Low dietary intakes of the n-3 long-chain PUFA (LCPUFA) EPA and DHA are thought to be associated with increased risk for a variety of adverse outcomes, including some psychiatric disorders. Evidence from observational and intervention studies for a role of n-3 LCPUFA in depression is mixed, with some support for a benefit of EPA and/or DHA in major depressive illness. The present study was a double-blind randomised controlled trial that evaluated the effects of EPA þ DHA supplementation (1·5 g/d) on mood and cognitive function in mild to moderately depressed individuals. Of 218 participants who entered the trial, 190 completed the planned 12 weeks intervention. Compliance, confirmed by plasma fatty acid concentrations, was good, but there was no evidence of a difference between supplemented and placebo groups in the primary outcomenamely, the depression subscale of the Depression Anxiety and Stress Scales at 12 weeks. Mean depression score was 8·4 for the EPA þ DHA group and 9·6 for the placebo group, with an adjusted difference of 21·0 (95 % CI 22·8, 0·8; P¼ 0·27). Other measures of mood, mental health and cognitive function, including Beck Depression Inventory score and attentional bias toward threat words, were similarly little affected by the intervention. In conclusion, substantially increasing EPA þ DHA intake for 3 months was found not to have beneficial or harmful effects on mood in mild to moderate depression. Adding the present result to a meta-analysis of previous relevant randomised controlled trial results confirmed an overall negligible benefit of n-3 LCPUFA supplementation for depressed mood.

Trial evidence that examines the effects of n-3 PUFAs on depressed mood is limited and is difficult to summarize and evaluate because of considerable heterogeneity. The evidence available provides little support for the use of n-3 PUFAs to improve depressed mood. Larger trials with adequate power to detect clinically important benefits are required.

The findings provide strong support for the withdrawal reversal hypothesis. In particular, cognitive performance was found to be affected adversely by acute caffeine withdrawal and, even in the context of alertness lowered by sleep restriction, cognitive performance was not improved by caffeine in the absence of these withdrawal effects. Different patterns of effects (or lack of effects) of caffeine and caffeine withdrawal were found for other variables, but overall these results also suggest that there is little benefit to be gained from caffeine consumption.

A second cup-of-coffee equivalent dose of caffeine only reliably affected cognitive performance and mood after an 8-h interval between doses, but not after shorter intervals (when caffeine had some adverse effects). These results show that, apart from caffeine consumption soon after waking, the daily pattern of caffeine intake of many typical caffeine consumers is not well explained by the short-term psychostimulant effects of caffeine.

No abstract

No effect of n-3 long-chain polyunsaturated fatty acid (EPA and DHA) supplementation on depressed mood and cognitive function: a randomised controlled trial -reply by Rogers et al.

Lay beliefs about the importance of 24 different contributors to overcoming 4 disorders that constitute primarily cognitive deficits were studied. A meta-analysis of previous programmatic studies in the area was performed so that 22 different psychological problems could be compared. In the present study, 107 participants completed a questionnaire indicating how effective 24 factors were in overcoming 4 specific problems: dyslexia, fear of flying, amnesia, and learning difficulties. Factor analysis revealed almost identical clusters (inner control, social consequences, understanding, receiving help, and fate) for each problem. The perceived relevance of those factors differed significantly between problems. Some individual difference factors (sex and religion) were found to predict certain factor attributions for specific disorders. A meta-analysis of the 5 studies in this series yielded a 6-factor structure comparable to those of the individual studies and provided results indicating the benefits and limitations of this kind of investigation. The clinical relevance of studying attributions for cure is considered.

OBJECTIVES To investigate whether there were important differences in uptake of NICE clinical guidelines according to diabetes mellitus type in England and Wales from 2013 to 2018, test the hypothesis that guidelines are more successfully implemented with T2DM than T1DM, and explore possible explanations for differences. DESIGN Retrospective cross-sectional analyses of aggregated patient level data from the National Diabetes Audit (NDA) dataset owned by NHS Digital and commissioned by Healthcare Quality Improvement Partnership. SETTING Diabetes specialist services, primary care (GP surgeries submitting NDA data) across England and Wales. PARTICIPANTS 1 739 175 patients with diabetes aged ≥20 in England and Wales in 2013-14, 1 871 320 individual patients in 2014-15, 2 688 106 individual patients in 2015-16, 3 095 275 individual patients in 2016-17, and 3 357 055 individual patients in 2017-18. INTERVENTIONS Recommended care for diabetes mellitus as outlined in relevant NICE guidelines and delivered by either specialist clinicians or GPs. MAIN OUTCOME MEASURES The recorded attainment of NICE treatment targets: HbA1c levels =<7.5% (58.5 mmol/mol), blood pressure <140/80mmHg, blood cholesterol <5mmol/l; and clinical processes: at least annual monitoring of HbA1c, blood pressure, cholesterol, albumin:creatinine ratio, smoking status, Body Mass Index. RESULTS Annual collections (2013-14, 2014-15, 2015-16, 2016-17 and 2017-18) were individually analysed, testing associations between diabetes type and attainment of clinical targets or processes using a multivariable logistic regression model, adjusted for age and sex. Increased odds of meeting clinical targets if patients had T2DM compared with T1DM was consistent across the five years, except for cholesterol levels <5mmol/l where T2DM patients had lower odds (all associations p<.0001). Greatest differences in all five years between T1DM and T2DM was observed with patients meeting the HbA1c=<7.5% target, the largest being in 2015-16 (Odds Ratio 3.43, 95% confidence interval 3.39 to 3.47). CONCLUSIONS The differences between T1DM and T2DM in HbA1c target attainment is key and potentially reflects challenges of managing T1DM with insulin but suggests a point of focus for that patient population. Other important elements for consideration could be specific setting for delivery (primary care versus secondary care) and duration of illness.