Longitudinal investigation of the relationship between omega-3 polyunsaturated fatty acids and neuropsychological functioning in recent-onset psychosis: A randomized clinical trial

Nutraceuticals in Psychiatric Disorders: A Systematic Review

Correct nutrition and diet are directly correlated with mental health, functions of the immune system, and gut microbiota composition. Diets with a high content of some nutrients, such as fibers, phytochemicals, and short-chain fatty acids (omega-3 fatty acids), seem to have an anti-inflammatory and protective action on the nervous system. Among nutraceuticals, supplementation of probiotics and omega-3 fatty acids plays a role in improving symptoms of several mental disorders. In this review, we collect data on the efficacy of nutraceuticals in patients with schizophrenia, autism spectrum disorders, major depression, bipolar disorder, and personality disorders. This narrative review aims to provide an overview of recent evidence obtained on this topic, pointing out the direction for future research.

New perspectives on randomized controlled trials with omega-3 fatty acid supplements and cognition: A scoping review

Long chain polyunsaturated omega-3 fatty acids (n-3 FA), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are known to be important components in a healthy diet and contribute to healthy functioning of the heart and the brain, among other organs. Although there are epidemiological studies on the strong relationship between fish or n-3 FA consumption and lower risk of cognitive decline, results from randomized controlled trials (RCTs) are less consistent. Here, we performed a scoping review on RCTs with n-3 FA supplementation where cognition was evaluated. Seventy-eight RCTs published before April 2022 were included in this review. Among these RCTs, 43.6% reported a positive cognitive outcome after the consumption of n-3 FA compared to the placebo. However, there was a large diversity of populations studied (age ranges and health status), wide range of doses of EPA + DHA supplemented (79 mg/day - 5200 mg/day) and a multitude of tests evaluating cognition, mainly diagnostic tests, that were used to assess cognitive scores and overall cognitive status. RCTs were thereafter categorized into non-cognitively impaired middle-aged adults (n = 24), non-cognitively impaired older adults (n = 24), adults with subjective memory complaints (n = 14), adults with mild cognitive impairments (MCI, n = 9) and people with diagnosed dementia or other cognitive changes (n = 7). Among these categories, 66.7% of RCTs conducted with MCI adults reported a positive cognitive outcome when supplemented with n-3 FA vs. the placebo. Therefore, this scoping review provides rationale and questions to a) strengthen the design of future RCTs with n-3 FA for cognitive outcomes, and b) generate more informative data to support clinicians in their practice in assessing cognition before and after a nutritional intervention.

Effects of Fish-Oil Consumption on Psychological Function Outcomes in Psychosis: A Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials

Research on the effects of fish oil on clinical symptoms and psychosocial functioning in people with psychosis has been inconsistent. We conducted this systematic review and meta-analysis to summarize the available data on the effects of oral intake of fish oil on psychological functioning in patients with psychosis. Three online databases including PubMed, Scopus, and Web of Science were searched to identify relevant studies published by April 2021. The exposure was oral fish-oil supplementation. The Positive and Negative Syndrome Scale (PANSS), the Brief Psychiatric Rating Scale (BPRS), and the Global Assessment of Functioning (GAF) were our outcome measures. Seventeen randomized clinical trials involving 1390 patients were included. No change in PANSS was observed following oral fish-oil intake [weighted mean difference (WMD): -0.87; 95% CI: -16.99, 15.26; P = 0.92]. In a nonlinear dose-response analysis, a significant inverse association was observed between <10 wk of fish-oil supplementation and PANSS (WMD: -10; P-nonlinearity = 0.02). Although analysis of 4 studies showed a nonsignificant reduction in BPRS after fish-oil intake (WMD: -2.990; 95% CI: -6.42, 0.44; P = 0.08), a nonlinear dose-response analysis revealed significant inverse associations between dose (>2200 mg/d) and duration of fish-oil supplementation (<15 wk) with BPRS score (WMD: -8; P-nonlinearity = 0.04). Combined effect sizes from 6 randomized clinical trials showed significant increases in GAF after oral administration of fish oil (WMD: 6.66; 95% CI: 3.39, 9.93; P < 0.001). In conclusion, we did not find any significant changes in PANSS and BPRS scores following fish-oil supplementation. Nevertheless, oral fish-oil intake significantly contributed to improvement in GAF scores. This is the first meta-analysis to examine the effects of fish oil on the psychological functioning scores of PANSS, BPRS, and GAF simultaneously.

Comparative plasma metabolomic analysis to identify biomarkers for lead-induced cognitive impairment

BACKGROUND

Lead (Pb), an environmental neurotoxicant, is known to induce cognitive impairment. Neuroinflammation and oxidative stress in the brain tissue are common pathogenetic links to Pb-induced cognitive impairment. There are no existing biomarkers to evaluate Pb-reduced cognition. Plasma metabolites are the readout of the biological functions of the host, making it a potential biomarker for assessing heavy metal-induced cognitive impairment.

METHODS

The present report aims to identify the plasma metabolite changes under conditions of high plasma Pb levels and low cognition.

RESULTS

We conducted a comparative plasma metabolomic analysis on two groups of adults those with low plasma Pb level and high cognition vs. those with high plasma Pb level and low cognition and identified 20 dysregulated metabolites. In addition, we found a significant reduction in docosahexaenoic acid, glycoursodeoxycholic acid, and arachidonic acid, and significant induction of p-cresol sulfate and phenylacetyl-l-glutamine. Gene Ontology enrichment analysis highlighted the importance of these plasma metabolites in brain functions and neurodegenerative diseases such as Parkinson's disease.

CONCLUSIONS

The findings of this report provide novel insights into the use of plasma metabolites to assess metal-induced cognitive impairment.

Unhealthy diet in schizophrenia spectrum disorders

PURPOSE OF REVIEW

The high mortality and prevalence of metabolic syndrome in patients with schizophrenia spectrum disorders (SSD) is maintained by poor diet. This narrative review summarizes recent literature to provide a reflection of current eating habits, dietary preferences, and nutritional status of SSD patients. Elucidating these factors provides new insights for potential lifestyle treatment strategies for SSD.

RECENT FINDINGS

Only 10.7% of the SSD patients had a healthy dietary pattern, against 23% of the general population. The dietic component of the Keeping the Body in Mind Xtend lifestyle program increased diet quality with 10% for young people with first-episode psychosis, compared to baseline, which was predominantly driven by increased vegetable variety and amounts.

SUMMARY

Recent findings render poor dietary habits as potential targets for treatment of SSD patients. Further studies into anti-inflammatory diets and associations with gut-brain biomarkers are warranted. When proven, structured and supervised diet interventions may help SSD patients escape from this entrapment, as only supplementing nutrients or providing dietary advice lacks the impact to significantly reduce the risk of chronic physical illnesses.