Air Pollution and Emergency Department Visits for Suicide Attempts in Vancouver, Canada

Abstract

Background:Comorbidity of depression, heart disease, and migraine has been observed in clinical practice, while ambient air pollution has been identified among different risk factors for these health conditions. Suicide attempts and ideations as the result of depression may be linked to air pollution exposure. Therefore the effects of ambient air pollution on emergency department (ED) visits for suicide attempts were investigated.Methods:Emergency visit data were collected in a hospital in Vancouver, Canada. The generalized linear mixed models technique was applied in the analysis of these data. A natural hierarchical structure of the data was used to define the clusters, with days nested in a 3-level structure (day of week, month, year). Poisson models were fitted to the clustered counts of ED visits with a single air pollutant, temperature and relative humidity. In addition, the case-crossover methodology was used with the same data for comparison. The analysis was performed by gender (all, males, females) and month (all: January–December, warm: April–September, cold: October–March).Results:Both hierarchical and case-crossover methods confirmed positive and statistically significant associations among carbon monoxide (CO), nitrogen dioxide (NO2), sulphur dioxide (SO2), and particulate matter (PM10) for all suicide attempts in the cold period. The largest increase was observed for males in the cold period for a 1-day lagged exposure to NO2, with an excess risk of 23.9% (95% CI: 7.8, 42.4) and odds ratio of 1.21 (95% CI: 1.03, 1.41). In warm months the associations were not statistically significant, and the highest positive value was obtained for ozone lagged by 1 day.Conclusion:The results indicate a potential association between air pollution and emergency department visits for suicide attempts.

The effects of air pollution on individual psychological distress

“…Only a handful of studies have examined the association of air pollution with psychological health, despite growing evidence elucidating possible mechanisms to support such a relationship. Those studies that have considered the air pollution-psychological health link tend to rely on demographically 25,26,32 -and geographically-limited 24,33,34 samples at a single cross-section in time, and often utilize relatively crude measures of air pollution exposure 24 or mental health 28,29,30 .…”

“…The small body of research in this area has examined the association of air pollution with depressive symptoms 24,25 , anxiety 26 , suicide risk 27 , and associated emergency department visits 28,29,30 . Findings from this work are promising but not conclusive, as many of these studies tend to rely on small samples, utilize inconsistent measures and methodologies 31 , or are limited in demographic 25,26,32 , geographic 24,33,34 , and/or temporal 27 scope.…”

The impacts of air pollution on maternal stress during pregnancy

“…Air pollution was also reported to be linked with higher perceived stress levels in old men, particularly in cold months13. Studies also reported that short-term exposure to ambient air pollution was associated with increased emergency department visits because of depression or suicide attempts141516.…”

Air pollution, aeroallergens and suicidality: a review of the effects of air pollution and aeroallergens on suicidal behavior and an exploration of possible mechanisms

“…October-March). When segregated by season, the effects of air pollutants on suicide risks were statistically significant in the cooler months, in contrast to no statistically significant trends seen in the hot months (56,58). There also appears to be a critical transition period between spring and fall, where there is increased suicide risk with PM 10 and PM 2.5 (53,59).…”

“…The effects of air pollution and aeroallergens on suicidality have been scarcely investigated; however, there is initial evidence suggesting a positive correlation between air pollution, aeroallergens and suicidality (53)(54)(55)(56)(57)(58)(59)(60)(61)(62)(63)(64)(65)(66). Herein, the overarching aim is to provide a succinct review of the available literature on changes in air pollution, aeroallergens and their relationships to suicidal behavior, exploring potential mechanisms by which air pollution may influence suicide rates.…”