The Kynurenine Pathway in Attention-Deficit/Hyperactivity Disorder: A Systematic Review and Meta-Analysis of Blood Concentrations of Tryptophan and Its Catabolites.

Preliminary evidence shows that the kynurenine pathway (KP) may be altered in attention-deficit/hyperactivity disorder (ADHD). We thus conducted a systematic review and meta-analysis exploring the peripheral blood concentrations of tryptophan catabolites (TRYCATs) in people with ADHD. We searched the main electronic databases up to 7th December 2023. Standardised mean differences (SMDs) with 95% confidence intervals (95%CIs) were used to compare TRYCAT concentrations between participants with ADHD and healthy controls (HCs). We included eight studies. Random-effects meta-analyses found higher kynurenine (SMD = 0.56; 95%CI: 0.04 to 1.08; p = 0.033; I2 = 90.3%) and lower kynurenic acid (SMD = -0.33; 95%CI: -0.49 to -0.17; p < 0.001; I2 = 0%) concentrations in people with ADHD compared to HCs. Additional analyses on drug-free children with ADHD showed higher tryptophan (SMD = 0.31; 95%CI: 0.11 to 0.50; p = 0.002; I2 = 0%) and kynurenine (SMD = 0.74; 95%CI: 0.30 to 1.17; p < 0.001; I2 = 76.5%), as well as lower kynurenic acid (SMD = -0.37; 95%CI: -0.59 to -0.15; p < 0.001; I2 = 0%) blood levels, as compared to HCs. Despite some limitations, our work provides preliminary evidence on KP alterations in ADHD that may suggest decreased neuroprotection. Further research is needed to clarify the role of the KP in ADHD.

Blood concentrations of anterior pituitary hormones in drug-naïve people with first-episode psychosis: A systematic review and meta-analysis.

INTRODUCTION: The role of anterior pituitary hormones - i.e., adrenocorticotropic hormone (ACTH), luteinizing and follicle stimulating hormones (LH and FSH), growth hormone (GH), prolactin (PRL), and thyroid-stimulating hormone (TSH) - in early schizophrenia and psychoses unclear. We thus performed a systematic review and meta-analysis on the blood concentrations of ACTH, LH and FSH, GH, PRL, and TSH in drug-naïve people with first-episode psychosis (FEP) as compared with healthy controls. METHODS: We searched Embase, MEDLINE, and PsycInfo for articles indexed until September 2022. Data quality was appraised. Random-effects meta-analyses were carried out, generating pooled standardized mean differences (SMDs). Between-study heterogeneity was estimated using the I2 statistic. Sensitivity and meta-regression analyses were performed. RESULTS: Twenty-six studies were included. Drug-naïve people with FEP, compared to healthy subjects, had higher blood concentrations of ACTH (k = 7; N = 548; SMD = 0.62; 95%CI: 0.29 to 0.94; p < 0.001; I2 = 60.9%) and PRL (k = 17; N = 1757; SMD = 0.85; 95%CI: 0.56 to 1.14; p < 0.001; I2 = 85.5%) as well as lower levels of TSH (k = 6; N = 677; SMD = -0.34; 95%CI: -0.54 to -0.14; p = 0.001; I2 = 29.1%). Meta-regressions did not show any moderating effect of age (p = 0.78), sex (p = 0.21), or symptom severity (p = 0.87) on PRL concentrations in drug-naïve FEP. Available data were not sufficient to perform meta-analyses on FSH, LH, and GH. CONCLUSIONS: Drug-naïve people with FEP have altered ACTH, PRL, and TSH blood concentrations, supporting the hypothesis that an abnormal anterior pituitary hormone secretion may be involved in the onset of schizophrenia and psychoses. Further research is needed to elucidate the role of pituitary hormones in FEP.

The role of BDNF in major depressive disorder, related clinical features, and antidepressant treatment: Insight from meta-analyses.

The brain-derived neurotrophic factor (BDNF) has received considerable attention as a potential biomarker of major depressive disorder (MDD) and antidepressant response. We conducted an overview of meta-analyses investigating the relationship of BDNF with MDD, related clinical features, and antidepressant treatment. Based on a systematic screening on main electronic databases, 11 systematic reviews with meta-analyses were included. Available evidence suggests that people with MDD have peripheral and central BDNF levels lower than non-depressed individuals. A negative correlation between blood BDNF and symptom severity emerged, while no association with suicidality was detected. Moreover, an increase in blood BDNF levels after antidepressant treatment, proportional to symptom improvement, was reported. BDNF levels seem to be increased in both treatment responders and remitters, remaining stable in non-responders. Conversely, no variations of BDNF concentrations after non-pharmacological interventions (electroconvulsive therapy, repetitive transcranial magnetic stimulation, and physical activity) were found. The findings of this overview appear consistent with the neurotrophic hypothesis of depression, suggesting that BDNF may play a role in both MDD pathophysiology and pharmacological treatment response.

Long-acting injectable antipsychotics for the treatment of bipolar disorder: evidence from mirror-image studies.

Clinical trials and real-world data have shown that long-acting injectable antipsychotics (LAIs) might be an effective therapeutic option also for people with bipolar disorder (BD). However, complementing evidence from mirror-image studies investigating LAIs in BD is scattered and has not been systematically evaluated so far. We thus performed a review of observational mirror-image studies testing the effectiveness of LAI treatment on clinical outcomes in people with BD. Embase, MEDLINE, and PsycInfo electronic databases were systematically searched (via Ovid) up to November 2022. We included six mirror-image studies that compared relevant clinical outcomes between the 12-months after (post-treatment period) and the 12-months before (pre-treatment period) the initiation of a LAI treatment in adults with BD. We found that LAI treatment is associated with a significant reduction in days spent in hospital and number of hospitalizations. Moreover, LAI treatment seems to be associated with a significant decrease in the proportion of individuals with at least one hospital admission, even though data on this outcome were reported by just two studies. In addition, studies consistently estimated a significant reduction of hypo-/manic relapses after LAI treatment initiation, while the effect of LAIs for depressive episodes is less clear. Finally, LAI treatment initiation was associated with a lower number of emergency department visits in the year after LAI initiation. The findings of this review seem to suggest that the use of LAIs is an effective strategy to improve major clinical outcomes in people with BD. Nonetheless, additional research, based on standardized assessments of prevalent polarity and relapses, is needed to identify the clinical characteristics of individuals with BD who are most likely to benefit from a LAI treatment.

Clinical correlates of comorbid attention deficit hyperactivity disorder in adults suffering from bipolar disorder: A meta-analysis.

OBJECTIVE: Attention deficit hyperactivity disorder is a frequent comorbid condition in adults with bipolar disorder. We performed a meta-analysis aimed at assessing sociodemographic and clinical correlates of attention deficit hyperactivity disorder in bipolar disorder. METHOD: We searched main electronic databases up to June 2021. Random-effects meta-analyses, with relevant meta-regression and quality-based sensitivity analyses, were carried out to estimate the association between attention deficit hyperactivity disorder and putative correlates, grading the quality of evidence. RESULTS: We included 43 studies, based on 38 independent samples. Attention deficit hyperactivity disorder participants were more likely to be males (odds ratio = 1.46; p < 0.001) and unemployed (odds ratio = 1.45; p = 0.045), and less likely to be married (odds ratio = 0.62; p = 0.014). They had an earlier onset of bipolar disorder (standardized mean difference = -0.36; p < 0.001); more mood episodes (standardized mean difference = 0.35; p = 0.007), particularly depressive (standardized mean difference = 0.30; p = 0.011) and mixed (standardized mean difference = 0.30; p = 0.031) ones; higher odds of using antidepressants (odds ratio = 1.80; p = 0.024) and attempted suicides (odds ratio = 1.83; p < 0.001) and lower odds of psychotic features (odds ratio = 0.63; p = 0.010). Moreover, they were more likely to have generalized anxiety disorder (odds ratio = 1.50; p = 0.019), panic disorder (odds ratio = 1.89; p < 0.001), social phobia (odds ratio = 1.61; p = 0.017), eating disorders (odds ratio = 1.91; p = 0.007), antisocial personality disorder (odds ratio = 3.59; p = 0.004) and substance (odds ratio = 2.29; p < 0.001) or alcohol (odds ratio = 2.28; p < 0.001) use disorders. Quality of the evidence was generally low or very low for the majority of correlates, except for bipolar disorder onset and alcohol/substance use disorders (high), and suicide attempts (moderate). CONCLUSION: Comorbid bipolar disorder/attention deficit hyperactivity disorder may have some distinctive clinical features including an earlier onset of bipolar disorder and higher comorbid alcohol/substance use disorder rates. Further research is needed to identify additional clinical characteristics of this comorbidity.

Blood concentrations of neopterin and biopterin in subjects with depression: A systematic review and meta-analysis.

INTRODUCTION: Pteridines, such as neopterin, biopterin, and tetrahydrobiopterin (BH4), may be involved in depression pathophysiology owing to their links to immune-inflammatory response, oxidative and nitrosative stress, and monoaminergic transmission. Nonetheless, studies assessing pteridines in depression are inconsistent. We conducted a systematic review and meta-analysis of observational studies comparing blood pteridine concentrations between subjects with depression and healthy controls (HCs). METHODS: We searched Embase, MEDLINE, and PsycInfo for articles indexed through November 2021. Study quality was appraised, evaluating age and gender comparability between groups, sample representativeness, and methods to assess depression. Random-effects meta-analyses were carried out, generating pooled standardized mean differences (SMDs). Heterogeneity across studies was estimated using the I2 statistic. RESULTS: Twenty-four studies, involving 3075 subjects, were included. Individuals with depression showed blood neopterin concentrations higher than HCs (k = 19; SMD = 0.36; p < 0.001) with moderate heterogeneity across studies (I2 = 58.2%). No moderating role of age, gender, or type of blood sample was found. Sensitivity analyses showed no impact of inconsistency and quality of studies on findings. Neopterin concentrations were higher among individuals with major depressive disorder compared to HCs (SMD = 0.44; p < 0.001). This held true also when considering only drug-free subjects (SMD = 0.68; p = 0.003). No differences in biopterin concentrations were found between subjects with depression and HCs (k = 5; SMD = -0.35; p = 0.086), though this result was limited by inconsistency of findings (I2 = 77.9%) and quality of studies. Finally, no sufficient data were available for a meta-analysis on BH4. CONCLUSIONS: As a whole, our work partly supports the hypothesis of an imbalance of pteridine metabolism in depression.

Effect of long-acting injectable antipsychotics on 1-year hospitalization in bipolar disorder: a mirror-image study.

Long-acting injectable (LAI) antipsychotics are often used for the long-term management also of bipolar disorder (BD). Nonetheless, evidence on their effect on pragmatic outcomes such as hospitalization risk in BD is inconsistent. We carried out a mirror-image study comparing rates and number of days of hospitalization, one year before and after the initiation of LAI treatment, in a sample of subjects with BD. Participants were selected from the STAR Network Depot Study, a pragmatic, observational, multicenter research involving a cohort of inpatients and outpatients consecutively started on LAI treatment. Variations in rates and in total number of days of hospitalization between the 12 months before and those after treatment initiation were analyzed. Among 461 individuals screened for eligibility, we included 71 adults with BD, initiated either on first- (FGA) or second-generation (SGA) LAIs. We found a significant decrease in terms of 12-month hospitalization rates (p < 0.001) and number of days (p < 0.001) after LAI initiation, without any effect by age, gender, alcohol/substance use disorders, and symptom severity. Subgroup analyses based on antipsychotic class, history of LAI treatment, and concomitant oral medications, confirmed the decreasing trend on both hospitalization rates and number of days. However, these reductions were not significant among participants who continued this treatment for less than 6 months. Comprehensively, this study supports the role of LAIs as effective maintenance treatment options for BD. Further research is needed to identify clinical characteristics of people with BD who would most benefit from long-acting formulations of antipsychotics.

Digital mental health interventions for anxiety and depressive symptoms in university students during the COVID-19 pandemic: A systematic review of randomized controlled trials.

University students are particularly vulnerable to mental health issues, with anxiety and depression identified as the most common conditions. During the COVID-19 pandemic, social distancing, self-isolation, and difficulties linked to online teaching and learning have increased their burden of anxiety and depressive symptoms. Thus, the urgent need to intervene in favour of these vulnerable subjects, together with the difficulties in delivering in-person interventions because of lockdowns and restrictions, has led to prioritize digital mental health strategies. This study aimed at systematically reviewing the existing literature on digital mental health interventions targeting anxiety and depressive symptoms in university students during the COVID-19 emergency. Systematic searches of Medline, Embase, and PsycInfo databases identified eight randomized controlled trials. Regarding anxiety symptoms, digitally delivered cognitive behavioural therapy, dialectical behaviour therapy, and mind-body practice techniques emerged as valid strategies, while digital positive psychology and mindfulness-based interventions showed mixed results. On the other hand, digitally delivered dialectical behaviour therapy and positive psychology interventions have shown some efficacy in reducing depressive symptoms. Overall, the available literature, albeit of low quality, seems to support the role of digital interventions in promoting the mental health of university students during the COVID-19 pandemic.

Los estudiantes universitarios son particularmente vulnerables a los problemas de salud mental, siendo la ansiedad y la depresión las condiciones más comunes. Durante la pandemia de COVID-19, el distanciamiento social, el autoaislamiento y las dificultades relacionadas con la enseñanza y el aprendizaje en línea han aumentado su carga de ansiedad y síntomas depresivos. Así, la urgente necesidad de intervenir a favor de estos sujetos vulnerables, junto con las dificultades para realizar intervenciones presenciales a causa de los confinamientos y restricciones, ha llevado a priorizar estrategias de salud mental digital. Este estudio tuvo como objetivo revisar sistemáticamente la literatura existente sobre intervenciones digitales de salud mental dirigidas a la ansiedad y los síntomas depresivos en estudiantes universitarios durante la emergencia de COVID-19. Las búsquedas sistemáticas en las bases de datos Medline, Embase y PsycInfo identificaron ocho ensayos controlados aleatorios. Con respecto a los síntomas de ansiedad, la terapia cognitiva conductual, la terapia conductual dialéctica y las técnicas de práctica mente-cuerpo entregadas digitalmente surgieron como estrategias válidas, mientras que la psicología positiva digital y las intervenciones basadas en el mindfulness mostraron resultados mixtos. Por otro lado, la terapia conductual dialéctica y las intervenciones de psicología positiva proporcionadas digitalmente han demostrado cierta eficacia en la reducción de los síntomas depresivos. En general, la literatura disponible, aunque de baja calidad, parece respaldar el papel de las intervenciones digitales en la promoción de la salud mental de los estudiantes universitarios durante la pandemia de COVID-19.

The association of kynurenine pathway metabolites with symptom severity and clinical features of bipolar disorder: An overview.

BACKGROUND: The balance between neurotoxic and neuroprotective effects of kynurenine pathway (KP) components has been recently proposed as a key element in the pathophysiology of bipolar disorder (BD) and related mood episodes. This comprehensive overview explored the link of KP with symptom severity and other clinical features of BD. METHODS: We searched Medline, Embase, and PsycInfo electronic databases for studies assessing the association of peripheral and/or central concentrations of KP metabolites with putative clinical features, including symptom severity and other clinical domains in BD. RESULTS: We included the findings of 13 observational studies investigating the possible variations of KP metabolites according to symptom severity, psychotic features, suicidal behaviors, and sleep disturbances in BD. Studies testing the relationship between KP metabolites and depression severity generated mixed and inconsistent findings. No statistically significant correlations with manic symptoms were found. Moreover, heterogeneous variations of the KP across different clinical domains were shown. Few available studies found (a) higher levels of cerebrospinal fluid kynurenic acid and lower of plasma quinolinic acid in BD with psychotic features, (b) lower central and peripheral picolinic acid levels in BD with suicide attempts, and (c) no significant correlations between KP metabolites and BD-related sleep disturbances. CONCLUSIONS: An imbalance of KP metabolism toward the neurotoxic branches is likely to occur in people with BD, though evidence on variations according to specific clinical features of BD is less clear. Additional research is needed to clarify the role of KP in the etiopathogenesis of BD and related clinical features.

Comparing 1-year effectiveness and acceptability of once-monthly paliperidone palmitate and aripiprazole monohydrate for schizophrenia spectrum disorders: Findings from the STAR Network Depot Study.

In this prospective study, we assessed the effectiveness and acceptability of paliperidone palmitate 1-month (PP1M) and aripiprazole monohydrate (AM) over 1-year follow-up. We included 195 subjects (117 treated with PP1M and 78 with AM) with schizophrenia spectrum disorders from real-world settings. We estimated no differences in hospitalization (Odds Ratio=1.59; p = 0.12), symptoms improvement (p = 0.90 adjusted for baseline severity), and discontinuation (Hazard Ratio=0.72; p = 0.20) at study endpoint. Although current evidence suggests the possible superiority of AM over PP1M, our findings showed comparable effectiveness between these drugs. Additional studies in real-world settings with direct comparisons between these two LAIs are needed.

Practical Guidance for the Use of Long-Acting Injectable Antipsychotics in the Treatment of Schizophrenia.

Schizophrenia is a severe mental illness causing a high degree of disability. First- and second-generation antipsychotics (FGAs and SGAs) represent key resources for its acute and long-term management. Since a poor adherence to oral treatments may negatively impact the course of the disorder, long-acting injectable antipsychotics (LAIs) are often used to reduce clinical relapses. Notwithstanding their potential beneficial features, LAIs use in clinical practice remains somewhat hampered by the limited amount of relevant systematic information. This review thus aims at providing a clinical, practical guidance for the use of LAIs in the treatment of schizophrenia. We synthetized main information on indications, dosage, and administration of LAIs approved by the US Food and Drug Administration (FDA) and/or in EU countries, as well as evidence from the most recent systematic reviews and meta-analyses. Currently available information, though heterogeneous, shows that LAIs can prevent relapses and rehospitalizations, improving clinical outcomes and favouring sustained remission among people with schizophrenia. The use of SGA LAIs is supported by more robust evidence than FGA LAIs. Along with their positive impact on the prevention of treatment discontinuation, some LAIs might also enhance individual global functioning and quality of life, without additional adverse events or health-care costs, as compared with oral antipsychotics. Although which LAIs can be considered a first-choice option, as well as their superiority over oral antipsychotics, remain unclear issues, this review offers a comprehensive overview of information available on the use of LAIs for people with schizophrenia, providing clinicians with practical guidance in terms of efficacy and acceptability of single agents. Literature gaps and future research needs are also described.

Some of us are most at risk: Systematic review and meta-analysis of correlates of depressive symptoms among healthcare workers during the SARS-CoV-2 outbreak.

The COVID-19 pandemic has had a severe psychosocial impact on healthcare workers (HCWs). This systematic review and meta-analysis aimed at evaluating the association between individual features and depressive symptoms reported by HCWs during the pandemic. We searched Medline, Embase, and PsycInfo up to 23 June 2020. We included cross-sectional studies testing the association between individual correlates and depressive symptoms in HCWs during the SARS-CoV-2 outbreak. Fourteen studies met inclusion criteria, involving 14,173 HCWs (3,070 with depressive symptoms). Women (OR = 1.50; 95 %CI: 1.28-1.76; I2 = 40.0 %), individuals with suspected/confirmed COVID-19 (OR = 2.10; 95 %CI: 1.64-2.69; I2 = 0 %), and those with an infected family member or friend (OR = 1.67; 95 %CI: 1.37-2.04; I2 = 0%) were more likely to report depressive features, which, instead, were less frequent among doctors (compared with nurses) (OR = 0.80; 95 %CI: 0.66-0.98; I2 = 48.2 %) and HCWs who felt adequately protected (OR = 0.48; 95 %CI: 0.32-0.72; I2 = 36.3 %). Our study provided timely evidence on the correlates of depressive symptoms among HCWs during the pandemic. Early screening is crucial to develop tailored health interventions, redesigning the response to COVID-19.

Repurposed drugs as adjunctive treatments for mania and bipolar depression: A meta-review and critical appraisal of meta-analyses of randomized placebo-controlled trials.

Several drugs previously tested in clinical trials and approved for different indications have been repurposed for bipolar disorder. We carried out a systematic meta-review of meta-analyses of randomized placebo-controlled trials investigating repurposed drugs as adjunctive treatments for mania and bipolar depression. We performed a critical appraisal using 'A MeaSurement Tool to Assess systematic Reviews' Version 2 (AMSTAR 2). We synthesized results on efficacy, tolerability, and safety, assessing evidence quality according to the 'Grading of Recommendations, Assessment, Development and Evaluations' (GRADE) approach. Our systematic search identified nine eligible studies investigating 12 drugs, four for mania and eight for bipolar depression. The quality of reporting was heterogeneous according to AMSTAR 2. In mania, allopurinol (for symptoms reduction and remission at 4-8 weeks) and tamoxifen (for response and symptoms reduction at 4-6 weeks) showed higher efficacy than placebo, with low and very low quality of evidence, respectively. Concerning bipolar depression, modafinil/armodafinil (for response, remission, and symptoms reduction at 6-8 weeks) and pramipexole (for response and symptoms reduction at 6 weeks) were superior to placebo, despite the low quality of evidence. Results on the efficacy of celecoxib and N-acetylcysteine were of low quality and limited to certain outcomes. Overall, the lack of evidence of high and moderate quality does not allow us to draw firm conclusions on the clinical utility of repurposed drugs as adjunctive treatments for mania and bipolar depression, highlighting the need for additional research.

Thyroid hormones in persons with schizophrenia: A systematic review and meta-analysis.

There is accumulating evidence that individuals with schizophrenia show altered levels of thyroid hormones. However, a qualitative and quantitative synthesis of findings in this field has not been performed so far. Therefore, we aimed to perform a systematic review and meta-analysis of studies investigating the levels of thyroid-stimulating hormone (TSH), free thyroxine (fT4), total thyroxine (tT4), free triiodothyronine (fT3) and total triiodothyronine (tT3) in multiple-episode schizophrenia (MES) and first-episode psychosis (FEP). Electronic databases were searched from their inception until 30th May 2020 by two independent reviewers. Random-effects meta-analyses and meta-regression analyses were performed. Altogether, 19 studies were included. Persons with FEP had significantly lower TSH levels (5 studies, g = -0.26, 95%CI: -0.47 to -0.06, p = 0.013, I2 = 21.3%), higher fT4 levels (3 studies, g = 0.58, 95%CI: 0.15-1.01, p = 0.008, I2 = 64.6%) and lower tT3 levels (2 studies, g = -0.60, 95%CI: -0.82 to -0.37, p < 0.001, I2 = 0%) compared to controls. Elevated TSH levels were found in persons with MES (13 studies, g = 0.20, 95%CI: 0.02-0.39, p = 0.031, I2 = 50.0%). Our findings imply that the levels of TSH might be decreased in persons with FEP and increased in those with MES. Other alterations need to be confirmed by additional studies. These findings imply the need to monitor the levels of TSH and thyroid hormones from the onset of psychosis.

The kynurenine pathway in bipolar disorder: a meta-analysis on the peripheral blood levels of tryptophan and related metabolites.

Growing evidence suggests that a dysregulation of the kynurenine pathway (KP) occurs in bipolar disorder (BD). This systematic review and meta-analysis aimed at assessing the possible differences in peripheral blood levels of KP metabolites between individuals with BD and healthy controls. We searched Medline, Embase, and PsycInfo electronic databases for articles indexed up to February 2020. We included any observational study comparing the peripheral blood levels of at least one KP metabolite between adults with BD and healthy controls. Random-effects meta-analyses were carried out generating pooled standardized mean differences (SMDs). Heterogeneity between studies was estimated using the I2 index. Meta-regression and sensitivity analyses were conducted. Sixteen studies met inclusion criteria and were included in our study. Meta-analyses showed that individuals with BD have lower peripheral blood levels of tryptophan (SMD = -0.29), kynurenine (SMD = -0.28), kynurenic acid (SMD = -0.30), and xanthurenic acid (SMD = -0.55), along with lower kynurenic acid to kynurenine (SMD = -0.60) and kynurenic acid to quinolinic acid (SMD = -0.37) ratios, than healthy controls. Individuals with a manic episode showed the greatest reductions in tryptophan levels (SMD = -0.51), whereas kynurenic acid levels were more reduced among subjects in a depressive phase (SMD = -0.70). Meta-regression and sensitivity analyses confirmed our results. The findings of the present meta-analysis support the hypothesis of an abnormality of the KP in BD. Considering the partial inconsistency of the findings and the small-to-medium magnitude of the estimated effect sizes, additional research assessing possible mediators or confounders is needed.

Pre-Discharge Predictors of 1-Year Rehospitalization in Adolescents and Young Adults with Severe Mental Disorders: A Retrospective Cohort Study.

Background and objectives: Readmissions of youths hospitalized for a severe mental disorder are common events and bear a remarkable human, social, and economic burden. The current study aimed at evaluating predictors of 1-year rehospitalization in a sample of adolescents and young adults with severe mental disorders. Materials and Methods: Data for ≤25-year-old inpatients with a severe mental disorder and consecutively admitted between 1 January 2016 and 30 June 2019 were collected. Subjects were retrospectively assessed over a follow-up period of one year after the index discharge to track readmissions-i.e., the primary outcome variable. Standard descriptive statistics were used. The association between variables and 1-year rehospitalization was estimated using the univariate Cox proportional hazards regression model. We then carried out a multivariable Cox regression model, also estimating the covariate-adjusted survivor function. Hazard ratios (HRs) with related 95% confidence intervals (95% CIs) were provided. Results: The final sample included 125 individuals. The multivariable Cox regression model estimated that co-occurring substance use disorders (HR = 2.14; 95% CI: 1.08 to 4.26; p = 0.029) and being admitted for a suicide attempt (HR = 2.49; 95% CI: 1.13 to 5.49; p = 0.024) were both significant predictors of 1-year rehospitalization. Conclusions: Our study showed that comorbid substance use disorders and being admitted for a suicide attempt were predictors of early readmission in youths with severe mental disorders. Although their generalizability is limited, our findings could contribute to improve the quality of young patients' mental health care by identifying vulnerable subjects who may benefit from tailored interventions to prevent rehospitalizations.