Adaptation behaviors modify the effects of body fat on heat-related symptoms among Taiwanese elderly

Int J Hyg Environ Health. 2024 Jan:255:114296. doi: 10.1016/j.ijheh.2023.114296. Epub 2023 Nov 17.

Abstract

Background: The aging process increases body fat and susceptibility to heat-related illnesses. The relationship between body composition and symptoms associated with exposure to extreme heat among the elderly is unclear. Additionally, the influence of individual adaptive behaviors in mitigating these risks has not been adequately explored.

Objectives: This study aimed to evaluate the association between body composition and heat-related symptoms as well as the potential modifying effects of heat adaptation behavior.

Methods: The body composition of elderly individuals was measured using bioelectrical impedance analysis. Face-to-face interviews were conducted a year later to determine the heat-related symptoms and adaptive behaviors practiced for the extremely hot days of the previous year. The association between body composition indices and the presence of more than two symptoms was assessed using logistic regression analysis, while stratified analysis and interaction term in models were used to evaluate the effect modifications of adaptive behaviors.

Results: Of the 859 participants, 16% reported more than two heat-related symptoms. Increased body fat mass index (fat mass in kg/squared height in meters) was associated with an elevated risk of more heat-related symptoms (odds ratio 1.11, 95% confidence interval 1.02-1.20). Each combination of staying indoors, using an umbrella and hat, and using air conditioning at noon reduced the risk association between body fat and symptoms. For females, a combination of reducing physical activity and staying indoors provided similar protective effect. Surprisingly, bathing more frequently in hot weather with heated instead of non-heated water augmented the risk correlation. Neither fan usage nor window opening displayed protective effects.

Conclusions: Elevated body fat levels, indicative of obesity, corresponded with an increased risk of heat-related symptoms. Integrating multiple adaptive behaviors can diminish the negative health impact of body fat on heat-induced symptoms. However, certain commonly adopted practices might not confer expected benefits.

Keywords: Adaptation behavior; Body fat; Effect modification; Elderly; Heat weather; Obesity; Symptoms.

MeSH terms

  • Adaptation, Psychological
  • Adipose Tissue* / metabolism
  • Aged
  • Body Composition
  • Body Mass Index
  • Female
  • Hot Temperature*
  • Humans
  • Obesity