Critical Inhaler Handling Error Is an Independent Risk Factor for Frequent Exacerbations of Chronic Obstructive Pulmonary Disease: Interim Results of a Single Center Prospective Study

Objective: Chronic obstructive pulmonary disease (COPD) acute exacerbations are significant causes of morbidity and mortality. Frequent exacerbator phenotypes are considered a distinct subgroup and this phenotype has a negative effect on lung function, quality of life, activity, hospital admission, and mortality. We assess inhaler handling technique and adherence, and evaluate risk factors associated with frequent exacerbations in COPD patients. Methods: This study was a cross-sectional, case-control study. We prospectively enrolled 189 COPD patients from Yeungnam University Hospital from January 2018 to November 2018. Subjects were tested regarding their inhaler technique in face-to-face interviews with an advanced practice nurse of inhaler upon study entry. Frequency of moderate to severe COPD exacerbations were reviewed via electronic medical records during 12 months prior to study entry. Frequent exacerbations were defined as >= 2 moderate to severe exacerbations in the prior 12 months. Multivariate logistic regression was performed to identify risk factors for frequent exacerbations. Results: Among 189 COPD patients, 50 (26.5%) were frequent exacerbators. Based on univariate analyses, body mass index (BMI) < 25 kg/m(2), lower forced expiratory volume in 1 s (FEV1), higher mMRC, lower feeling of satisfaction with the inhaler, and any critical errors were potential risk factors for frequent exacerbations. Multivariate logistic regression analyses revealed that BMI < 25 kg/m(2) (OR, 2.855, 95% CI, 1.247-6.534; p=0.013), higher mMRC (OR, 1.625, 95% CI, 1.072-2.463; p=0.022), and any critical error (OR, 2.020, 95% CI, 1.021-3.999; p=0.044) were risk factors. Conclusion: Any critical error, BMI < 25 kg/m(2) and high mMRC are independent risk factors for frequent exacerbations in COPD patients. Careful monitoring and education around inhaler devices, particularly in frequent exacerbators, are important components of COPD treatment.