October 15, 2002
View Full PaperCombined Use of Computed Tomography Coronary Calcium Scores and C-Reactive Protein Levels in Predicting Cardiovascular Events in Nondiabetic Individuals
Structured PICO
Does the combined use of computed tomography coronary calcium scores and C-reactive protein levels predict cardiovascular events in asymptomatic nondiabetic individuals?
P
Population
967 asymptomatic adults without diabetes or coronary heart disease, with CRP levels ≤10 mg/L (from an initial cohort of 1461 participants)
I
Intervention
Risk stratification using computed tomography coronary calcium (CAC) scores and high-sensitivity C-reactive protein (CRP) levels
O
Outcome
Occurrence of (1) nonfatal myocardial infarction (MI) or coronary death and (2) any cardiovascular event (MI, coronary death, coronary revascularization, or stroke)composite
Both coronary calcium scores and high-sensitivity CRP levels independently predict cardiovascular events in asymptomatic nondiabetic individuals, supporting their combined use for risk stratification.
Abstract
BACKGROUND: The South Bay Heart Watch is a prospective cohort study designed to appraise the value of coronary calcium and risk factors for predicting outcomes in asymptomatic adults. Two factors that may be related to subsequent cardiovascular events are coronary calcium (CAC, a manifestation of subclinical atherosclerosis) and high-sensitivity C-reactive protein (CRP, a measure of chronic inflammation). METHODS AND RESULTS: Between December 1990 and December 1992, 1461 participants without coronary heart disease underwent baseline risk factor screening, computed tomography for CAC, and measurement of CRP. Participants were followed up for 6.4+/-1.3 years. Cox regression analyses were conducted for the 967 nondiabetics with CRP levels 142.1) and the 75th percentile for CRP (>4.05 mg/L) indicated that there was increasing risk with increasing calcium and CRP. Relative risks for the medium-calcium/low-CRP risk group to high-calcium/high-CRP risk group ranged from 1.8 to 6.1 for MI/coronary death (P=0.003) and 2.8 to 7.5 for any cardiovascular event (P<0.001). CONCLUSIONS: Participants without diabetes and those at intermediate risk may benefit from risk stratification based on high-sensitivity CRP levels and CAC, because both factors contribute independently toward the incidence of cardiovascular events.