCLUSIONS

A clear benefit of aspirin in the primary prevention of major cardiovascular events in people with diabetes remains unproved. Sex may be an important effect modifier. Toxicity is to be explored further.

Effects of angiotensin converting enzyme inhibitors and angiotensin II receptor antagonists on mortality and renal outcomes in diabetic nephropathy: systematic review

OBJECTIVE

To evaluate the effects of angiotensin converting enzyme (ACE) inhibitors and angiotensin II receptor antagonists (AIIRAs) on renal outcomes and all cause mortality in patients with diabetic nephropathy.

DATA SOURCES

Medline, Embase, the Cochrane controlled trials register, conference proceedings, and contact with investigators.

STUDY SELECTION

Trials comparing ACE inhibitors or AIIRAs with placebo or with each other in patients with diabetic nephropathy.

DATA EXTRACTION

Mortality, renal outcomes (end stage renal disease, doubling of serum creatinine concentration, prevention of progression of microalbuminuria to macroalbuminuria, remission of microalbuminuria), and quality of trials.

DATA SYNTHESIS

36 of 43 identified trials compared ACE inhibitors with placebo (4008 patients), four compared AIIRAs with placebo (3331 patients), and three compared ACE inhibitors with AIIRAs (206 patients). We obtained unpublished data for 11 trials. ACE inhibitors significantly reduced all cause mortality (relative risk 0.79, 95% confidence interval 0.63 to 0.99) compared with placebo but AIIRAs did not (0.99, 0.85 to 1.17), although baseline mortality was similar in the trials. Both agents had similar effects on renal outcomes. Reliable estimates of the unconfounded relative effects of ACE inhibitors compared with AIIRAs could not be obtained owing to small sample sizes.

CONCLUSION

Although the survival benefits of ACE inhibitors for patients with diabetic nephropathy are known, the relative effects of ACE inhibitors and AIIRAs on survival are unknown owing to the lack of adequate head to head trials.

The number, quality, and coverage of randomized controlled trials in nephrology

Randomized controlled trials (RCT) are the optimal study design to answer intervention questions. The authors evaluated the number, quality, and coverage of RCT in nephrology. MEDLINE was searched using the relevant medical subject headings for nephrology and 12 major specialties in internal medicine, limited by "randomized controlled trial" as a publication type. A random selection of 160 RCT in nephrology (40 for each decade) published since 1966 and an additional 270 RCT from ongoing or published Cochrane systematic reviews in various areas of nephrology, dialysis, and transplantation were evaluated for quality of reporting using standard criteria. The number of RCT published in nephrology from 1966 to 2002 (2779) is fewer than all other specialties of internal medicine (range: 5335 in hematology to 27109 in cardiology) with the proportion of all citations which are RCT being the third lowest (1.15%). There has been an increase in both indices from 1966 to 1996, but not at a greater rate than other specialties, and there has been no increase over the past 5 yr. Some areas of nephrology, in particular glomerulonephritis, are clear outliers with very low numbers of RCT to guide clinical decision-making. Overall the quality of RCT reporting in nephrology is low and has not improved over the past 30 yr with unclear allocation concealment (89%), lack of reported blinding of outcome assessors (92%), and failure to perform "intention-to-treat analysis" (50%) particularly frequent. The challenges of improving the quality and quantity of trials in nephrology are substantial, but they can be overcome by using standard guidelines and checklists for trial reporting, greater attention to the trial methods and not just the results, involving experts in trial design and reporting, multicenter collaboration, and larger and simpler trials.

Meta-analysis: erythropoiesis-stimulating agents in patients with chronic kidney disease

BACKGROUND

Previous meta-analyses suggest that treatment with erythropoiesis-stimulating agents (ESAs) in chronic kidney disease (CKD) increases the risk for death. Additional randomized trials have been recently completed.

PURPOSE

To summarize the effects of ESA treatment on clinical outcomes in patients with anemia and CKD.

DATA SOURCES

MEDLINE (January 1966 to November 2009), EMBASE (January 1980 to November 2009), and the Cochrane database (to March 2010) were searched without language restriction.

STUDY SELECTION

Two authors independently screened reports to identify randomized trials evaluating ESA treatment in people with CKD. Hemoglobin target trials or trials of ESA versus no treatment or placebo were included.

DATA EXTRACTION

Two authors independently extracted data on patient characteristics, study risks for bias, and the effects of ESA therapy.

DATA SYNTHESIS

27 trials (10 452 patients) were identified. A higher hemoglobin target was associated with increased risks for stroke (relative risk [RR], 1.51 [95% CI, 1.03 to 2.21]), hypertension (RR, 1.67 [CI, 1.31 to 2.12]), and vascular access thrombosis (RR, 1.33 [CI, 1.16 to 1.53]) compared with a lower hemoglobin target. No statistically significant differences in the risks for mortality (RR, 1.09 [CI, 0.99 to 1.20]), serious cardiovascular events (RR, 1.15 [CI, 0.98 to 1.33]), or end-stage kidney disease (RR, 1.08 [CI, 0.97 to 1.20]) were observed, although point estimates favored a lower hemoglobin target. Treatment effects were consistent across subgroups, including all stages of CKD.

LIMITATIONS

The evidence for effects on quality of life was limited by selective reporting. Trials also reported insufficient information to allow analysis of the independent effects of ESA dose on clinical outcomes.

CONCLUSION

Targeting higher hemoglobin levels in CKD increases risks for stroke, hypertension, and vascular access thrombosis and probably increases risks for death, serious cardiovascular events, and end-stage renal disease. The mechanisms for harm remain unclear, and meta-analysis of individual-patient data and trials on fixed ESA doses are recommended to elucidate these mechanisms.

PRIMARY FUNDING SOURCE

None.

Predictors of bleeding complications in percutaneous ultrasound-guided renal biopsy

BACKGROUND

The risks associated with performing a percutaneous renal biopsy have substantially decreased in the past two decades because of technical advances in the method. However, bleeding complications still occur, resulting in increased hospital stay and treatment costs.

METHODS

We investigated the predictive value of demographics (age, gender), clinical data (blood pressure), baseline chemistry (hemoglobin/hematocrit, prothrombin time, partial thromboplastin time, bleeding time, serum creatinine, daily proteinuria), and needle size for the risk of major (need for blood transfusion, nephrectomy, or angiography) or minor (no need for any intervention) postrenal biopsy bleeding complications. This was a prospective cohort study of 471 patients who underwent ultrasound-guided biopsy of native kidney by automated needle in a single center; all biopsies were performed by two experienced nephrologists. Patients with transplant kidneys were excluded from the study. Predictors of postbiopsy bleeding were assessed by multiple linear and multivariate logistic regression analysis. Data are presented as unadjusted (OR) and adjusted odds ratios (AOR) with 95% confidence intervals (CI).

RESULTS

The study cohort consisted of 471 (277 males, 194 females) patients. Of these, 161 (34.1%) experienced postbiopsy bleeding [157 (33.3%) hematomas, 2 (0.4%) gross hematuria, 2 (0.4%) arteriovenous fistula]. Major complications were seen in 6 (1.2%) patients (blood transfusion, N= 2; angiography, N= 3; nephrectomy, N= 1), but no deaths occurred. The risk of postbiopsy bleeding was higher in women (39.7% women, 30.3% men, AOR 2.05, 95% CI 1.26 to 3.31, P= 0.004), younger subjects (35.0 +/- 14.5 years vs. 40.3 + 15.4, AOR 0.80, CI 0.68 to 0.94, P= 0.006), and patients with higher baseline partial thromboplastin time (102.7 + 11.8% vs. 100.1 + 10.0%, AOR 1.26, CI 1.02 to 1.54, P= 0.032). These findings were independent of size of hematoma.

CONCLUSION

Although the methods for performing a percutaneous renal biopsy have improved in the past two decades, renal biopsy is still not a risk-free procedure. Of the data routinely collected for potential predictors of postbiopsy bleeding complications, only gender, age, and baseline partial thromboplastin time show a significant predictive value. The other variables investigated do not have any predictive value.

Effects of intensive blood pressure lowering on the progression of chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Recent guidelines suggest lowering the target blood pressure for patients with chronic kidney disease, although the strength of evidence for this suggestion has been uncertain. We sought to assess the renal and cardiovascular effects of intensive blood pressure lowering in people with chronic kidney disease.

METHODS

We performed a systematic review and meta-analysis of all relevant reports published between 1950 and July 2011 identified in a search of MEDLINE, Embase and the Cochrane Library. We included randomized trials that assigned patients with chronic kidney disease to different target blood pressure levels and reported kidney failure or cardiovascular events. Two reviewers independently identified relevant articles and extracted data.

RESULTS

We identified 11 trials providing information on 9287 patients with chronic kidney disease and 1264 kidney failure events (defined as either a composite of doubling of serum creatinine level and 50% decline in glomerular filtration rate, or end-stage kidney disease). Compared with standard regimens, a more intensive blood pressure-lowering strategy reduced the risk of the composite outcome (hazard ratio [HR] 0.82, 95% confidence interval [CI] 0.68-0.98) and end-stage kidney disease (HR 0.79, 95% CI 0.67-0.93). Subgroup analysis showed effect modification by baseline proteinuria (p = 0.006) and markers of trial quality. Intensive blood pressure lowering reduced the risk of kidney failure (HR 0.73, 95% CI 0.62-0.86), but not in patients without proteinuria at baseline (HR 1.12, 95% CI 0.67-1.87). There was no clear effect on the risk of cardiovascular events or death.

INTERPRETATION

Intensive blood pressure lowering appears to provide protection against kidney failure events in patients with chronic kidney disease, particularly among those with proteinuria. More data are required to determine the effects of such a strategy among patients without proteinuria.

Meta-analysis: vitamin D compounds in chronic kidney disease

BACKGROUND

Vitamin D compounds are widely used to prevent and treat secondary hyperparathyroidism.

PURPOSE

To determine whether vitamin D therapy improves biochemical markers of mineral metabolism and cardiovascular and mortality outcomes in chronic kidney disease.

DATA SOURCES

MEDLINE (January 1966 to July 2007), EMBASE (January 1980 to July 2007), and Cochrane databases were searched without language restriction.

STUDY SELECTION

Randomized, controlled trials of vitamin D compounds in chronic kidney disease were identified.

DATA EXTRACTION

Two authors independently extracted data.

DATA SYNTHESIS

Seventy-six trials were identified for inclusion; 3667 participants were enrolled. Vitamin D compounds did not reduce the risk for death, bone pain, vascular calcification, or parathyroidectomy. Compared with placebo, established vitamin D sterols were associated with an increased risk for hypercalcemia (relative risk, 2.37 [95% CI, 1.16 to 4.85]) and hyperphosphatemia (relative risk, 1.77 [CI, 1.15 to 2.74]) but did not show a consistent reduction in parathyroid hormone (PTH) levels. Compared with placebo, more recently developed vitamin D analogues were associated with hypercalcemia (relative risk, 5.15 [CI, 1.06 to 24.97]) but not hyperphosphatemia, and levels of PTH were reduced (weighted mean difference, -10.77 pmol/L [CI, -20.51 to -1.03 pmol/L]). For suppression of PTH, intravenous administration was superior to oral vitamin D, but higher intravenous doses were used.

LIMITATIONS

Few studies reported patient-level outcomes, including mortality (8 of 76 trials), and only 5 trials directly compared the effects of treatment with newer vitamin D compounds versus established ones. Heterogeneity in some comparisons remained unexplained by metaregression analyses.

CONCLUSION

Vitamin D compounds do not consistently reduce PTH levels, and beneficial effects on patient-level outcomes are unproven. The value of vitamin D treatment for people with chronic kidney disease remains uncertain.

Healthy Dietary Patterns and Risk of Mortality and ESRD in CKD: A Meta-Analysis of Cohort Studies

BACKGROUND AND OBJECTIVES

Patients with CKD are advised to follow dietary recommendations that restrict individual nutrients. Emerging evidence indicates overall eating patterns may better predict clinical outcomes, however, current data on dietary patterns in kidney disease are limited.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This systematic review aimed to evaluate the association between dietary patterns and mortality or ESRD among adults with CKD. Medline, Embase, and reference lists were systematically searched up to November 24, 2015 by two independent review authors. Eligible studies were longitudinal cohort studies reporting the association of dietary patterns with mortality, cardiovascular events, or ESRD.

RESULTS

A total of seven studies involving 15,285 participants were included. Healthy dietary patterns were generally higher in fruit and vegetables, fish, legumes, cereals, whole grains, and fiber, and lower in red meat, salt, and refined sugars. In six studies, healthy dietary patterns were consistently associated with lower mortality (3983 events; adjusted relative risk, 0.73; 95% confidence interval, 0.63 to 0.83; risk difference of 46 fewer (29-63 fewer) events per 1000 people over 5 years). There was no statistically significant association between healthy dietary patterns and risk of ESRD (1027 events; adjusted relative risk, 1.04; 95% confidence interval, 0.68 to 1.40).

CONCLUSIONS

Healthy dietary patterns are associated with lower mortality in people with kidney disease. Interventions to support adherence to increased fruit and vegetable, fish, legume, whole grain, and fiber intake, and reduced red meat, sodium, and refined sugar intake could be effective tools to lower mortality in people with kidney disease.

Aldosterone antagonists for preventing the progression of chronic kidney disease: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Addition of aldosterone antagonists (AA) might provide renal benefits to proteinuric chronic kidney disease (CKD) patients over and above the inhibition of renin-angiotensin system blockers (RAS). We evaluated the benefits and harms of adding selective and nonselective AA in CKD patients already on RAS.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

MEDLINE, EMBASE, and Renal Health Library were searched for relevant randomized clinical trials in adult CKD patients. Results were summarized using the random-effects model.

RESULTS

Eleven trials (991 patients) were included. In comparison to angiotensin- converting enzyme inhibitors (ACEi) and/or angiotensin receptor blockers (ARB) plus placebo, nonselective AA along with ACEi and/or ARB significantly reduced 24 h proteinuria (seven trials, 372 patients, weighted mean difference [WMD] -0.80 g, 95% CI -1.27, -0.33) and BP. This did not translate into an improvement in GFR (WMD -0.70 ml/min/1.73m(2), 95% CI -4.73, 3.34). There was a significant increase in the risk of hyperkalemia with the addition of nonselective AA to ACEi and/or ARB (relative risk 3.06, 95% CI 1.26, 7.41). In two trials, addition of selective AA to ACEi resulted in an additional reduction in 24 h proteinuria, without any impact on BP and renal function. Data on cardiovascular outcomes, long-term renal outcomes and mortality were not available in any of the trials.

CONCLUSIONS

Aldosterone antagonists reduce proteinuria in CKD patients already on ACEis and ARBs but increase the risk of hyperkalemia. Long-term effects of these agents on renal outcomes, mortality, and safety need to be established.

Cognition in People With End-Stage Kidney Disease Treated With Hemodialysis: A Systematic Review and Meta-analysis

BACKGROUND

Cognitive impairment is associated with poorer quality of life, risk for hospitalization, and mortality. Cognitive impairment is common in people with end-stage kidney disease treated with hemodialysis, yet the severity and specific cognitive deficits are uncertain.

STUDY DESIGN

Systematic review and meta-analysis.

SETTING & POPULATION

Adults receiving hemodialysis compared with the general population, people with non-dialysis-dependent chronic kidney disease (NDD-CKD), people receiving peritoneal dialysis, or people with nondialyzed chronic kidney failure.

SELECTION CRITERIA FOR STUDIES

Randomized controlled trials, cohort or cross-sectional studies without language restriction.

INDEX TESTS

Validated neuropsychological tests of cognition.

OUTCOMES

Cognitive test scores, aggregated by cognitive domain: orientation and attention, perception, memory, language, construction and motor performance, concept formation and reasoning, and executive functions.

RESULTS

42 studies of 3,522 participants. Studies were of high or uncertain risk of bias, assessed by the Newcastle-Ottawa Scale. People treated with hemodialysis had worse cognition than the general population, particularly in attention (n=22; standardized mean difference [SMD], -0.93; 95% CI, -1.18 to -0.68). Hemodialysis patients performed better than nondialyzed patients with chronic kidney failure in attention (n=6; SMD, 0.70; 95% CI, 0.45 to 0.96) and memory (n=6; SMD, 0.36; 95% CI, 0.08 to 0.63), but had poorer memory than the general population (n=16; SMD, -0.41; 95% CI, -0.91 to 0.09) and people with NDD-CKD (n=5; SMD, -0.40; 95% CI, -0.60 to -0.21). There were insufficient data to show other differences among people receiving hemodialysis and those receiving peritoneal dialysis or with NDD-CKD.

LIMITATIONS

Potentially biased studies, not wholly adjusted for education. High heterogeneity, mainly due to the large variety of tests used to assess cognition.

CONCLUSIONS

People treated with hemodialysis have impaired cognitive function compared to the general population, particularly in the domains of orientation and attention and executive function. Cognitive deficits in specific domains should be further explored in this population and should be considered when approaching education and chronic disease management.

Effects of antiplatelet therapy on mortality and cardiovascular and bleeding outcomes in persons with chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Antiplatelet agents are used to prevent cardiovascular events; however, treatment effects may differ in persons with chronic kidney disease (CKD) because atherosclerotic disease is less prevalent, whereas bleeding hazards may be increased in this population.

PURPOSE

To summarize the effects of antiplatelet treatment on cardiovascular events, mortality, and bleeding in persons with CKD.

DATA SOURCES

Embase and Cochrane databases through November 2011 without language restriction.

STUDY SELECTION

Randomized trials that included adults with CKD and compared antiplatelet agents with standard care, placebo, or no treatment.

DATA EXTRACTION

Data for populations, interventions, outcomes, and risk for bias were extracted. Quality of evidence for treatment effects on myocardial infarction, death, and bleeding was summarized by using Grading of Recommendations Assessment, Development, and Evaluation guidelines.

DATA SYNTHESIS

Nine trials (all post hoc subgroup analyses for CKD) involving 9969 persons who had acute coronary syndromes or were undergoing percutaneous coronary intervention and 31 trials involving 11,701 persons with stable or no cardiovascular disease were identified. Low-quality evidence has found that in persons with acute coronary syndromes, glycoprotein IIb/IIIa inhibitors or clopidogrel plus standard care compared with standard care alone had little or no effect on all-cause or cardiovascular mortality or on myocardial infarction but increased serious bleeding. Compared with placebo or no treatment in persons with stable or no cardiovascular disease, antiplatelet agents prevented myocardial infarction but had uncertain effects on mortality and increased minor bleeding according to generally low-quality evidence.

LIMITATIONS

Data for antiplatelet agents in persons with CKD are frequently derived from post hoc analyses of trials of broader populations. Definitions for bleeding outcomes and trial duration were heterogeneous.

CONCLUSION

Benefits for antiplatelet therapy among persons with CKD are uncertain and are potentially outweighed by bleeding hazards.

PRIMARY FUNDING SOURCE

None.

Treatment of diffuse proliferative lupus nephritis: a meta-analysis of randomized controlled trials

BACKGROUND

In this systematic review of randomized controlled trials (RCTs), we assess the benefits and harm of current treatments for diffuse proliferative lupus nephritis (DPLN).

METHODS

The Cochrane Controlled Trial Registry, MEDLINE, and EMBASE were searched for RCTs of treatment for DPLN. All available RCTs of patients with biopsy-proven DPLN were included, and data were extracted for overall mortality, end-stage renal disease, doubling of serum creatinine level, relapse, major infection, herpes zoster infection, ovarian failure, malignancy, and bladder toxicity. Treatment effects on these outcomes were summarized as relative risk (RR) with 95% confidence interval (CI) and pooled by using a random-effects model.

RESULTS

Twenty-five of 920 articles identified were eligible RCTs and were included. The majority compared cyclophosphamide or azathioprine plus steroids versus steroids alone. Cyclophosphamide plus steroids reduced the risk for doubling of serum creatinine level (4 RCTs, 228 patients; RR, 0.59; 95% CI, 0.40 to 0.88) compared with steroids alone, but had no impact on overall mortality (5 RCTs, 226 patients; RR, 0.98; 95% CI, 0.53 to 1.82). However, risk for ovarian failure was increased significantly (3 RCTs, 147 patients; RR, 2.18; 95% CI, 1.10 to 4.34). In studies from the 1970s, azathioprine plus steroids reduced the risk for all-cause mortality compared with steroids alone (3 RCTs, 78 patients; RR, 0.60; 95% CI, 0.36 to 0.99), but had no effect on renal outcomes. Neither therapy was associated with increased risk for major infection. The addition of plasma exchange to these treatments offered no benefit, and information on other agents, including mycophenolate mofetil, was insufficient for analysis.

CONCLUSION

Until future RCTs of newer agents are completed, the current use of cyclophosphamide combined with steroids remains the best option to preserve renal function in patients with DPLN. The smallest effective dose and shortest duration of treatment should be used to minimize gonadal toxicity without compromising efficacy.

Benefits and harms of phosphate binders in CKD: a systematic review of randomized controlled trials

BACKGROUND

Phosphate binders are widely used to control serum phosphorus levels in patients with chronic kidney disease (CKD). We analyzed the effects of phosphate binders on biochemical and patient-level end points in patients with CKD.

STUDY DESIGN

Systematic review and meta-analysis by searching MEDLINE (1966 to April 2009), EMBASE (1980 to April 2009), and the Cochrane Renal Group Specialised Register and the Cochrane Central Register of Controlled Trials (CENTRAL).

SETTING & POPULATION

Patients with CKD.

SELECTION CRITERIA FOR STUDIES

Randomized controlled trials.

INTERVENTION

Phosphate binders.

OUTCOMES

Serum phosphorus, calcium, and parathyroid hormone levels; incidence of hypercalcemia; all-cause mortality; adverse effects.

RESULTS

40 trials (6,406 patients) were included. There was no significant decrease in all-cause mortality (10 randomized controlled trials; 3,079 patients; relative risk [RR], 0.73; 95% confidence interval [CI], 0.46 to 1.16), hospitalization, or end-of-treatment serum calcium-phosphorus product levels with sevelamer compared with calcium-based agents. There was a significant decrease in end-of-treatment phosphorus and parathyroid hormone levels with calcium salts compared with sevelamer and a significant decrease in risk of hypercalcemia (RR, 0.47; 95% CI, 0.36 to 0.62) with sevelamer compared with calcium-based agents. There was a significant increase in risk of gastrointestinal adverse events with sevelamer in comparison to calcium salts (RR, 1.39; 95% CI, 1.04 to 1.87). Compared with calcium-based agents, lanthanum significantly decreased end-of-treatment serum calcium and calcium-phosphorus product levels, but with similar end-of-treatment phosphorus levels. Effects of calcium acetate on biochemical end points were similar to those of calcium carbonate. Existing data are insufficient to conclude for a differential impact of any phosphate binder on cardiovascular mortality or other patient-level outcome.

LIMITATIONS

Few long-term studies of the efficacy of phosphate binders on mortality and musculoskeletal morbidity, significant heterogeneity for many surrogate outcomes, and suboptimal reporting of study methods to determine trial quality.

CONCLUSION

Currently, there are insufficient data to establish the comparative superiority of non-calcium-binding agents over calcium-containing phosphate binders for such important patient-level outcomes as all-cause mortality and cardiovascular end points. Additional trials are still required to examine the differential effects of phosphate-binding agents on these end points and the mineral homeostasis pathway.

Catheter-related interventions to prevent peritonitis in peritoneal dialysis: a systematic review of randomized, controlled trials

As many as 15 to 50% of end-stage kidney disease patients are on peritoneal dialysis (PD), but peritonitis limits its more widespread use. Several PD catheter-related interventions (catheter designs, surgical insertion approaches, and connection methods) have been purported to reduce the risk of peritonitis in PD. The goal was to assess the trial evidence supporting their use. The Cochrane CENTRAL Registry, MEDLINE, EMBASE, and reference lists were searched for randomized trials of catheter types and related interventions in PD. Two reviewers extracted data on the rates of peritonitis and exit-site/tunnel infection, catheter removal/replacement, technique failure, and all-cause mortality. Analysis was by a random effects model, and results are expressed as relative risk and 95% confidence intervals. Thirty-seven eligible trials (2822 patients) were identified: eight of surgical strategies of catheter insertion, eight of straight versus coiled catheters, 10 of Y-set versus conventional spike systems, four of Y-set versus double-bag systems, and seven of other interventions. Despite the large total number of patients, few trials covered the same interventions, small numbers of patients were enrolled in each trial, and the methodologic quality was suboptimal. Y-set and twin-bag systems were superior to conventional spike systems (seven trials, 485 patients; relative risk, 0.64; 95% confidence intervals 0.53 to 0.77), and no other catheter-related intervention was demonstrated to prevent peritonitis in PD. This systematic review demonstrates that of all catheter-related interventions designed to prevent peritonitis in PD, only disconnect (twin-bag and Y-set) systems have been proved to be effective (compared with conventional spike systems). Despite the importance of PD as a renal replacement therapy modality and the large number of patients who receive it, it is still not known whether any particular PD catheter designs, implantation techniques, or modalities are effective, given the limitations of available trials.

Healthy Dietary Patterns and Incidence of CKD: A Meta-Analysis of Cohort Studies

BACKGROUND AND OBJECTIVES

Whether a healthy dietary pattern may prevent the incidence of developing CKD is unknown. This study evaluated the associations between dietary patterns and the incidence of CKD in adults and children.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This systematic review and meta-analysis identified potential studies through a systematic search of MEDLINE, Embase and references from eligible studies from database inception to February 2019. Eligible studies were prospective and retrospective cohort studies including adults and children without CKD, where the primary exposure was dietary patterns. To be eligible, studies had to report on the primary outcome, incidence of CKD (eGFR<60 ml/min per 1.73 m²). Two authors independently extracted data, assessed risk of bias and evidence certainty using the Newcastle-Ottawa scale and GRADE.

RESULTS

Eighteen prospective cohort studies involving 630,108 adults (no children) with a mean follow-up of 10.4±7.4 years were eligible for analysis. Included studies had an overall low risk of bias. The evidence certainty was moderate for CKD incidence and low for eGFR decline (percentage drop from baseline or reduced by at least 3 ml/min per 1.73 m² per year) and incident albuminuria. Healthy dietary patterns typically encouraged higher intakes of vegetables, fruit, legumes, nuts, whole grains, fish and low-fat dairy, and lower intakes of red and processed meats, sodium, and sugar-sweetened beverages. A healthy dietary pattern was associated with a lower incidence of CKD (odds ratio [OR] 0.70 (95% confidence interval [95% CI], 0.60 to 0.82); I²=51%; eight studies), and incidence of albuminuria (OR 0.77, [95% CI, 0.59 to 0.99]; I²=37%); four studies). There appeared to be no significant association between healthy dietary patterns and eGFR decline (OR 0.70 [95% CI, 0.49 to 1.01], I²=49%; four studies).

CONCLUSIONS

A healthy dietary pattern may prevent CKD and albuminuria.

A novel simpler histological classification for renal survival in IgA nephropathy: a retrospective study

BACKGROUND

Patients with immunoglobulin A (IgA) nephropathy may progress to end-stage renal disease (ESRD) within 10 to 20 years after renal biopsy. We evaluated factors associated with long-term renal survival by using a novel simplified histological classification.

STUDY DESIGN

Retrospective study.

SETTING & PARTICIPANTS

437 patients (296 men, 141 women) with IgA nephropathy seen at our single center from January 1971 to December 2006. Most patients received treatment with renin-angiotensin system inhibitors.

PREDICTORS

Baseline age, sex, presence of hematuria, presence of hypertension, serum creatinine level, urine protein at baseline, and 2 histological classifications.

OUTCOMES & MEASUREMENTS

Relationship of baseline factors to time to ESRD was evaluated by means of univariate and multivariate analysis with log-rank test and the Cox proportional hazard method.

RESULTS

In a mean follow-up of 107.6 months, 72 ESRD events occurred. The 5-, 10-, 15-, and 20-year renal survival rates after renal biopsy were 94.1%, 82.1%, 73.1%, and 60.3%, respectively. Independent baseline predictors of increased ESRD risk were microhematuria with absence of recurrent macrohematuria (adjusted hazard ratio [HR], 2.18; 95% confidence interval [CI], 1.30 to 3.65; P = 0.003), 1.0 mg/dL (88.4 mumol/L) higher serum creatinine level (HR, 1.50; 95% CI, 1.10 to 2.07; P = 0.013), proteinuria with 1.0 g/dL (10.0 g/L) greater protein (HR, 1.28; 95% CI, 1.07 to 1.52; P = 0.006), and grading of histological lesions. A 1-grade increase according to our 3-grade classification was associated with a nearly 6-fold ESRD risk increase (adjusted HR, 5.95; 95% CI, 3.54 to 10.01; P < 0.0001).

LIMITATIONS

Lack of adjustment for changes in treatment that may have occurred during the study period.

CONCLUSIONS

Renal damage progression in patients with IgA nephropathy was associated with microscopic hematuria at clinical onset, increased serum creatinine level, increased proteinuria, and grading of histological lesions. Our classification system appears simpler than other classifications and is associated with ESRD risk, which could help identify individual high-risk patients and stratify patients enrolled in randomized clinical trials into homogeneous groups.

Prevalence and correlates of self-reported sexual dysfunction in CKD: a meta-analysis of observational studies

BACKGROUND

Sexual dysfunction is an under-recognized problem in men and women with chronic kidney disease (CKD). The prevalence, correlates, and predictors of this condition in patients with CKD have not been evaluated comprehensively.

STUDY DESIGN

Systematic review and meta-analysis.

SETTING & POPULATION

Patients treated using dialysis (dialysis patients), patients treated using transplant (transplant recipients), and patients with CKD not treated using dialysis or transplant (nondialysis nontransplant patients with CKD).

SELECTION CRITERIA FOR STUDIES

Observational studies conducted in patients with CKD only or including a control group without CKD.

PREDICTOR

Type of study population.

OUTCOMES

Sexual dysfunction in men and women with CKD using validated tools, such as the International Index of Erectile Function, the Female Sexual Function Index (FSFI), or other measures as reported by study investigators.

RESULTS

50 studies (8,343 patients) of variable size (range, 16-1,023 patients) were included in this review. Almost all studies explored sexual dysfunction in men and specifically erectile dysfunction. The summary estimate of erectile dysfunction in men with CKD was 70% (95% CI, 62%-77%; 21 studies, 4,389 patients). Differences in reported prevalence rates of erectile dysfunction between different studies were attributable primarily to age, study populations, and type of study tool used to assess the presence of erectile dysfunction. In women, the reported prevalence of sexual dysfunction was assessed in only 306 patients from 2 studies and ranged from 30%-80%. Compared with the general population, women with CKD had a significantly lower overall FSFI score (8 studies or subgroups, 407 patients; mean difference, -9.28; 95% CI, -12.92 to -5.64). Increasing age, diabetes mellitus, and depression consistently were found to correlate with sexual dysfunction in 20 individual studies of patients with CKD using different methods.

LIMITATIONS

Suboptimal and lack of uniform assessment of outcome measures.

CONCLUSIONS

Sexual dysfunction is highly prevalent in both men and women with CKD, especially among those on dialysis. Larger studies enrolling different ethnic groups, using validated study tools, and analyzing the influence of various factors on the development of sexual dysfunction are needed.