Acute Mental Health Impacts and Mid-Term Symptom Trajectories Following Wildfire Exposure
Highlights
- Wildfires can cause substantial psychological distress.
- Using a symptom-based approach to understand the immediate and medium-term mental health impacts of wildfires may inform timely interventions and disaster response strategies.
- Wildfires are increasing in size and expanding into additional geographic regions, with the smoke extending far beyond the fires themselves. As the numbers of people affected globally is rising rapidly, research to understand the health effects, both physical and mental, during and after the fires is more urgent than ever, and of mounting significance.
- This study highlights the need for early public health services and interventions to mitigate progression to more severe mental health conditions.
Abstract
1. Introduction
2. Methods
2.1. Study Setting
2.2. Study Design and Data Collection
2.3. Study Population
2.4. Outcomes
2.5. Exposures and Covariates
2.6. Statistical Analysis
3. Results
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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| Characteristic | N = 4346 1 |
|---|---|
| Age (years) | |
| 18–34 | 835 (19.2%) |
| <18 | 798 (18.4%) |
| 35–64 | 1936 (44.5%) |
| 65+ | 777 (17.9%) |
| Sex | |
| Female | 2418 (55.6%) |
| Male | 1928 (44.4%) |
| Race | |
| Non-Hispanic White | 3591 (82.6%) |
| Multiracial | 280 (6.4%) |
| White Hispanic | 276 (6.4%) |
| Other 2 | 199 (4.6%) |
| Socioeconomic status quartile | |
| Q1 (Lowest SES) | 1087 (25.0%) |
| Q2 | 1087 (25.0%) |
| Q3 | 1086 (25.0%) |
| Q4 (Highest SES) | 1086 (25.0%) |
| Live alone (Yes) | 269 (6.2%) |
| Prior asthma (Yes) | 628 (14.5%) |
| History of mental health condition(s) (Yes) | 442 (10.2%) |
| Prior physical disability (Yes) | 268 (6.2%) |
| Evacuation status (Yes) | 2221 (51.1%) |
| Wildfire-related home damage | |
| Not damaged | 2846 (65.5%) |
| Completely destroyed or significantly damaged | 1159 (26.7%) |
| Minor damage | 341 (7.8%) |
| Loss of family member or friend (Yes) | 468 (10.8%) |
| Lost job (Yes) | 1253 (28.8%) |
| Lost pet (Yes) | 580 (13.3%) |
| Characteristic | Count Component | Logistic Component (Odds of Having ≥1 vs. No Symptom | ||
|---|---|---|---|---|
| RR (95% CI) 2 | p-Value | OR (95% CI) 3 | p-Value | |
| Socio-demographics | ||||
| Age | ||||
| <18 | 0.79 (0.70–0.91) | <0.001 | 0.79 (0.65–0.97) | 0.024 |
| 18–34 (ref.) | ||||
| 35–64 | 1.00 (0.92–1.10) | 0.948 | 1.32 (1.12–1.56) | 0.001 |
| 65+ | 0.92 (0.82–1.03) | 0.162 | 1.32 (1.06–1.65) | 0.015 |
| Sex | ||||
| Female (ref.) | ||||
| Male | 0.84 (0.79–0.90) | <0.001 | 0.61 (0.54–0.67) | <0.001 |
| Race | ||||
| Non-Hispanic White (ref.) | ||||
| White Hispanic | 0.86 (0.72–1.02) | 0.074 | 1.29 (0.99–1.68) | 0.057 |
| Multiracial | 1.08 (0.94–1.24) | 0.267 | 0.80 (0.60–1.07) | 0.140 |
| Other 4 | 1.06 (0.87–1.28) | 0.572 | 0.84 (0.62–1.14) | 0.300 |
| SES | ||||
| Q1 (Lowest SES) (ref.) | ||||
| Q2 | 0.97 (0.87–1.09) | 0.638 | 0.75 (0.59–0.95) | 0.016 |
| Q3 | 1.00 (0.90–1.13) | 0.938 | 0.95 (0.76–1.20) | 0.700 |
| Q4 (Highest SES) | 0.90 (0.80–1.01) | 0.071 | 0.77 (0.62–0.97) | 0.025 |
| Living alone (Yes) | 1.05 (0.92–1.19) | 0.486 | 1.35 (1.03–1.78) | 0.031 |
| Baseline Comorbidities | ||||
| History of mental health condition (s) (Yes) | 1.22 (1.11–1.34) | <0.001 | 1.49 (1.20–1.84) | <0.001 |
| Prior physical disability (Yes) | 1.13 (1.01–1.27) | 0.033 | 1.27 (0.98–1.65) | 0.071 |
| Wildfire-related characteristics and loses | ||||
| Evacuated (Yes) | 1.10 (0.98–1.23) | 0.121 | 1.35 (1.10–1.68) | 0.003 |
| Home damage | ||||
| Not damaged (ref.) | ||||
| Completely destroyed or significantly damaged | 1.61 (1.43–1.81) | <0.001 | 1.63 (1.26–2.11) | <0.001 |
| Minor damage | 1.25 (1.06–1.48) | 0.007 | 1.28 (0.91–1.79) | 0.200 |
| Lost a family member or friend (Yes) | 1.14 (1.02–1.28) | 0.023 | 1.36 (1.03–1.78) | 0.028 |
| Lost pet (Yes) | 1.12 (1.01–1.26) | 0.038 | 1.11 (0.85–1.46) | 0.400 |
| Lost job (Yes) | 1.17 (1.07–1.27) | <0.001 | 1.20 (1.01–1.43) | 0.033 |
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Share and Cite
Gigoyan, L.; Dossett, M.L.; Conlon, K.C.; Chen, S.; Raffuse, S.M.; Hertz-Picciotto, I. Acute Mental Health Impacts and Mid-Term Symptom Trajectories Following Wildfire Exposure. Int. J. Environ. Res. Public Health 2026, 23, 1005. https://doi.org/10.3390/ijerph23081005
Gigoyan L, Dossett ML, Conlon KC, Chen S, Raffuse SM, Hertz-Picciotto I. Acute Mental Health Impacts and Mid-Term Symptom Trajectories Following Wildfire Exposure. International Journal of Environmental Research and Public Health. 2026; 23(8):1005. https://doi.org/10.3390/ijerph23081005
Chicago/Turabian StyleGigoyan, Lusine, Michelle L. Dossett, Kathryn C. Conlon, Shuai Chen, Sean M. Raffuse, and Irva Hertz-Picciotto. 2026. "Acute Mental Health Impacts and Mid-Term Symptom Trajectories Following Wildfire Exposure" International Journal of Environmental Research and Public Health 23, no. 8: 1005. https://doi.org/10.3390/ijerph23081005
APA StyleGigoyan, L., Dossett, M. L., Conlon, K. C., Chen, S., Raffuse, S. M., & Hertz-Picciotto, I. (2026). Acute Mental Health Impacts and Mid-Term Symptom Trajectories Following Wildfire Exposure. International Journal of Environmental Research and Public Health, 23(8), 1005. https://doi.org/10.3390/ijerph23081005

