Older individuals with certain negative risk markers have a very low risk of atherosclerotic cardiovascular disease, raising the possibility that some could forgo preventive treatment even if it’s indicated by current standards of risk assessment.
Low levels of coronary artery calcification (CAC), low galectin-3 levels, and absence of carotid plaque were all linked to a lower likelihood of disease than might be expected based on traditional risk assessment, according to the authors of analysis of a large, contemporary cohort of elderly individuals published in the Journal of the American College of Cardiology.
“Our results hold the potential to markedly improve statin allocation in elderly individuals by de-escalating or even withholding preventive therapy in elderly individuals at truly low atherosclerotic cardiovascular disease risk despite advancing age,“ wrote Martin Bødtker Mortensen, MD, PhD, of Aarhus (Denmark) University Hospital.
Most elderly individuals now qualify for lifelong preventive statin treatment, based on the broader indication for treatment in recent guidelines, and the substantial impact that age has when risk is being calculated, Dr. Mortensen and coauthors said in their report.
“Because frailty, comorbidity, and polypharmacy are increasing concerns in elderly individuals and have been proposed to increase the risk for adverse effects, the appropriateness of treating almost all elderly individuals is questionable,” they said in the report.
In their study, Dr. Mortensen and colleagues evaluated a set of 13 biomarkers or imaging tests that they though had potential to “downgrade” risk of coronary heart disease (CHD) and cardiovascular disease (CVD). They based their analysis on 5,805 patients in the BioImage Study, a prospective cohort study of elderly men and women with no atherosclerotic cardiovascular disease at the time of enrollment in 2008 and 2009. The mean age at the time of enrollment was 69 years, and the mean follow-up in this analysis was 2.7 years.
The overall rate of CHD was 6.1 per 1,000 person-years, though looking at negative risk markers, the event rate was just 0.9 for individuals with CAC of 0 and also 0.9 for those with a CAC of 10 or less, followed by 1.7 for absence of carotid plaque, and 2.6 for galectin-3 in the bottom 25th percentile, according to Dr. Mortensen and coinvestigators. Similarly, the rate of CVD was 9.2 per 1,000 person-years overall, and just 3.2 for a CAC of 0, 2.8 for a CAC of 10 or lower, 4.4 for no carotid plaque, and 4.0 for low galectin-3.
Results were less impressive for other negative risk markers, including normal ankle-brachial index (ABI) test, lack of family history, and low levels of circulating biomarkers such as high-sensitivity C-reactive protein and lipoprotein (a).
Investigators also calculated diagnostic likelihood ratios (DLR), a measure they said assesses the value of performing a diagnostic test, with values lower than 1 indicating a specific marker has value for downgrading risk.
Zero or low CAC exerted the greatest downward change in pre- to post-test risk, according to the investigators, with a multivariable-adjusted DLR of 0.20 for CHD, translating into an 80% relative risk reduction. Similarly, the adjusted DLRs for zero or low CAC for CVD were 0.48 and 0.41, respectively, translating into a 59% risk reduction.
Low galectin-3 also resulted in significant downward change in that pre- to post-test risk, investigators added.
The BioImage Study was funded by Abbott, AstraZeneca, Merck, Philips, and Takeda. Dr. Mortensen had no disclosures related to the present analysis. Coauthors provided disclosures related to G3 Pharmaceuticals, Abbott Laboratories, AstraZeneca, Bayer, Bristol-Myers Squibb, CSL Behring, Eli Lilly/DSI, Medtronic, Novartis Pharmaceuticals, OrbusNeich, and PLC/Renal Guard, among others.
SOURCE: Mortensen MB et al. J Am Coll Cardiol. 2019 Jul 1. doi: 10.1016/j.jacc.2019.04.049.