Table 2– Lung function by CHRNA3 rs1051730 genotype in The Copenhagen General Population Study

	Ever-smokers^#					p-value genotype and cumulative TC	Never-smokers^ƒ				p-value genotype and smoking status
	Noncarriers^¶	Heterozygotes⁺	Homozygotes^§	p-value trend	p-value cumulative TC	p-value genotype and cumulative TC	Noncarriers^¶	Heterozygotes⁺	Homozygotes^§	p-value trend	p-value genotype and smoking status
Participants n	14754	14337	3422				8967	9070	2237
FEV₁ % pred	96.5 (85.2–106.3)	95.3 (84.2–105.5)	94.1 (82.7–105.1)	<0.001	<0.001	0.11	100.3 (91.3–109.5)	100.2 (90.7–109.3)	100.0 (90.9–110.0)	0.46	<0.001
FVC % pred	98.3 (88.1–108.0)	97.5 (87.5–107.4)	97.1 (86.4–107.0)	<0.001	0.006	0.39	99.9 (91.1–109.2)	99.8 (90.7–108.9)	99.7 (91.0–108.9)	0.20	0.15
FEV₁/FVC	0.777 (0.725–0.818)	0.773 (0.723–0.817)	0.770 (0.714–0.815)	<0.001	0.02	0.02	0.799 (0.758–0.837)	0.801 (0.756–0.838)	0.801 (0.760–0.840)	0.09	<0.001

Data are presented as median (interquartile range), unless otherwise stated. p-values for trends were calculated with genotypes coded 0, 1 and 2. p-values adjusted for cumulative tobacco consumption (TC) were calculated by multiple regression. p-values for interaction between genotype, cumulative TC and smoking status were calculated by two-way ANOVA. The total number of participants does not sum to 57657 because we lacked spirometry information on some participants (2079 ever-smokers and 1201 never-smokers). FEV₁: forced expiratory volume in 1 s; % pred: % predicted; FVC: forced vital capacity. ^#: n=32513; ^¶: CC genotype; ⁺: CT genotype; ^§: TT genotype; ^ƒ: n=20274.