Self-harm, suicidal ideation, and the positive symptoms of psychosis: Cross-sectional and prospective data from a national household survey

Machine learning and the prediction of suicide in psychiatric populations: a systematic review

Machine learning (ML) has emerged as a promising tool to enhance suicidal prediction. However, as many large-sample studies mixed psychiatric and non-psychiatric populations, a formal psychiatric diagnosis emerged as a strong predictor of suicidal risk, overshadowing more subtle risk factors specific to distinct populations. To overcome this limitation, we conducted a systematic review of ML studies evaluating suicidal behaviors exclusively in psychiatric clinical populations. A systematic literature search was performed from inception through November 17, 2022 on PubMed, EMBASE, and Scopus following the PRISMA guidelines. Original research using ML techniques to assess the risk of suicide or predict suicide attempts in the psychiatric population were included. An assessment for bias risk was performed using the transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) guidelines. About 1032 studies were retrieved, and 81 satisfied the inclusion criteria and were included for qualitative synthesis. Clinical and demographic features were the most frequently employed and random forest, support vector machine, and convolutional neural network performed better in terms of accuracy than other algorithms when directly compared. Despite heterogeneity in procedures, most studies reported an accuracy of 70% or greater based on features such as previous attempts, severity of the disorder, and pharmacological treatments. Although the evidence reported is promising, ML algorithms for suicidal prediction still present limitations, including the lack of neurobiological and imaging data and the lack of external validation samples. Overcoming these issues may lead to the development of models to adopt in clinical practice. Further research is warranted to boost a field that holds the potential to critically impact suicide mortality.

Mediating role of anxiety and impulsivity in the association between child maltreatment and lifetime non-suicidal self-injury with and without suicidal self-injury

BACKGROUND

Child maltreatment can increase the risk of lifetime non-suicidal self-injury (NSSI) and suicidal self-injury (SSI), but there is limited knowledge regarding the differences of potentially psychological mechanisms between NSSI with and without SSI.

METHODS

Participants, 3918 community-based Chinese young men aged 18-34 years in Chengdu, were included in this study. We investigated the association between depression, anxiety, psychosis, child maltreatment, adulthood traumatic events, impulsivity, alcohol dependence, drug abuse, and lifetime of NSSI among participants with and without SSI. Parallel mediation analysis was utilized to explore the mediators for the relation between child maltreatment and NSSI.

RESULTS

The prevalence of lifetime NSSI was 6.1 % (95 % CI: 5.4 %-6.9 %) among young men. Anxiety and impulsivity partially mediated the effect of child maltreatment on NSSI either with (indirect effect: 51.2 %) or without SSI (indirect effect: 34.3 %). Depression was independently and significantly associated with only NSSI but not with NSSI+SSI. Alcohol dependence and psychosis were independently and significantly associated with NSSI+SSI and mediated the effect of child maltreatment on NSSI+SSI.

LIMITATIONS

The cross-sectional survey data limits the robustness of the proof to the causal relationships.

CONCLUSIONS

Anxiety and impulsivity are associated with NSSI either with or without SSI and partially mediate the effect of child maltreatment on NSSI. Depression is associated with only NSSI, while alcohol dependence and psychosis are only associated with NSSI+SSI. It could be crucial to improve treatment and recovery of alcohol dependence and psychosis for preventing young men engaged in NSSI from attempting SSI.

Risk factors for suicidality across psychosis vulnerability spectrum

BACKGROUND

Suicide is a leading cause of death in individuals with psychotic disorders. Risk factors for suicidality across the psychosis vulnerability spectrum are insufficiently known.

METHODS

For patients (n = 830), siblings (n = 664) and controls (n = 444), suicidality was assessed by the use of a clinical interview. Multilevel modelling was used to investigate risk factors of suicidality. Lastly, risk factor × familial risk interaction effects were examined.

RESULTS

Multivariable models revealed a significant relation between suicidality and depressive symptoms across all three groups, and childhood trauma in patients and siblings. The association between suicidality and psychotic-like experiences is more pronounced in siblings compared to controls.

CONCLUSION

Across the psychosis vulnerability spectrum, depressive symptoms and childhood trauma have been associated with suicidality. Clinicians should pay attention to suicidality in individuals at high familial risk for psychosis with psychotic-like experiences.

Strengthening associations between psychotic like experiences and suicidal ideation and behavior across middle childhood and early adolescence

BACKGROUND

Understanding risk factors related to suicidal ideation (SI) and suicidal behaviors (SB) in youth is important for informing prevention and intervention efforts. While it appears that psychotic-like experiences (PLEs) are strongly associated with both SI and SB at different points across the lifespan, the longitudinal nature of this relationship in middle childhood and early adolescence is understudied.

METHODS

The study used the unique longitudinal Adolescent Brain Cognitive Development Study data. Mixed effects linear models examined associations between PLEs and SI and SB over time using three time points of data from ages 9-13.

RESULTS

First, analyses indicated that endorsement of SI and SB increased as youth grew older for those with increased distressing PLEs. Analyses found evidence of bidirectional relationships between PLEs with SI and SB, with evidence that PLEs at baseline were associated with worsening SI and SB over time, including a transition from SI to SB (β = 0.032, FDRp = 0.002). Exploratory analyses showed consistent evidence for strengthened associations over time for higher delusional ideation with both SI and SB (βs > 0.04, FDRps < 0.001), and for perceptual distortions with SB (βs = 0.046, FDRp < 0.001). When accounting for general psychopathology, for SB, the strengthened associations over time was significantly stronger for PLEs (β = 0.053, FDRp < 0.001) compared to general psychopathology (β = 0.022, FDRp = 0.01).

CONCLUSIONS

The present study indicates both SI and SB show strengthened associations with PLEs over time, and that baseline PLEs may predict worsening of suicidality over time. The findings are important clarifications about the nature of the associations between youth-reported PLEs and suicidality over time.

Suicidal ideation in Chinese patients with chronic schizophrenia: prevalence, clinical correlates, and relationship with alexithymia

Suicidal ideation (SI) is common among people with schizophrenia. However, it has received less attention than suicide attempts (SA), especially in the Chinese population. Alexithymia is a well-established risk factor for SI across different populations. Nevertheless, very few studies evaluated their relationship in schizophrenia patients. We aimed to determine the prevalence and clinical correlates of SI and its relationship with alexithymia in 812 Chinese chronic schizophrenia inpatients. We assessed SI, clinical symptoms, and alexithymia by the Beck Scale for Suicidal Ideation, the Positive and Negative Syndrome Scale (PANSS), and the Toronto Alexithymia Scale, respectively. A multiple logistic regression model was conducted to identify independent correlates of SI. Receiver operating characteristic (ROC) curves and area under the curve (AUC) were performed to determine the ability of our model to distinguish between patients with and without SI. 10% (n = 84) reported current SI. Lifetime SA (OR, 4.68; 95% CI 2.76-7.94, p < 0.001), PANSS depressive factor (OR, 1.24; 95% CI 1.12-1.38, p < 0.001), PANSS positive subscale (OR, 1.055; 95% CI 1.004-1.108, p = 0.035), and difficulty identifying emotions (OR, 1.07; 95% CI 1.03-1.12, p = 0.002) were associated with SI. The AUC value was 0.80, indicating excellent distinguishing capabilities. Timely assessments of these factors may help identify schizophrenia patients who are at risk for SI.

Metabolic parameters and thyroid hormones in relation to suicide attempts in patients with first-episode and drug-naive major depressive disorder with comorbid glucose disturbances: a large cross-sectional study

The factors associated with suicide attempts in major depressive disorder (MDD) patients with comorbid glucose disturbances remain unclear. To the best of our knowledge, this is the first study with a large sample size to examine risk factors of suicide attempts in first-episode drug-naïve (FEDN) MDD patients with comorbid glucose disturbances, including clinically relevant factors, metabolic parameters, and thyroid hormone levels. A total of 1718 FEDN MDD patients were enrolled. The Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and Positive and Negative Syndrome Scale (PANSS) were used to assess the clinical symptoms of patients. Fasting blood glucose, metabolic parameters, and thyroid hormone levels were measured. After controlling for HAMA and HAMD scores, the suicide attempt rate was 1.88 times higher in MDD patients with glucose disturbances than in MDD patients without glucose disturbances. Compared to non-suicide attempters, suicide attempters among the MDD patients with glucose disturbances had higher scores on HAMD and HAMA, PANSS positive symptoms, as well as higher levels of systolic and diastolic blood pressure, TC, LDL-C, thyroid stimulating hormone (TSH), TgAb, and thyroid peroxidases antibody (TPOAb). The combination of positive symptom score, HDL-C, systolic blood pressure, and marital status distinguished suicide attempters from non-suicide attempters. In addition, HAMA score, HAMD score, and TPOAb were associated with the number of suicide attempts in MDD patients with comorbid glucose disturbances. Our results suggest a high incidence of suicide attempts in MDD patients with comorbid glucose disturbances. Several clinically relevant factors, metabolic parameters, and thyroid hormone function have an impact on suicide attempts in MDD patients with comorbid glucose disturbances.