Animal-assisted therapy in patients with psychotic disorders: A systematic review and meta-analysis Ana María Peraile-Huerta, Estela Jiménez-López, Valentina Díaz-Goñi, Tomás Olivo Martins-de-Passos, Fernando Peral-Martínez, Sandra Herráiz-Garrote, Ana Pérez-Moreno, Arthur Eumann Mesas, Bruno Bizzozero-Peroni Complementary Therapies in Medicine, 2026 To synthesize the available evidence on the effects of animal-assisted therapy on core symptom dimensions (including positive, negative, and general symptoms), specific symptom domains (including depression, anhedonia, anxiety, stress) and cognitive functioning in patients with psychotic spectrum disorders. A systematic review and meta-analysis were conducted in accordance with the PRISMA and Cochrane Handbook for Systematic Reviews of Interventions guidelines. The PubMed, Cochrane Library, Web of Science and PsycINFO databases were searched from inception to June 2025 with no language restrictions. Experimental follow-up studies implementing animal-assisted therapy in patients with psychotic disorders were included. Pooled standardized mean differences (SMDs) with 95% confidence intervals (CIs) were estimated using a random effects model. Heterogeneity was assessed with the I² statistic. A total of 12 studies (10 randomized controlled trials, a nonrandomized controlled trial and a pre-post study) involving 408 patients (mean age range: 37.0–55.3 years; 32.6% women) were included. Compared with control conditions, patients receiving animal-assisted therapy (predominantly dog-assisted) showed significantly greater pre-post improvements in negative symptoms (SMD = -0.51, 95% CI: -0.95, -0.07; I 2 = 45.1%; n = 6). No significant effects were found for positive symptoms (SMD = -0.68, 95% CI: -1.68, 0.32; I 2 = 83.8%; n = 6) or general symptoms (SMD = -0.08, 95% CI: -0.86, 0.69; I 2 = 72.5%; n = 4). Sensitivity analyses restricted to dog-assisted interventions yielded similar effect estimates. Anxiety symptoms showed reductions but could not be synthesized quantitatively. Animal-assisted therapy may help alleviate symptoms in patients with psychotic disorders, particularly by reducing negative symptoms. Further randomized controlled trials are needed to confirm these findings and clarify their clinical significance. • Dogs were the species most commonly used in animal-assisted therapy • Animal-assisted therapy had a positive effect by reducing negative symptoms in patients with psychotic disorders • Anxiety levels also decreased after animal-assisted therapy
Nuts4Brain-RCT: Protocol for a Three-Arm Randomized Controlled Trial Examining the Dose–Response Effects of Nut Consumption on Mental Health in Young Adults Arthur Eumann Mesas, Fernando Peral-Martínez, Tomás Olivo-Martins-de-Passos, Estela Jiménez-López, Nuria Beneit, Isabel Antonia Martínez-Ortega, Valentina Díaz-Goñi, Sandra Herraiz-Garrote, Irene Martínez-García, David Casanova-Rodríguez, Eva Rodríguez-Gutiérrez, Bruno Bizzozero-Peroni, Ana Ballesta-Castillejos, Shkelzen Cekrezi, Irene Marcilla-Toribio, Sergio Núñez de Arenas-Arroyo, Carlos Álvarez-Herraiz, Carla Soraya Costa Maia, Soraia Pinheiro Machado, Luis Felipe Nunes de Oliveira, Sandra Serrano-Martínez, Vanessa Martínez-Madrid, María Concepción Calderón-Alva, José Francisco López-Gil, Rubén Fernández-Rodríguez, Cristina Cadenas-Sánchez, María Medrano, María Eugenia Visier-Alfonso, Vicente Martínez-Vizcaíno, Miriam Garrido-Miguel Healthcare Switzerland, 2026 Introduction: Mental disorders, particularly depression and anxiety, represent a leading source of morbidity and disability in young adults, a group increasingly exposed to cumulative psychological processes and environmental stressors. Although evidence links healthy dietary patterns with improved mental health symptoms, the specific contribution of nut consumption (rich in anti-inflammatory, antioxidant, and neuroprotective compounds) remains insufficiently examined in this population. Current evidence also lacks robust data on the dose–response effects of nut consumption and mechanistic pathways involving biomarkers relevant to brain function and mental health. The Nuts4Brain-RCT will investigate the impact of a 6-month mixed-nut consumption intervention on mental health symptoms, cognitive functioning, sleep quality, overall well-being, health-related quality of life, and biochemical brain function mediators in young adults. Methods and analysis: A 6-month, randomized, single-blinded, three-arm, dose–response, parallel-group clinical trial will be conducted with 135 university students aged 18–24 years from the University of Castilla-La Mancha, Cuenca, Spain. The participants will be randomly assigned in a 1:1:1 ratio to one of three groups: (1) a control group maintaining their habitual diet while avoiding nut consumption; (2) a 30 g/day mixed-nut consumption group; or (3) a 60 g/day mixed-nut consumption group. The nut consumption intervention will include unsalted, unroasted walnuts, almonds, hazelnuts, and pistachios. The primary outcomes will include depressive (BDI-II) and anxiety (GAD-7) symptoms, perceived stress (PSS-10), cognitive performance (NIH Toolbox), and plasma brain-derived neurotrophic factor (BDNF). Assessments will take place at baseline and at 3 (intermediate), 6 (end of intervention) and 12 months (follow-up). Repeated-measures mixed-effects models will be applied to estimate the effects of nut consumption and dosage on mental health outcomes. Ethics and dissemination: The study adheres to the principles of the Declaration of Helsinki and the Singapore Statement on Research Integrity and obtained approval from the Clinical Research Ethics Committee of the Virgen de la Luz Hospital, Cuenca, Spain (REG: 2025/E0125). The findings will be disseminated through high-impact open-access peer-reviewed publications, presentations at scientific conferences, and social media platforms. Trial registration: ClinicalTrials.gov. Identifier: NCT07292610.
Are Sleep Parameters and Chronotype Associated with Eating Disorder Risk? A Cross-Sectional Study of University Students in Spain Tomás Olivo Martins-de-Passos, Arthur E. Mesas, Nuria Beneit, Valentina Díaz-Goñi, Fernando Peral-Martinez, Shkelzen Cekrezi, Vicente Martinez-Vizcaino, Estela Jimenez-Lopez Journal of Clinical Medicine, 2024 Objectives: Eating disorders (EDs) have emerged as a growing public health concern. However, the role of sleep in this context remains underexplored. The aim of this cross-sectional study was to determine the associations between sleep parameters and chronotype with ED risk in a sample of university students in Spain. Methods: ED risk was assessed via the Sick, Control, One stone, Fat, Food Questionnaire, and sleep quality was assessed via the Pittsburgh Sleep Quality Index. Other sleep parameters and chronotypes were self-reported. Sociodemographic, body composition, lifestyle, and depressive symptom data were collected. Logistic and linear regression models adjusted for the main confounders were used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of the study associations. Results: A total of 403 students (70.2% female) aged 18 to 30 years participated in the study. Those reporting poor sleep quality (OR = 1.85, 95% CI 1.08–3.17, p = 0.025) and ≤6 h of night-time sleep duration (OR = 4.14, 95% CI 2.00–8.57, p < 0.01) were more likely to be at risk of EDs in the adjusted analyses. The association between night-time sleep duration and the risk of ED did not remain significant when we adjusted for sleep quality. In addition, an evening chronotype was associated with an increased risk of EDs (OR = 1.68, 95% CI 1.07–2.66, p = 0.039) only before adjustment for confounders. Conclusions: Among university students, poorer sleep quality was cross-sectionally associated with EDs. Future prospective studies are needed to examine whether promoting sleep quality may serve as an effective strategy for preventing the risk of EDs.
RECENT SCHOLAR PUBLICATIONS
Nuts4Brain-RCT: Protocol for a Three-Arm Randomized Controlled Trial Examining the Dose–Response Effects of Nut Consumption on Mental Health in Young Adults AE Mesas, F Peral-Martínez, T Olivo-Martins-de-Passos, ... Healthcare 14 (4), 435 , 2026 2026
Animal-assisted therapy in patients with psychotic disorders: a systematic review and meta-analysis AM Peraile-Huerta, E Jiménez-López, V Díaz-Goñi, ... Complementary Therapies in Medicine, 103322 , 2026 2026 Citations: 1
Nuts4Brain-RCT: Protocol for a Three-Arm Randomized Controlled Trial Examining the Dose–Response Effects of Nut Consumption on Mental Health in Young Adults A Eumann Mesas, F Peral Martínez, T Olivo Martins de Passos, ... MDPI , 2026 2026
Are sleep parameters and chronotype associated with eating disorder risk? A cross-sectional study of university students in Spain TO Martins-de-Passos, AE Mesas, N Beneit, V Díaz-Goñi, ... Journal of Clinical Medicine 13 (18), 5482 , 2024 2024 Citations: 7
MOST CITED SCHOLAR PUBLICATIONS
Are sleep parameters and chronotype associated with eating disorder risk? A cross-sectional study of university students in Spain TO Martins-de-Passos, AE Mesas, N Beneit, V Díaz-Goñi, ... Journal of Clinical Medicine 13 (18), 5482 , 2024 2024 Citations: 7
Animal-assisted therapy in patients with psychotic disorders: a systematic review and meta-analysis AM Peraile-Huerta, E Jiménez-López, V Díaz-Goñi, ... Complementary Therapies in Medicine, 103322 , 2026 2026 Citations: 1
Nuts4Brain-RCT: Protocol for a Three-Arm Randomized Controlled Trial Examining the Dose–Response Effects of Nut Consumption on Mental Health in Young Adults AE Mesas, F Peral-Martínez, T Olivo-Martins-de-Passos, ... Healthcare 14 (4), 435 , 2026 2026
Nuts4Brain-RCT: Protocol for a Three-Arm Randomized Controlled Trial Examining the Dose–Response Effects of Nut Consumption on Mental Health in Young Adults A Eumann Mesas, F Peral Martínez, T Olivo Martins de Passos, ... MDPI , 2026 2026