Introduction

Suicide has shown an international and national trend to increase, mainly in young people, together with seasonal behavior associated with high temperatures. Although Chihuahua saw the highest number of suicides and suicide attempts in 2016, there are no studies documenting their seasonal and trend behavior.

Objective

This study sought to analyze the trend and seasonality of completed suicides in the state of Chihuahua from 2008 to 2018.

Method

The number of deaths from intentionally self-inflicted injuries was obtained from INEGI. The absolute suicide rate was estimated, and a time series model applied to identify its trend and seasonality. In addition, environmental temperature was used as a predictor variable for the number of suicides through a Poisson model.

Results

A trend was found in the completed suicide rate from 2008 to 2018 in men and women, both separately and together (stationary R2 .73, .66 and .69, respectively), together with seasonality in both sexes (p < .002), with the highest figures being recorded in June and July. An increase of 1,028 suicides was found for every 1°C rise in temperature. In the 10-24 and 25-34 age groups, a linear increase in the suicide rate was observed during the period studied (R² > .7, p = .001).

Discussion and conclusion

Between 2008 and 2018, the suicide rate increased in the state of Chihuahua, mainly among those aged between 10 and 34. Moreover, suicide rates tend to increase during the months of June and July because of temperature.