Giusi Graziano

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 (I2=62.2%; P=0.02) and stroke (I2=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.

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.

Geographical variations in sex ratio trends over time in multiple sclerosis

Background A female/male (F/M) ratio increase over time in multiple sclerosis (MS) patients was demonstrated in many countries around the world. So far, a direct comparison of sex ratio time-trends among MS populations from different geographical areas was not carried out. Objective In this paper we assessed and compared sex ratio trends, over a 60-year span, in MS populations belonging to different latitudinal areas. Methods Data of a cohort of 15,996 (F = 11,290; M = 4,706) definite MS with birth years ranging from 1930 to 1989 were extracted from the international MSBase registry and the New Zealand MS database. Gender ratios were calculated by six decades based on year of birth and were adjusted for the F/M born-alive ratio derived from the respective national registries of births. Results Adjusted sex ratios showed a significant increase from the first to the last decade in the whole MS sample (from 2.35 to 2.73; p = 0.03) and in the subgroups belonging to the areas between 83° N and 45° N (from 1.93 to 4.55; p<0.0001) and between 45° N to 35° N (from 1.46 to 2.30; p<0.05) latitude, while a sex ratio stability over time was found in the subgroup from areas between 12° S and 55° S latitude. The sex ratio increase mainly affected relapsing-remitting (RR) MS. Conclusions Our results confirm a general sex ratio increase over time in RRMS and also demonstrate a latitudinal gradient of this increase. These findings add useful information for planning case-control studies aimed to explore sex-related factors responsible for MS development.

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.

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.

Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers and combined therapy in patients with micro- and macroalbuminuria and other cardiovascular risk factors: a systematic review of randomized controlled trials

BACKGROUND A recent clinical trial showed harmful renal effects with the combined use of angiotensin-converting enzyme inhibitors (ACEI) and angiotensin-II receptor blockers (ARB) in people with diabetes or vascular disease. We examined the benefits and risks of these agents in people with albuminuria and one or more cardiovascular risk factors. METHODS MEDLINE, EMBASE and Renal Health Library were searched for trials comparing ACEI, ARB or their combination with placebo or with one another in people with albuminuria and one or more cardiovascular risk factor. RESULTS Eighty-five trials (21,708 patients) were included. There was no significant reduction in the risk of all-cause mortality or fatal cardiac-cerebrovascular outcomes with ACEI versus placebo, ARB versus placebo, ACEI versus ARB or with combined therapy with ACEI + ARB versus monotherapy. There was a significant reduction in the risk of nonfatal cardiovascular events with ACEI versus placebo but not with ARB versus placebo, ACEI versus ARB or with combined therapy with ACEI + ARB versus monotherapy. Development of end-stage kidney disease and progression of microalbuminuria to macroalbuminuria were reduced significantly with ACEI versus placebo and ARB versus placebo but not with combined therapy with ACEI + ARB versus monotherapy. CONCLUSIONS ACEI and ARB exert independent renal and nonfatal cardiovascular benefits while their effects on mortality and fatal cardiovascular disease are uncertain. There is a lack of evidence to support the use of combination therapy. A comparative clinical trial with ACE, ARB and its combination in people with albuminuria and a cardiovascular risk factor is warranted.

Antiplatelet Therapy to Prevent Hemodialysis Vascular Access Failure: Systematic Review and Meta-analysis

BACKGROUND Hemodialysis vascular access failure occurs often and increases morbidity for people on hemodialysis therapy. Antiplatelet agents may prevent hemodialysis vascular access failure, but potentially may be hazardous in people with end-stage kidney disease who have impaired hemostasis. STUDY DESIGN Systematic review and meta-analysis of randomized controlled trials. SETTING & POPULATION Adults on long-term hemodialysis therapy. SELECTION CRITERIA Trials evaluating hemodialysis vascular access outcomes identified by searches in Cochrane CENTRAL and Renal Group Trial Registers and Embase, without language restriction. INTERVENTION Antiplatelet therapy. OUTCOMES Hemodialysis vascular access failure (thrombosis or loss of patency), failure to attain vascular access suitable for dialysis, need for intervention to attain patency or assist maturation, major bleeding, minor bleeding, and antiplatelet treatment withdrawal. Treatment effects were summarized as RRs with 95% CIs using random-effects meta-analysis. RESULTS 21 eligible trials (4,826 participants) comparing antiplatelet treatment with placebo or no treatment were included. 12 trials (3,118 participants) started antiplatelet therapy around the time of dialysis vascular access surgery and continued treatment for approximately 6 months. Antiplatelet treatment reduced fistula failure (thrombosis or loss of patency) by one-half (6 trials, 1,222 participants; RR, 0.49; 95% CI, 0.30-0.81) but had uncertain effects on graft patency and attaining fistula or graft function suitable for dialysis. Overall, antiplatelet treatment had uncertain effects on major bleeding. LIMITATIONS Unclear or high risk of bias in most trials and few trial data, particularly for antiplatelet effects on graft function and vascular access suitability for dialysis. CONCLUSIONS Antiplatelet treatment protects fistula from thrombosis or loss of patency, but has little or no effect on graft patency and uncertain effects on vascular access maturation for dialysis and major bleeding. Interventions that demonstrably improve vascular access suitability for dialysis are needed.

The burden of hospitalization related to diabetes mellitus: A population-based study

BACKGROUND AND AIMS To estimate the impact of diabetes and its complications, overall and in different age classes, on the likelihood of hospital admission for specific causes. METHODS AND RESULTS We carried out a record-linkage analysis of administrative registers including data on 8,940,420 citizens in 21 Local Health Authorities in Italy. Individuals with pharmacologically treated diabetes (≥2 prescriptions of antidiabetic agents during the year 2008) were paired in a 1:1 proportion with those who did not receive such drugs (controls) based on propensity-score matching. Odds Ratios (ORs) of hospitalization for macro and microvascular conditions in individuals with diabetes as compared to controls were estimated. The system identified 498,825 individuals with diabetes pharmacologically treated (prevalence of 5.6%). Prevalence of diabetes in people aged <14 years, 14-39 years, 40-65 years, and ≥65 years was 0.1%, 0.6%, 6.4%, and 18.2%, respectively. Overall, 23.9% of subjects with diabetes and 11.5% of controls had had at least a hospital admission during 12 months for the causes considered. Diabetes increased the likelihood of hospitalization by two to six times for the different causes examined. In absolute terms, diabetes was responsible for an excess of over 12,000 hospital admissions per 100,000 individuals/year. CONCLUSION Despite the availability of effective treatments to prevent or delay major complications, diabetes still places an enormous burden on both patients and the health care system. Given the continuous rise in diabetes prevalence both in middle-aged and elderly individuals, we can expect an additional, hardly sustainable increase in the demand for health care in the near future.

Treatment Options for Sexual Dysfunction in Patients with Chronic Kidney Disease: A Systematic Review of Randomized Controlled Trials

BACKGROUND AND OBJECTIVES Sexual dysfunction is very common in patients with chronic kidney disease (CKD), but treatment options are limited. The benefits and harms of existing interventions for treatment of sexual dysfunction were assessed in patients with CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS MEDLINE (1966 to December 2008), EMBASE (1980 to December 2008), and the Cochrane Trial Registry (Issue 4 2008) were searched for parallel and crossover randomized and quasi-randomized trials. Treatment effects were summarized as mean differences (MD) or standardized mean difference (SMD) with 95% confidence intervals (CI) using a random effects model. RESULTS Fourteen trials (328 patients) were included. Phosphodiesterase-5 inhibitors (PDE5i) compared with placebo significantly increased the overall International Index of Erectile Function-5 (IIEF-5) score (three trials, 101 patients, MD 1.81, 95% CI 1.51 to 2.10), all of its individual domains, and the complete 15-item IIEF-5 (two trials, 80 patients, MD 10.64, 95% CI 5.32 to 15.96). End-of-treatment testosterone levels were not significantly increased by addition of zinc to dialysate (two trials, 22 patients, SMD 0.19 ng/dl, 95% CI -2.12 to 2.50), but oral zinc improved end-of-treatment testosterone levels. There was no difference in plasma luteinizing and follicle-stimulating hormone level at the end of the study period with zinc therapy. CONCLUSIONS PDE5i and zinc are promising interventions for treating sexual dysfunction in CKD. Evidence supporting their routine use in CKD patients is limited. There is an unmet need for studying interventions for male and female sexual dysfunction in CKD considering the significant disease burden.

Joint spatial analysis of gastrointestinal infectious diseases.

A major obstacle in the spatial analysis of infectious disease surveillance data is the problem of under-reporting. This article investigates the possibility of inferring reporting rates through joint statistical modelling of several infectious diseases with different aetiologies. Once variation in under-reporting can be estimated, geographic risk patterns for infections associated with specific food vehicles may be discerned. We adopt the shared component model, proposed by Knorr-Held and Best for two chronic diseases and further extended by (Held L, Natario I, Fenton S, Rue H, Becker N. Towards joint disease mapping. Statistical Methods in Medical Research 2005b; 14: 61-82) for more than two chronic diseases to the infectious disease setting. Our goal is to estimate a shared component, common to all diseases, which may be interpreted as representing the spatial variation in reporting rates. Additional components are introduced to describe the real spatial variation of the different diseases. Of course, this interpretation is only allowed under specific assumptions, in particular, the geographical variation in under-reporting should be similar for the diseases considered. In addition, it is vital that the data do not contain large local outbreaks, so adjustment based on a time series method recently proposed by (Held L, Höhle M, Hofmann M. A statistical framework for the analysis of multivariate infectious disease surveillance data. Statistical Modelling 2005a; 5: 187-99) is made at a preliminary stage. We will illustrate our approach through the analysis of gastrointestinal diseases notification data obtained from the German infectious disease surveillance system, administered by the Robert Koch Institute in Berlin.