Role of insulin resistance in heart and skeletal muscle F-18 fluorodeoxyglucose uptake in patients with non-insulin-dependent diabetes mellitus.
BACKGROUND
Altered heart and skeletal glucose usage has been reported in patients with non-insulin-dependent diabetes mellitus (NIDDM). Although elevations in plasma free fatty acid (FFA) concentrations have been implicated in reduced myocardial 18fluorine-fluoro-2-deoxy-D-glucose uptake (MFU), the specific role of whole-body insulin resistance in MFU in patients with NIDDM compared with skeletal muscle metabolism remains controversial.


OBJECTIVE
MFU and skeletal muscle 18fluorine-fluoro-2-deoxy-D-glucose uptake (SMFU) were compared with positron emission tomography and the whole-body glucose disposal rate (GDR) during hyperinsulinemic euglycemic clamping in 26 normotensive asymptomatic patients with NIDDM who were not taking medication. These factors were also compared in 12 age-matched control subjects to increase the knowledge of the influence of whole-body insulin resistance on MFU. In addition, independent factors for both SMFU and MFU were investigated.


RESULTS
GDR in control subjects (10.0 +/- 2.97 mg/min per kilogram) was significantly higher than in patients with NIDDM (4.05 +/- 2.37 mg/min per kilogram, P < .01). SMFU in patients with NIDDM (0.826 +/- 0.604 mg/min per 100 g) was significantly lower than that in control subjects (1.86 +/- 1.06 mg/min per 100 g, P < .01). MFU in patients with NIDDM (5.35 +/- 2.10 mg/min per 100 g) was also significantly lower than that of control subjects (7.05 +/- 1.66 mg/min per 100 g, P = .0182). SMFU significantly correlated with GDR (r = .727, P < .01) and FFA (r = -.52, P < .01) in patients with NIDDM. MFU also correlated with GDR (r = .778, P < .01) and FFA (r = -.72, P < .01) in patients with NIDDM. Multivariate stepwise regression analysis showed that GDR (F = 36.8) was independently related to MFU (r = .85, P < .01) whereas FFA was not (F = 1.763), where F is the value for statistical analysis of multivariate stepwise regression analysis.


CONCLUSIONS
Insulin resistance is the most essential factor for both heart and skeletal muscle FDG uptake in patients with NIDDM.
Yokoyama
I
I
Department of Cardiovascular Medicine, University of Tokyo Graduate School of Medicine, Japan. yokochan-tky@umin.u-tokyo.ac.jp
Yonekura
K
K
Ohtake
T
T
Kawamura
H
H
Matsumoto
A
A
Inoue
Y
Y
Aoyagi
T
T
Sugiura
S
S
Omata
M
M
Ohtomo
K
K
Nagai
R
R
D000328:Adult; D000368:Aged; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D014055:Tomography, Emission-Computed
D005230:Fatty Acids, Nonesterified; D007328:Insulin; D019788:Fluorodeoxyglucose F18