In an observational investigation of adults receiving treatment with second-generation antipsychotics, researchers identified a significant link between an evening chronotype and increased psychiatric symptom severity, specifically among individuals diagnosed with bipolar disorder. The multicentre cross-sectional study evaluated 107 Italian adults between 18 and 65 years of age diagnosed with either schizophrenia spectrum disorders or bipolar disorders. While lifestyle patterns such as circadian rhythms and dietary choices are increasingly studied as potential determinants of mental health, their exact contributions across diagnostic categories have remained unclear.
The participants were treated with second-generation antipsychotics.
Chronotype was assessed using the reduced Morningness–Eveningness Questionnaire. Mediterranean diet adherence was assessed using the 14-item Prevención con Dieta Mediterránea questionnaire. Concurrently, psychiatric symptoms were measured through clinical evaluations utilizing the Brief Psychiatric Rating Scale.
Analysis of dietary habits demonstrated that the overall participant cohort maintained moderate adherence to the Mediterranean diet. The distribution of adherence scores remained generally similar across participants diagnosed with schizophrenia spectrum disorders and those diagnosed with bipolar disorders. Upon examining specific nutritional categories within the assessment tool, the investigators found that low consumption of fruit, fish, and nuts represented the primary dietary gaps among the evaluated adults.
When assessing the relationship between nutrition and clinical status, bivariate evaluations initially indicated a trend toward an inverse correlation between Mediterranean diet adherence and psychiatric symptom severity. However, this potential association did not retain statistical significance after entering multivariable linear regression models that controlled for confounding variables, including age, body mass index, sex, and psychiatric diagnosis. Consequently, independent dietary adherence was not statistically related to overall symptom scores in the adjusted framework.
In contrast to dietary measures, circadian timing revealed distinct, diagnosis-dependent variations in symptom expression. The multivariable linear regression analysis demonstrated a statistically significant interaction between patient diagnosis and chronotype (p = 0.016). When examining the cohorts separately, a preference for eveningness correlated significantly with greater psychiatric symptom severity among participants with bipolar disorder (Spearman rho = −0.451, p = 0.014). This correlation was not observed in the cohort diagnosed with schizophrenia spectrum disorders.
The cross-sectional nature of the investigation presents inherent methodological constraints, precluding any determination of causality between evening circadian preferences and elevated psychiatric symptoms. The authors concluded that chronotype assessments and targeted lifestyle modifications may serve as relevant supplementary considerations alongside standard clinical care for these populations.
Although overall adherence to the Mediterranean dietary pattern did not reach statistical significance as an independent predictor of symptom severity in the adjusted regression framework, the specific nutritional deficits identified by the research group highlight practical focal points for clinical attention.
Subject of Research: Association of circadian chronotype and Mediterranean diet adherence with psychiatric symptom severity in adults treated with second-generation antipsychotics
Article Title: Association of Mediterranean diet adherence and chronotype with psychiatric symptom severity in adults treated with second-generation antipsychotics: a cross-sectional study
Article References: Vetrani, C., Magno, M., Tripoli, G., Scaglione, A., Daino, M., Giammanco, A., Caselani, E., Martella, D., Gaggianesi, M., Bella, S. D., Camillo, L., Corti, B., Pozzi, M., Nobile, M., Cascia, C. L., Colao, A., de Bartolomeis, A., de Girolamo, G., Macchia, P. E., … Tura, G. B. (2026). Association of Mediterranean diet adherence and chronotype with psychiatric symptom severity in adults treated with second-generation antipsychotics: a cross-sectional study. Journal of Translational Medicine. https://doi.org/10.1186/s12967-026-09171-1
Image Credits: AI Generated
DOI: 10.1186/s12967-026-09171-1
Keywords: bipolar disorder, schizophrenia spectrum disorders, chronotype, eveningness, second-generation antipsychotics, Mediterranean diet, PREDIMED questionnaire, reduced Morningness-Eveningness Questionnaire, Brief Psychiatric Rating Scale, psychiatric symptom severity, circadian rhythms, multicentre study, cross-sectional study, lifestyle factors, mental health, RISKMet Consortium
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