COPD uncovered: an international survey on the impact of chronic obstructive pulmonary disease [COPD] on a working age population

Abstract

Background: Approximately 210 million people are estimated to have chronic obstructive pulmonary disease [COPD] worldwide. The burden of disease is known to be high, though less is known about those of a younger age. The aim of this study was to investigate the wider personal, economic and societal burden of COPD on a cross country working-age cohort.

Methods: A cross-country [Brazil, China, Germany, Turkey, US, UK] cross-sectional survey methodology was utilised to answer the research questions. 2426 participants aged 45-67 recruited via a number of recruitment methods specific to each country completed the full survey. Inclusion criteria were a recalled physician diagnosis of COPD, a smoking history of > 10 pack years and the use of COPD medications in the previous 3 months prior to questioning. The survey included items from the validated Work Productivity and Activity Impairment [WPAI] scale and the EuroQoL 5 Dimension [EQ-5D] scale. Disease severity was measured using the 5-point MRC [Medical Research Council] dyspnoea scale as a surrogate measure.

Results: 64% had either moderate [n = 1012] or severe [n = 521] COPD, although this varied by country. 75% of the cohort reported at least one comorbid condition. Quality of life declined with severity of illness [mild, mean EQ-5D score = 0.84; moderate 0.58; severe 0.41]. The annual cost of healthcare utilisation [excluding treatment costs and diagnostic tests] per individual was estimated to be $2,364 [£1,500]. For those remaining in active employment [n: 677]: lost time from work cost the individual an average of $880 [£556] per annum and lifetime losses of $7,365 [£4,661] amounting to $596,000 [£377,000] for the cohort. 447 [~40%] of the working population had retired prematurely because of COPD incurring individual estimated lifetime income losses of $316,000 [£200,000] or a combined total of $141 m [£89.6 m]. As the mean age of retirees was 58.3 and average time since retirement was 4 years, this suggests the average age of retirement is around 54. This would mean a high societal and economic impact in all study countries, particularly where typical state retirement ages are higher, for example in Brazil, Germany and the UK [65] and the US [65,66,67], compared to Turkey [58 for women, 60 for men] and China [60].

Conclusions: Although generalisation across a broader COPD population is limited due to the varied participant recruitment methods, these data nevertheless suggest that COPD has significant personal, economic and societal burden on working age people. Further efforts to improve COPD diagnosis and management are required.

Figure 1

CONSORT diagram showing recruitment of study participants. The CONSORT diagram shows the number of people involved at each stage of the survey recruitment process, according to the study criteria. Where a particular individual did not fulfil a particular criterion, they were not included in the study, and where such instances occurred, this is reflected along the left hand side of the figure. The right hand side reflects those included at each stage of the process, including the number of people [n]. The final figure included the respondents completing the full survey.

Figure 2

Severity [MRC] level analysed by country. This bar graph presents percentage data for severity analysed by country [severity measured using the MRC dyspnoea scale]. *percentage of respondents according to severity level as measured using the Medical Research Council [MRC] dyspnoea scale. There were no respondents in China who reported severe illness.

Figure 3

Healthcare utilisation analysed by country. The graphical representation here illustrates healthcare utilisation by utility type, and is presented based on a within-country analysis. *percentage of respondents utilising a healthcare resource within the last month. Respondents reported all utilities used within the last month.