Table 2.
Association of alpha 1-antitrypsin protease inhibitor (PI) status with standardised lung function adjusted for age and sex
| Regression coefficient (95% CI) | |||
|---|---|---|---|
| Outcome | Cohort | MS vs MM | MZ vs MM† |
| Maximum FEV1 | BO | −0.05 (−0.36 to 0.27) | 0.45 (−0.14 to 1.04) |
| CaPS | 0.07 (−0.10 to 0.24) | 0.11 (−0.12 to 0.33) | |
| ELSA | 0.05 (−0.03 to 0.12) | 0.12* (0.01 to 0.23) | |
| HAS | −0.49* (−0.94 to −0.05) | 0.08 (−0.39 to 0.55) | |
| HCS | −0.01 (−0.10 to 0.09) | 0.05 (−0.10 to 0.19) | |
| LBC1921 | −0.06 (−0.31 to 0.19) | 0.16 (−0.22 to 0.54) | |
| NSHD | 0.02 (−0.09 to 0.13) | 0.18* (0.01 to 0.35) | |
| WHII | 0.05 (−0.03 to 0.12) | 0.18** (0.06 to 0.29) | |
| Combined FE | 0.03 (−0.01 to 0.07) | 0.13**** (0.07 to 0.19) | |
| Combined RE | 0.03 (−0.01 to 0.07) | 0.13**** (0.07 to 0.19) | |
| Estimated var‡ | 1.20e−13 (0.00e+00 to .) | 1.09e−19 (0.00e+00 to .) | |
| Maximum FVC | BO | 0.03 (−0.26 to 0.32) | 0.43 (−0.11 to 0.97) |
| CaPS | 0.08 (−0.10 to 0.26) | 0.15 (−0.09 to 0.39) | |
| ELSA | 0.02 (−0.05 to 0.09) | 0.12* (0.01 to 0.22) | |
| HAS | −0.35 (−0.73 to 0.03) | 0.33 (−0.09 to 0.74) | |
| HCS | −0.02 (−0.11 to 0.07) | 0.14* (0.01 to 0.27) | |
| LBC1921 | −0.07 (−0.32 to 0.17) | 0.20 (−0.17 to 0.56) | |
| NSHD | 0.02 (−0.09 to 0.13) | 0.20* (0.04 to 0.37) | |
| WHII | −0.01 (−0.08 to 0.07) | 0.19** (0.07 to 0.30) | |
| Combined FE | 0.01 (−0.03 to 0.04) | 0.16**** (0.10 to 0.22) | |
| Combined RE | 0.00 (−0.04 to 0.04) | 0.16**** (0.10 to 0.22) | |
| Estimated var‡ | 3.76e−15 (1.01e−28 to 1.40e−01) | 3.53e−19 (0.00e+00 to .) | |
Estimates for PI-SS, SZ and ZZ are provided in the online supplement.
*p<0.05, **p<0.01, ***p<0.001, ****p<0.0001.
†Exact p values for PI-MZ-FEV1 were 1.7×10−5 (FE) and 1.1×10−5 (RE); for PI-MZ-FVC were 5.2×10−8 (FE) and 3.2×10−8 (RE).
‡Estimated variance of the random slope on carrier status modelled by the RE model.
BO, Boyd Orr; CaPS, Caerphilly Prospective Study; ELSA, English Longitudinal Study of Ageing; FE, fixed effect; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; HAS; Hertfordshire Ageing Study; HCS, Hertfordshire Cohort Study; LBC1921, Lothian Birth Cohort 1921; NSHD, MRC National Survey of Health and Development; RE, random effect; WHII, Whitehall II Study.