title: Lower extremity fat mass is associated with insulin resistance in overweight and obese individuals: the CARDIA study.
abstract: Lower extremity fat mass (LEFM) has been shown to be favorably associated with glucose metabolism. However, it is not clear whether this relationship is similar across varying levels of obesity. We hypothesized that lower amounts of LEFM is associated with higher insulin resistance (IR) and this association may vary according to weight status. Participants with available measures were examined from the Coronary Artery Risk Development in Young Adults study (CARDIA), a multi-center longitudinal study of the etiology of atherosclerosis in black and white men and women aged 38-50 years old in 2005-2006 (n = 1,579). The homeostasis model assessment of IR (HOMA(IR)) was calculated to estimate IR, regional adiposity was measured using dual energy X-ray absorptiometry (DXA), and weight status was defined according to BMI categories. Obese and overweight participants exhibited higher IR, total fat mass (FM), trunk FM (TFM), and LEFM compared to normal weight participants. After controlling for age, height, race, study center, education, smoking, and cardiorespiratory fitness (CRF), greater LEFM was significantly associated with higher IR only in normal weight men and women. Further adjustment for TFM revealed that lower LEFM was significantly associated with higher IR in overweight and obese men and women and the positive association in normal weight individuals was attenuated. These results suggest that excess adiposity in the lower extremities may attenuate the metabolic risk observed at a given level of abdominal adiposity in overweight and obese individuals. Weight status presents additional complexity since the metabolic influence of adipose tissue may not be homogenous across anatomic regions or level of obesity.
authors: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA. c-shay@northwestern.edu
authors: Christina M
authors: CM
authors: Shay
authors: Mercedes R
authors: MR
authors: Carnethon
authors: Timothy R
authors: TR
authors: Church
authors: Arlene L
authors: AL
authors: Hankinson
authors: Cheeling
authors: C
authors: Chan
authors: David R
authors: DR
authors: Jacobs
authors: Cora E
authors: CE
authors: Lewis
authors: Pamela J
authors: PJ
authors: Schreiner
authors: Barbara
authors: B
authors: Sternfeld
authors: Stephen
authors: S
authors: Sidney
references: Diabetes Care. 2000 Jan;23(1):57-63
references: 10857969
references: Int J Obes Relat Metab Disord. 2004 Mar;28(3):402-9
references: 14724659
references: Scand J Clin Lab Invest. 2008;68(3):204-11
references: 18446527
references: Mol Med. 2008 Nov-Dec;14(11-12):741-51
references: 19009016
references: Diabetes. 2007 Aug;56(8):2142-7
references: 17536063
references: Am J Clin Nutr. 2001 Sep;74(3):315-21
references: 11522554
references: Metabolism. 1991 Sep;40(9):990-6
references: 1895966
references: Am J Physiol. 1999 Dec;277(6):E1130-41
references: 10600804
references: Arch Intern Med. 2005 Apr 11;165(7):777-83
references: 15824297
references: Diabetologia. 2000 Dec;43(12):1498-506
references: 11151758
references: Ann Med. 1995 Aug;27(4):435-8
references: 8519504
references: J Clin Endocrinol Metab. 2005 Aug;90(8):4573-8
references: 15886255
references: J Clin Densitom. 2009 Jan-Mar;12(1):84-8
references: 18990595
references: Gend Med. 2009;6 Suppl 1:60-75
references: 19318219
references: Metabolism. 2009 May;58(5):638-43
references: 19375586
references: Diabetes Care. 2000 Oct;23(10):1584-90
references: 11023155
references: Scand J Clin Lab Invest. 2009;69(4):505-11
references: 19347748
references: Am J Clin Nutr. 2003 May;77(5):1192-7
references: 12716671
references: Diabetologia. 2005 Feb;48(2):301-8
references: 15660262
references: J Clin Endocrinol Metab. 2001 May;86(5):1930-5
references: 11344187
references: Ann N Y Acad Sci. 2002 Jun;967:135-45
references: 12079843
references: Diabetologia. 2007 Mar;50(3):625-33
references: 17216279
references: Scand J Clin Lab Invest. 2010 Jul;70(4):229-36
references: 20380618
references: Med Sci Sports Exerc. 1992 Feb;24(2):177-83
references: 1549006
references: Clin Physiol. 1999 May;19(3):238-45
references: 10361614
references: Diabetologia. 1985 Jul;28(7):412-9
references: 3899825
references: Obes Res. 2002 Jul;10(7):575-84
references: 12105277
references: Aviat Space Environ Med. 1977 Feb;48(2):111-4
references: 871279
references: J Clin Epidemiol. 1988;41(11):1105-16
references: 3204420
references: Am J Clin Nutr. 2000 Apr;71(4):885-92
references: 10731493
references: Diabetes Care. 1999 Aug;22(8):1310-7
references: 10480776