Evaluation of the Severity of Cardiovascular Autonomic Neuropathy in Type 1 Diabetic Patients With OSAS
Evaluation of the Severity of Cardiovascular Autonomic Neuropathy in Type 1 Diabetic Patients With OSAS
The links between obstructive sleep apnea syndrome (OSAS) and type 1 diabetes (T1D) are
 poorly studied. This study proposes to evaluate the severity of cardiovascular autonomic
 neuropathy (CAN) related to T1D in case of associated OSAS. This issue has significant
 diagnostic and therapeutic implications because of the increased cardiovascular risk in case
 of confirmed CAN in T1D patients.
Cardiovascular autonomic neuropathy (CAN) is a common complication of type 1 diabetes (T1D)
 and is associated with increased cardiovascular risk. Otherwise, some studies have found a
 high frequence of obstructive sleep apnea syndrome (OSAs) in T1D. Cardiac autonomic
 modulations are deeply altered in OSAS. The combination of T1D and OSAS could therefore
 increase the severity of CAN and worsen the cardiovascular prognosis.

 The most common method used to explore CAN is the study of heart rate variability (HRV). HRV
 is a practical, non-invasive and reproducible measure of autonomic nervous system function.
 HRV abnormalities are a predictor of hypertension and increased mortality in T1D.

 Th investigators therefore propose to explore the severity of NAC in case of OSAS associated
 with T1D, and the hypothesis is that cardiovascular damage is increased in the presence of
 these two pathologies.

 The patients included in this study will be patients with type 1 diabetes diagnosed for more
 than 5 years.

 After overnight polysomnography, cardiovascular autonomic neuropathy will be evaluated by
 different methods: study of HRV, cardiovascular autonomic reflex test (Ewing), measurements
 of urinary levels of catecholamines and measurements of sweat gland dysfunction using
 Sudoscan.

 The severity of CAN will be evaluated in T1D patients with moderate to severe OSAS (apnea
 hypopnea index (IAH) ≥15 / hour) compared to T1D patients with IAH <15 / hour.

 Furthermore, glycemic holter will describe the links between glycemic variability, sleep
 architecture and CAN. Biological oxidative stress assays will improve physiopathological
 knowledge between T1D, OSAS and CAN. Finally, a 24-hour monitoring of blood pressure will be
 performed.

 An ancillary study is planned to evaluate the evolution of markers of the autonomic nervous
 system after three months of treatment with CPAP in 15 patients with severe OSAS (AHI ≥30 /
 hour) having previously participated in the main study. Fifteen patients with IAH <30 / hour
 will also be reassessed at three months to assess the intra-individual variability of the
 HRV.
Inclusion criteria:

 -  Type 1 diabetes patients with a diabetes duration of at least 5 years

 -  Age between 18 and 60 years old.

 Exclusion criteria:

 -  OSAS treated with CPAP

 -  Chronic alcoholism

 -  Neuromuscular disease

 -  Drugs interfering with sinus variability (betablockers, antiarrhythmics, ivabradine),
 presence of pacemaker

 -  Pregant woman