Halting the Metabolic Complications of Antipsychotic Medication in Patients with a First Episode of Psychosis: How Far Can We Go with the Mediterranean Diet? A Pilot Study

The impacts of antipsychotic medications on eating-related outcomes: A mixed methods systematic review

BACKGROUND

Almost all antipsychotics are associated with weight gain. Given the gravity of this side-effect and its consequences, it is imperative to understand the mechanisms involved. One mechanism that could contribute to this side effect is the impact of antipsychotics on eating-related outcomes.

OBJECTIVE

We aimed to synthesise the available quantitative research on the effects of first- and second-generation antipsychotics on eating-related outcomes, and qualitative research exploring people's experiences with these medications in relation to appetite and eating behaviours (PROSPERO protocol CRD42022340211).

METHODS

We searched Medline, PsycInfo, and Web of Science from inception to 9 May 2024. Quantitative data were synthesised without meta-analysis using vote counting based on direction of effect. Qualitative data were synthesised using thematic synthesis.

RESULTS

Searches identified 8,746 citations yielding 61 separate studies; 55 quantitative and 6 qualitative, published 1982-2024. Using GRADE, our assessment of the quantitative review findings ranged from low to very low-level certainty. Given the lack of direct evidence from high-quality placebo-controlled trials, it is pertinent to interpret the quantitative findings with caution. Using GRADE-CERQual, our assessment of the qualitative review findings ranged from low to very low-level certainty; these findings suggest that the relationship between antipsychotics and food intake is influenced by an interplay of individual, interpersonal and external factors, the most significant of which is food environment.

LIMITATIONS

The internal validity of this review was affected by the serious limitations of the included quantitative studies and the paucity of qualitative evidence.

STRENGTHS

We used GRADE and GRADE-CERQual frameworks to enhance the transparency of our judgement of the certainty of the evidence. Lived experience perspectives were incorporated in different stages of the review to enhance its relevance and practical implications.

CONCLUSIONS

There is insufficient evidence from well-conducted studies to determine the effect of antipsychotics on eating-related outcomes.

Relevance of diet in schizophrenia: a review focusing on prenatal nutritional deficiency, obesity, oxidative stress and inflammation

BACKGROUND/OBJECTIVES

Schizophrenia is a complex mental disorder influenced by genetic and environmental factors, including dietary habits. Oxidative stress and inflammation play a crucial role in the pathophysiology of schizophrenia. Emerging research suggests that diet may affect schizophrenia through different biological mechanisms beyond oxidative stress and inflammation. In particular, epigenetic changes may alter the expression of genes related to neurodevelopment and neurotransmitter systems, while neuroplasticity plays a crucial role in brain adaptation and resilience to psychiatric disorders.

METHODS

The literature search included the main available databases (Science Direct, PubMed and Google Scholar), considering the English language, and our screening was performed based on several words such as "schizophrenia", "diet", "nutrients", "obesity", "oxidative stress", "inflammation", "antioxidants" and "prenatal nutritional deficiency". The review focused specifically on studies examining the relevance of diet in schizophrenia, as well as prenatal nutritional deficiency, obesity, oxidative stress, and inflammation associated with this disorder.

RESULTS

Following a review of the literature, it was found that nutritional deficiencies, including lack of omega-3 fatty acids, vitamins D, and B, during the prenatal and postnatal periods can have a negative impact on neurodevelopment and increase the risk of schizophrenia. Patients with schizophrenia have imbalances in antioxidant enzymes, such as glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), and reduced levels of antioxidants (vitamin E, vitamin C). These biochemical changes lead to an increase in markers of oxidative stress, including malondialdehyde (MDA). In addition, cytokine-mediated inflammation, microglial activation, and intestinal dysbiosis are associated with the onset of schizophrenia and the severity of schizophrenia symptoms. Currently, there is no universally accepted dietary regimen for control. However, various diets and nutritional methods are being researched and applied to alleviate the symptoms of schizophrenia and improve the overall health of patients, including the Mediterranean diet, the ketogenic diet, the gluten-free diet, and the DASH (Dietary Approaches to Stop Hypertension) diet.

CONCLUSION

A healthy diet, rich in anti-inflammatory nutrients and antioxidants, may help manage schizophrenia by reducing oxidative stress, preventing complications, and improving quality of life. Omega-3 fatty acids, vitamin D, and B vitamins are particularly important for brain development and function. In this review, we aim to analyze the literature on the influence of diet on schizophrenia, focusing on the role of prenatal nutritional deficiencies, obesity, oxidative stress, and inflammation.

Orlistat for the treatment of antipsychotic-induced weight gain: an eight-week multicenter, randomized, placebo-controlled, double-blind trial

BACKGROUND

Weight gain and metabolic disorders are commonly induced by antipsychotics. Orlistat is a lipase inhibitor used for weight control. The effect of orlistat on weight gain and metabolic disturbances in people (especially women) treated with antipsychotics has not been sufficiently studied. This study aimed to investigate the efficacy of orlistat in mitigating antipsychotic-induced weight gain and abnormal glycolipid metabolism.

METHODS

Patients with schizophrenia or bipolar disorder with a weight gain ≥ 7% after taking antipsychotics were recruited. Participants were randomly allocated to two groups: one received eight weeks of orlistat (360 mg/day) and the other received a placebo. Anthropometric and fasting serum biochemical parameters were measured at baseline, week 4 and week 8.

RESULTS

Sixty individuals (orlistat:placebo = 32:28) participated in the study. After controlling for the study center, the eight-week changes in body mass index (BMI), cholesterol (CHOL), high-density lipoprotein cholesterol (HDL-CH) and low-density lipoprotein cholesterol (LDL-CH) were significantly different between the groups. According to the mixed linear models, CHOL and LDL-CH were significantly lower in the orlistat group than in the control group at week 8. The week 0-to-8 slopes of BMI, CHOL and LDL-CH were also significantly lower in the orlistat group.

CONCLUSIONS

These findings suggested that orlistat is an effective intervention for attenuating weight gain and serum lipid disturbances in antipsychotic-treated patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03451734.

An association between PPARα-L162V polymorphism and increased plasma LDL cholesterol levels after risperidone treatment

Peroxisome proliferator-activated receptor alpha (PPARα) and antipsychotic medications both influence polyunsaturated fatty acids (PUFA) homeostasis, and thus PPARα polymorphism may be linked to antipsychotic treatment response. Here we investigated whether the functional leucine 162 valine (L162V) polymorphism in PPARα influenced antipsychotic treatment in a group of psychosis patients (N = 186), as well as in a patient subgroup with risperidone, paliperidone, or combination treatment (N = 65). Antipsychotic-naïve first-episode patients and nonadherent chronic individuals were genotyped by polymerase chain reaction analysis. At baseline, and after 8 weeks of treatment with various antipsychotic medications, we assessed the patients' Positive and Negative Syndrome Scale (PANSS) scores; PANSS factors; and metabolic syndrome-related parameters, including fasting plasma lipid and glucose levels, and body mass index. In the total patient group, PPARα polymorphism did not affect PANSS psychopathology or metabolic parameters. However, in the subgroup of patients with risperidone, paliperidone, or combination treatment, PPARα polymorphism influenced changes in plasma LDL cholesterol. Specifically, compared to PPARα-L162L homozygous patients, PPARα-L162V heterozygous individuals exhibited significantly higher increases of LDL cholesterol levels after antipsychotic treatment. The PPARα polymorphism had a strong effect size, but a relatively weak contribution to LDL cholesterol level variations (∼12.8 %).

Non-Classical Aspects of Obesity Pathogenesis and Their Relative Clinical Importance for Obesity Treatment

Obesity is a chronic disease and a major public health problem due to its association with non-communicable diseases and all-cause mortality. An increased energy intake and decreased physical activity have been long recognized as the classical parameters that contribute to the development of obesity. However, several other, non-classical factors have also been associated with obesity through various complex mechanisms. Some of them are diet related, such as diet quality, dietary habits and speed of eating. Other factors are non-dietary, such as endocrine-disrupting chemicals, sleep quality and quantity, psychotropic medications and light at night. The scope of the present narrative review is to address these non-classical factors that are implicated in the pathogenesis of obesity, to clarify their potential role in the management of obesity and, where possible, to provide some practical clinical recommendations.