Adding carotid intima-media thickness and plaque to traditional risk factors improved the AUC for 10-year CHD risk prediction from 0.742 to 0.755 (95% CI for difference 0.008-0.017).
Cohort (n=13,145)
Yes
Does adding carotid intima-media thickness and plaque presence to traditional risk factors improve coronary heart disease risk prediction in the ARIC study population?
Adding carotid intima-media thickness and plaque presence to traditional risk factors modestly improves 10-year coronary heart disease risk prediction and reclassifies approximately 23% of subjects.
Effect estimate: AUC difference (95% CI 0.008 to 0.017)
Absolute Event Rate: 0.755% vs 0.742%
OBJECTIVES: We evaluated whether carotid intima-media thickness (CIMT) and the presence or absence of plaque improved coronary heart disease (CHD) risk prediction when added to traditional risk factors (TRF). BACKGROUND: Traditional CHD risk prediction schemes need further improvement as the majority of the CHD events occur in the "low" and "intermediate" risk groups. On an ultrasound scan, CIMT and presence of plaque are associated with CHD, and therefore could potentially help improve CHD risk prediction. METHODS: Risk prediction models (overall, and in men and women) considered included TRF only, TRF plus CIMT, TRF plus plaque, and TRF plus CIMT plus plaque. Model predictivity was determined by calculating the area under the receiver-operating characteristic curve (AUC) adjusted for optimism. Cox proportional hazards models were used to estimate 10-year CHD risk for each model, and the number of subjects reclassified was determined. Observed events were compared with expected events, and the net reclassification index was calculated. RESULTS: Of 13,145 eligible subjects (5,682 men, 7,463 women), approximately 23% were reclassified by adding CIMT plus plaque information. Overall, the CIMT plus TRF plus plaque model provided the most improvement in AUC, which increased from 0.742 (TRF only) to 0.755 (95% confidence interval for the difference in adjusted AUC: 0.008 to 0.017) in the overall sample. Similarly, the CIMT plus TRF plus plaque model had the best net reclassification index of 9.9% in the overall population. Sex-specific analyses are presented in the manuscript. CONCLUSIONS: Adding plaque and CIMT to TRF improves CHD risk prediction in the ARIC (Atherosclerosis Risk In Communities) study.
Nambi et al. (2010) conducted a cohort in Coronary Heart Disease (CHD) risk (n=13,145). Carotid intima-media thickness (CIMT) and plaque assessment vs. Traditional risk factors (TRF) alone was evaluated on Area under the receiver-operating characteristic curve (AUC) for CHD risk prediction (AUC difference, 95% CI 0.008 to 0.017). Adding carotid intima-media thickness and plaque to traditional risk factors improved the AUC for 10-year CHD risk prediction from 0.742 to 0.755 (95% CI for difference 0.008-0.017).