Table 4

Estimates of the expected change during follow-up for lung function z-scores per unit change in exposure variables in separate analytical models including (A) dust exposure, (B) endotoxin exposure, (C) farm type and (D) farm status (A, B, C for current and ex-farmers together, D comparing current and ex-farmers)

Regression models	ΔzFEV1			ΔzFVC			ΔzRatio
Regression models	R²	E (95% CI)	p Value	R²	E (95% CI)	p Value	R²	E (95% CI)	p Value
(A) Dust: (n=892)	0.14			0.24			0.06
1st quartile		0	–		0	–		0	–
2nd quartile		−0.06 (−0.17 to 0.06)	0.359		−0.01 (−0.13 to 0.10)	0.816		−0.06 (−0.21 to 0.10)	0.468
3rd quartile		−0.03 (−0.15 to 0.09)	0.590		−0.04 (−0.15 to 0.08)	0.529		−0.01 (−0.17 to 0.14)	0.880
4th quartile		−0.02 (−0.14 to 0.10)	0.733		0.03 (−0.09 to 0.15)	0.619		−0.09 (−0.25 to 0.06)	0.245
(B) Endotoxin: (n=892)	0.13			0.24			0.06
1st quartile		0	–		0	–		0	–
2nd quartile		−0.10 (−0.22 to 0.02)	0.104		−0.09 (−0.21 to 0.02)	0.117		−0.01 (−0.17 to 0.14)	0.865
3rd quartile		−0.07 (−0.19 to 0.05)	0.233		−0.07 (−0.19 to 0.04)	0.205		−0.003 (−0.16 to 0.15)	0.964
4th quartile		−0.03 (−0.15 to 0.09)	0.662		−0.02 (−0.13 to 0.10)	0.754		−0.03 (−0.18 to 0.13)	0.739
(C) Farm type: (=896)
Only cattle	0.13	0	–	0.23	0	–	0.05	0	–
Mixed pigs/cattle		−0.03 (−0.13 to 0.08)	0.619		−0.06 (−0.16 to 0.04)	0.264		0.07 (−0.11 to 0.17)	0.659
Only pigs		−0.02 (−0.14 to 0.11)	0.786		−0.03 (−0.15 to 0.09	0.667		0.00 (−0.16 to 0.17)	0.955
(D) Farm status: (n=897)	0.14			0.23			0.06
Ex-farmers		0	–		0	–		0	–
Current farmers		−0.12 (−0.21 to −0.03)	0.006		−0.04 (−0.13 to 0.04)	0.334		−0.15 (−0.26 to −0.04)	0.009

Mutually adjusted for smoking, second hand smoking, sex, being raised on a farm, baseline BHR and follow-up BMI.
Bold shows significance p<0.05.
BHR, bronchial hyper responsiveness; BMI, body mass index; E, estimate; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity.