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Table 3 Predictors of the extent of coronary artery calcium, as measured by log-transformed non-zero coronary artery calcium scores, in three linear regression models.

From: What does my patient's coronary artery calcium score mean? Combining information from the coronary artery calcium score with information from conventional risk factors to estimate coronary heart disease risk

Model approach Model results
Predictors Coefficients (95% CI) Corresponding percent increase in natural CAC scores* p-values Adjusted R2
Age and sex only†     
   - Age, per 10 years 0.68 (0.63 – 0.73) 97% (88 – 107%) <0.001 0.14
   - Male sex 0.72 (0.61 – 0.82) 105% (85 – 127%) <0.001  
All CHD risk factors†     
   - Age, per 10 years 0.69 (0.64 – 0.73) 99% (89 – 109%) <0.001 0.17
   - Male sex 0.73 (0.63 – 0.83) 108% (88 – 130%) <0.001  
   - Hypertension 0.23 (0.14 – 0.32) 26% (14 – 38%) <0.001  
   - Diabetes mellitus 0.48 (0.33 – 0.62) 61% (40 – 88%) <0.001  
   - High cholesterol 0.15 (0.05 – 0.24) 16% (4.8 – 28%) 0.004  
   - Smoking 0.45 (0.35 – 0.54) 56% (42 – 71%) <0.001  
Estimated 10-year risk of CHD‡, only†     
   - 10-year risk, per 5% increase 0.34 (0.31 – 0.36) 40% (36 – 44%) <0.001 0.11
  1. * – The percent increase in the natural (non-transformed) CAC score associated with each predictor is calculated by exponentiating the regression coefficient from the linear regression model (when the dependent variable is log-transformed), and subtracting 1.
  2. † – Intercepts were -0.181, -0.705, and 3.17 for each model respectively. The standard deviations of the residuals were 1.682, 1.653, and 1.707.
  3. ‡ – 10-year risk of CHD estimated according to Framingham equations [16]; for assumptions used, see Methods.
  4. CAC – Coronary artery calcium; CI – Confidence interval; CHD – Coronary heart disease.