Vitamin E and Omega-3: What to believe: Observational studies or randomized controlled trials?

Background: Several monotherapy and augmentation strategies have been introduced to improve the treatment of schizophrenia. The benefits of omega-3 polyunsaturated fatty acids in patients with mental disorders is becoming increasingly acknowledged. However, its role in the treatment of schizophrenia raises complex considerations about which there has been little consensus. The aim of this study was to synthesize the findings of randomized controlled trials that were conducted to determine the efficacy and safety of omega-3 polyunsaturated fatty acids in patients with schizophrenia. Methods: The MEDLINE, Embase, Cochrane, Scopus, and Web of Science databases were searched for relevant literature. The primary outcome was changes in psychopathology and the secondary outcomes were changes in metabolic parameters and safety profiles. Results: Twenty double-blind randomized controlled trials in 1494 patients were included. Omega-3 polyunsaturated fatty acids augmentation was associated with significantly improved psychopathology in patients with schizophrenia, particularly general psychopathology and positive symptoms but not negative symptoms. Patients who were severely ill and received omega-3 polyunsaturated fatty acids containing eicosapentaenoic acid >1 g/d showed significant improvement. A favorable effect of omega-3 polyunsaturated fatty acids supplements on serum triglycerides was also demonstrated. Omega-3 polyunsaturated fatty acids are well-tolerated and safe in patients with schizophrenia. Conclusions: These findings tentatively support the use of omega-3 polyunsaturated fatty acids as a potential augmentation strategy in schizophrenia. Further research in larger samples is warranted to clarify the optimal dosage and the correct proportions of omega-3 polyunsaturated fatty acids to administer, together with elucidation of the underlying mechanisms.

Download Full-text

Omega-3 Fatty Acids in the Prevention of Atrial Fibrillation Recurrences after Cardioversion: A Meta-analysis of Randomized Controlled Trials

Internal Medicine ◽

10.2169/internalmedicine.51.7714 ◽

2012 ◽

Vol 51 (18) ◽

pp. 2503-2508 ◽

Cited By ~ 16

Author(s):

Hong Cao ◽

Xin Wang ◽

He Huang ◽

Shao Zhen Ying ◽

Yong Wei Gu ◽

...

Keyword(s):

Atrial Fibrillation ◽

Fatty Acids ◽

Randomized Controlled Trials ◽

Meta Analysis ◽

Controlled Trials ◽

Omega 3 Fatty Acids ◽

Omega 3 ◽

Randomized Controlled

Download Full-text

Effects of Omega-3 Fatty Acid Intake in Patients Undergoing Dialysis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Journal of the American College of Nutrition ◽

10.1080/07315724.2021.1953416 ◽

2021 ◽

pp. 1-16

Author(s):

Rui Liu ◽

Jiawei Jiang ◽

Zhangning Fu ◽

Chao Liu ◽

Linong Yao ◽

...

Keyword(s):

Systematic Review ◽

Fatty Acid ◽

Randomized Controlled Trials ◽

Meta Analysis ◽

Controlled Trials ◽

Fatty Acid Intake ◽

Omega 3 ◽

Omega 3 Fatty Acid ◽

Randomized Controlled ◽

Acid Intake

Download Full-text

High-cited favorable studies for COVID-19 treatments ineffective in large trials

10.1101/2022.01.11.22269097 ◽

2022 ◽

Author(s):

John P.A. Ioannidis

Keyword(s):

Clinical Trials ◽

Randomized Controlled Trials ◽

Clinical Studies ◽

Observational Studies ◽

Randomized Trials ◽

Controlled Trials ◽

Randomized Controlled ◽

Wide Dissemination ◽

Highly Cited Articles ◽

Highly Cited

Importance. COVID-19 has resulted in massive production, publication and wide dissemination of clinical studies trying to identify effective treatments. However, several widely touted treatments failed to show effectiveness in large well-done randomized controlled trials (RCTs). Objective. To evaluate for COVID-19 treatments that showed no benefits in subsequent large RCTs how many of their most-cited clinical studies had declared favorable results for these interventions. Methods. Scopus (last update December 23, 2021) identified articles on lopinavir-ritonavir, hydroxycholoroquine/azithromycin, remdesivir, convalescent plasma, colchicine or interferon (index interventions) that represented clinical trials and that had received >150 citations. Their conclusions were assessed and correlated with study design features. The ten most recent citations for the most-cited article on each index intervention were examined on whether they were critical to the highly-cited study. Altmetric scores were also obtained. Findings. 40 articles of clinical studies on these index interventions had received >150 citations (7 exceeded 1,000 citations). 20/40 (50%) had favorable conclusions and 4 were equivocal. Highly-cited articles with favorable conclusions were rarely RCTs while those without favorable conclusions were mostly RCTs (3/20 vs 15/20, p=0.0003). Only 1 RCT with favorable conclusions had sample size >160. Citation counts correlated strongly with Altmetric scores, in particular news items. Only 9 (15%) of 60 recent citations to the most highly-cited studies with favorable or equivocal conclusions were critical to the highly-cited study. Conclusion. Many clinical studies with favorable conclusions for largely ineffective COVID-19 treatments are uncritically heavily cited and disseminated. Early observational studies and small randomized trials may cause spurious claims of effectiveness that get perpetuated.

Download Full-text

Impact of Ramadan Diurnal Intermittent Fasting on Hypoglycemic Events in Patients With Type 2 Diabetes: A Systematic Review of Randomized Controlled Trials and Observational Studies

Frontiers in Endocrinology ◽

10.3389/fendo.2021.624423 ◽

2021 ◽

Vol 12 ◽

Author(s):

Dana Abdelrahim ◽

MoezAlIslam E. Faris ◽

Mohamed Hassanein ◽

Ayman Z. Shakir ◽

Ayesha M. Yusuf ◽

...

Keyword(s):

Systematic Review ◽

Type 2 Diabetes ◽

Randomized Controlled Trials ◽

Observational Studies ◽

Dietary Behaviors ◽

Controlled Trials ◽

Ramadan Fasting ◽

Randomized Controlled ◽

The Impact

Ramadan is the 9th month of the lunar calendar during which Muslims abstain from food and drink between dawn and sunset for 30 consecutive days. Ramadan fasting is observed by all healthy Muslim adults, as well many Muslims with type 2 diabetes (T2DM). Hypoglycemic events (HE) are a serious complication associated with diabetes management and are associated with increased cardiovascular disease risk. Conflicting results have been reported concerning the incidence of HE among people with T2DM observing Ramadan fasting. This review summarizes available scientific evidence on the occurrence of HE and the effects of different moderators on the incidence of HE among patients with T2DM during Ramadan. We conducted a systematic review of available observational studies and randomized controlled trials (RCTs) for patients with T2DM who fasted during Ramadan, with HE as the primary outcome. Ten databases were searched for relevant studies from inception until October 31, 2020. In total, 68 studies (35 RCTs and 33 observational studies) met the inclusion criteria. Non-sulfonylureas hypoglycemic medications showed superior effects in lowering the incidence of HE over sulfonylureas hypoglycemic medications. Variable moderators were associated with experiencing HE during Ramadan in both observational studies and RCTs, including sex, geographical location, body anthropometric indicators, season, dietary behaviors, fasting duration, time since diagnosis, and pre-fasting education. This comprehensive systematic review covered the largest number of observational and clinical studies investigating the impact of Ramadan on HE among patients with T2DM. The study highlights the significance of different moderators that influence the effect of Ramadan fasting on HE, including dietary behaviors, fasting time duration, sex, season, country, pre-fasting education, age, and time since diagnosis. The study also highlighted the impact of different hypoglycemic medications on HE and noted the superiority of non-sulfonylureas over sulfonylureas hypoglycemic medications in lowering the risk for hypoglycemia in people with T2DM during Ramadan fasting.

Download Full-text