Table 1 Unadjusted decline in FEV1 over 11 years, respiratory care utilisation and SF-36 summary score at follow-up (SAPALDIA 2 (2002)) stratified by modified GOLD† and symptom categories at SAPALDIA 1 (1991)
Mean (SD) FEV1 decline (ml/year)(n = 5498)p Value§Respiratory care utilisation(% (n))(n = 6670)p Value‡Mean (SD) PCS(n = 5000)p Value§Mean (SD) MCS(n = 5000)p Value§
Normal lung function†
    No symptom−34 (29)7.3 (265/3626)53.1 (6.7)51.5 (7.7)
    With symptom*−37 (30)<0.0114.7 (358/2434)<0.0150.6 (9.1)<0.0148.7 (9.4)<0.01
Stage 1 COPD†
    No symptom−38 (36)0.088.1 (24/295)0.6051.2 (8.2)<0.0152.5 (7.6)0.05
    With symptom*−44 (38)<0.0112.5 (28/224)<0.0148.7 (10.8)<0.0148.9 (10.1)<0.01
Stage 2–4 COPD†
    No symptom−25 (43)0.3323.4 (7/30)<0.0151.4 (4.4)0.0953.9 (6.3)0.08
    With symptom*−29 (39)0.3834.4 (21/61)<0.0144.2 (12.1)<0.0150.5 (9.8)0.54
  • *Report of chronic cough or phlegm or shortness of breath while walking (see online supplement for detailed questions).

  • †Prebronchodilator spirometry.

  • ‡χ2 test for comparison with reference category (“normal lung function, no symptom”).

  • §t test for unequal variances for comparison with reference category (“normal lung function, no symptom”).

  • COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 s; GOLD, Global Initiative for Chronic Obstructive Lung Disease; MCS, mental component summary of SF-36; PCS, physical component summary of SF-36.