Epidemiological study assessing the Burden of Illness related to COPD exacerbations in Québec

Trial description: Chronic Obstructive Pulmonary Disease (COPD) is a progressive chronic disease including emphysema and chronic bronchitis that affects over 770,000 Canadians or 4% of those over the age of 35 years. The prevalence however may be underreported since many patients are not diagnosed until later stages of the disease. The symptoms include shortness of breath, cough and sputum production with progressive deterioration that eventually leads to early mortality. The disease is the leading cause of all hospitalizations in Canada with an estimated annual direct health care costs over 1.5 billion during the last decade. To date there is no cure for COPD and patient management is focused on managing symptoms, reducing the severity and frequency of exacerbations and improving the patient’s quality of life. The predominant burden of illness driver for COPD is related to exacerbations and their consequences as well as the demand placed on the health care system for their management. Exacerbations are the primary cause of morbidity in COPD leading to accelerated disease progression with deterioration of pulmonary function and quality of life, and eventually shorter survival time. Higher frequency of exacerbations contributes to progressive deterioration of the patient that increase the demand for health care utilization, including physician, hospital and emergency room visits.The incidence of exacerbations in patients with moderate to severe COPD is estimated at 0.5 – 3.5 per year depending on the population, the region, the duration of follow up and the definition of exacerbations used. Management of exacerbations and their sequela are the major cost drivers of COPD. In the U.S., the direct health care costs related to COPD exacerbations exceed 20 billion per year. Dalal et al. have shown that the average direct annual health cost for the management of COPD in the U.S. was between $2,003 and $43,461 depending on the type of patient and care received. Patients requiring ICU treatment or a hospital admission had the highest costs. The data from the Resource Utilization Study in COPD (RUSIC) is a longitudinal Canadian study published in 2007. The study followed 609 patients with COPD recruited from 50 sites across Canada for 52 weeks. The results showed that the average overall cost for a moderate exacerbation was approximately $756 and that for a severe exacerbation was $9,953. Extrapolating these results to the Canadian population, the authors estimated the total cost of COPD exacerbations in Canada to be between $646 and $736 million. These results support the position that exacerbations are the main drivers of high cost for the management of COPD. However, one of the limitations of these studies is the fact that they are based on a sample of patients followed for relatively short periods. Therefore, the total cost of COPD and related exacerbations may be under-estimated due to limited follow up time and recall bias. Larger population based studies with unlimited follow up duration and unbiased ascertainment of health care utilization are required to provide a comprehensive assessment of the burden of illness related to COPD exacerbations. Patient, disease and treatment parameters that are independent risk factors for COPD exacerbations should also be identified on a large population scale. This information will be useful in developing tools that can identify patients that are at high risk for having frequent exacerbations and help to adjust their drug treatment according to their needs. The current study will address these needs by utilizing administrative databases from the Régie de l’Assurance Maladie du Québec (RAMQ), one of the most accurate sources of drug dispensation data on individuals in Québec.