Risk Factors for Frequent Exacerbations in Chronic Obstructive Pulmonary Disease

Introduction

Some chronic obstructive pulmonary disease (COPD) patients experience acute exacerbations frequently and are categorized as a distinct phenotype ‘frequent exacerbators’. This phenotype negatively impacts the pulmonary function, quality of life, activity, hospital admission and mortality. Correct use of inhaler improves the outcomes in COPD. However, earlier studies have reported unsatisfactory inhalation techniques and adherence to inhalers, thus affecting the disease control. There are few studies which have explored the association between mishandling of inhalers and clinical outcomes in COPD patients.

Aim

This study analyzed the frequency of critical errors for various inhaler devices and determined the risk factors associated with frequent exacerbations in patients with COPD.

Methods

Study Design

• Prospective, cross-sectional, case-control study

Treatment Strategy

• Cohort comprised 189 COPD patients
• Their inhaler handling technique and adherence was assessed in face-to-face interviews with an advanced practice nurse of inhaler upon study entry.
• Critical errors were defined as errors affecting the lung deposition of inhaled drug, resulting in little or no drug deposition
• Frequency of moderate to severe COPD exacerbations were assessed using 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.
• Risk factors for frequent exacerbations were identified using multivariate logistic regression models.

Endpoints

• Critical errors
• Frequency of exacerbations
• Risk factors  

Results

• The mean age of patients was 69.9 years and the mean body mass index (BMI) was 23.8 kg/m²
• Among 189 COPD patients using 233 inhaler devices were included, out of which 93.1% were males, 26.5% were frequent exacerbators and 23.3% were using multiple types of inhaler devices
• Atleast one error was observed in 42.9%
• Following were identified as the potential risk factors for frequent exacerbations as per the univariate and multivariate analyses (Table 1).

Conclusion

• Any critical error, body mass index (BMI) < 25 kg/m² and high modified Medical Research Council (mMRC) were independent risk factors for frequent exacerbations in patients with chronic obstructive pulmonary disease (COPD).
• COPD patients, especially frequent exacerbators should be carefully monitored and educated about correct handling of inhaler devices.

Int J Chron Obstruct Pulmon Dis. 2019 Dec 2;14:2767-2775. Doi: 10.2147/COPD.S234774.