recruitment rate lower than expected

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