title: New GOLD classification: longitudinal data on group assignment.
abstract: BACKGROUND
  Little is known about the longitudinal changes associated with using the 2013 update of the multidimensional GOLD strategy for chronic obstructive pulmonary disease (COPD).
  
  
  OBJECTIVE
  To determine the COPD patient distribution of the new GOLD proposal and evaluate how this classification changes over one year compared with the previous GOLD staging based on spirometry only.
  
  
  METHODS
  We analyzed data from the CHAIN study, a multicenter observational Spanish cohort of COPD patients who are monitored annually. Categories were defined according to the proposed GOLD: FEV1%, mMRC dyspnea, COPD Assessment Test (CAT), Clinical COPD Questionnaire (CCQ), and exacerbations-hospitalizations. One-year follow-up information was available for all variables except CCQ data.
  
  
  RESULTS
  At baseline, 828 stable COPD patients were evaluated. On the basis of mMRC dyspnea versus CAT, the patients were distributed as follows: 38.2% vs. 27.2% in group A, 17.6% vs. 28.3% in group B, 15.8% vs. 12.9% in group C, and 28.4% vs. 31.6% in group D. Information was available for 526 patients at one year: 64.2% of patients remained in the same group but groups C and D show different degrees of variability. The annual progression by group was mainly associated with one-year changes in CAT scores (RR, 1.138; 95%CI: 1.074-1.206) and BODE index values (RR, 2.012; 95%CI: 1.487-2.722).
  
  
  CONCLUSIONS
  In the new GOLD grading classification, the type of tool used to determine the level of symptoms can substantially alter the group assignment. A change in category after one year was associated with longitudinal changes in the CAT and BODE index.
authors.affiliation: Pulmonary Department, Hospital Universitario Ntra, Sra, de La Candelaria, Santa Cruz de Tenerife, Tenerife, Spain. casanovaciro@gmail.com.
authors.forename: Ciro
authors.initials: C
authors.lastname: Casanova
authors.forename: Jose M
authors.initials: JM
authors.lastname: Marin
authors.forename: Cristina
authors.initials: C
authors.lastname: Martinez-Gonzalez
authors.forename: Pilar
authors.initials: P
authors.lastname: de Lucas-Ramos
authors.forename: Isabel
authors.initials: I
authors.lastname: Mir-Viladrich
authors.forename: Borja
authors.initials: B
authors.lastname: Cosio
authors.forename: German
authors.initials: G
authors.lastname: Peces-Barba
authors.forename: Miryam
authors.initials: M
authors.lastname: Calle-Rubio
authors.forename: Ingrid
authors.initials: I
authors.lastname: Solanes-García
authors.forename: Ramón
authors.initials: R
authors.lastname: Agüero
authors.forename: Alfredo
authors.initials: A
authors.lastname: de Diego-Damia
authors.forename: Nuria
authors.initials: N
authors.lastname: Feu-Collado
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Alfageme
authors.forename: Rosa
authors.initials: R
authors.lastname: Irigaray
authors.forename: Eva
authors.initials: E
authors.lastname: Balcells
authors.forename: Antonia
authors.initials: A
authors.lastname: Llunell
authors.forename: Juan Bautista
authors.initials: JB
authors.lastname: Galdiz
authors.forename: Margarita
authors.initials: M
authors.lastname: Marín
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Soler-Cataluña
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Lopez-Campos
authors.forename: Joan B
authors.initials: JB
authors.lastname: Soriano
authors.forename: Juan P
authors.initials: JP
authors.lastname: de-Torres
mesh_terms: D000368:Aged; D015331:Cohort Studies; D016208:Databases, Factual / Q000145:classification* / Q000639:trends; D005260:Female; D005500:Follow-Up Studies; D014943:Global Health / Q000145:classification*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000145:classification* / Q000175:diagnosis* / Q000453:epidemiology; D013030:Spain / Q000453:epidemiology