Intramuscular fat and associations with metabolic risk factors in the Framingham Heart Study.
OBJECTIVE
Intramuscular fat accumulates between muscle fibers or within muscle cells. We investigated the association of intramuscular fat with other ectopic fat deposits and metabolic risk factors.


RESULTS
Participants (n=2945; 50.2% women; mean age 50.8 years) from the Framingham Heart Study underwent multidetector computed tomography scanning of the abdomen. Regions of interest were placed on the left and right paraspinous muscle, and the muscle attenuation (MA) in Hounsfield units was averaged. We examined the association between MA and metabolic risk factors in multivariable models, and additionally adjusted for body mass index (BMI) and visceral adipose tissue (VAT) in separate models. MA was associated with dysglycemia, dyslipidemia, and hypertension in both sexes. In women, per standard deviation decrease in MA, there was a 1.34 (95% confidence interval, 1.10-1.64) increase in the odds of diabetes mellitus, a 1.40 (95% confidence interval, 1.22-1.61) increase in the odds of high triglycerides, and a 1.29 (95% confidence interval, 1.12-1.48) increase in the odds of hypertension. However, none of these associations persisted after adjustment for BMI or VAT. In men, we observed similar patterns for most risk factors. The exception was metabolic syndrome, which retained association in women even after adjustment for BMI and VAT, and low high density lipoprotein and high triglycerides in men, whose associations also persisted after adjustment for BMI and VAT.


CONCLUSIONS
MA was associated with metabolic risk factors, but most of these associations were lost after adjustment for BMI or VAT. However, a unique association remained for metabolic syndrome in women and lipids in men.
Boston University School of Medicine, Boston, MA, USA.
Kate E
KE
Therkelsen
Alison
A
Pedley
Elizabeth K
EK
Speliotes
Joseph M
JM
Massaro
Joanne
J
Murabito
Udo
U
Hoffmann
Caroline S
CS
Fox
D000273:Adipose Tissue / Q000000981:diagnostic imaging / Q000503:physiopathology*; D050154:Adiposity; D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000097:blood / Q000453:epidemiology* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000097:blood / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D006306:Health Surveys; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000503:physiopathology; D050152:Intra-Abdominal Fat / Q000503:physiopathology; D016014:Linear Models; D008055:Lipids / Q000097:blood; D016015:Logistic Models; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D024821:Metabolic Syndrome / Q000097:blood / Q000453:epidemiology* / Q000503:physiopathology; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D015999:Multivariate Analysis; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000503:physiopathology*; D009765:Obesity / Q000097:blood / Q000453:epidemiology / Q000503:physiopathology; D016017:Odds Ratio; D012307:Risk Factors; D055105:Waist Circumference
D001786:Blood Glucose; D008055:Lipids