Null association between abdominal muscle and calcified atherosclerosis in community-living persons without clinical cardiovascular disease: The multi-ethnic study of atherosclerosis

Objective Lean muscle loss has been hypothesized to explain J-shaped relationships of body mass index (BMI) with cardiovascular disease (CVD), yet associations of muscle mass with CVD are largely unknown. We hypothesized that low abdominal lean muscle area would be associated with greater calcified atherosclerosis, independent of other CVD risk factors. Materials/Methods We investigated 1020 participants from the Multi-Ethnic Study of Atherosclerosis who were free of clinical CVD. Computed tomography (CT) scans at the 4th and 5th lumbar disk space were used to estimate abdominal lean muscle area. Chest and abdominal CT scans were used to assess coronary artery calcification(CAC), thoracic aortic calcification (TAC), and abdominal aortic calcification (AAC). Results The mean age was 64 ± 10 years, 48% were female, and mean BMI was 28 ± 5 kg/m². In models adjusted for demographics, physical activity, caloric intake, and traditional CVD risk factors, there was no inverse association of abdominal muscle mass with CAC (prevalence ratio [PR] 1.02 [95% CI 0.95,1.10]), TAC (PR 1.13 [95%CI 0.92, 1.39]) or AAC (PR 0.99 [95%CI 0.94, 1.04]) prevalence. Similarly, there was no significant inverse relationship between abdominal lean muscle area and CAC, TAC, and AAC severity. Conclusion In community-living individuals without clinical CVD, greater abdominal lean muscle area is not associated with less calcified atherosclerosis.