Table 3

Determinants of HRV, n = 397

VariableSDNN (ms)*RMSSD (ms)*PNN50 (%)*LF:HF Ratio
EstimateP valueEstimateP valueEstimateP valueEstimateP value
Intercept5.56<0.00015.82<0.0001546.2<0.0001−1.900.0001
Time-weighted HbA1c−0.08<0.0001−0.12<0.0001−19.4<0.00010.060.0166
Age (years)−0.030.0131−0.040.0100−7.10.00240.030.0920
Smoking in the past month0.020.7675−0.060.5028−6.00.66710.290.0162
Male0.070.18780.020.8384−2.30.84500.210.0420
Race-ethnicity
 Non-Hispanic black0.140.05780.370.000555.10.0007−0.450.0012
 Hispanic−0.020.72430.050.583910.20.5016−0.110.3907
 Other0.120.30130.190.249128.40.2661−0.040.8568
BMI (kg/m2)−0.010.0006−0.010.0026−1.950.00480.020.0013
Model R20.14<0.00010.16<0.00010.17<0.00010.11<0.0001
  • The full model includes a measure of glycemic control (time-weighted HbA1c), sex (referent group = Female), race-ethnicity (referent group = non-Hispanic white), smoking in the past month (referent group = No), and age and BMI at the time of the HRV assessment. Parameter estimates for each covariate included in the model and the full model R2 are given.

  • * Lower = worse.

  • Higher = worse.