1. M. Fevre-Genoulaz M.J. Lafitte S.S. Srikanta
Measuring and scoring cardiac autonomic neuropathy : a first comparison in diabetes
M. Fevre-Genoulaz
M.J. Lafitte
S.S. Srikanta

2. Aim of the study
Compare the classification of cardiac autonomic neuropathy (CAN) given by standard autonomic scoring and by a new device : the ANSiscopeTM (Dyansys) in healthy volunteers and in diabetic patients

3. Study population
21 type 2 diabetic patients (mean age=50+/-9 yrs). 4 of them had complications due to diabetes : retinopathy, and hypertension
9 non-diabetic volunteers (mean age 38 +/-9 yrs)

4. Exclusion criteria Causes of autonomic neuropathy other than diabetes
History of psychoactive drug or alcohol abuse
Cardiac arrythmia

5. Methods Each patient underwent 2 sets of tests : Autonomic tests
ANSiscopeTM autonomic dysfunction test

6. Autonomic tests RSA : respiratory sinus arrythmia Valsalva manoeuver
Ratio RR inspiration/RR expiration
Valsalva manoeuver
Ratio longest RR/shortest RR
Systolic blood pressure response to standing
Difference between SBP before and 2 min after standing.
30:15 ratio
Ratio 30th RR int./15th RR int.

7. Autonomic tests scoring
Scoring is made following description of Bellavere et al. For each test results are classified as being :
Normal = 0
Borderline = 1
Abnormal = 2
The points are added and final score is interpreted as :
0 and 1 = healthy
Between 2 and 4 = early CAN
5 and upper = advanced CAN

8. Assessment of autonomic scoring
minimum 30 minutes of testing
45 minutes of signal analysis
Complete patient participation
Trained medical team

9. Measurement with the ANSiscopeTM
This device extracts from the RR intervals (recorded with 3 leads ECG) the activity of the sympathetic and parasympathetic systems on a beat by beat basis.
Measurement of dysautonomia is expressed as a lack of coupling between both activites. Result is expressed as a percentage and a group classification.

10. Measurement conditions with the ANSiscopeTM
A recording of 572 RR intervals is needed (around 5-7 minutes)
Patient must be at rest in supine condition without external stimulation (which may activate sympathetic system).

11. Classification group The nature of the groups : aggregation of values
Values demarcating groups
-11.5 to 11.5 : healthy group
13.5 to 20 : early group
23 to : late group
51 to 100 : advanced group
healthy
early
late
advanced

12. Results 10 E 20 H Autonomic scoring ANSiscope
Number of patients / groups (H = healthy, E = Early, L = late, A = Advanced), (mean average of dysautonomia percentage +/- Std)
Autonomic scoring detected 2 groups of patients : healthy and early CAN
ANSiscopeTM detected 4 stages of CAN in the same set of patients from healthy to most advanced CAN.
If we consider in the ANSiscopeTM classification 2 groups of patients : (healthy + early) and (late + advanced), we obtain :

13. Results
Aut. scoring
ANSiscopeTM H E
H+E
L+A
9 non diabetics
80%
20%
100%
17 diabetics
76%
24%
30%
70%
4 diabetics with complications
Non diabetic and diabetic populations have the same proportion of H and E with autonomic scoring
All patients classified with L and A CAN with the ANSiscope have a mean diabetes duration of 7 yrs which predisposes them to CAN.
All diabetics patients with complications are in L + A group.
Some patients without clinical symptoms are in L+A group, these patients may be considered as being at risk to develop complications due to diabetes.

14. Conclusion
These first results suggest that the ANSiscopeTM allows to detect precociously CAN and classify patients accurately compared to autonomic scoring.
Method is simple, quick and does not require particular training, it thus represents a good tool to measure autonomic neuropathy in clinical practice.
Further studies need to be performed on larger population.