Table 3

Unadjusted and adjusted ratios in chronic obstructive pulmonary disease (COPD)-related hospital admissions and hospital days

Average number of COPD-related hospital admissions per patient (unadjusted)Adjusted COPD-related hospital admissions*
EnroleesNon-enroleesRatioIncidence rate ratio95% CI
Total sample excluding those who died†
 First year follow-up0.730.780.940.820.60 to 1.12
 Second year follow-up0.750.890.840.73‡0.54 to 1.00
Alive at start of each year†
 First year follow-up0.830.831.000.790.57 to 1.09
 Second year follow-up0.820.880.930.72‡0.52 to 0.99