Increased serum cotinine and obesity negatively impact asthma exacerbations and hospitalizations: A cross-sectional analysis of NHANES.

Background: Asthma is the most common non-communicable chronic airway disease worldwide. Obesity and cigarette use independently increase asthma morbidity and mortality. Current literature suggests that obesity and smoking synergistically increase asthma-related wheezing. Objective: To assess whether increased serum cotinine and obesity act synergistically to increase the likelihood of having an asthma exacerbation, emergency department (ED) visit, or hospitalization. Methods: A cross-sectional analysis of the 2011-2015 iterations of NHANES database was performed. Patients aged 18 years or greater with asthma were included. Serum cotinine was utilized as an accurate measurement of cigarette use. Logistic regression models were constructed to determine whether elevated serum cotinine and obesity were associated with self-reported asthma exacerbations, asthma-specific ED usage, and hospitalizations for any reason in the past year. Odds ratios were adjusted for age, gender, race, and ethnicity. Interactions were assessed by multiplying the adjusted effect sizes for elevated cotinine and obesity. Results: We identified 2179 ( Conclusion: Nearly one-third of patients with asthma were current smokers, and almost half were obese. This study identified elevated serum cotinine, a metabolite of cigarette use, and obesity as key risk factors for asthma exacerbations, asthma-related ED visits, and hospitalizations for any reason. Elevated serum cotinine and obesity were not found to act synergistically in increasing asthma exacerbations or ED visits. However, the presence of both risk factors increased the risk of currently having asthma (compared to a previous diagnosis) by 76%. Serum cotinine may be useful in predicting asthma outcomes.