Is pollen associated with suicide? That’s the question we sought to answer. Pollen related allergic rhinitis is associated with depressive symptoms, discomfort, pain, sleep disruptions, isolation and reduced quality of life in people who have them. Our team, led by UM researcher Dr. Rachel Bergmans, set out to test associations of suicide mortality in Ohio with pollen exposures using data from Ohio’s vital records and a novel prognostic, model based raster of daily pollen counts from Dr. Allison Steiner’s team at UM’s College of Engineering.
We explored associations of suicide with exposure to four types of pollens and the paper can be found here (Open access for 50 days). Suicide is serious. Though the causes of suicide are complex, pollen allergies are associated with depressive symptoms, isolation, pain, discomfort and for some, complete debilitation. #suicide#pollen#epidemiology
Background Seasonal trends in suicide mortality are observed worldwide, potentially aligning with the seasonal release of aeroallergens. However, only a handful of studies have examined whether aeroallergens increase the risk of suicide, with inconclusive results thus far. The goal of this study was to use a time-stratified case-crossover design to test associations of speciated aeroallergens (evergreen, deciduous, grass, and ragweed) with suicide deaths in Ohio, USA (2007–2015).
Methods Residential addresses for 12,646 persons who died by suicide were linked with environmental data at the 4–25 km grid scale including atmospheric aeroallergen concentrations, maximum temperature, sunlight, particulate matter <2.5 μm, and ozone. A case-crossover design was used to examine same-day and 7-day cumulative lag effects on suicide. Analyses were stratified by age group, gender, and educational level.
Results In general, associations were null between aeroallergens and suicide. Stratified analyses revealed a relationship between grass pollen and same-day suicide for women (OR = 3.84; 95% CI = 1.44, 10.22) and those with a high school degree or less (OR = 2.03; 95% CI = 1.18, 3.49).
Conclusions While aeroallergens were generally not significantly related to suicide in this sample, these findings provide suggestive evidence for an acute relationship of grass pollen with suicide for women and those with lower education levels. Further research is warranted to determine whether susceptibility to speciated aeroallergens may be driven by underlying biological mechanisms or variation in exposure levels.
We published a new paper on Covid-19 and ER visits for suicide attempts/self harm incidents in Epidemiology and Community Health today
Rachel Bergmans, an epidemiologist from the University of Michigan Institute for Social Research (and soon the University of Michigan Medical School) and I recently wrote a paper on the impact of Covid-19 and Covid-19 policy in the state of Michigan on emergency room visits for suicide and self harm incidents.
I am happy to say that it appeared today in Epidemiology and Community Health and encourage everyone to read it here.
Many worried that Covid-19 and the resulting “lockdown” measures would result in rapid increases in suicide attempts due to increased unemployment and social isolation. We did not find an increase in ER visits for self harm and suicide attempts at the University of Michigan Hospital in Ann Arbor, MI. In fact, we found a decline in visits that continued into the winter.
Though it is impossible to know (from this data) what the actual reasons for this decline were, these results suggest that the Covid-19 crisis might not be comparable to previous economic downturns. It might suggest that efforts to financially support those left out of work by the shutdown might mitigate the worst effects of an rapid unemployment.
I am very proud of this work, here is the abstract:
Objective Determine the early impact of the COVID-19 pandemic on emergency department (ED) encounters for suicide attempt and intentional self-harm at a regional tertiary academic medical centre in Washtenaw County, Michigan, which is one of the wealthier and more diverse counties in the state.
Methods Interrupted time series analysis of daily ED encounters from October 2015 through October 2020 for suicide attempt and intentional self-harm (subject n=3002; 62% female; 78% Caucasian) using an autoregressive integrated moving average modelling approach.
Results There were 39.9% (95% CI 22.9% to 53.1%) fewer ED encounters for suicide attempt and intentional self-harm during the first 12 weeks of the COVID-19 pandemic (ie, on or after 10 March 2020, when the first cases of COVID-19 were identified in Michigan).
Conclusions Fewer individuals sought emergency care for suicide-related behaviour during the earlier phase of the COVID-19 pandemic than expected when compared to prior years. This suggests initial outbreaks of COVID-19 and state of emergency executive orders did not increase suicide-related behaviour in the short term. More work is needed to determine long-term impacts of the COVID-19 pandemic on suicide-related behaviour and whether there are high-risk groups.