Table 4

Associations between occupational exposures and airway obstruction in the LifeLines and Vlagtwedde-Vlaardingen cohorts

	LifeLines						Vlagtwedde-Vlaardingen
Exposure*	Mild obstruction (FEV₁/FVC<70%)			Moderate/severe obstruction†			Mild obstruction (FEV₁/IVC<70%)			Moderate/severe obstruction†
Exposure*	OR (95% CI)	N‡	p Value	OR (95% CI)	N‡	p Value	OR (95% CI)	N‡	p Value	OR (95% CI)	N‡	p Value
VGDF
Non-exposed	Ref	917		Ref	233		Ref	196		Ref	76
Low	1.08 (0.96 to 1.22)	578	0.199	1.05 (0.84 to 1.31)	145	0.662	1.22 (0.95 to 1.59)	167	0.124	1.82 (1.27 to 2.60)	89	0.001
High	1.41 (1.16 to 1.70)	259	<0.001	1.39 (1.00 to 1.92)	80	0.047	1.29 (0.95 to 1.74)	276	0.101	1.85 (1.23 to 2.79)	149	0.003
Gases/fumes
Non-exposed	Ref	985		Ref	251		Ref	227		Ref	97
Low	1.10 (0.98 to 1.24)	631	0.116	1.03 (0.83 to 1.28)	164	0.787	1.11 (0.87 to 1.42)	334	0.401	1.45 (1.04 to 2.01)	182	0.028
High	1.44 (1.16 to 1.80)	138	0.001	1.47 (1.02 to 2.11)	43	0.039	1.32 (0.92 to 1.89)	78	0.130	1.55 (0.95 to 2.53)	35	0.081
Mineral dust
Non-exposed	Ref	1317		Ref	328		Ref	348		Ref	165
Low	1.19 (1.03 to 1.37)	331	0.018	1.22 (0.95 to 1.56)	91	0.128	1.16 (0.87 to 1.54)	104	0.318	1.29 (0.88 to 1.90)	50	0.199
High	1.46 (1.11 to 1.92)	106	0.007	1.76 (1.15 to 2.72)	39	0.010	1.10 (0.76 to 1.58)	187	0.619	0.99 (0.61 to 1.61)	99	0.972
Biological dust
Non-exposed	Ref	1196		Ref	314		Ref	324		Ref	141
Low	1.04 (0.92 to 1.18)	481	0.502	0.99 (0.79 to 1.24)	121	0.916	1.34 (1.04 to 1.73)	243	0.022	1.74 (1.24 to 2.43)	137	0.001
High	0.91 (0.66 to 1.25)	77	0.550	0.77 (0.45 to 1.33)	23	0.345	1.25 (0.84 to 1.84)	72	0.271	1.54 (0.92 to 2.55)	36	0.098
All pesticides
Non-exposed	Ref	1667		Ref	428		Ref	478		Ref	227
Low	0.83 (0.60 to 1.14)	59	0.241	1.15 (0.69 to 1.93)	20	0.595	1.33 (0.87 to 2.01)	52	0.185	1.08 (0.61 to 1.90)	23	0.791
High	1.28 (0.79 to 2.09)	28	0.322	1.95 (0.92 to 4.13)	10	0.083	1.48 (1.04 to 2.10)	109	0.029	1.78 (1.14 to 2.79)	64	0.011
Herbicides
Non-exposed	Ref	1711		Ref	444		Ref	511		Ref	241
Low	1.04 (0.65 to 1.67)	27	0.872	1.11 (0.51 to 2.45)	8	0.791	1.29 (0.85 to 1.98)	50	0.235	1.60 (0.93 to 2.76)	28	0.090
High	2.11 (1.03 to 4.30)	16	0.040	3.56 (1.28 to 9.88)	6	0.015	1.36 (0.93 to 2.00)	78	0.112	1.66 (1.02 to 2.69)	45	0.040
Insecticides
Non-exposed	Ref	1675		Ref	430		Ref	494		Ref	237
Low	0.81 (0.58 to 1.15)	51	0.241	1.21 (0.70 to 2.09)	18	0.497	1.04 (0.64; 1.70)	36	0.867	0.66 (0.33 to 1.33)	13	0.249
High	1.32 (0.81 to 2.16)	28	0.268	2.05 (0.96 to 4.35)	10	0.062	1.39 (0.98 to 1.98)	109	0.067	1.62 (1.04 to 2.52)	64	0.033

Statistically significant associations are depicted in bold.
Associations between occupational exposures (no/low/high) and mild (prebronchodilator FEV₁/FVC<70%) and moderate/severe airway obstruction using logistic regression adjusted for sex, age, height, weight, ever smoking (no/yes) and (log) packyears smoked in the LifeLines and Vlagtwedde-Vlaardingen cohorts. The analyses with VGDF, gases, fumes, mineral dust and biological dust were additionally adjusted for pesticide exposure, whereas the analyses with pesticides, herbicides and insecticides were additionally adjusted for VGDF exposure.
*Occupational exposures (no/low/high) were estimated based on job title and function using the ALOHA+ job exposure matrix. Non-exposed subjects were assigned as reference category (Ref).
†Moderate/severe airway obstruction=prebronchodilator FEV₁/FVC<70% and FEV₁<80%, without obstruction=prebronchodilator FEV₁/FVC≥70% and FEV₁≥80%. Subjects with mild obstruction (prebronchodilator FEV₁/FVC<70% and FEV₁≥80%predicted) or prebronchodilator FEV₁/FVC≥70% and FEV₁<80% predicted were excluded from this analysis (LifeLines n=1517 (13%) and Vlagtwedde-Vlaardingen n=436 (18%)). For Vlagtwedde-Vlaardingen: FEV₁/IVC instead of FEV₁/FVC.
‡Number of subjects with obstruction.
VGDF, vapours, gases, dust and fumes.