Characteristics of people who died by suicide in a hospital district providing open dialogue-based psychiatric services: a nationwide cluster analysis.

Objective: Suicide rates vary regionally in Finland, with Western Lapland (WL) being a high-risk area. WL is also known for developing the Open Dialogue (OD)-based psychiatric services. This study aimed to compare the characteristics of suicide cases in WL to the rest of Finland to better understand the elevated suicide rate.

Materials and methods: Register-based data on all suicides (n = 4502) in Finland from 2017 to 2022 were used for clustering of demographic and clinical characteristics. Principal Component Analysis was applied for dimensionality reduction, followed by K-means clustering. Logistic regression was used to examine the association between WL and the clusters.

Results: WL recorded 66 suicides, with an average annual rate of 18 per 100,000, compared to 13.5 per 100,000 in the rest of Finland. Five clusters were identified from national data: (1) younger men with low service use, (2) individuals with repeated suicide attempts likely dying by self-poisoning, (3) socially integrated men with internalizing disorders, (4) older men with low service use more likely dying by firearm, and (5) individuals treated for severe mental disorders. WL suicides were more likely to belong to Cluster 4 (OR: 2, 95%CI: 1.2-3.3), with no other significant associations.

Conclusions: The Finnish hospital district providing OD-based psychiatric services had a higher suicide rate among older men using firearms with lower service contact, emphasizing the need for tailored prevention strategies. There was no indication that the region's elevated suicide rate could be explained by a higher rate of suicides in OD service users.