Forecasting the impact of means restriction on the suicide mortality rate in the Region of the Americas: an ecological modeling study

Background

The suicide mortality rate has been increasing in Region of the Americas, despite decreasing in all other World Health Organization (WHO) regions. Means restriction is an effective evidence-based intervention for suicide prevention. The objective of the current study was to estimate the impact of implementing national-level means restriction policies (i.e., firearm and pesticide restrictions) on the suicide mortality rate in the Region of the Americas.

Methods

In this ecological modeling study, two counterfactual scenarios were investigated using sex-specific suicide mortality data from the WHO Global Health Estimates database for 2000 to 2019. Forecasted sex-specific age-standardized suicide mortality rates were then estimated for each country for 2020 to 2030. Counterfactual scenario 1 involved modeling the impact of a firearm or pesticide restriction implemented in 2020 for those countries where the respective means accounted for 40% or more of all suicides for at least one sex in 2019, while in counterfactual scenario 2 this threshold was reduced to 20% or more.

Findings

It was estimated that if a firearm or pesticide restriction had been implemented in 2020 in those countries where the respective means accounted for 40% or more of all suicides for at least one sex in 2019, by 2030 the male and female suicide mortality rate in the Region of the Americas would be 20.5% (from 14.5 [95% Confidence Interval [CI]: 14.1, 15.0] per 100,000 males to 11.5 [95% CI: 11.1, 12.0] per 100,000 males) and 11.1% (from 4.5 [95% CI: 4.4, 4.7] per 100,000 females to 4.0 [95% CI: 3.9, 4.2] per 100,000 females) lower than the rate if no such restrictions were implemented, respectively. When the threshold was reduced to 20% or more, minimal additional gains in terms of number of suicides avoided and suicide mortality rate reduction would be achieved.

Interpretation

The implementation of a firearm or pesticide restriction policy in countries where the respective means account for a large proportion of suicides (e.g., at least 40%) could aid the Region of the Americas in achieving the WHO target of a one third reduction in the suicide mortality rate by 2030.

Funding

This work received no funding.