Intramuscular fat and glucose tolerance after spinal cord injury--a cross-sectional study.

ABSTRACT

STUDY DESIGN: Survey. OBJECTIVE: Determine intramuscular fat (IMF) in affected skeletal muscle after complete spinal cord injury using a novel analysis method and determine the correlation of IMF to plasma glucose or plasma insulin during an oral glucose tolerance test. SETTING: General community of Athens, GA, USA. METHODS: A total of 12 nonexercise-trained complete spinal cord injured (SCI) persons (10 males and two females 40+/-12 years old (mean+/-SD), range 26-71 years, and 8+/-5 years post SCI) and nine nonexercise-trained nondisabled (ND) controls 29+/-9 years old, range 23-51 years, matched for height, weight, and BMI, had T(1) magnetic resonance images of their thighs taken and underwent an oral glucose tolerance test (OGTT) after giving consent. RESULTS: Average skeletal muscle cross-sectional area (CSA) (mean+/-SD) was 58.6+/-21.6 cm(2) in spinal cord subjects and 94.1+/-32.5 cm(2) in ND subjects. Average IMF CSA was 14.5+/-6.0 cm(2) in spinal cord subjects and 4.7+/-2.5 cm(2) in nondisabled subjects, resulting in an almost four-fold difference in IMF percentage of 17.3+/-4.4% in spinal cord subjects and 4.6+/-2.6% in nondisabled subjects. The 60, 90 and 120 min plasma glucose or plasma insulin were higher in the SCI group. IMF (absolute and %) was related to the 90 or 120 min plasma glucose or plasma insulin (r(2)=0.71-0.40). CONCLUSIONS: IMF is a good predictor of plasma glucose during an OGTT and may be a contributing factor to the onset of impaired glucose tolerance and type II diabetes, especially in SCI. In addition, reports of skeletal muscle CSA should be corrected for IMF.