Kim MA, Suh MK, Park J, et al. - Researchers used data from the Korean Obstructive Lung Disease cohort and compared clinical features of COPD patients by symptom variability. They determined how clinical outcomes of COPD can be influenced by symptom variability during the first year of enrollment. They used the value of standard deviation (SD) of mMRC scores taken every 3 months during the observation period of the first year, to define symptom variability. They defined the consistent (SD of mMRC scores = 0) and variable (SD of mMRC scores > 0) groups of patients. Overall 407 patients were included, with age 67.2 years, 97.8% were male. A significant link of the variable group with annual exacerbators and frequent exacerbators was revealed in multivariate logistic regression analysis. Overall, higher exacerbation risk, lower lung function, and more severe respiratory symptoms may be seen among COPD patients with symptom variability.