Childhood maltreatment is a well-established transdiagnostic risk factor for suicidal ideation; however, previous studies on their association in schizophrenia have produced highly varied results. Moreover, the mechanism linking childhood maltreatment and suicide ideation remains unclear in schizophrenia.

This cross-sectional study aimed to investigate the association between childhood maltreatment and suicide ideation in people with schizophrenia and tested whether insomnia mediated this relationship.

Positive and Negative Syndrome Scale (PANSS), Insomnia Severity Index (ISI), Childhood Trauma Questionnaire – Short Form and Beck Suicidal Ideation Inventory were employed. Logistic regression and mediation analysis were performed.

(a) The prevalence of suicide ideation, insomnia, sexual abuse, emotional neglect, emotional abuse, physical abuse and physical neglect was 10% (n = 61), 18% (n = 111), 11% (n = 68), 25% (n = 153), 6.3% (n = 39), 17% (n = 106) and 39% (n = 239), respectively. In all, 52% (n = 320) reported childhood maltreatment; (b) patients with suicide ideation demonstrated higher insomnia and childhood maltreatment. PANSS depression factor, ISI, lifetime suicidal attempts and emotional abuse were independently associated with suicide ideation; (c) insomnia partially mediated the effects of emotional abuse and emotional neglect on suicide ideation, and insomnia completely mediated the effects of physical neglect and physical abuse on suicide ideation.

Our study calls for formal assessments for childhood maltreatment and insomnia in schizophrenia, which might help identify suicide ideation early. In addition, interventions targeting insomnia might help reduce suicide ideation among people with schizophrenia who experience childhood maltreatment.

Problematic internet use, especially in people with substance use disorder, may negatively affect their quality of life (QoL). However, it is unclear whether sleep quality is a key mediator in the association between problematic internet use and QoL among people with substance use disorder.

This study aimed to investigate the relationship between problematic internet use and QoL and how sleep quality may mediate the association between these two variables.

Overall, 319 people (85% male) with substance use disorder (mean age 42.2 years, s.d. 8.9) participated in a cross-sectional study in Taiwan. The Smartphone Application-Based Addiction Scale, Bergan Social Media Addiction Scale, Internet Gaming Disorder-Short Form, Pittsburgh Sleep Quality Index and World Health Organization Quality of Life Questionnaire Brief Version were used.

The prevalence of sleep problems was 56%. There were significant and direct associations between sleep quality and two types of problematic internet use, and between sleep quality and different dimensions of QoL. All types of problematic internet use were significantly and negatively correlated with QoL. Mediated effects of sleep quality in relationships between the different types of problematic internet use and all dimensions of QoL were significant, except for problematic use of social media.

Different types of problematic internet use in people with substance use disorder may be directly associated with reduced QoL. Sleep quality as a significant mediator in this association may be an underlying mechanism to explain pathways between problematic internet use and QoL in this population.

Amnestic mild cognitive impairment (aMCI) is characterized by delayed P300 latency and reduced grey matter (GM) volume, respectively. The relationship between the features in aMCI is unclear. This study was to investigate the relationship between the altered P300 latency and the GM volume in aMCI.

Thirty-four aMCI and 34 well-matched normal controls (NC) were studied using electroencephalogram during a visual oddball task and scanned with MRI. Both tests were finished in the same day.

As compared with the NC group, the aMCI group exhibited delayed P300 latency in parietal cortex and reduced GM volumes in bilateral temporal pole and left hippocampus/parahippocampal gyrus. A remarkable negative correlation was found between delayed P300 latency and reduced left hippocampal volume only in the aMCI group. Interestingly, the mediating analysis found P300 latency significantly mediated the association between right supramarginal gyrus volume and information processing speed indicated by Stroop Color and Word Test A scores.

The association between delayed P300 latency and reduced left hippocampal volume in aMCI subjects suggests that reduced left hippocampal volume may be the potential structural basis of delayed P300 latency.

Socio-economic status (SES) has been positively associated with physical activity (PA) levels in adolescents. In order to tackle these social inequalities, information is needed about the underlying mechanisms of this association. The present study aimed to investigate the potential mediating role of psychosocial correlates of PA on the relationship between SES and PA in European adolescents.

Cross-sectional study testing the mediating role of psychosocial correlates in the SES–PA association using the product-of-coefficients test of MacKinnon.

Ten European cities in nine different countries, the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study.

Adolescents (n 2780) aged 12·5–17·49 years self-reported on PA (moderate-to-vigorous intensity PA and total PA), SES indicators (education of the mother and Family Affluence Scale) and psychosocial correlates of PA (stage of change, attitudes, awareness, modelling, social support, self-efficacy, benefits, barriers and environmental correlates).

SES (Family Affluence Scale) was significantly associated with moderate-to-vigorous intensity PA. According to single-mediator models, this association was significantly mediated by stage of change (t = 3·6, P ≤ 0·001), awareness (t = 2·7, 0·001 < P ≤ 0·01), modelling (t = 4·8, P ≤ 0·001), self-efficacy (t = 2·5, 0·01<P ≤ 0·05), barriers (t = 2·7, 0·001 < P ≤ 0·01) and environmental (t = 3·0, 0·001 < P ≤ 0·01) correlates of PA. The multiple-mediators model showed that the mediating role of the combination of these psychosocial correlates was also significant (t = 6·2, P ≤ 0·001).

Adolescents with low family wealth scored lower on stage of change, awareness, modelling, self-efficacy and environmental correlates of PA, and higher on PA barriers, which in turn resulted in lower levels of moderate-to-vigorous PA. Future interventions should target these individual and environmental constructs in order to tackle and intervene on social inequalities in PA among adolescents.