Overall and subgroup prevalence of self-reported asthma in US adults: a nationally representative cross-sectional study

Background: The purpose of this study is to determine the variations in the prevalence of self-reported asthma among the adult population in the United States of America (USA), analyzing demographic characteristics, physical indicators, living habits, and sarcopenia. Methods: 10,566 participants from the 2009 to 2018 National Health and Nutrition Examination Survey (NHANES) of the USA who were 20 years of age or older and not pregnant were included in the study. Results: The prevalence of patients with asthma varies by age, gender, and race. The weighted prevalence is 15.5%, estimated to represent 19.36 million people in the USA (95% CI, 14.5% to 16.6%). The prevalence of self-reported asthma decreases with age, with the highest prevalence among young adults aged 20-25 for both males and females. Females were also more susceptible to asthma compared to males. The increase in asthma prevalence attributed to smoking was most pronounced among African American and Caucasian participants (p < 0.05), while its effect on Mexican American and Asian participants was relatively minor. Notably, the prevalence of asthma was significantly higher in African American and Caucasian participants with sarcopenia compared to those without sarcopenia. Conclusions: The prevalence of asthma is associated to varying degrees with factors such as age, gender, smoking, and the presence of sarcopenia. The elevated prevalence of asthma among young people and females warrants attention. Intensifying efforts toward smoking cessation and the scientific management of sarcopenia could be instrumental in reducing the incidence of asthma.