The burden of suicide across different altitudes: 11-year geodemographic analysis conducted in 221 cantons in Ecuador ranging from 0 to 4300 m of elevation.

Abstract

The World Health Organization and the Global Burden of Disease study estimate that almost 800 000 people die from suicide yearly. The role of non-traditional risk factors such as climate and high-altitude exposure are poorly understood. This study aims to determine a potential relationship between altitude exposure and suicide rates among 221 cantons located at different altitudes ranging from 0 to 4300 m. We conducted an 11-year, country-wide, population-based analysis on age- and gender-standardised suicide rates in Ecuador, based on the official data from the National Institute of Statistics, using all available self-harm death codes (ICD-10 codes X60-X84). A total of 11 280 cases of suicide were reported during 2011-2021. Suicide rates were higher among men (11.48/100 000). In terms of elevation, suicide rates were significantly higher among people from high-altitude cantons (3.7/100 000) versus those from low-altitude cantons. When applying the International Society Mountain Medicine categorisation, suicide rates were significantly higher at moderate- (4.3/100 000), high- (3.6/100 000) and very-high-altitude cantons (4.4/100 000) when compared with low-altitude locations (2.5/100 000). Ecuador is one of the few countries that has a vast range of cantons located at different altitudes. We found that living at higher elevations is positively associated with greater suicide rates. Although the rates are significantly greater as elevation increases, a clear linear relationship is not apparent, likely because of the interplay of socioeconomic factors, including urbanicity. The effect of chronic hypobaric hypoxia on mood cannot be ruled out, although the existence of causal mechanisms remains to be elucidated.