Increased skeletal muscle phosphocreatine recovery after sub-maximal exercise is associated with increased carotid intima-media thickness.

ABSTRACT

BACKGROUND: The association between skeletal muscle mitochondrial function and CVD risk in healthy subjects is unknown. METHODS: Forty subjects were evaluated for CVD risk with lipid profile, oral glucose tolerance test and measurement of carotid intima-media thickness (cIMT). Skeletal muscle mitochondrial function was determined by phosphocreatine recovery after sub-maximal exercise with (31)Phosphorous-MRS and represented as τPCr. RESULTS: τPCr was positively associated with age (r=+0.41; P=0.009) and cIMT (r=+0.50; P=0.001) on univariate analyses. In multivariate regression analysis controlling for age, the association between τPCr and cIMT remained significant (ß=0.003; P=0.03). This association remained significant after controlling for traditional risk factors for CVD including age, gender, tobacco use, BMI, blood pressure, cholesterol and fasting glucose in a combined model (ß=0.003; P=0.04; R(2)=0.53; P=0.008 for overall model). CONCLUSIONS: These data suggest a novel association between skeletal muscle τPCr and increased cIMT, independent of age or traditional CVD risk factors.