Introduction:
Low muscle mass and low muscle strength, the defining components of sarcopenia, are associated with increased risks of cardiovascular disease and mortality. However, little is known about the association of sarcopenia with markers of subclinical atherosclerosis, such as coronary artery calcium (CAC). We assessed the hypothesis that sarcopenia and its defining components are associated with higher CAC scores in middle-aged and older adults.
Methods:
In this cross-sectional analysis we included 2700 participants from the São Paulo site of the Brazilian Longitudinal Study of Adult Health second wave, aged ≥ 50 years, who were submitted to CAC assessment, with no previous history of coronary artery disease and stroke, and with complete data on exposure, outcome and covariates. CAC was measured by noncontrast computed tomography scans and the Agatston method was adopted to calculate CAC scores. Muscle mass was assessed by bioelectrical impedance analysis and muscle strength by handgrip strength. Sarcopenia was defined according to the Foundation for the National Institutes of Health criteria. The association of sarcopenia and its defining components with CAC score > 0 or > 100 was investigated with logistic regression. We also investigated the association of continuous appendicular lean mass standardized by body mass index and handgrip strength with CAC score > 0 and > 100. Possible confounders included sociodemographic characteristics, clinical conditions, lifestyle and laboratory parameters.
Results:
Sarcopenia was found in 1% (23 out of 2700) of participants, 23% (609 out of 2700) with low muscle mass and 2% (40 out of 2700) with low muscle strength. CAC > 0 and CAC > 100 were found in 35% (952 out of 2700) and 13% (357 out of 2700) of participants, respectively. After adjustment for sociodemographic characteristics, clinical conditions, lifestyle and laboratory parameters, low muscle mass was associated with CAC > 100 (OR = 1.37, 95%CI 1.03-1.80), but not with CAC > 0 (OR = 1.17, 95% CI = 0.94-1.46). Sarcopenia and low muscle strength were not associated with CAC scores. Additionally, continuous appendicular leans mass standardized by body mass index was associated with lower odds of CAC > 100 (OR = 0.15, 95% CI = 0.05-0.50), although it was not associated with CAC > 0. Finally, continuous handgrip strength was not associated with CAC scores.
Conclusion:
In conclusion, low muscle mass is associated with higher odds of CAC score > 100 in middle-aged and older adults.