Table 2

Change in Circulating Substrate Levels as a Function of IR

p Value
Diabetic
(n = 18)
CHF/IR
(n = 31)
CHF/No-IR (n = 47)IR vs. No-IRIR vs. DMNo-IR vs. DM
Glucose, mg/dl
 Rest188.56 ± 71.30113.03 ± 18.0097.63 ± 11.16<0.001<0.001<0.001
 Peak exercise183.31 ± 68.28115.26 ± 17.14108.43 ± 15.00.270<0.001<0.001
 ΔGlucose−0.69 ± 13.612.23 ± 11.1310.87 ± 10.99<0.0010.7700.005
FFA, mmol/l
 Rest0.56 ± 0.250.65 ± 0.290.60 ± 0.250.2750.3120.506
 Peak exercise0.61 ± 0.210.66 ± 0.280.75 ± 0.330.6940.5190.136
 ΔFFA0.043 ± 0.14−0.008 ± 0.160.14 ± 0.270.0300.0810.064
Insulin, μU/ml
 Rest51.83 ± 69.428.19 ± 26.026.13 ± 1.55<0.0010.626<0.001
 Peak exercise52.74 ± 68.9724.57 ± 13.068.10 ± 4.71<0.0010.297<0.001
 ΔInsulin0.91 ± 28.37−3.79 ± 20.261.91 ± 4.350.0410.7490.288
NE, nM
 Rest4.75 ± 4.903.56 ± 2.573.07 ± 1.720.5160.8820.507
 Peak exercise6.55 ± 5.344.71 ± 2.645.61 ± 3.390.3010.7901.000
 ΔNE1.79 ± 1.771.15 ± 1.262.53 ± 2.090.0040.3280.428
CRI6.06 ± 2.757.12 ± 2.578.49 ± 3.380.1750.4050.098

Values are mean ± SD.

CRI = Chronotropic Responsiveness Index; FFA = free fatty acids; NE = norepinephrine; other abbreviations as in Table 1.

  • NE levels were measured only in the first 55 patients: 6 CHF/DM, 20 CHF/IR, and 29 CHF/no IR. For all comparisons between groups, we used the Mann-Whitney U test, except as noted.

  • We used the Student t test because the variables followed a normal distribution.