TABLE 4

Estimated differences in forced expiratory volume in 1 s (FEV1) with 95% confidence intervals (CIs) stratified by both changes in body mass index (BMI) and waist circumference (WC) at a fixed level of the other variable

Comparison between WC values cmBMI kg·m−2 (fixed level)FEV1 z-score (estimated difference)95% CI
Men90 versus 7020−0.44−0.78 to −0.10
105 versus 8525−0.56−0.70 to −0.42
115 versus 9530−0.83−0.96 to −0.69
Women85 versus 6520−0.21−0.35 to −0.06
95 versus 7525−0.36−0.45 to −0.28
105 versus 8530−0.34−0.48 to −0.20
Comparison between BMI values kg·m−2WC cm (fixed level)FEV1 z-score (estimated difference)95% CI
Men28 versus 22900.480.33–0.63
30 versus 241000.390.26–0.52
32 versus 261050.310.20–0.42
Women26 versus 20800.320.23–0.42
28 versus 22900.270.18–0.36
30 versus 24950.210.11–0.31