EFFECTS OF THE MEDITERRANEAN DIET ON CARDIOVASCULAR OUTCOMES: A SYSTEMATIC REVIEW AND META-ANALYSIS

BACKGROUND: A Mediterranean dietary pattern is widely recommended for the prevention of chronic disease. We sought to define the most likely effects of the Mediterranean diet on vascular disease and mortality. METHODS: We searched MEDLINE, EMBASE and the Cochrane Central Register without language restriction for randomized controlled trials comparing Mediterranean to control diets. Data on study design, patient characteristics, interventions, follow-up duration, outcomes and adverse events were sought. Individual study relative risks (RR) were pooled to create summary estimates. RESULTS: Six studies with a total of 10950 participants were included. Effects on major vascular events (n = 477), death (n = 693) and vascular deaths (n = 315) were reported for 3, 5 and 4 studies respectively. For one large study (n = 1000) there were serious concerns about the integrity of the data. When data for all studies were combined there was evidence of protection against major vascular events (RR 0.63, 95% confidence interval 0.53-0.75), coronary events (0.65, 0.50-0.85), stroke (0.65, 0.48-0.88) and heart failure (0.30, 0.17-0.56) but not for all-cause mortality (1.00, 0.86-1.15) or cardiovascular mortality (0.90, 0.72-1.11). After the study of concern was excluded the benefit for vascular events (0.69, 0.55-0.86) and stroke (0.66, 0.48-0.92) persisted but apparently positive findings for coronary events (0.73, 0.51-1.05) and heart failure (0.25, 0.05-1.17) disappeared. CONCLUSION: The Mediterranean diet may protect against vascular disease. However, both the quantity and quality of the available evidence is limited and highly variable. Results must be interpreted with caution

Diabetes and hypertension markedly increased the risk of ischemic stroke associated with high serum resistin concentration in a general Japanese population: the Hisayama Study

<p>Abstract</p> <p>Background</p> <p>Resistin, secreted from adipocytes, causes insulin resistance in mice. The relationship between resistin and coronary artery disease is highly controversial, and the information regarding resistin and ischemic stroke is limited. In the present study, the association between serum resistin concentration and cardiovascular disease (CVD) was investigated in a general Japanese population.</p> <p>Methods</p> <p>A total of 3,201 community-dwelling individuals aged 40 years or older (1,382 men and 1,819 women) were divided into quintiles of serum resistin, and the association between resistin and CVD was examined cross-sectionally. The combined effect of either diabetes or hypertension and high serum resistin was also assessed. Serum resistin was measured using ELISA.</p> <p>Results</p> <p>Compared to those without CVD, age- and sex-adjusted mean serum resistin concentrations were greater in subjects with CVD (p = 0.002) or ischemic stroke (p < 0.001), especially in those with lacunar and atherothrombotic infarction, but not elevated in subjects with hemorrhagic stroke or coronary heart disease. When analyzed by quintile of serum resistin concentration, the age- and sex-adjusted odds ratio (OR) for having CVD and ischemic stroke increased with quintile of serum resistin (p for trends, 0.02 for CVD, < 0.001 for ischemic stroke), while such associations were not observed for hemorrhagic stroke or coronary heart disease. Compared to the first quintile, the age- and sex-adjusted OR of ischemic stroke was greater in the third (OR = 3.54; 95% confidence interval [CI], 1.17-10.67; p = 0.02), fourth (OR = 4.48; 95% CI, 1.53-13.09; p = 0.006), and fifth quintiles (OR = 4.70; 95% CI, 1.62-13.61; p = 0.004). These associations remained substantially unchanged even after adjustment for other confounding factors including high-sensitivity C-reactive protein. In the stratified analysis, the combination of high serum resistin and either diabetes or hypertension markedly increased the risk of ischemic stroke.</p> <p>Conclusion</p> <p>Elevated serum resistin concentration appears to be an independent risk factor for ischemic stroke, especially lacunar and atherothrombotic infarction in the general Japanese population. The combination of high resistin and the presence of either diabetes or hypertension increased the risk of ischemic stroke.</p

Impact of Visit-to-Visit Glycemic Variability on the Risks of Macrovascular and Microvascular Events and All-Cause Mortality in Type 2 Diabetes: The ADVANCE Trial

OBJECTIVE There is no consensus on the importance of visit-to-visit glycemic variability in diabetes. Therefore, we assessed the effects of visit-to-visit variability (VVV) in HbA1c and fasting glucose on major outcomes in the ADVANCE (Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation) trial. RESEARCH DESIGN AND METHODS ADVANCE was a factorial randomized controlled trial of intensive glucose control and blood pressure lowering in patients with type 2 diabetes. VVV in the intensive glucose treatment group was defined using the SD of five measurements of HbA1c and glucose taken 3–24 months after randomization. Outcomes were combined macro- and microvascular events and all-cause mortality occurring post 24 months. Sensitivity analyses were performed using other indices of variability and in the standard glucose treatment group. RESULTS Among 4,399 patients in the intensive group, an increase in VVV of HbA1c was associated with an increased risk of vascular events (P = 0.01) and with mortality (P &lt; 0.001): highest versus lowest tenth hazard ratio (95% CI) 1.64 (1.05–2.55) and 3.31 (1.57–6.98), respectively, after multivariable adjustment. A clear association was also observed between VVV of fasting glucose and increased risk of vascular events (P &lt; 0.001; 2.70 [1.65–4.42]). HbA1c variability was positively associated with the risk of macrovascular events (P = 0.02 for trend), whereas glucose variability was associated with both macro- and microvascular events (P = 0.005 and P &lt; 0.001 for trend, respectively). Sensitivity analyses using other indices, and patients in the standard glucose treatment group, were broadly consistent with these results. CONCLUSIONS Consistency of glycemic control is important to reduce the risks of vascular events and death in type 2 diabetes

The effect of folic acid based homocysteine lowering on cardiovascular events in people with kidney disease: systematic review and meta-analysis

Objective To systematically review the effect of folic acid based homocysteine lowering on cardiovascular outcomes in people with kidney disease

The Impacts of Albuminuria and Low eGFR on the Risk of Cardiovascular Death, All-Cause Mortality, and Renal Events in Diabetic Patients: Meta-Analysis

Background:Precise effects of albuminuria and low estimated glomerular filtration rate (eGFR) on cardiovascular mortality, all-cause mortality, and renal events in diabetic patients are uncertain.Materials and Methods:A systematic review was conducted of the literature through MEDLINE, EMBASE, and CINHAL from 1950 to December 2010. Cohort studies of diabetic patients providing adjusted relative risk (RR) of albuminuria and eGFR for risks of cardiovascular mortality, all-cause mortality, and renal events were selected. Two reviewers screened abstracts and full papers of each study using standardized protocol.Results:We identified 31 studies fulfilling the criteria from 6546 abstracts. With regard to the risk of cardiovascular mortality, microalbuminuria (RR 1.76, 95%CI 1.38-2.25) and macroalbuminuria (RR 2.96 95%CI 2.44-3.60) were significant risk factors compared to normoalbuminuria. The same trends were seen in microalbuminuria (RR 1.60, 95%CI 1.42-1.81), and macroalbuminuria (RR 2.64, 95%CI 2.13-3.27) for the risk of all-cause mortality, and also in microalbuminuria (RR 3.21, 95%CI 2.05-5.02) and macroalbuminuria (RR 11.63, 95%CI 5.68-23.83) for the risk of renal events. The magnitudes of relative risks associated with low eGFR along with albuminuria were almost equal to multiplying each risk rate of low eGFR and albuminuria. No significant factors were found by investigating potential sources of heterogeneity using subgroup analysis.Conclusions:High albuminuria and low eGFR are relevant risk factors in diabetic patients. Albuminuria and low eGFR may be independent of each other. To evaluate the effects of low eGFR, intervention, or race, appropriately designed studies are needed. © 2013 Toyama et al

Antioxidants for chronic kidney disease

Background Chronic kidney disease (CKD) is a significant risk factor for premature cardiovascular disease and death. Increased oxidative stress in people with CKD has been implicated as a potential causative factor for some cardiovascular diseases. Antioxidant therapy may reduce cardiovascular mortality and morbidity in people with CKD. Objectives To examine the benefits and harms of antioxidant therapy on mortality and cardiovascular events in people with CKD stages 3 to 5; dialysis, and kidney transplantation patients. Search methods We searched the Cochrane Renal Group's specialised register (July 2011), CENTRAL (Issue 6, 2011), MEDLINE (from 1966) and EMBASE (from 1980). Selection criteria We included all randomised controlled trials (RCTs) investigating the use of antioxidants for people with CKD, or subsets of RCTs reporting outcomes for participants with CKD. Data collection and analysis Titles and abstracts were screened independently by two authors who also performed data extraction using standardised forms. Results were pooled using the random effects model and expressed as either risk ratios (RR) or mean difference (MD) with 95% confidence intervals (CI). Main results We identified 10 studies (1979 participants) that assessed antioxidant therapy in haemodialysis patients (two studies); kidney transplant recipients (four studies); dialysis and non‐dialysis CKD patients (one study); and patients requiring surgery (one study). Two additional studies reported the effect of an oral antioxidant inflammation modulator in patients with CKD (estimated glomerular filtration rate (eGFR) 20 to 45 mL/min/1.73 m²), and post‐hoc findings from a subgroup of people with mild‐to‐moderate renal insufficiency (serum creatinine ≥125 μmol/L) respectively. Interventions included different doses of vitamin E (two studies); multiple antioxidant therapy (three studies); co‐enzyme Q (one study); acetylcysteine (one study); bardoxolone methyl (one study); and human recombinant superoxide dismutase (two studies). Compared with placebo, antioxidant therapy showed no clear overall effect on cardiovascular mortality (RR 0.95, 95% CI 0.70 to 1.27; P = 0.71); all‐cause mortality (RR 0.93, 95% CI 0.76 to 1.14; P = 0.48); cardiovascular disease (RR 0.78, 95% CI 0.52 to 1.18; P = 0.24); coronary heart disease (RR 0.71, 95% CI 0.42 to 1.23; P = 0.22); cerebrovascular disease (RR 0.91, 95% CI 0.63 to 1.32; P = 0.63); or peripheral vascular disease (RR 0.54, 95% CI 0.26 to 1.12; P = 0.10). Subgroup analyses found no evidence of significant heterogeneity based on proportions of males (P = 0.99) or diabetes (P = 0.87) for cardiovascular disease. There was significant heterogeneity for cardiovascular disease when studies were analysed by CKD stage (P = 0.003). Significant benefit was conferred by antioxidant therapy for cardiovascular disease prevention in dialysis patients (RR 0.57, 95% CI 0.41 to 0.80; P = 0.001), although no effect was observed in CKD patients (RR 1.06, 95% CI 0.84 to 1.32; P = 0.63). Antioxidant therapy was found to significantly reduce development of end‐stage of kidney disease (ESKD) (RR 0.50, 95% CI 0.25 to 1.00; P = 0.05); lowered serum creatinine levels (MD 1.10 mg/dL, 95% CI 0.39 to 1.81; P = 0.003); and improved creatinine clearance (MD 14.53 mL/min, 95% CI 1.20 to 27.86; P = 0.03). Serious adverse events were not significantly increased by antioxidants (RR 2.26, 95% CI 0.74 to 6.95; P = 0.15). Risk of bias was assessed for all studies. Studies that were classified as unclear for random sequence generation or allocation concealment reported significant benefits from antioxidant therapy (RR 0.57, 95% CI 0.41 to 0.80; P = 0.001) compared with studies at low risk of bias (RR 1.06, 95% CI 0.84 to 1.32; P = 0.63). Authors' conclusions Although antioxidant therapy does not reduce the risk of cardiovascular and all‐cause death or major cardiovascular events in people with CKD, it is possible that some benefit may be present, particularly in those on dialysis. However, the small size and generally suboptimal quality of the included studies highlighted the need for sufficiently powered studies to confirm this possibility. Current evidence suggests that antioxidant therapy in predialysis CKD patients may prevent progression to ESKD; this finding was however based on a very small number of events. Further studies with longer follow‐up are needed for confirmation. Appropriately powered studies are needed to reliably assess the effects of antioxidant therapy in people with CKD

The consistency of the treatment effect of an ACE-inhibitor based treatment regimen in patients with vascular disease or high risk of vascular disease: A combined analysis of individual data of ADVANCE, EUROPA, and PROGRESS trials

AimsAngiotensin-converting enzyme (ACE) inhibitors have been shown to reduce cardiovascular risk in different groups of patients. Whether these effects can be generalized to the broad group of patients with vascular disease is unknown. Therefore, we undertook a combined analysis using individual data from ADVANCE, EUROPA, and PROGRESS to determine the consistency of the treatment effect of perindopril-based regimen in patients with vascular disease or at high risk of vascular disease.Methods and resultsWe studied all-cause mortality and major cardiovascular outcomes during a follow-up of about 4 years in the 29 463 patients randomly assigned a perindopril-based treatment regimen or placebo. The perindopril-based regimens were associated with a significant reduction in all-cause mortality [hazard ratio (HR) 0.89; 95 confidence interval (CI) 0.82-0.96; P = 0.006], cardiovascular mortality (HR 0.85; 95 CI 0.76-0.95; P = 0.004), non-fatal myocardial infarction (HR 0.80; 95 CI 0.71-0.90; P < 0.001), stroke (HR 0.82; 95 CI 0.74-0.92; P = 0.002), and heart failure (HR 0.84; 95 CI 0.72-0.96; P = 0.015). Results were consistent in subgroups with different clinical characteristics, concomitant medication use, and across all strata of baseline blood pressure.ConclusionThis study provides strong evidence for a consistent cardiovascular protection with an ACE-inhibitor treatment regimen (perindopril-indapamide) by improving survival and reducing the risk of major cardiovascular events across a broad spectrum of patients with vascular disease

Randomized trial of an intensified, multifactorial intervention in patients with advanced‐stage diabetic kidney disease: Diabetic Nephropathy Remission and Regression Team Trial in Japan (DNETT‐Japan)

Aims/Introduction We evaluated the efficacy of multifactorial intensive treatment (IT) on renal outcomes in patients with type 2 diabetes and advanced‐stage diabetic kidney disease (DKD). Materials and Methods The Diabetic Nephropathy Remission and Regression Team Trial in Japan (DNETT‐Japan) is a multicenter, open‐label, randomized controlled trial with a 5‐year follow‐up period. We randomly assigned 164 patients with advanced‐stage diabetic kidney disease (urinary albumin‐to‐creatinine ratio ≥300 mg/g creatinine, serum creatinine level 1.2–2.5 mg/dL in men and 1.0–2.5 mg/dL in women) to receive either IT or conventional treatment. The primary composite outcome was end‐stage kidney failure, doubling of serum creatinine or death from any cause, which was assessed in the intention‐to‐treat population. Results The IT tended to reduce the risk of primary end‐points as compared with conventional treatment, but the difference between treatment groups did not reach the statistically significant level (hazard ratio 0.69, 95% confidence interval 0.43–1.11; P = 0.13). Meanwhile, the decrease in serum low‐density lipoprotein cholesterol level and the use of statin were significantly associated with the decrease in primary outcome (hazard ratio 1.14; 95% confidence interval 1.05–1.23, P Conclusions The risk of kidney events tended to decrease by IT, although it was not statistically significant. Lipid control using statin was associated with a lower risk of adverse kidney events. Further follow‐up study might show the effect of IT in patients with advanced diabetic kidney disease