Cross-sectional mean differences (95% CIs) in baseline carotid artery atherosclerosis between the group close to and the group away from major road (the reference category)
| Atherosclerosis | Close to major roads (n=117)* | Away from major roads (n=392)* | Difference†‡ (model 1) | Difference†‡ (model 2) | Difference†‡ (model 3) | Difference†‡ (model 4) |
|---|---|---|---|---|---|---|
| CIMT (µm) | 664±125 | 673±118 | −9.37 (−35.24 to 16.49) | −12.78 (−35.32 to 9.76) | −13.76 (−36.17 to 8.64) | −8.7 (−31.15 to 13.75) |
| Plaque area (mm2) | 5.37±8.10 | 6.62±11.85 | −1.25 (−3.65 to 1.14) | −1.62 (−3.89 to 0.66) | −1.45 (−3.74 to 0.85) | −0.88 (−3.19 to 1.43) |
| Plaque number | 0.83±0.93 | 0.90±1.19 | −0.07 (−0.31 to 0.18) | −0.12 (−0.36 to 0.12) | −0.11 (−0.35 to 0.13) | −0.05 (−0.29 to 0.19) |
| Total area (mm2) | 18.6±9.0 | 20.1±13.0 | −1.45 (−4.08 to 1.18) | −1.88 (−4.3 to 0.54) | −1.73 (−4.17 to 0.71) | −1.07 (−3.51 to 1.38) |
*Data are presented as mean±SD.
†Difference of least square means between the group close to and the group away from major roads (the group away from major roads was the reference category).
‡Model 1 was a crude unadjusted model; model 2 was adjusted for age, sex and ethnicity; model 3 was further adjusted for BMI, smoking status, physical activity, education and annual household income; model 4 was additionally adjusted for systolic blood pressure, LDL-C, HDL-C, neighbourhood income levels and neighbourhood education levels.
BMI, body mass index; CIMT, carotid intima-media thickness; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol.