The Effect of Continuous Positive Airway Pressure Treatment on Insulin Sensitivity in Patients with Obstructive Sleep Apnoea Syndrome and Type 2 Diabetes

Abstract

Background: The obstructive sleep apnoea syndrome (OSA) is a frequent condition, as well as type 2 diabetes mellitus. Both diseases are characterized by insulin resistance. Objectives: The aim of this study was to establish whether OSA is an independent risk factor for increased insulin resistance in diabetics. For this purpose, we tested the hypothesis that the insulin sensitivity in patients with type 2 diabetes and OSA can be improved by 2 days or 3 months of continuous positive airway pressure (CPAP) treatment. Methods: In 9 obese patients with type 2 diabetes and OSA [apnoea/hypopnoea index 43.1 ± 21.3; body mass index (BMI) 37.3 ± 5.6 kg/m²] and good glycaemic control on oral antidiabetics or on diet alone (HbA1c 6.4 ± 0.7%), the insulin sensitivity index (ISI) was established by euglycaemic hyperinsulinaemic clamp tests at baseline, after 2 days and after 3 months of effective CPAP treatment. Results: ISI was unchanged after 2 days of CPAP treatment, but was significantly improved after 3 months (4.38 ± 2.94 vs. 2.74 ± 2.25 at baseline; p = 0.021), without any significant changes in BMI. Glycaemic control was unaffected after 3 months (HbA1c 6.3 ± 0.6%; not significant). Fasting leptin levels showed no significant changes. Conclusions: These results indicate that OSA itself is an independent risk factor for insulin resistance. This effect may be explained by the elevated sympathetic activity in OSA.

Clinical Outcomes and Cost-effectiveness of Continuous Positive Airway Pressure to Manage Obstructive Sleep Apnea in Patients With Type 2 Diabetes in the U.K.

“…Regression analyses found that there was no relationship between the number of antidiabetes medication prescriptions and HbA 1c levels. These observations reinforce the findings of others that use of CPAP can reduce hypertension (35) and possibly reduce insulin resistance (18)(19)(20), leading to lower serum glucose levels and HbA 1c levels (21,22,36). However, this is the first time a study, based on the management of patients in actual clinical practice, has shown that use of CPAP leads to lower HbA 1c levels over five consecutive years compared with untreated patients.…”

“…The short-term effect of CPAP treatment on diabetes is controversial, with some studies reporting an improvement in insulin sensitivity (18)(19)(20) and a reduction in HbA 1c levels (21,22), while others have reported no effect (23).…”

Sleep Apnea and Cardiovascular Disease

“…110 -112 Vascular and other adverse effects of insulin resistance may contribute to cardiovascular disease in OSA. However, although some studies suggest that CPAP therapy may reduce insulin resistance in OSA, 113 a systematic review of 24 earlier reports, while confirming a probable independent link between SDB, glucose intolerance, and insulin resistance, also concluded that studies on the treatment of SDB with CPAP yielded inconsistent results and did not reveal an improvement in the metabolic disturbance after treatment. 114 Finally, related metabolic dysregulation such as leptin resistance and the metabolic syndrome also have been linked to OSA.…”

Obesity and Sleep Disturbance in Children

“…Лептин, синтезируемый главным образом под-кожно-жировой клетчаткой, имеет эффект подавления аппетита на уровне гипоталамуса, грелин же, напро-тив, имеет центральное действие, возбуждает аппе-тит и вызывает чувство голода [52,53]. Многократные исследования демонстрируют повышенный уровень циркулирующего лептина при СОАС и его снижение при режиме искусственной вентиляции легких посто-янным положительным давлением (СРАР-терапия) [54]. Следовательно, можно было бы предположить, что люди с СОАС должны иметь сниженный аппетит вплоть до пол-ного отказа от приема пищи.…”