COPD uncovered: a cross-sectional study to assess the socioeconomic burden of COPD in Japan

Ataru Igarashi,¹ Yoshinosuke Fukuchi,² Kazuto Hirata,³ Masakazu Ichinose,⁴ Atsushi Nagai,⁵ Masaharu Nishimura,⁶ Hajime Yoshisue,⁷ Kenichi Ohara,⁸ Jean-Bernard Gruenberger<sup>9

1</sup>Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan; ²Department of Respiratory Medicine, Graduate School of Medicine, Juntendo University, Tokyo, Japan; ³Department of Respiratory Medicine, Graduate School of Medicine, Osaka City University, Osaka, Japan; ⁴Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan; ⁵Research Institute for Respiratory Diseases, Shin-Yurigaoka General Hospital, Kawasaki City, Japan; ⁶Department of Pulmonary Medicine, Faculty School of Medicine, Hokkaido University, Hokkaido, Japan; ⁷Medical Division, Novartis Pharma K.K., Tokyo, Japan; ⁸Market Access Division, Novartis Pharma K.K., Tokyo, Japan; ⁹Market Access Division, Novartis Pharma AG, Basel, Switzerland

Background: COPD remains a major health problem in Japan. Patients with COPD experience a reduced quality of life (QoL) and have a higher chance of work impairment and productivity loss. However, there is a lack of data on the impact of COPD in terms of QoL and work activity impairment in Japan. This study assessed the socioeconomic burden of COPD in Japan and the impact it may have on the working age population.
Patients and methods: This was a 2-year retrospective chart review in COPD patients aged ≥40 years, with at least one health care visit to clinic or hospital in the previous 12 months. Patients were required to have available medical charts for at least the previous 24 months. Symptoms were assessed using COPD assessment test score; EuroQoL Group 5 Dimension (EQ-5D-5L) and work productivity and activity impairment general health questionnaires were used to evaluate health-related QoL and work productivity, and health care resource utilization data were obtained from clinical charts.
Results: In total, 71 patients aged <65 years, and 151 patients aged ≥65 years were included; the majority of patients had moderate or severe airflow limitation. Exacerbations (moderate or severe) were reported by ~35% of patients in both age groups; 52.1% and 62.9% of patients in the <65-year and ≥65-year age groups had COPD assessment test scores ≥10. EQ-5D-5L index scores in the <65-year and ≥65-year age groups were 0.79 and 0.77, respectively. Work productivity and activity impairment scores were higher in <65-year age group. Annual costs of health care resource use per patient in the <65-year and ≥65-year age groups were ¥438,975 (US$4,389) and ¥467,871 (US$4,678), respectively. Costs due to productivity loss were estimated to be ¥5,287,024 (US$52,870) in the <65-year age group and ¥3,018,974 (US$30,187) in the ≥65-year age group.
Conclusion: COPD represents a significant socioeconomic burden in Japan. Patients with COPD report significant use of health care resources. Higher impact on work impairment and productivity loss was observed frequently in the working age population.

Keywords: health-realted quality of life, chart review, EQ-5D-5L questionnaire, health care resource utilization, productivity loss, work impairment WPAI-GH