Background and aims

A large proportion of statin eligible candidates have a baseline absence of coronary artery calcium (CAC) and low 10-year atherosclerotic cardiovascular disease (ASCVD) risk. We sought to determine the proportion of statin eligible individuals who had long-term healthy arterial aging (persistent CAC = 0) and their examined 15-year ASCVD outcomes.

Methods

We included 561 statin eligible candidates from the Multi-Ethnic Study of Atherosclerosis who were not on statin therapy with CAC = 0 at Visit 1 (2000-02) and underwent a subsequent CAC scan at Visit 5 (2010-11). Adjusted Cox proportional hazards regression assessed the association between persistent CAC = 0 and ASCVD events over 15.9 years.

Results

Participants were on average 61.7 years old, 50% were women, and 43% maintained long-term CAC = 0. Individuals with an LDL-C ≥190 mg/dL (54%) and those with an ASCVD risk ≥20% (33%) had the highest and lowest proportion of persistent CAC = 0, respectively. There were 57 ASCVD events, and 15-year ASCVD event rates were low for individuals with and without healthy arterial aging (4.3 versus 8.6 per 1,000 persons-years), but the 10-year number needed to treat to prevent one ASCVD event differed by more than two fold (117 versus 54). In multivariable modeling, persistent CAC = 0 conferred a 51% lower risk of ASCVD compared to those with incident CAC (HR = 0.49, 95% CI: 0.27-0.90, p=0.02).

Conclusions

More than 40% of statin eligible individuals with baseline CAC = 0 had long-term healthy arterial aging. Statin eligible candidates with persistent CAC = 0 had a very low 15-year ASCVD risk, suggesting that statin therapy may be of limited benefit among this group of individuals.

Objectives

The purpose of this study was to identify predictors of healthy arterial aging (long-term coronary artery calcification [CAC] of 0) among individuals with metabolic syndrome (MetS) or type 2 diabetes (T2D), which may improve primary prevention strategies.

Background

Individuals with MetS or T2D have a heterogeneously increased risk of atherosclerotic cardiovascular disease and not all have a high-intermediate risk.

Methods

We included 574 participants from the MESA (Multi-Ethnic Study of Atherosclerosis) with MetS or T2D who had CAC=0 at baseline and a repeat CAC scan 10 years later. Multivariable logistic regression assessed the association of traditional and novel atherosclerotic cardiovascular disease risk factors and the MetS severity score (based on the 5 MetS criteria) with healthy arterial aging.

Results

The mean age of participants was 58.9 years, 67% were women, 422 participants had MetS, and 152 had T2D. The proportion with long-term CAC=0 was similar for MetS (42%) and T2D (44%). A younger age was the only individual low/normal traditional risk factor associated with an increased likelihood of long-term CAC=0 (odds ratio [OR]: 1.50; 95% confidence interval [CI]: 1.22 to 1.85 per 10-years younger). The strongest associations of nontraditional risk factors were observed for an absence of thoracic calcification (OR: 2.42; 95% CI: 1.24 to 4.72), absence of carotid plaque (OR: 1.81; 95% CI: 1.25 to 2.61), and among persons with a high sensitivity troponin <3 ng/ml (OR: 1.55; 95% CI: 1.01 to 2.38). In addition, persons with the lowest quartile MetS severity score had a substantially higher odds of healthy long-term CAC=0 (OR: 2.71; 95% CI: 1.27 to 5.76).

Conclusions

More than 40% of adults with MetS or T2D and baseline CAC=0 had long-term absence of CAC, which was most strongly associated with an absence of extracoronary atherosclerosis and a low MetS score. An optimal overall cardiovascular profile appears to be more important than an ideal value of any individual risk factor to maintain healthy arterial aging.