title: Analysis of comorbid factors that increase the COPD assessment test scores.
abstract: BACKGROUND
  The chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) is a concise health status measure for COPD. COPD patients have a variety of comorbidities, but little is known about their impact on quality of life. This study was designed to investigate comorbid factors that may contribute to high CAT scores.
  
  
  METHODS
  An observational study at Keio University and affiliated hospitals enrolled 336 COPD patients and 67 non-COPD subjects. Health status was assessed by the CAT, the St. Georges Respiratory Questionnaire (SGRQ), and all components of the Medical Outcomes Study Short-Form 36-Item (SF-36) version 2, which is a generic measure of health. Comorbidities were identified based on patients' reports, physicians' records, and questionnaires, including the Frequency Scale for the Symptoms of Gastro-esophageal reflux disease (GERD) and the Hospital Anxiety and Depression Scale. Dual X-ray absorptiometry measurements of bone mineral density were performed.
  
  
  RESULTS
  The CAT showed moderate-good correlations with the SGRQ and all components of the SF-36. The presence of GERD, depression, arrhythmia, and anxiety was significantly associated with a high CAT score in the COPD patients.
  
  
  CONCLUSIONS
  Symptomatic COPD patients have a high prevalence of comorbidities. A high CAT score should alert the clinician to a higher likelihood of certain comorbidities such as GERD and depression, because these diseases may co-exist unrecognized.
  
  
  BACKGROUND
  Clinical trial registered with UMIN (UMIN000003470).
authors: Masaki
authors: M
authors: Miyazaki
authors: Division of Pulmonary Medicine, Department of Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. htnakam@nifty.com.
authors: Hidetoshi
authors: H
authors: Nakamura
authors: Shotaro
authors: S
authors: Chubachi
authors: Mamoru
authors: M
authors: Sasaki
authors: Mizuha
authors: M
authors: Haraguchi
authors: Shuichi
authors: S
authors: Yoshida
authors: Keishi
authors: K
authors: Tsuduki
authors: Toru
authors: T
authors: Shirahata
authors: Saeko
authors: S
authors: Takahashi
authors: Naoto
authors: N
authors: Minematsu
authors: Hidefumi
authors: H
authors: Koh
authors: Morio
authors: M
authors: Nakamura
authors: Fumio
authors: F
authors: Sakamaki
authors: Takeshi
authors: T
authors: Terashima
authors: Koichi
authors: K
authors: Sayama
authors: Paul W
authors: PW
authors: Jones
authors: Koichiro
authors: K
authors: Asano
authors: Tomoko
authors: T
authors: Betsuyaku
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods / Q000592:standards; D000368:Aged; D000369:Aged, 80 and over; D001007:Anxiety / Q000000981:diagnostic imaging / Q000453:epidemiology; D015331:Cohort Studies; D015897:Comorbidity; D003863:Depression / Q000000981:diagnostic imaging / Q000453:epidemiology; D005260:Female; D005764:Gastroesophageal Reflux / Q000000981:diagnostic imaging / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D012720:Severity of Illness Index