Comparison of Initial BMI in Moderate to Severe Heat-related Illness Among Royal Thai Navy Task Force Trainees

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Supagarn Phivgategaew
Summon Chomchai
Narongpon Dumavibhat
Dusit Sujirarat


                  The aim of the study was to compare initial body mass index (BMI) and individual factors that contributed moderate to severe heat-related illness among Royal Thai Navy Task Force undergoing training. Cohort study was conducted with 209 samples. Anthropometric data, risk behavior, and medical record were collected prior to start of the training course. Temperature and relative humidity were observed along the study. Poisson regression statistic estimated the relative rate ratio (RR) with 95% confidence interval (CI).
            Among the 209 samples, 8 events were found to have moderate to severe heat-related illness. Incidence density rate was 0.7803 per 1000 person-days (95%CI = 0.3902-1.5604). From the medical record, body mass index over 23 kg/m2 influenced insignificant risk of event (RR = 2.835, 95%CI = 0.677-11.861). Multivariate poisson regression adjusted by age found a relationship between waist circumference (RR = 1.172, 95%CI = 1.042-1.318), body fat (RR = 1.257, 95%CI = 1.007-1.569), and body surface area (RR = 1.069, 95%CI = 1.006-1.135), respectively.
            There was relatively too small event to define dose-response relationship. Longitudinal data might be useful to determine more factors that influenced heat-related illness and develop risk score among Royal Thai Navy Task Force.


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