Cardiovascular Risk in the Lung Cancer Screening Population: A Multicenter Study Evaluating the Association Between Coronary Artery Calcification and Preventive Statin Prescription

Abstract

Objective: Coronary artery calcification (CAC) is a marker of atherosclerotic cardiovascular disease (ASCVD), the leading cause of death in individuals receiving lung cancer screening (LCS) with low-dose CT. Our purpose was to determine the proportion of the LCS population eligible for primary ASCVD preventive statin therapy by American College of Cardiology/American Heart Association guidelines, assess statin prescription rates among statin-eligible individuals, and determine associations of CAC on downstream statin prescribing within 90 days of LCS.

Methods: Individuals receiving LCS between January 1, 2016, and December 31, 2018, across three centers were retrospectively enrolled. Statin eligibility in individuals without pre-existing ASCVD was determined by 2013 American College of Cardiology/American Heart Association guidelines: (1) low-density lipoprotein ≥190 mg/dL, (2) diabetes, or (3) ASCVD risk score ≥7.5%. CAC presence and severity (mild, moderate, heavy) were extracted from LCS reports. Variation in statin prescription rates and associations between CAC and statin prescription were determined using mixed-effects logistic regression.

Results: Of 5,495 individuals receiving LCS, 31.4% (1,724 of 5,495) had pre-existing ASCVD. Of the remaining 3,771 individuals, 73.6% were statin eligible (2,777 of 3,771). However, most lacked statin prescription (60.5%, 1,681 of 2,777). CAC was associated with downstream statin prescribing (adjusted odds ratio = 2.60, 95% confidence interval: 1.12-6.02), with a higher likelihood of statin prescribing with increasing CAC severity (adjusted odds ratio = 2.21, 95% confidence interval: 1.35-3.60).

Conclusion: Although most of the LCS population is eligible for guideline-directed statin therapy, statins are underprescribed in this group. Radiologist reporting of CAC at LCS reflects a potential opportunity to raise awareness of ASCVD risk and improve preventive statin prescribing.

Keywords: Atherosclerotic cardiovascular disease; coronary artery calcification; lung cancer screening; primary prevention.

Figure 1:. Analysis diagram of statin eligibility and statin prescription status at the time of baseline LCS examination. Statin eligibility was defined by the 2013 ACC/AHA guidelines.

⁺Statin eligibility categories are not mutually exclusive. ASCVD=atherosclerotic cardiovascular disease; LCS = lung cancer screening; LDL = low-density lipoprotein.