Heat stress, health and well-being: findings from a large national cohort of Thai adults

OBJECTIVES This study aims to examine the association between self-reported heat stress interference with daily activities (sleeping, work, travel, housework and exercise) and three graded-holistic health and well-being outcomes (energy, emotions and life satisfaction). DESIGN A cross-sectional study. SETTING The setting is tropical and developing countries as Thailand, where high temperature and high humidity are common, particularly during the hottest seasons. PARTICIPANTS This study is based on an ongoing national Thai Cohort Study of distance-learning open-university adult students (N=60 569) established in 2005 to study the health-risk transition. PRIMARY AND SECONDARY OUTCOME MEASURES Health impacts from heat stress in our study are categorised as physical health impacts (energy levels), mental health impacts (emotions) and well-being (life satisfaction). For each health and well-being outcome we report ORs and 95% CIs using multinomial logistic regression adjusting for a wide array of potential confounders. RESULTS Negative health and well-being outcomes (low-energy level, emotional problems and low life satisfaction) associated with increasing frequency of heat stress interfering with daily activities. Adjusted ORs for emotional problems were between 1.5 and 4.8 and in general worse than energy level (between 1.31 and 2.91) and life satisfaction (between 1.10 and 2.49). The worst health outcomes were when heat interfered with sleeping, followed by interference with daily travel, work, housework and exercise. CONCLUSIONS In tropical Thailand there already are substantial heat stress impacts on health and well-being. Increasing temperatures from climate change plus the ageing and urbanisation of the population could significantly worsen the situation. There is a need to improve public health surveillance and public awareness regarding the risks of heat stress in daily life.The International Collaborative Research Grants Scheme with joint grants from the Wellcome Trust UK (GR071587MA) and the Australian National Health and Medical Research Council (NHMRC 268055), and as a global health grant from the NHMRC (585426)

The association between overall health, psychological distress, and occupational heat stress among a large national cohort of 40,913 Thai workers

Background: Occupational heat stress is a well-known problem, particularly in tropical countries, affecting workers, health and well-being. There are very few recent studies that have reported on the effect of heat stress on mental health, or overall health in workers, although socioeconomic development and rapid urbanization in tropical developing countries like Thailand create working conditions in which heat stress is likely. Objective: This study is aimed at identifying the relationship between self-reported heat stress and psychological distress, and overall health status in Thai workers. Results: 18% of our large national cohort (>40,000 subjects) often works under heat stress conditions and males are exposed to heat stress more often than females. Furthermore, working under heat stress conditions is associated with both worse overall health and psychological distress (adjusted odds ratios ranging from 1.49 to 1.84). Conclusions: This association between occupational heat stress and worse health needs more public health attention and further development on occupational health interventions as climate change increases Thailand's temperatures

Heat stress, health and well-being: Findings from a large national cohort of Thai adults

Objectives: This study aims to examine the association between self-reported heat stress interference with daily activities (sleeping, work, travel, housework and exercise) and three graded-holistic health and well-being outcomes (energy, emotions and life satisfaction). Design: A cross-sectional study. Setting: The setting is tropical and developing countries as Thailand, where high temperature and high humidity are common, particularly during the hottest seasons. Participants: This study is based on an ongoing national Thai Cohort Study of distance-learning openuniversity adult students (N=60 569) established in 2005 to study the health-risk transition. Primary and secondary outcome measures: Health impacts from heat stress in our study are categorised as physical health impacts (energy levels), mental health impacts (emotions) and well-being (life satisfaction). For each health and well-being outcome we report ORs and 95% CIs using multinomial logistic regression adjusting for a wide array of potential confounders. Results: Negative health and well-being outcomes (low-energy level, emotional problems and low life satisfaction) associated with increasing frequency of heat stress interfering with daily activities. Adjusted ORs for emotional problems were between 1.5 and 4.8 and in general worse than energy level (between 1.31 and 2.91) and life satisfaction (between 1.10 and 2.49). The worst health outcomes were when heat interfered with sleeping, followed by interference with daily travel, work, housework and exercise. Conclusions: In tropical Thailand there already are substantial heat stress impacts on health and well-being. Increasing temperatures from climate change plus the ageing and urbanisation of the population could significantly worsen the situation. There is a need to improve public health surveillance and public awareness regarding the risks of heat stress in daily life

Non-fatal injury in Thailand from 2005 to 2013: Incidence trends and links to alcohol consumption patterns in the Thai Cohort Study

Background: We analyzed population-based injury trends and the association between injury and alcohol consumption patterns in Thailand, a middle-income country undergoing rapid social change. Methods: A nationwide cohort of 42 785 Thai adult Open University students, who were aged 15 to 87 years at enrolment, participated in cross-sectional assessments at baseline (2005) and 8 years later (2013). Incident non-fatal traffic and non-traffic injuries were recorded. Alcohol consumption patterns were categorized as follows: nondrinkers, occasional light drinkers, occasional heavy drinkers, regular drinkers, and ex-drinkers. Logistic regression was used to assess associations in 2005 and 2013 between injuries and alcohol consumption. We adjusted odds ratios (ORs) for socio-demographic factors, stress, health behaviors, and risk-taking behaviors. Results: Incidence estimates in 2013 were standardized to the age structure of 2005: the standardized rates were 10% (95% confidence interval [CI], 9.32-9.89) for participants with at least one non-traffic injury and 5% (95% CI, 4.86-5.29) for those with at least one traffic injury. Both standardized incidences for non-traffic and traffic injuries were significantly lower than corresponding rates in 2005 (20% and 6%, respectively). Alcohol consumption was significantly associated with non-traffic injury in 2005, but the association disappeared in 2013. For example, nontraffic injury was associated with regular drinking (adjusted OR 1.17; 95% CI, 1.01-1.40) in 2005, but not in 2013 (adjusted OR 0.89; 95% CI, 0.73-1.10). In both survey years, traffic injury was not associated with occasional heavy drinking when adjusted for health and risk-taking behavior. Conclusions: We examined non-fatal injury and the health-risk transition in Thailand in 2005 and 2013. Our data revealed decreases in alcohol consumption and non-fatal injury in the Thai Cohort between 2005 and 2013. Alcoholrelated injury in Thailand today could be amenable to preventive intervention

Heat stress causes substantial labour productivity loss in Australia

Heat stress at the workplace is an occupational health hazard that reduces labour productivity1. Assessment of productivity loss resulting from climate change has so far been based on physiological models of heat exposure1. These models suggest productivity may decrease by 11–27% by 2080 in hot regions such as Asia and the Caribbean2, and globally by up to 20% in hot months by 20503. Using an approach derived from health economics, we describe self-reported estimates of work absenteeism and reductions in work performance caused by heat in Australia during 2013/2014. We found that the annual costs were US$655 per person across a representative sample of 1,726 employed Australians. This represents an annual economic burden of around US$6.2 billion (95% CI: 5.2–7.3 billion) for the Australian workforce. This amounts to 0.33 to 0.47% of Australia’s GDP. Although this was a period when many Australians experienced what is at present considered exceptional heat4, our results suggest that adaptation measures to reduce heat effects should be adopted widely if severe economic impacts from labour productivity loss are to be avoided if heat waves become as frequent as predicted