Association between residence at high altitude and the incidence of depressive episodes in Ecuador

Depression is the main mental disorder in Latin America. Its etiology is multifactorial, encompassing genetic, sociodemographic, cultural and even environmental factors. Some studies have shown that living in high altitude regions may be related to depression. Therefore, this study aims to determine the correlation between altitude and the incidence of depressive episodes in Ecuador.

Cross-sectional analytical study of hospital discharge databases in Ecuador from 2018 to 2022. Relative risk and Pearson correlation were estimated and linear regression was performed to evaluate association.

6460 depressive episodes were observed in the 5 years of the study. The provinces located at high altitude (≥1500 m.a.s.l.) had the highest cumulative incidences per 100,000 inhabitants. These provinces are Tungurahua (81.4), Pichincha (68.8), Chimborazo (63.8), Imbabura (55.8) and Bolívar (51.1), respectively. The relative risk of residence at high altitude was RR=2.67 (95 % CI=2.54 - 2.81, p < 0.001), while the results of the linear regression between cumulative incidence per 100,000 and altitude were r=0.78, r2=0.61 and in the independent variable (altitude) t=5.84, p < 0.001.

A positive correlation was found between high-altitude residence and the incidence of depressive episodes, but due to the limitations of this research, further studies are required to corroborate this association, since the results may be influenced by other factors that were not considered.