Impact of gastro-oesophageal reflux disease symptoms on COPD exacerbation

Terada, K; Muro, S; Sato, S; Ohara, T; Haruna, A; Marumo, S; Kinose, D; Ogawa, E; Hoshino, Y; Niimi, A; Terada, T; Mishima, M

doi:10.1136/thx.2007.092858

Impact of gastro-oesophageal reflux disease symptoms on COPD exacerbation

¹
Department of Respiratory Medicine, Kyoto University, Japan
²
Department of Experimental Therapeutics, Kyoto University Hospital, Japan
³
Terada Clinic, Respiratory Medicine and General Practice, Himeji City, Japan

Dr S Muro, Department of Respiratory Medicine, Kyoto University, 54, Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan; smuro{at}kuhp.kyoto-u.ac.jp

Received 1 November 2007
Accepted 16 April 2008
Published Online First 5 June 2008

Abstract

Background: The association between gastro-oesophageal reflux disease (GORD) and chronic obstructive pulmonary disease (COPD) exacerbation has so far remained unclear.

Objective: To prospectively establish the clinical significance of GORD symptoms on exacerbation.

Methods: 82 patients with COPD and 40 age matched controls were enrolled in this study. Symptoms were evaluated by a questionnaire using the Frequency Scale for the Symptoms of GORD (FSSG). Patients with COPD were prospectively surveyed for 6 months, and episodes of exacerbation were identified using a diary based on modified Anthonisen’s criteria. Exhaled breath condensate (EBC) pH was measured in both groups, and induced sputum was evaluated in patients with COPD.

Results: Positive GORD symptoms were reported in 22 (26.8%) patients with COPD and in five (12.5%) controls (p = 0.10). The frequency of exacerbations was significantly associated with the FSSG score (p = 0.03, r = 0.24, 95% CI 0.02 to 0.43). Multiple regression analysis revealed that GORD symptoms were significantly associated with the occurrence of exacerbations (p<0.01; relative risk 6.55, 95% CI 1.86 to 23.11). EBC pH was inversely correlated with FSSG score in both groups (p = 0.01, r = –0.37, 95% CI –0.55 to −0.14 in patients with COPD, and p<0.01, r = –0.45, 95% CI –0.67 to −0.16 in control subjects).

Conclusions: GORD symptoms were identified as an important factor associated with COPD exacerbation.

Footnotes

Funding: This work was supported in part by the Japan Society for the Promotion of Science Grant B 16390234.
Competing interests: None.
Ethics approval: The research protocol was approved by the ethics committee of Kyoto University.