Considerable controversy exists regarding the association of omega-3 polyunsaturated fatty acids (PUFAs) and major cardiovascular end points.
To assess the role of omega-3 supplementation on major ...cardiovascular outcomes.
MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials through August 2012.
Randomized clinical trials evaluating the effect of omega-3 on all-cause mortality, cardiac death, sudden death, myocardial infarction, and stroke.
Descriptive and quantitative information was extracted; absolute and relative risk (RR) estimates were synthesized under a random-effects model. Heterogeneity was assessed using the Q statistic and I2. Subgroup analyses were performed for the presence of blinding, the prevention settings, and patients with implantable cardioverter-defibrillators, and meta-regression analyses were performed for the omega-3 dose. A statistical significance threshold of .0063 was assumed after adjustment for multiple comparisons.
Of the 3635 citations retrieved, 20 studies of 68,680 patients were included, reporting 7044 deaths, 3993 cardiac deaths, 1150 sudden deaths, 1837 myocardial infarctions, and 1490 strokes. No statistically significant association was observed with all-cause mortality (RR, 0.96; 95% CI, 0.91 to 1.02; risk reduction RD -0.004, 95% CI, -0.01 to 0.02), cardiac death (RR, 0.91; 95% CI, 0.85 to 0.98; RD, -0.01; 95% CI, -0.02 to 0.00), sudden death (RR, 0.87; 95% CI, 0.75 to 1.01; RD, -0.003; 95% CI, -0.012 to 0.006), myocardial infarction (RR, 0.89; 95% CI, 0.76 to 1.04; RD, -0.002; 95% CI, -0.007 to 0.002), and stroke (RR, 1.05; 95% CI, 0.93 to 1.18; RD, 0.001; 95% CI, -0.002 to 0.004) when all supplement studies were considered.
Overall, omega-3 PUFA supplementation was not associated with a lower risk of all-cause mortality, cardiac death, sudden death, myocardial infarction, or stroke based on relative and absolute measures of association.
There is evidence that diet and nutrition are modifiable risk factors for several cancers, but associations may be flawed due to inherent biases. Nutritional epidemiology studies have largely relied ...on a single assessment of diet using food frequency questionnaires. We conduct an umbrella review of meta-analyses of observational studies to evaluate the strength and validity of the evidence for the association between food/nutrient intake and risk of developing or dying from 11 primary cancers. It is estimated that only few single food/nutrient and cancer associations are supported by strong or highly suggestive meta-analytic evidence, and future similar research is unlikely to change this evidence. Alcohol consumption is positively associated with risk of postmenopausal breast, colorectal, esophageal, head & neck and liver cancer. Consumption of dairy products, milk, calcium and wholegrains are inversely associated with colorectal cancer risk. Coffee consumption is inversely associated with risk of liver cancer and skin basal cell carcinoma.
Objectives To summarise the evidence and evaluate the validity of the associations between type 2 diabetes and the risk of developing or dying from cancer.Design An umbrella review of the evidence ...across meta-analyses of observational studies of type 2 diabetes with risk of developing or dying from any cancer.Data sources PubMed, Embase, Cochrane database of systematic reviews, and manual screening of references.Eligibility criteria Meta-analyses or systematic reviews of observational studies in humans that examined the association between type 2 diabetes and risk of developing or dying from cancer.Results Eligible meta-analyses assessed associations between type 2 diabetes and risk of developing cancer in 20 sites and mortality for seven cancer sites. The summary random effects estimates were significant at P=0.05 in 20 meta-analyses (74%); and all reported increased risks of developing cancer for participants with versus without diabetes. Of the 27 meta-analyses, eventually only seven (26%) compiled evidence on more than 1000 cases, had significant summary associations at P≤0.001 for both random and fixed effects calculations, and had neither evidence of small study effects nor evidence for excess significance. Of those, only six (22%) did not have substantial heterogeneity (I2>75%), pertaining to associations between type 2 diabetes and risk of developing breast, cholangiocarcinoma (both intrahepatic and extrahepatic), colorectal, endometrial, and gallbladder cancer. The 95% prediction intervals excluded the null value for four of these associations (breast, intrahepatic cholangiocarcinoma, colorectal, and endometrial cancer).Conclusions Though type 2 diabetes has been extensively studied in relation to risk of developing cancer and cancer mortality and strong claims of significance exist for most of the studied associations, only a minority of these associations have robust supporting evidence without hints of bias.
Intravitreal chemotherapy is used as a salvage therapy for retinoblastoma with persistent or recurrent vitreous seeding after primary treatment. To assess the safety of this technique, we conducted a ...systematic review of all studies reporting ocular toxicity data. Forty-eight trials involving 2751 eyes were included. The most common complications were cataract, retinal toxicity, and vitreous hemorrhage. However, severe and permanent adverse events were limited, while the risk of extraocular dissemination, a significant concern, was practically eliminated through preventive techniques. Globe salvage rates ranged from 29 % to 100 %. In conclusion, intravitreal chemotherapy seems to improve prognosis of eyes with advanced disease, with an acceptable safety profile. Nevertheless, most relevant studies are retrospective, and no randomized trials have been performed. Recognizing the challenges regarding the conduct of randomized studies for such a rare pediatric cancer, we believe that multicenter trials through international collaborations can significantly enhance the available information.
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•Intravitreal chemotherapy is a treatment for retinoblastoma with vitreous seeding.•Globe salvage rates range from 29 % to 100 % in various clinical series.•Retinal toxicity, cataract and vitreous hemorrhage are the most common side effects.•Extraocular tumor spread risk is minimized through preventive techniques.•Multicenter randomized trials are needed to strengthen the available evidence.
With the exception of renal cell carcinoma, studies assessing the association between hypertension and other cancers are inconsistent. We conducted a meta-analysis to assess this evidence. We ...included observational studies investigating the association between any definition of hypertension or systolic and diastolic blood pressure and risk of any cancer, after searching PubMed until November 2017. We calculated summary relative risks (RR) and 95% confidence intervals (CI) using inverse-variance weighted random effects methods. A total of 148 eligible publications were identified out of 39,891 initially screened citations. Considering only evidence from 85 prospective studies, positive associations were observed between hypertension and kidney, colorectal and breast cancer. Positive associations between hypertension and risk of oesophageal adenocarcinoma and squamous cell carcinoma, liver and endometrial cancer were also observed, but the majority of studies did not perform comprehensive multivariable adjustments. Systolic and diastolic blood pressure were positively associated with risk of kidney cancer but not with other cancers. In addition to the previously well-described association between hypertension and risk of kidney cancer, the current meta-analysis suggested that hypertensive individuals may also be at higher risk of colorectal and breast cancer. However, careful interpretation is required as most meta-analyses included relatively small number of studies, several relative risks had weak or moderate magnitude and maybe affected by residual confounding.
Diabetes mellitus has a multifactorial pathogenesis with a strong genetic component as well as many environmental and lifestyle influences. Emerging evidence suggests that environmental contaminants, ...including pesticides, might play an important role in the pathogenesis of diabetes.
We performed a systematic review and meta-analysis of observational studies that assessed the association between exposure to pesticides and diabetes and we examined the presence of heterogeneity and biases across available studies.
A comprehensive literature search of peer-reviewed original research pertaining to pesticide exposure and diabetes, published until 30st May 2015, with no language restriction, was conducted. Eligible studies were those that investigated potential associations between pesticides and diabetes without restrictions on diabetes type. We included cohort studies, case–control studies and cross-sectional studies. We extracted information on study characteristics, type of pesticide assessed, exposure assessment, outcome definition, effect estimate and sample size.
We identified 22 studies assessing the association between pesticides and diabetes. The summary OR for the association of top vs. bottom tertile of exposure to any type of pesticide and diabetes was 1.58 (95% CI: 1.32–1.90, p=1.21×10−6), with large heterogeneity (I2=66.8%). Studies evaluating Type 2 diabetes in particular (n=13 studies), showed a similar summary effect comparing top vs. bottom tertiles of exposure: 1.61 (95% CI 1.37–1.88, p=3.51×10−9) with no heterogeneity (I2=0%). Analysis by type of pesticide yielded an increased risk of diabetes for DDE, heptachlor, HCB, DDT, and trans-nonachlor or chlordane.
The epidemiological evidence, supported by mechanistic studies, suggests an association between exposure to organochlorine pesticides and Type 2 diabetes.
•A systematic review identified 22 studies on pesticides and type 2 diabetes•Data suggests an association between organochlorine exposure and type 2 diabetes•DDE, heptachlor, HCB, DDT, and trans-nonachlor show similar associations with type 2 diabetes•Mechanistic studies support a link between organochlorines and insulin resistance
COPD has been perceived as being a disease of older men. However, >7 million women are estimated to live with COPD in the USA alone. Despite a growing body of literature suggesting an increasing ...burden of COPD in women, the evidence is limited.
To assess and synthesize the available evidence among population-based epidemiologic studies and calculate the global prevalence of COPD in men and women.
A systematic review and meta-analysis reporting gender-specific prevalence of COPD was undertaken. Gender-specific prevalence estimates were abstracted from relevant studies. Associated patient characteristics as well as custom variables pertaining to the diagnostic method and other important epidemiologic covariates were also collected. A Bayesian random-effects meta-analysis was performed investigating gender-specific prevalence of COPD stratified by age, geography, calendar time, study setting, diagnostic method, and disease severity.
Among 194 eligible studies, summary prevalence was 9.23% (95% credible interval CrI: 8.16%-10.36%) in men and 6.16% (95% CrI: 5.41%-6.95%) in women. Gender prevalences varied widely by the World Health Organization Global Burden of Disease subregions, with the highest female prevalence found in North America (8.07% vs 7.30%) and in participants in urban settings (13.03% vs 8.34%). Meta-regression indicated that age ≥40 and bronchodilator testing contributed most significantly to heterogeneity of prevalence estimates across studies.
We conducted the largest ever systematic review and meta-analysis of global prevalence of COPD and the first large gender-specific review. These results will increase awareness of COPD as a critical woman's health issue.
Omega-3 supplements are popular for cardiovascular disease (CVD) prevention. We aimed to assess the association between dose-specific omega-3 supplementation and CVD outcomes.
We included ...double-blind randomised clinical trials with duration ≥1 year assessing omega-3 supplementation and estimated the relative risk (RR) for all-cause mortality, cardiac death, sudden death, myocardial infarction and stroke. Primary analysis was a stratified random-effects meta-analysis by omega-3 dose in 4 a priori defined categories (<1, 1, 2, ≥3 of 1 g capsules/day). Complementary approaches were trial sequential analysis and sensitivity analyses for triglycerides, prevention setting, intention-to-treat analysis, eicosapentaenoic acid, sample size, statin use, study duration.
Seventeen studies (n=83 617) were included. Omega-3 supplementation as ≤1 capsule/day was not associated with any outcome under study; futility boundaries were crossed for all-cause mortality and cardiac death. For two capsules/day, we observed a statistically significant reduction of cardiac death (n=3, RR 0.55, 95% CI 0.33 to 0.90, I
=0%); for ≥3 capsules/day we observed a statistically significant reduction of cardiac death (n=3, RR 0.82, 95% CI 0.68 to 0.99, I
=0%), sudden death (n=1, RR 0.70, 95% CI 0.51 to 0.97) and stroke (n=2, RR 0.74, 95% CI 0.57 to 0.95, I
=0%).
Omega-3 supplementation at <2 1 g capsules/day showed no association with CVD outcomes; this seems unlikely to change from future research. Compared with the robust scientific evidence available for low doses, the evidence for higher doses (2-4 1 g capsules/day) is weak. The emerging postulated benefit from high-dose supplementation needs replication and further evaluation as to the precise formulation and indication.
Patients with moderate-to-severe allergic rhinitis who are inadequately controlled despite treatment according to current rhinitis management guidelines have a significant unmet medical need. Such ...patients have a negative impact on daily functioning and are at risk of developing serious comorbidities, such as asthma and chronic rhinosinusitis.
To assess the efficacy and safety of omalizumab in poorly controlled allergic rhinitis under a meta-analysis framework.
MEDLINE and the Cochrane Central Register of Controlled Trials were searched through September 2013. Studies on the efficacy of omalizumab in allergic rhinitis that assessed clinical outcomes were selected. Descriptive and quantitative information was extracted; mean differences and relative risk estimates were synthesized under a fixed or random effects model. Heterogeneity was assessed by using the Q statistic and the I(2) metric. Subgroup analyses were performed for the presence of specific immunotherapy treatment.
Of the 352 citations retrieved, 11 studies of 2870 patients were finally included. A statistically significant reduction in the daily nasal symptom severity score (standardized mean difference -0.67 95% CI, -1.3 to -0.31; P < .0001; I(2), 92%) and a statistically significant reduction in daily nasal rescue medication score (-0.22 95% CI, -0.39 to -0.05; P = .01; I(2), 58%) were observed. There was not a statistically significant difference in the occurrence of any adverse event (relative risk 1.06 95% CI, 0.94-1.19; I(2), 55%).
Omalizumab is statistically significantly associated with symptom relief, decreased rescue medication use, and improvement of quality of life in patients with inadequately controlled allergic rhinosinusitis.
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