Suicidal acts may cluster in time and space and lead to community concerns about further imitative suicidal episodes. Although suicide clusters have been researched in previous studies, less is known about the clustering of non-fatal suicidal behaviour (self-harm). Furthermore, most previous studies used crude temporal and spatial information, e.g., numbers aggregated by month and residence area, for cluster detection analysis. This study aimed to (i) identify space–time clusters of self-harm and suicide using daily incidence data and exact address and (ii) investigate the characteristics of cluster-related suicidal acts.

Data on emergency department presentations for self-harm and suicide deaths in Taipei City and New Taipei City, Taiwan, were used in this study. In all-age and age-specific analyses, self-harm and suicide clusters were identified using space–time permutation scan statistics. A cut-off of 0.10 for the p value was used to identify possible clusters. Logistic regression was used to investigate the characteristics associated with cluster-related episodes.

A total of 5,291 self-harm episodes and 1,406 suicides in Taipei City (2004–2006) and 20,531 self-harm episodes and 2,329 suicides in New Taipei City (2012–2016) were included in the analysis. In the two cities, two self-harm clusters (n [number of self-harm episodes or suicide deaths in the cluster] = 4 and 8 in Taipei City), four suicide clusters (n = 3 in Taipei City and n = 4, 11 and 4 in New Taipei City) and two self-harm and suicide combined clusters (n = 4 in Taipei City and n = 8 in New Taipei City) were identified. Space–time clusters of self-harm, suicide, and self-harm and suicide combined accounted for 0.05%, 0.59%, and 0.08% of the respective groups of suicidal acts. Cluster-related episodes of self-harm and suicide were more likely to be male (adjusted odds ratio [aOR] = 2.22, 95% confidence interval [CI] 1.26, 3.89) and young people aged 10–29 years (aOR = 2.72, 95% CI 1.43, 5.21) than their cluster-unrelated counterparts.

Space–time clusters of self-harm, suicide, and self-harm and suicide combined accounted for a relatively small proportion of suicidal acts and were associated with some sex/age characteristics. Focusing on suicide deaths alone may underestimate the size of some clusters and/or lead to some clusters being overlooked. Future research could consider combining self-harm and suicide data and use social connection information to investigate possible clusters of suicidal acts.

Attention-deficit/hyperactivity disorder (ADHD) is associated with a higher risk of burn injury than in the normal population. Nevertheless, the influence of methylphenidate (MPH) on the risk of burn injury remains unclear. This retrospective cohort study analysed the effect of MPH on the risk of burn injury in children with ADHD.

Data were from Taiwan's National Health Insurance Research Database (NHIRD). The sample comprised individuals younger than 18 years with a diagnosis of ADHD (n = 90 634) in Taiwan's NHIRD between January 1996 and December 2013. We examined the cumulative effect of MPH on burn injury risk using Cox proportional hazards models. We conducted a sensitivity analysis for immortal time bias using a time-dependent Cox model and within-patient comparisons using the self-controlled case series model.

Children with ADHD taking MPH had a reduced risk of burn injury, with a cumulative duration of treatment dose-related effect, compared with those not taking MPH. Compared with children with ADHD not taking MPH, the adjusted hazard ratio for burn injury was 0.70 in children taking MPH for <90 days (95% confidence interval (CI) 0.64–0.77) and 0.43 in children taking MPH for ≥90 days (95% CI 0.40–0.47), with a 50.8% preventable fraction. The negative association of MPH was replicated in age-stratified analysis using time-dependent Cox regression and self-controlled case series models.

This study showed that MPH treatment was associated with a lower risk of burn injury in a cumulative duration of treatment dose-related effect manner.

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.

Although teachers are the key participants in health-promoting schools (HPS) programme delivery, it is still unknown whether teachers are appropriate health information resources and role models for students with respect to healthy diets. The present study aimed to investigate the effects of implementing HPS programmes on teachers’ nutrition knowledge and diets.

One HPS programme aiming at dietary intervention (HP-D) and one HPS not aiming at dietary intervention (HP-ND) were selected, along with two non-health-promoting (NHP) schools matched for school size and urbanization level with the two HPS. All 361 teachers in the four schools were invited to participate, yielding a 78·4 % overall valid response rate. A structured, self-reported questionnaire was administered, with regression models used for statistical analysis.

Teachers in the HP-D group had a mean score of 21·1 on a range of 0–30 for nutrition knowledge, which was significantly higher than the mean scores of 18·5 in the HP-ND group and 19·1 in the NHP group (P < 0·001). Better dietary behaviours were also observed among HP-D teachers. Further, being a ‘health education’ course instructor was associated with significantly higher scores on nutrition knowledge (β = 2·6, P < 0·001) and vegetable and fruit consumption (β = 1·4, P = 0·02) in the HP-D group than in the NHP group. The HP-ND and NHP groups exhibited similar patterns of non-significant differences compared with the HP-D group.

Implementation of a coordinated HPS framework on nutrition and diet was positively correlated with schoolteachers’ nutrition knowledge and dietary intake.

To evaluate the effect on decrease in blood pressure of modifying risk factors for stroke, such as blood lipid profiles, diet habits and indices of body weight, through a family-based nutrition health education programme among hypertensive patients and pre-hypertensive subjects without taking any antihypertensive drugs.

This was a community-based prospective study. The study population was randomly selected from communities in Taipei; potential subjects were invited by telephone to participate.

After excluding subjects whose blood pressure was normal and those using antihypertensive drugs, there were 390 participants included in the study. Subjects in the intervention group (n 293) received nutrition health education on blood pressure control and stroke-related risk factor modification at each visit. Non-intervention subjects (n 97) only acquired a general education sheet available in clinics. The blood pressure of study subjects was measured at baseline and 6-month follow-up to evaluate the intervention’s effect on decrease in blood pressure.

Significant decreases of 2·0 mmHg and 5·9 mmHg in systolic blood pressure were observed both in pre-hypertensive and hypertensive subjects in the intervention group. Additionally, intervention subjects with improvement of total cholesterol and LDL cholesterol, decrease in indices of body weight and increase in consumption of fruit and vegetables also had significant lowering of blood pressure.

The present study provided evidence that the blood pressure of pre-hypertensive and hypertensive subjects could decrease significantly, without taking antihypertensive drugs, after modifying blood lipid profiles and waist by dietary habits changed through a family-based nutrition heath education programme, resulting in a significant effect on stroke risk reduction.