Somatic symptoms, psychological distress and trauma after disasters: lessons from the 2014 Hazelwood mine fire and 2019–20 Black Summer bushfires

(2023) 23:1573 Gao et al. BMC Public Health https://doi.org/10.1186/s12889-023-16501-1 BMC Public Health Open Access RESEARCH Somatic symptoms, psychological distress and trauma after disasters: lessons from the 2014 Hazelwood mine fire and 2019– 20 Black Summer bushfires Caroline X. Gao1,2,3 , Jana Menssink2,3 , Timothy C. H. Campbell4 , Catherine L. Smith1 , Jillian F. Ikin1 , Tyler Lane1 , Michael J. Abramson1   and Matthew Carroll4*    Abstract Background Wildfires cause significant physical and mental ill-health. How physical and mental symptoms interact following wildfire smoke exposure is unclear, particularly in the context of repeated exposures. In this cross-sectional study we investigated how posttraumatic stress and general psychological distress associated with somatic symptoms in a community exposed to multiple smoke events. Methods A random weighted sample of 709 adults exposed to smoke during the 2014 Hazelwood coal mine fire in south-eastern Australia completed a survey in 2020. The survey coincided with the Black Summer wildfires that caused a similar period of smoke haze in the region. Participants self-reported somatic symptoms (PHQ-15) and mine fire-related posttraumatic stress (IES-R) experienced over the previous week, general psychological distress (K10) experienced over the previous four weeks, lifetime health diagnoses and demographic information. Associations between posttraumatic stress, general psychological distress, and each PHQ-15 somatic symptom were analysed using ordinal logistic regression models. Results Overall, 36.2% of participants reported moderate- or high-level somatic symptomology. The most frequent somatic symptoms were fatigue, limb pain, trouble sleeping, back pain, headaches, and shortness of breath. After controlling for confounding factors, general psychological distress and posttraumatic stress were independently associated with all somatic symptoms (except menstrual problems in females for posttraumatic stress). Conclusions Results highlight the high prevalence of somatic symptoms and their association with general psychological distress and posttraumatic stress within a community in the midst of a second large-scale smoke event. It is essential that healthcare providers and public health authorities consider the interconnections of these conditions when supporting communities affected by climate-related disasters. Keywords General psychological distress, Posttraumatic stress, Repeated disaster exposure, Smoke exposure, Somatic symptoms, Wildfires *Correspondence: Matthew Carroll Full list of author information is available at the end of the article © The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Gao et al. BMC Public Health (2023) 23:1573 Introduction In the context of climate change, weather-related disasters have become increasingly common, causing substantial health, social and economic impacts [1]. The proliferation of catastrophic wildfire events is perhaps the most salient example of the consequences of global warming [2, 3]. With fire seasons getting longer and fireprone areas increasing in number and size in many countries, wildfires are arguably the most frequently occurring type of environmental disaster in the world today, impacting an ever-growing number of people [4]. Wildfires pose a unique set of dangers and challenges to those they impact. They can quickly escalate into extremely large and complex situations that are unpredictable and difficult to contain [5]. Hence, they can become protracted public emergencies involving long periods of hazard, disruption, relocation, and recovery [6]. Wildfires emit large volumes of air-polluting smoke that can disperse to places far distant from the fire’s epicentre, with the potential to adversely affect large numbers of people [7]. Wildfires, particularly those of extended scale and duration, cause significant physical and mental ill-health [8]. Globally, between 2000 and 2016, over 33,000 deaths were attributable to wildfire smoke exposure [9]. Between 2013 and 2018, wildfire smoke in Canada was estimated to have a yearly economic burden of CDN$410 M–$1.8B for acute health impacts and CDN$4.3B–$19B for chronic health impacts [10]. The psychological sequelae of wildfire exposure may persist, increasing the risk of mental disorders for years after the event [11]. An important, yet sometimes overlooked, topic is the interaction between physical and mental health symptoms following climate-related disasters. Psychopathology, particularly posttraumatic stress symptomatology (PTSS) and posttraumatic stress disorder (PTSD), has been linked with a range of somatic (physical) symptoms, for example, persistent pain, fatigue, shortness of breath and gastrointestinal problems [12–14]. Somatic symptoms are highly prevalent among disaster-exposed communities (e.g., man-made disasters, earthquakes) [15–17]. Simultaneously, physical conditions can exacerbate psychological distress and illness [18]. However, the association between psychological distress and somatic symptoms following repeated large-scale smoke events is largely unknown. In 2014, the Hazelwood coal mine in eastern Victoria, Australia, was ignited by wildfires and burned for 45 days, covering surrounding areas in smoke. The mine fire was one of the worst pollution events recorded in Victoria [19], prompting considerable community concern regarding short and long-term health impacts. The Hazelwood Health Study (HHS; www.hazelwoodh Page 2 of 9 ealthstudy.org.au) was established to evaluate the health impacts arising from the mine fire. The HHS Adult Survey established and surveyed an adult population cohort in May 2016-February 2017 [20]. To further investigate longer-term psychological impacts, a follow-up Mental Health and Wellbeing Survey was conducted with a subsample of the cohort. The timing of the follow-up survey happened to coincide with the Black Summer wildfires (September 2 (...truncated)