Objective: Although it is believed that stress contributes to asthma, there are no data from studies in the general population to support this belief. To determine whether stress influences asthma in the general population, a database from a nationwide survey to evaluate the relationship between stress and asthma symptoms was used in the present study.
Methodology: A database generated by the National Health and Nutrition Examination Survey I (in South Korea, 1998) was used for this cross-sectional study. Stratified random samples of 9263 subjects, aged 20 years or older, were selected from the entire population of the country; 95% of these subjects responded. Among the responders, 5048 subjects aged 20-44 years were included in the study. Subjects were interviewed using a questionnaire. Multivariate analysis was performed using multiple logistic regression.
Results: The prevalence of wheeze and waking in the night because of cough or shortness of breath in the preceding 12 months was 12.9 and 13.5%, respectively. Multivariate analysis showed that the odds ratios for asthma symptoms increased according to the severity of stress reported by the subjects. When stress levels were classified into four categories of little, some, much and very much stress, the odds ratios for wheeze in the preceding 12 months were 1.7 (95% confidence interval (CI) 1.1, 2.5), 2.6 (95% CI 1.7, 4.0) and 3.6 (95% CI 2.1, 5.9) for subjects reporting some, much and very much stress, respectively, relative to those reporting little stress. Using the same stress-level classifications, the odds ratios for waking in the night because of cough or shortness of breath in the preceding 12 months were 1.5 (95% CI 1.0, 2.3), 2.4 (95% CI 1.6, 3.6) and 4.0 (95% CI 2.5, 6.4), respectively.
Conclusion: This cross-sectional study shows an association between stress and asthma symptoms in the general population of South Korea.