Bipolar disorder is a chronic mental disorder related to cognitive deficits. Low serum vitamin D levels are significantly associated with compromised cognition in neuropsychiatric disorders. Although patients with bipolar disorder frequently exhibit hypovitaminosis D, the association between vitamin D and cognition in bipolar disorder, and their neuroaxonal integrity, is unclear.

To investigate the interaction effects between vitamin D and neurofilament light chain (NfL) levels on cognitive domains in bipolar disorder.

Serum vitamin D and NfL levels were determined in 100 euthymic patients with bipolar disorder in a cross-sectional study. Cognitive function was measured with the Brief Assessment of Cognition in Affective Disorders. We stratified by age groups and used general linear models to identify associations between vitamin D and NfL levels and their interaction effects on cognitive domains.

The mean vitamin D and NfL levels were 16.46 ng/nL and 11.10 pg/mL, respectively; 72% of patients were vitamin D deficient. In the older group, more frequent hospital admissions and lower physical activity were identified in the group with versus without vitamin D deficiency. The age-modified interaction effect of vitamin D and NfL was associated with composite neurocognitive scores and verbal fluency in both age groups, and with processing speed domain in the younger group.

We observed a high vitamin D deficiency prevalence in bipolar disorder. We identified the interaction of vitamin D and NfL on cognitive domains, and the effect was modified by age. Longitudinal or randomised controlled studies enrolling patients with various illness durations and mood statuses are required to validate our findings.

This study examined the pattern of medical utilization and the distribution of comorbidities shortly before death among adolescents who died from suicide and compared these data with those of living controls.

From Taiwan's National Health Insurance Research Database, this study identified adolescents aged 10–19 years who died from suicide (n = 935) between 1 January 2000, and 31 December 2016, by linking each patient with the national mortality database. The researchers conducted a nested case–control study through risk set sampling, and for each case, 20 age- and sex-matched controls (n = 18 700) were selected from the general population. The researchers applied conditional logistic regression to investigate differences in medical utilization and physical and psychiatric comorbidities between cases and controls.

Cases had a higher proportion of contact with the psychiatric department but a similar proportion of contact with any non-psychiatric medical department within 1 year before suicide compared with controls. There were 18.6% of adolescent suicide victims who only had contacted with a psychiatric department 3 months before suicide. Moreover, cases had a higher proportion of contact with non-psychiatric services within 3 months before suicide, particularly with emergency, surgery, and internal medicine departments. Cases had higher risks of several psychiatric disorders and physical illnesses, including heart diseases, pneumonia, and ulcer disease, than did controls.

The findings of increased medical utilization and higher risks of physical and psychiatric comorbidities in adolescent suicide victims are crucial for developing specific interventions to prevent suicide in this population.

Evidence on sex-specific incidence and comorbidity risk factors of suicide among patients with bipolar disorder is scarce. This study investigated the sex-specific risk profiles for suicide among the bipolar disorder population in terms of incidence, healthcare utilization and comorbidity.

Using data from the Taiwan National Health Insurance Research Database between 1 January 2000 and 31 December 2016, this nationwide cohort study included patients with bipolar disorder (N = 46 490) and individuals representative of the general population (N = 185 960) matched by age and sex at a 1:4 ratio. Mortality rate ratios (MRRs) of suicide were calculated between suicide rates of bipolar disorder cohort and general population. In addition, a nested case–control study (1428 cases died by suicide and 5710 living controls) was conducted in the bipolar disorder cohort to examine the sex-specific risk of healthcare utilization and comorbidities.

Suicide risk was considerably higher in the cohort (MRR = 21.9) than in the general population, especially among women (MRR = 35.6). Sex-stratified analyses revealed distinct healthcare utilization patterns and physical comorbidity risk profiles between the sexes. Although female patients who died by suicide had higher risks of nonhypertensive cardiovascular disease, pneumonia, chronic kidney disease, peptic ulcer, irritable bowel syndrome, and sepsis compared to their living counterparts, male patients who died by suicide had higher risks of chronic kidney disease and sepsis compared to the living controls.

Patients with bipolar disorder who died by suicide had sex-specific risk profiles in incidence and physical comorbidities. Identifying these modifiable risk factors may guide interventions for suicide risk reduction.

Research on the risk of stroke following the use of mood stabilisers specific to patients with bipolar disorder is limited.

In this study, we investigated the risk of stroke following the exposure to mood stabilisers in patients with bipolar disorder.

Data for this nationwide population-based study were derived from the Taiwan National Health Insurance Research Database. Among a retrospective cohort of patients with bipolar disorder (n = 19 433), 609 new-onset cases of stroke were identified from 1999 to 2012. A case–crossover study design utilising 14-day windows was applied to assess the acute exposure effect of individual mood stabilisers on the risk of ischaemic, haemorrhagic and other types of stroke in patients with bipolar disorder.

Mood stabilisers as a group were significantly associated with the increased risk of stroke in patients with bipolar disorder (adjusted risk ratio, 1.26; P = 0.041). Among individual mood stabilisers, acute exposure to carbamazepine had the highest risk of stroke (adjusted risk ratio, 1.68; P = 0.018), particularly the ischaemic type (adjusted risk ratio, 1.81; P = 0.037). In addition, acute exposure to valproic acid elevated the risk of haemorrhagic stroke (adjusted risk ratio, 1.76; P = 0.022). In contrast, acute exposure to lithium and lamotrigine did not significantly increase the risk of any type of stroke.

Use of carbamazepine and valproic acid, but not lithium and lamotrigine, is associated with increased risk of stroke in patients with bipolar disorder.

None.

Cancer is a serious public health problem worldwide, and its relationship with affective disorders is not clear.

To investigate alcohol- and tobacco-related cancer risk among patients with affective disorders in a large Taiwanese cohort.

Records of newly admitted patients with affective disorders from January 1997 through December 2002 were retrieved from the Psychiatric Inpatient Medical Claims database in Taiwan. Cancers were stratified by site and grouped into tobacco- or alcohol-related cancers. Standardised incidence ratios (SIRs) were calculated to compare the risk of cancer between those with affective disorders and the general population.

Some 10 207 patients with bipolar disorder and 9826 with major depression were included. The risk of cancer was higher in patients with major depression (SIR = 2.01, 95% CI 1.85–2.19) than in those with bipolar disorder (SIR 1.39, 95% CI 1.26–1.53). The elevated cancer risk among individuals ever admitted to hospital for affective disorders was more pronounced in tobacco- and/or alcohol-related cancers.

Elevated cancer risk was found in patients who had received in-patient care for affective disorders. They require holistic approaches to lifestyle behaviours and associated cancer risks.

Repeat self-harm is an important risk factor for suicide. Few studies have explored risk factors for non-fatal repeat self-harm in Asia.

To investigate the risk of non-fatal repeat self-harm in a large cohort of patients presenting to hospital in Taipei City, Taiwan.

Prospective cohort study of 7601 patients with self-harm presenting to emergency departments (January 2004–December 2006). Survival analysis was used to examine the rates, timing and factors associated with repeat self-harm.

In total 778 (10.2%) patients presented to hospital with one or more further episodes of self-harm. The cumulative risk of non-fatal repetition within 1 year of a self-harm episode was 9.3% (95% CI 8.7–10.1). The median time to repetition within 1 year was 105 days. Females had a higher incidence of repeat self-harm than males (adjusted hazard ratio 1.25, 95% CI 1.05–1.48) but males had shorter median time to repetition (107 v. 80 days). Other independent risk factors for repeat self-harm within 1 year of an index episode were: young age, self-harm by medicine overdose and increasing number of repeat episodes of self-harm.

The risk of non-fatal repeat self-harm in Taipei City is lower than that seen in the West. Risk factors for repeat non-fatal self-harm differ from those for fatal self-harm. The first 3 months after self-harm is a crucial period for intervention.

Most previous studies of long-term mortality risk following self-harm have been conducted in Western countries with few studies from Asia.

To investigate suicide and non-suicide mortality after non-fatal self-harm in Taipei City, Taiwan.

Prospective cohort study (median follow-up 3.3 years) of 7601 individuals presenting to hospital with self-harm (January 2004 to December 2006). Standardised mortality ratios (SMRs) for suicide and non-suicide mortality were calculated.

Suicide risk in the year following self-harm was over 100 times higher than in the general population (SMR = 119.6, 95% CI 99.6–142.5). Males and middle-aged and older adults had the highest subsequent risk of suicide. Compared with people who took an overdose, individuals who used hanging or charcoal burning in their index episode had the highest risk of suicide. For non-suicide mortality the SMRs were 6.7 (95% CI 5.7–7.8) in the first year and 4.4 (95% CI 3.9–4.9) during the whole follow-up period.

Patterns of increased all-cause and suicide mortality following an episode of self-harm are similar in Taipei City to those seen in Western countries. Designing better aftercare following non-fatal self-harm, particularly for those with underlying physical disorders or who have used lethal self-harm methods, should be a priority for suicide prevention programmes in Asia.