Is COPD a Progressive Disease? A Long Term Bode Cohort Observation.
BACKGROUND
The Global Initiative for Obstructive Lung Diseases (GOLD) defines COPD as a disease that is usually progressive. GOLD also provides a spirometric classification of airflow limitation. However, little is known about the long-term changes of patients in different GOLD grades.


OBJECTIVE
Explore the proportion and characteristics of COPD patients that change their spirometric GOLD grade over long-term follow-up.


METHODS
Patients alive for at least 8 years since recruitment and those who died with at least 4 years of repeated spirometric measurements were selected from the BODE cohort database. We purposely included the group of non survivors to avoid a "survival selection" bias. The proportion of patients that had a change (improvement or worsening) in their spirometric GOLD grading was calculated and their characteristics compared with those that remained in the same grade.


RESULTS
A total of 318 patients were included in the survivor and 217 in the non-survivor groups. Nine percent of survivors and 11% of non survivors had an improvement of at least one GOLD grade. Seventy one percent of survivors and non-survivors remained in the same GOLD grade. Those that improved had a greater degree of airway obstruction at baseline.


CONCLUSIONS
In this selected population of COPD patients, a high proportion of patients remained in the same spirometric GOLD grade or improved in a long-term follow-up. These findings suggest that once diagnosed, COPD is usually a non-progressive disease.
Pulmonary Department, Clínica Universidad de Navarra, Pamplona, Spain.
Juan P
JP
de-Torres
Pulmonary Department, Hospital Universitario Miguel Servet, Instituto Aragones Ciencias Salud & CIBERES, Zaragoza, Spain.
Jose M
JM
Marín
Pulmonary Department, Brigham and Women's Hospital. Harvard Medical School, Boston, MA, United States of America.
Víctor
V
Pinto-Plata
Pulmonary Department, Brigham and Women's Hospital. Harvard Medical School, Boston, MA, United States of America.
Miguel
M
Divo
Pulmonary Department, Clínica Universidad de Navarra, Pamplona, Spain.
Pablo
P
Sanchez-Salcedo
Pulmonary Department, Clínica Universidad de Navarra, Pamplona, Spain.
Jorge
J
Zagaceta
Pulmonary Department, Clínica Universidad de Navarra, Pamplona, Spain.
Javier J
JJ
Zulueta
Pulmonary Department, Clínica Universidad de Navarra, Pamplona, Spain.
Juan
J
Berto
Pulmonary Department, Hospital Universitario Jose Negrín, Las Palmas de Gran Canaria, Spain.
Carlos
C
Cabrera
Pulmonary Department, Brigham and Women's Hospital. Harvard Medical School, Boston, MA, United States of America.
Bartolome R
BR
Celli
Pulmonary Department, Hospital Ntra Sra de Candelaria, Tenerife, Spain.
Ciro
C
Casanova
D000368:Aged; D018450:Disease Progression; D005260:Female; D006801:Humans; D008168:Lung / Q000473:pathology; D008297:Male; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000473:pathology*; D012720:Severity of Illness Index