Prognostic Factors in Heat Wave–Related Deaths<subtitle>A Meta-analysis</subtitle>

Abstract

Background: Although identifying individuals who are at increased risk of dying during heat waves and instituting protective measures represent an established strategy, the evidence supporting the components of this strategy and their strengths has yet to be evaluated. We conducted a meta-analysis of observational studies on risk and protective factors in heat wave-related deaths. Methods: Using the OVID interface, we searched Medline (1966-2006) and CINHAL (1982-2006) databases. The Web sites of the World Health Organization, Institut National de Veille Sanitaire, and Centers for Disease Control and Prevention were also visited. The search terms included heat wave, heat stroke, heatstroke, sunstroke, and heat stress disorders. Eligible studies were case-control or cohort studies. Odds ratios (ORs) and information on study quality were abstracted by 2 investigators independently. Six case-control studies involving 1065 heat wave-related deaths were identified. Results: Being confined to bed (OR, 6.44; 95% confidence interval [CI], 4.5-9.2), not leaving home daily (OR, 3.35; 95% CI, 1.6-6.9), and being unable to care for oneself (OR, 2.97; 95% CI, 1.8-4.8) were associated with the highest risk of death during heat waves. Preexisting psychiatric illness (OR, 3.61; 95% CI, 1.3-9.8) tripled the risk of death, followed by cardiovascular (OR, 2.48; 95% CI, 1.3-4.8) and pulmonary (OR, 1.61; 95% CI, 1.2-2.1) illness. Working home airconditioning (OR, 0.23; 95% CI, 0.1-0.6), visiting cool environments (OR, 0.34; 95% CI, 0.2-0.5), and increasing social contact (OR, 0.40; 95% CI, 0.2-0.8) were strongly associated with better outcomes. Taking extra showers or baths (OR, 0.32; 95% CI, 0.1-1.1) and using fans (OR, 0.60; 95% CI, 0.4-1.1) were associated with a trend toward lower risk of death. Conclusion: The present study identified several prognostic factors that could help to detect those individuals who are at highest risk during heat waves and to provide a basis for potential risk-reducing interventions in the setting of heat waves.

Prevention and management of health hazards related to heatwaves

“…In Italy, for example, the heat-health warning system (HHWS) has been assessed for its sensitivity and specificity of forecasting a meteorological condition that is linked to excess mortality ( 4). Hungary has carried out a telephone survey in 5 cities among ,500 responders to evaluate the communication campaign of its system ( 5). Results show that TV was the medium consulted most often for information (by 78% of the respondents), while the Internet was used least for information on heat and health.…”

“…Some people are less able to cope with heat stress than others. A wide range of chronic diseases and medical treatments, social isolation and some types of occupation increase the risk of heat stress in individuals (4,5). Across Europe, housing and socio-economic conditions showed varying influence on the impacts of heat on health in the populations.…”

An adaptation index to high summer heat associated with adverse health impacts in deprived neighborhoods

“…Passive variables do not contribute to building the index itself, but they serve more for interpretation and comparison purposes. They include features that may influence adaptation to heat (Basu and Samet 2002;Bouchama et al 2007;Kovats and Hajat 2008;Luber and McGeehin 2008;Lundgren and Jonsson 2012), namely: gender, age, gender crossed with age, being a recent immigrant, type of household, living in low-income housing, having air conditioning in the house (here, 80 % window air conditioner, see Bélanger et al 2014), as well as living in a city considered very hot based on average temperature observed over the last 30 years (Chebana et al 2013). Access to air conditioning was preferred among variables bearing on its usage (e.g., usage during the day), as respondents whose homes were equipped with air conditioning in general operated their air conditioner day and night during high summer heat (access and use: r>0.9).…”

Excess Heat-Related Mortality in Micro-Urban Heat Islands: A Case-only Study in Barcelona

“…Heat effects are particularly detrimental to certain sub-populations: the elderly (IÑIGUEZ et al 2010;O'NEILL et al 2009), the poor (O'NEILL et al 2009;BASU 2009), minorities (BASU 2009;SCHWARTZ 2005), the mentally ill (HANSEN et al 2008), outdoor workers (KINNEY et al 2008), the bedridden (BOUCHAMA et al 2007) and people who take certain types of medications that interfere with electrolytes and water balance (e.g., diuretics, anticholergic agents, and tranquilizers that impair sweating) (LUBER & MCGEEHIN 2008, HANSEN et al 2008JOHNSON et al 2009;MARTINN-LATRY et al 2007). Heat may kill so quickly that hospital admissions do not reflect the full scale of mortality (KOVATS & HAJAT 2008); some authors report that most victims are found dead in their residences (BOUCHAMA et al 2007).…”