Adherence to a COPD treatment guideline among patients in Hong Kong

Ka Pang Chan,1 Fanny WS Ko,1 Hok Sum Chan,2 Mo Lin Wong,3 Thomas YW Mok,4 Kah Lin Choo,5 David SC Hui1 1Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, 2Department of Medicine, Alice Ho Miu Ling Nethersole Hospital, 3Department of Medicine and Geriatrics, Caritas Medical Centre, 4Respiratory Medical Department, Kowloon Hospital, 5Department of Medicine, North District Hospital, Hong Kong Background: This study aimed to assess the adherence rate of pharmacological treatment to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guideline published in 2011 and the prevalence of comorbidities among patients with COPD in Hong Kong (HK).Methods: Patients were recruited from five tertiary respiratory centers and followed up for 12 months. Data on baseline physiological, spirometric parameters, use of COPD medications and coexisting comorbidities were collected. The relationship between guideline adherence rate and subsequent COPD exacerbations was assessed.Results: Altogether, 450 patients were recruited. The mean age was 73.7±8.5 years, and 92.2% of them were males. Approximately 95% of them were ever-smokers, and the mean post-bronchodilator (BD) forced expiratory volume in 1 second was 50.8%±21.7% predicted. The mean COPD Assessment Test and modified Medical Research Council Dyspnea Scale were 13.2±8.1 and 2.1±1.0, respectively. In all, five (1.1%), 164 (36.4%), eight (1.8%) and 273 (60.7%) patients belonged to COPD groups A, B, C and D, respectively. The guideline adherence rate for pharmacological treatment ranged from 47.7% to 58.1% in the three clinic visits over 12 months, with overprescription of inhaled corticosteroids (ICS) and underutilization of long-acting BDs in group B COPD patients. Guideline nonadherence was not associated with increased risk of exacerbation after adjustment of confounding variables. However, this study was not powered to assess a difference in exacerbations. In all, 80.9% of patients had at least one comorbidity.Conclusion: A suboptimal adherence to GOLD guideline 2011, with overprescription of ICS, was identified. The commonly found comorbidities also aligned with the trend observed in other observational cohorts. Keywords: COPD, GOLD guideline, adherence