Table 3. Linear regression coefficients of SHS exposure (independent variable) and covariates for composite carotid artery IMT (dependent variable).
| Independent variable | Whites | Blacks | Total | |||
|---|---|---|---|---|---|---|
| β (95% CI) | P-value | β (95% CI) | P-value | β (95% CI) | P-value | |
| Black race | --- | --- | --- | --- | 69.5 (32.7, 106.3) | <0.001 |
| Female gender | -52.1 (-84.4, -19.8) | 0.002 | -4.8 (-74.2, 64.6) | 0.892 | -46.5 (-76.9, -16.1) | 0.003 |
| Age | 8.2 (4.7, 11.7) | <0.001 | 11.5 (5.6, 17.4) | <0.001 | 8.8 (5.7, 11.9) | <0.001 |
| Education | -14.5 (-43.7, 14.7) | 0.331 | -5.2 (-65.4, 55.0) | 0.865 | -10.2 (-36.9, 16.5) | 0.453 |
| Income | 8.9 (-9.5, 27.3) | 0.348 | -10.4 (-36.9, 16.1) | 0.444 | 0.8 (-14.3, 15.9) | 0.921 |
| BMI | 1.1 (-1.6, 3.8) | 0.411 | -1.3 (-5.0, 2.4) | 0.492 | 0.2 (-2.0, 2.4) | 0.827 |
| Systolic BP | 2.5 (0.9, 4.1) | 0.002 | 0.4 (-1.2, 2.0) | 0.587 | 1.7 (0.5, 2.9) | 0.002 |
| LDL-C | 0.6 (0.2, 1.0) | 0.008 | 0.1 (-0.9, 1.1) | 0.853 | 0.4 (0.01, 0.8) | 0.048 |
| TG/HDL-C | 1.3, (-4.2, 6.8) | 0.638 | 33.7 (23.1, 44.3) | <0.001 | 9.5 (4.6, 14.4) | <0.001 |
| SHS exposurea | 38.9 (7.0, 70.8) | 0.017 | 81.2 (25.7, 136.7) | 0.005 | 53.1 (25.1, 81.1) | <0.001 |
a
SHS exposure was coded as: 0=no exposure, 1=exposure in childhood, adulthood or both
SHS=secondhand smoke; IMT=intima-media thickness (μm); BMI=body mass index; BP=blood pressure; L(H)DL-C=low- (high-) density lipoprotein cholesterol; TG=triglycerides
β (95% CI) = unstandardized regression coefficients (95% confidence interval)