Table 3 Regression coefficients and 95% confidence intervals for the rate of FEV1 (ml/year) change between age 43 and 53 years by smoking trajectories, most recent smoking status and smoking status at 25 years*
Regression coefficient (95% CI)†
Men (n = 1234)Women (n = 1306)All (n = 2540)‡
Smoking trajectories (n)
    Never smoker (737)000
    Predominantly non-smoker (896)1.20 (−4.80 to 7.19)1.30 (−3.26 to 5.76)1.61 (−2.13 to 5.34)
    Predominantly smoker (532)−8.04 (−14.76 to −1.31)−6.37 (−11.58 to −1.16)−6.0 (−10.26 to −1.74)
    Lifelong smoker (375)−24.8 (−32.25 to −16.91)−15.44 (−21.20 to −9.68)−17.61 (−22.34 to −12.84)
Most recent smoking status (n)
    Never smoker (737)000
    Former smoker (909)−1.56 (−7.50 to 4.38)−2.51 (−7.15 to 2.12)0.82 (−4.59 to 2.94)
    Current smoker (894)−12.91 (−19.16 to −6.66)−6.13 (−10.53 to 1.73)−8.44 (−12.21 to −4.68)
Smoking status at 25 years (n)
    Never smoker (722)000
    Former smoker (588)1.17 (−5.61 to 7.96)0.39 (−4.57 to 5.35)0.5 (−3.65 to 4.71)
    Current smoker (839)−14.32 (−20.44 to −8.20)−10.1 (−14.72 to 5.48)−11.0 (−14.86 to −7.21)
    Missing (391)−6.34 (−13.69 to 1.02)−23.3 (−8.20 to 3.54)−3.40 (−8.13 to 1.33)
  • *Adjusted for FEV1 level at age 43 years (baseline) and height at age 53 years.

  • †Negative coefficient refers to a decline in lung function.

  • ‡n for sample with complete data.