BACKGROUND: Although age and regional climate are considered to have effects on the incidence ratio of heat-related illness, quantitative estimation of age or region on the effect of occurring temperature for heat stroke is limited. METHODS: By utilizing data on the number of daily heat-related ambulance transport (HAT) in each of three age groups (7-17, 18-64, 65 years old, or older) and 47 prefectures in Japan, and daily maximum temperature (DMT) or Wet Bulb Globe Temperature (DMW) of each prefecture for the summer season, the effects of age and region on heat-related illness were studied. Two-way ANOVA was used to analyze the significance of the effect of age and 10 regions in Japan on HAT. The population-weighted average of DMT or DMW measured at weather stations in each prefecture was used as DMT or DMW for each prefecture. DMT or DMW when HAT is one in 100,000 people (T RESULTS: HAT of each age category and prefecture was plotted nearly on the exponential function of corresponding DMT or DMW. Average R CONCLUSIONS Age and regional differences affected the incidence of HAT. Thus, it is recommended that public prevention measures for heat-related disorders take into consideration age and regional variability.
Adult ; Aged ; Ambulances ; Child ; Heat Stress Disorders/epidemiology* ; Hot Temperature ; Humans ; Incidence ; Temperature

PURPOSE: To evaluate the effect of heat wave on emergency department (ED) visits due to heat related illness, we developed an ED based active surveillance system. We want to identify epidemiology of ED visits due to heat related illness and determine the effect of heat index on daily ED visits due to heat related illness. METHODS: We developed an ED based active surveillance system for adults who visited the ED due to heat stroke, heat exhaustion, heat syncope, heat edema, and heat cramp. We collected demographic and clinical variables, risk factors, and heat index by standardized registry on the webpage. We operated the surveillance into 16 emergency departments in Daegu City from June to September 2011. We analyzed epidemiologic variables descriptively and assessed the effect of heat index on the number of daily ED visits by multivariate Poisson regression analysis. RESULTS: During the study period, 34 cases were registered and nine cases were heat stroke. Heat stroke patients were older, and had more unemployment status than those with other heat related illness (p<0.05). More ED visits due to heat related illness were observed during the danger period than during the cool period, classified by heat index severity (Adjusted odds ratio: 1.72, 95% CI: 1.33-2.23). Increasing heat index by one degree caused more ED visits due to heat related illness (Adjusted incident rate ratio: 1.13, 95% CI: 1.07-1.19). CONCLUSION: We developed an ED based active surveillance system and observed more elderly persons and lower educational level in patients with heat stroke. In addition, increase in heat index significantly affected more daily ED visits due to heat related illness.
Adult ; Aged ; Daegu ; Edema ; Emergency Service, Hospital* ; Epidemiology ; Extreme Heat ; Heat Exhaustion ; Heat Stress Disorders ; Heat Stroke ; Hot Temperature* ; Humans ; Infrared Rays ; Odds Ratio ; Public Health Surveillance ; Risk Factors ; Syncope ; Unemployment

OBJECTIVETo reduce health-related threats of heat waves, interventions have been implemented in many parts of the world. However, there is a lack of higher-level evidence concerning the intervention efficacy. This study aimed to determine the efficacy of an intervention to reduce the number of heat-related illnesses.

METHODSA quasi-experimental design was employed by two cross-sectional surveys in the year 2014 and 2015, including 2,240 participants and 2,356 participants, respectively. Each survey was designed to include one control group and one intervention group, which conducted in Licheng, China. A representative sample was selected using a multistage sampling method. Data, collected from questionnaires about heat waves in 2014 and 2015, were analyzed using a difference-in-difference analysis and cost effectiveness analysis. Outcomes included changes in the prevalence of heat-related illnesses and cost-effectiveness variables.

RESULTSRelative to the control participants, the prevalence of heat-related illness in the intervention participants decreased to a greater extent in rural areas than in urban areas (OR=0.495 vs. OR=1.281). Moreover, the cost-effectiveness ratio in the intervention group was less than that in the control group (US$15.06 vs. US$15.69 per participant). Furthermore, to avoid one additional patient, the incremental cost-effectiveness ratio showed that an additional US$14.47 would be needed for the intervention compared to when no intervention was applied.

CONCLUSIONThe intervention program may be considered a worthwhile investment for rural areas that are more likely to experience heat waves. Meanwhile, corresponding improving measures should be presented towards urban areas. Future research should examine whether the intervention strategies could be spread out in other domestic or international regions where heat waves are usually experienced.

Adolescent ; Adult ; Aged ; China ; epidemiology ; Community Networks ; Cost-Benefit Analysis ; Cross-Sectional Studies ; Female ; Heat Stress Disorders ; epidemiology ; prevention & control ; Hot Temperature ; adverse effects ; Humans ; Logistic Models ; Male ; Middle Aged ; Prevalence ; Young Adult