Table 4. Association between air pollutants and components of metabolic syndrome.

	Fasting time (hours)	10-year mean PM10 OR (95%CI)	P-value	10-year mean NO2 OR (95%CI)	P-value
Impaired fasting Glycaemia (IFG;WHO)	4	1.82 (1.60, 2.08)	<0.001	1.15 (0.98, 1.34)	0.080
	8	2.27 (1.43, 3.62)	0.001	1.33 (0.98, 1.79)	0.063
Impaired fasting Glycaemia (IFG; IDF/ATP-III)	4	1.45 (1.19, 1.78)	<0.001	1.06 (0.93, 1.21)	0.388
	8	1.84 (1.30, 2.60)	0.001	1.36 (1.08, 1.72)	0.008
Low high-density lipoproteins (WHO)	4	0.95 (0.76, 1.19)	0.657	0.88 (0.76, 1.01)	0.071
	8	0.89 (0.47, 1.70)	0.735	0.76 (0.49, 1.19)	0.229
Low high-density lipoproteins (IDF/ATP-III)	4	0.99 (0.87, 1.12)	0.847	0.95 (0.87, 1.05)	0.303
	8	0.99 (0.63, 1.56)	0.982	0.86 (0.66, 1.13)	0.287
High triglycerides	4	0.90 (0.77, 1.05)	0.169	0.94 (0.85, 1.03)	0.194
	8	1.14 (0.78, 1.67)	0.494	0.94 (0.73, 1.21)	0.630
Hypertension (WHO)	4	1.12 (0.97, 1.29)	0.130	1.11 (1.01, 1.20)	0.022
Hypertension (IDF/ATP-III)	4	1.11 (0.95, 1.30)	0.172	1.12 (1.03, 1.23)	0.011
Central obesity (BMI>30kg/m2)	4	1.00 (0.83, 1.21)	0.971	1.01 (0.89, 1.14)	0.898
Central obesity a	4	1.19 (0.90, 1.58)	0.218	1.06 (0.90, 1.26)	0.465

Fully adjusted models include age, sex, educational attainment, neighbourhood socio-economic index, occupational exposure to vapours, gases, dusts and fumes, smoking status, smoked pack-years, exposure to passive smoke, consumption of fruits and raw vegetables, physical activity and body mass index (BMI). Model for obesity excludes BMI. PM₁₀: particulate matter <10μm in diameter from all sources. NO₂: nitrogen dioxide. Traffic PM₁₀ refers to dispersion models including only traffic-related emissions. OR: odds ratio. CI: confidence interval. OR values represent fold increase in odds of outcomes per 10μg/m³ of PM₁₀, NO₂, and 1μg/m³ of traffic PM₁₀ exposure. IFG defined as fasting blood glucose≥6.1mmol/L and/or diagnosis of type2diabetes. High triglycerides defined as fasting triglycerides≥1.7mmol/L or treatment for this condition. Low HDL defined by IDF and ATP-III as < 1.03 mmol/L (males), < 1.29 mmol/L (females), or treatment for this condition, and by WHO as ≤ 0.9 mmol/L (males), ≤ 1.0 mmol/L (females). Hypertension defined by IDF and ATP-III as blood pressure >130/85 mm Hg and by WHO as ≥140/90, or treatment of previously diagnosed hypertension. Participants’ study area was treated as a random effect in all models. N (4 hours fasting time) = 3684. N (8 hours fasting time) = 367.

^aCentral obesity defined using the predicted waist circumference and European cut-offs (≥94cm for males and ≥80cm for females)