Sarcopenia, obesity, and inflammation--results from the Trial of Angiotensin Converting Enzyme Inhibition and Novel Cardiovascular Risk Factors study.
BACKGROUND
Age-related body-composition changes are associated with health-related outcomes in elders. This relation may be explained by inflammation and hemostatic abnormalities.


OBJECTIVE
Our objectives were to evaluate the relation between body-composition measures [body mass index (BMI), total fat mass, and appendicular lean mass (aLM)] and C-reactive protein (CRP), interleukin 6 (IL-6), and plasminogen activator inhibitor 1 (PAI-1) and to explore the effect of obesity and sarcopenia on CRP, IL-6, and PAI-1 concentrations.


METHODS
The data are from the Trial of Angiotensin Converting Enzyme Inhibition and Novel Cardiovascular Risk Factors (TRAIN) study baseline visit (n = 286; mean age = 66.0 y). Total fat mass and aLM were assessed with a dual-energy X-ray absorptiometry scan. Linear regressions were performed between body-composition measures and CRP, IL-6, or PAI-1 concentrations. The effect of sarcopenia and obesity (defined as the percentage of fat mass) on CRP, IL-6, and PAI-1 concentrations was evaluated with the use of analyses of covariance.


RESULTS
CRP and IL-6 were positively associated with both BMI [beta = 0.027 (P = 0.03) and beta = 0.048 (P < 0.001), respectively] and total fat mass [beta = 0.049 (P < 0.001) and beta = 0.055 (P < 0.001), respectively] and were inversely associated with fat-adjusted aLM [beta = -0.629 (P = 0.002) and beta = -0.467 (P = 0.02), respectively]. PAI-1 was positively associated with both BMI (beta = 0.038, P = 0.005) and total fat mass (beta = 0.032, P = 0.007). No significant interaction was found between either obesity or sarcopenia and CRP, IL-6, and PAI-1 concentrations. Obesity remained significantly associated with high CRP and IL-6 concentrations after adjustments for sarcopenia.


CONCLUSIONS
CRP and IL-6 are positively associated with total fat mass and negatively associated with aLM. Obesity-associated inflammation may play an important role in the age-related process that leads to sarcopenia. The relation of inflammation with sarcopenia was not independent of any of the considered obesity indexes.
Cesari
Matteo
M
Department of Aging and Geriatric Research, College of Medicine, Institute on Aging, University of Florida, Gainesville, FL, USA. mcesari@aging.ufl.edu
Kritchevsky
Stephen B
SB
Baumgartner
Richard N
RN
Atkinson
Hal H
HH
Penninx
Brenda W H J
BW
Lenchik
Leon
L
Palla
Shana L
SL
Ambrosius
Walter T
WT
Tracy
Russell P
RP
Pahor
Marco
M
D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D001823:Body Composition; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis; D002318:Cardiovascular Diseases / Q000209:etiology / Q000517:prevention & control*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007249:Inflammation / Q000150:complications*; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology*; D009765:Obesity / Q000150:complications*; D017395:Plasminogen Activator Inhibitor 1 / Q000097:blood; D012307:Risk Factors
D000806:Angiotensin-Converting Enzyme Inhibitors; D015850:Interleukin-6; D017395:Plasminogen Activator Inhibitor 1; D002097:C-Reactive Protein