Spatial and space-time clusters of suicides in the contiguous USA (2000-2019)

Abstract

Purpose: The present study investigates the spatiotemporal variations in suicide mortality and tests associations between several covariates and suicides for the years 20002019 in the contiguous USA. The epidemiological disease surveillance software was used to identify spatiotemporal variations in suicide mortality rates and to test for significant spatial and space-time clusters with elevated relative suicide risk.

Methods: The analysis was done with age-adjusted suicide mortality counts data from the Centers for Disease Control (CDC) with International Classification of Diseases (ICD)-10 codes. Specifically, data with codes ICD-10 codes X60-X84.9 and Y87.0, plus ICD-10 113 codes from the CDC, was used. Fourteen significant spatial clusters and five significant space-time clusters of suicide in the contiguous USA were found, including nine significant bivariate spatial clusters of suicide deaths and opioid deaths.

Results: Based on these data, there exist significant and non-random suicide mortality clusters after adjusting for multiple covariates or risk factors. The covariates studied provide evidence to develop a better understanding of possible associations in geographical areas where the suicide mortality rates are higher than expected. In addition, there is a significant association between several of the studied risk factors and suicide mortality. While most suicide clusters are also opioid clusters, there exist some clusters with high opioid deaths that are not suicide clusters.

Conclusions: These results have the potential to provide a scientific framework that is based on surveillance, allowing health agencies to intervene and reduce elevated rates of suicides in selected counties in the U.S. The study is limited due to the resolution of the data at the county level, and some covariate data was unavailable for the entire period of the study.

Keywords: Cluster analysis; Spatiotemporal; Suicide.