Smoking history | Lung function | Seasonally adjusted plasma 25-hydroxyvitamin D quintiles | |||||
---|---|---|---|---|---|---|---|
1st (lowest) | 2nd | 3rd | 4th | 5th (highest) | P for trend | ||
All participants (N=5819) | Decline in FEV1 % predicted/year | 0.47 (0.38 to 0.56) | 0.29 (0.23 to 0.27) | 0.18 (0.11 to 0.26) | 0.24 (0.19 to 0.33) | 0.19 (0.13 to 0.28) | 2×10−5 |
Decline in FVC % predicted/year | 0.30 (0.18 to 0.38) | 0.16 (0.05 to 0.22) | 0.06 (0.00 to 0.14) | 0.14 (0.08 to 0.20) | 0.09 (0.02 to 0.16) | 4×10−4 | |
Continuous smokers (N=2250) | Decline in FEV1 % predicted/year | 0.69 (0.54 to 0.82) | 0.61 (0.41 to 0.71) | 0.32 (0.18 to 0.45) | 0.59 (0.44 to 0.71) | 0.43 (0.32 to 0.55) | 0.02 |
Decline in FVC % predicted/year | 0.46 (0.33 to 0.56) | 0.21 (0.12 to 0.31) | 0.12 (0.00 to 0.24) | 0.24 (0.11 to 0.40) | 0.16 (0.02 to 0.24) | 0.003 | |
Quitters (N=2295) | Decline in FEV1 % predicted/year | 0.26 (0.09 to 0.40) | 0.22 (0.11 to 0.31) | 0.14 (0.03 to 0.30) | 0.19 (0.09 to 0.28) | 0.13 (0.06 to 0.28) | 0.4 |
Decline in FVC % predicted/year | 0.12 (0.02 to 0.29) | 0.13 (−0.01 to 0.24) | 0.02 (−0.07 to 0.16) | 0.11 (0.02 to 0.21) | 0.13 (0.02 to 0.22) | 0.7 | |
Never smokers (N=1274) | Decline in FEV1 % predicted/year | 0.14 (−0.44 to 0.18) | 0.06 (−0.24 to 0.08) | 0.02 (−0.20 to 0.12) | 0.06 (−0.18 to 0.12) | 0.00 (−0.10 to 0.09) | 0.3 |
Decline in FVC % predicted/year | 0.08 (−0.12 to 0.37) | −0.02 (−0.16 to 0.26) | 0.06 (−0.05 to 0.15) | 0.06 (−0.08 to 0.19) | 0.00 (−0.09 to 0.11) | 0.2 |
FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity.