Efficacy of a digitally supported regional systems intervention for suicide prevention (SUPREMOCOL) in Noord-Brabant, the Netherlands.

OBJECTIVE: We evaluated the effect of a digitally supported systems intervention for suicide prevention (SUPREMOCOL) in Noord-Brabant, the Netherlands. METHOD: Non-randomized stepped wedge trial design (SWTD). Stepwise implementation in the five subregions of the systems intervention. Pre-post analysis for the whole province (Exact Rate Ratio Test, Poisson count). SWTD Hazard Ratios of suicides per person-years for subregional analysis of control versus intervention conditions over five times three months. Sensitivity analysis. RESULTS: Suicide rates dropped 17.8% (p = .013) from 14.4 suicides per 100,000 before the start of implementation of the systems intervention (2017), to 11.9 (2018) and 11.8 (2019) per 100, during implementation; a significant reduction (p = .043) compared to no changes in the rest of the Netherlands. Suicide rates dropped further by 21.5% (p = .002) to 11.3 suicides per 100,000 during sustained implementation in 2021. Sensitivity analysis confirmed the reduction (p = .02). The SWTD analysis over 15 months in 2018-2019 did not show a significant association of this reduction with implementation per subregional level, probably due to insufficient power given the short SWTD timeframe for implementation and low suicide rates per subregion. CONCLUSIONS: During the SUPREMOCOL systems intervention, over four years, there was a sustained and significant reduction of suicides in Noord-Brabant.

A regional systems intervention for suicide prevention in the Netherlands (SUPREMOCOL): study protocol with a stepped wedge trial design.

BACKGROUND: In the Netherlands, suicide rates showed a sharp incline and this pertains particularly to the province of Noord-Brabant, one of the southern provinces in the Netherlands. This calls for a regional suicide prevention effort. METHODS/DESIGN: Study protocol. A regional suicide prevention systems intervention is implemented and evaluated by a stepped wedge trial design in five specialist mental health institutions and their adherent chain partners. Our system intervention is called SUPREMOCOL, which stands for Suicide Prevention by Monitoring and Collaborative Care, and focuses on four pillars: 1) recognition of people at risk for suicide by the development and implementation of a monitoring system with decision aid, 2) swift access to specialist care of people at risk, 3) positioning nurse care managers for collaborative care case management, and 4) 12 months telephone follow up. Eligible patients are persons attempting suicide or expressing suicidal ideation. Primary outcome is number of completed suicides, as reported by Statistics Netherlands and regional Public Health Institutes. Secondary outcome is number of attempted suicides, as reported by the regional ambulance transport and police. Suicidal ideation of persons registered in the monitoring system will, be assessed by the PHQ-9 and SIDAS questionnaires at baseline and 3, 6, 9 and 12 months after registration, and used as exploratory process measure. The impact of the intervention will be evaluated by means of the RE-AIM dimensions reach, efficacy, adoption, implementation, and maintenance. Intervention integrity will be assessed and taken into account in the analysis. DISCUSSION: The present manuscript presents the design and development of the SUPREMOCOL study. The ultimate goal is to lower the completed suicides rate by 20%, compared to the control period and compared to other provinces in the Netherlands. Moreover, our goal is to provide specialist mental health institutions and chain partners with a sustainable and adoptable intervention for suicide prevention. TRIAL REGISTRATION: Netherlands Trial Register under registration number NL6935 (5 April 2018). This is the first version of the study protocol (September 2019).

Springtime Peaks and Christmas Troughs: A National Longitudinal Population-Based Study into Suicide Incidence Time Trends in the Netherlands.

BACKGROUND: Time trends are one of the most studied phenomena in suicide research; however, evidence for time trends in the Dutch population remains understudied. Insight into time trends can contribute to the development of effective suicide prevention strategies. METHODS: Time trends in national daily and monthly data of 33,224 suicide events that occurred in the Netherlands from 1995 to 2015 were examined, as well as the influence of age, gender, and province, in a longitudinal population-based design with Poisson regression analyses and Bayesian change point analyses. RESULTS: Suicide incidence among Dutch residents increased from 2007 until 2015 by 38%. Suicide rates peak in spring, up to 8% higher than in summer (p < 0.001). Suicide incidence was 42% lower at Christmas, compared to the December-average (IRR = 0.580, p < 0.001). After Christmas, a substantial increase occurred on January 1, which remained high during the first weeks of the new year. Suicide occurred more than twice as often in men than in women. For both genders, the results indicated a spring time peak in suicide incidence and a trough at Christmas. Suicide rates were highest in the elderly (age group, 80+), and no evidence was found of a differential effect by season in the age groups with regard to suicide incidence. No interaction effect was found with regard to province of residence for both season and Christmas, indicating that no evidence was found that these time trends had differential effects in the Dutch provinces in terms of suicide incidence. CONCLUSION: Evidence was found for time trends in suicide incidence in the Netherlands. It is recommended to plan (mental) health care services to be available especially at high-risk moments, at spring time, and in the beginning of January. Further research is needed to explore the protective effect of Christmas in suicide incidence.