FAT-BONE INTERACTION MAY RESULT IN SUBCLINICAL STEATO-OSTEOMYELITIS AND DECREASED BONE MINERAL CONTENT IN AFRICAN AMERICAN MEN WITH METABOLIC SYNDROME

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 199-233-Bone Biology
Basic/Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-228
Vanessa Arguello*1, Buvana Manickam2, Arfana Akbar3, Hiba Mohiuddin2, Yuval Eisenberg2 and Elena Barengolts4
1University of Illinois at Chicago-ACMC, Oaklawn, IL, 2University of Illinois at Chicago, College of Medicine, Chicago, IL, 3Jesse Brown VAMC, Chicago, IL, 4University of Illinois, College of Medicine, Chicago, IL
INTRODUCTION: Data on the association of the metabolic syndrome (MetS) with bone mineral density (BMD) and femoral fracture risk in men is inconsistent showing either a high (1) or low (2) fracture risk. Previous studies suggest that obesity is associated with higher BMD but chronic conditions including T2DM, chronic kidney disease, and depression are associated with an increased fracture risk.  A lower risk of fracture has also been seen in a group of older men with MetS and hypertriglyceridemia.

OBJECTIVE: To explore the interaction between femur bone mineral content (BMC) and adiposity in African American men (AAM) with MetS and a high burden of chronic disease.

METHODS: AAM were recruited from an inner city Veterans Affairs medical center as part of an ongoing clinical trial evaluating pre-diabetes risk factors. Chronic disease burden was evaluated by Charlson comorbidity index. MetS was defined by AHA/NCEP-ATP III criteria. Body composition was evaluated by DXA. Several parameters were used to represent femur BMD because body composition did not provide direct measurement of femur BMD. These parameters included gynoid BMC and BMC adjusted for total gynoid tissue mass (%-Gyn-BMC = Gyn-BMC/total Gyn tissue x 100) as well as Leg-BMC and Leg-BMC adjusted for total leg tissue (%-Leg-BMC = Leg-BMC/total leg tissue x 100). Android fat was used to represent amount of visceral adiposity.

RESULTS: In the entire group, chronic conditions were highly prevalent: hypertension 68%, hyperlipidemia 54.5%, psychiatric problems including PTSD 72.5%, and cancer 13%. The Gyn-BMC was higher in MetS+ vs. MetS- but the difference disappeared after adjusting for total gynoid tissue mass. Conversely, there was no difference in Leg-BMC between Met- and MetS+ groups. After adjusting for total leg tissue, Leg-BMC in MetS+ appeared significantly lower than that of MetS- group. There was a higher amount of fat in both gynoid and leg regions in MetS+ vs. MetS- group. Correlation analysis of the entire group showed significant positive association between Gyn-BMC and triglycerides (r = 0.36, p<0.05) and both were predictive of the lower fracture risk reported in previous studies (2). A negative association was seen between %-Gyn-BMC and Android-Fat (r = -0.42, p<0.05) suggesting android fat may be interacting with BMC.
CONCLUSION: Our results show decreased femur BMC in AAM with MetS compared to men without MetS. There is also a negative association between android fat and %-Gyn-BMC. The collection of findings suggests BMC may be affected by systemic and local inflammation (represented by android and regional fat, respectively). Furthermore, this data suggests that fat-bone interaction results in variable extent of subclinical steato-osteomyelitis and subsequent reduction of bone mineral. This may in part explain the contradictory results from previous studies on the risk of femoral fractures in patients with MetS.

(1) Von Muhlen D, Safii S, Jassal SK, Svartberg J, Barrett-Connor E. Associations between the metabolic syndrome and bone health in older men and women: the Rancho Bernardo Study. Osteoporos Int. 2007;18(10):1337–44.(2) Szulc P, Varennes A, Delmas PD, Goudable J, Chapurlat R. Men with metabolic syndrome have lower bone mineral density but lower fracture risk—the MINOS study. J Bone Miner Res. 2010;25(6):1446–54.

Nothing to Disclose: VA, BM, AA, HM, YE, EB

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm