Table 1

Clinical characteristics and measures of cardiac autonomic function

Control subjects
(n = 30)Normoalbuminuria
(n = 30)Macroalbuminuria
(n = 30)P (control subject vs. normoalbuminuria)P (normoalbuminuria vs. macroalbuminuria)
Female12 (40)12 (40)13 (43)1.00.79
Age (years)59.8 ± 9.959.8 ± 9.158.2 ± 9.90.990.52
Known diabetes duration (years)32.6 ± 12.741.4 ± 13.30.01
BMI (kg/m2)24.7 ± 3.425.6 ± 4.127.2 ± 4.20.380.15
24-h systolic blood pressure (mmHg)127 ± 13135 ± 9138 ± 110.0090.26
24-h diastolic blood pressure (mmHg)79 ± 878 ± 677 ± 50.880.48
Heart rate (bpm)61 ± 869 ± 1272 ± 120.0030.41
HbA1c (mmol/mol)35.8 ± 1.961.3 ± 8.366.3 ± 11.7<0.00010.70
HbA1c (%)5.4 ± 0.177.8 ± 0.768.2 ± 1.07<0.00010.70
LDL cholesterol (mmol/L)3.4 ± 0.72.3 ± 0.72.1 ± 0.8<0.00010.32
eGFR (mL min−1 1.73 m−2)82.8 ± 13.189.1 ± 10.462.5 ± 23.10.043<0.0001
UACR (mg/g)*6 [5–10.5]3 (3–5)121 [53–283]0.0002<0.0001
Smokers4 (13)4 (14)4 (14)0.961.0
Alcohol (beverages/week)8.5 (4–14)7 (4–18)6.5 (1–14)0.870.91
Physical activity (hours/week)5.0 ± 4.24.9 ± 5.36.1 ± 11.40.930.61
Treatment
 Antihypertensive3 (10)17 (57)30 (100)0.0001<0.0001
 RAAS inhibition3 (10)14 (47)29 (97)0.002<0.0001
 β-Blocker0 (0)1 (3)8 (27)1.00.03
 Aspirin1 (3)11 (37)19 (63)0.00120.04
 Lipid-lowering0 (0)21 (70)24 (80)<0.00010.37
 Amlodipine0 (0)4 (13)10 (33)0.110.07
Known coronary artery disease0 (0)0 (0)7 (23)0.01
MFR3.0 ± 0.793.1 ± 0.792.1 ± 0.920.74<0.0001
HRV measures
Time and frequency domains
 SDNN intervals (ms)39.4 [28.6–53.0]30.0 [20.5–49.6]18.5 [13.3–34.8]0.0570.057
 RMSSD (ms)25 [20.4–39.45]19.25 [10.1–30.9]13.0 [6.5–20.1]0.0650.21
 LF power (ms2)196.7 [78.3–308.7]73.1 [24.7–238.3]21.1 [14.6–92.5]0.0450.099
 HF power (ms2)70.9 [45.9–131.5]43.2 [12.0–87.1]]22.3 [5.3–66.0]0.0770.20
 LF/HF (ratio)2.05 [1.38–4.25]2.07 [1.34–3.52]2.06 [0.89–3.46]0.640.44
 Total power (ms2)606.1 [253.6–1,106.2]291.7 [118.6–644.5]101.9 [54.6–447.4]0.030.08
CARTs
 30-to-15 ratio (response to standing)1.24 ± 0.171.12 ± 0.111.03 ± 0.250.00020.12
 E-to-I ratio (deep breathing)1.24 ± 0.151.15 ± 0.121.12 ± 0.00.020.28
 Valsalva test ratio1.77 ± 0.411.48 ± 0.191.39 ± 0.340.00450.33
CAN
 No CAN28 (100)22 (85)13 (43)0.0470.03
 CAN0 (0)4 (15)10 (57)
123I-MIBG imagingn = 14n = 30n = 30
 Late heart-to-mediastinum ratio2.9 ± 0.392.6 ± 0.382.3 ± 0.500.010.05
Sudomotor function
 Feet (µS)69.9 ± 14.455.2 ± 24.40.008
  Sudomotor dysfunction**11 (38)18 (62)0.006
 Hands (µS)58.6 ± 17.047.5 ± 18.70.02
  Sudomotor dysfunction**8 (27)18 (62)0.006
  • Data represent total number (%), mean ± SD, or median [IQR]. CAN was defined as no CAN when no pathological CART results were detected or if only one abnormal CART result was detected and as definite if two or three abnormal CART results were detected, according to the American Diabetes Association criteria. RAAS, renin-angiotensin-aldosterone system.

  • *UAER for control subjects.

  • **We applied age- and sex-stratified electrochemical skin conduction thresholds when evaluating sudomotor dysfunction in hands and feet.