Association between arterial hypertension and impaired glucose tolerance (IGT) in obstructive sleep apnoea (OSA) patients

Obstructive sleep apnoea is a risk factor of cardiovascular and metabolic disturbances. The aim of this study was to assess relationship between IGT and AHI, obesity and cardiovascular diseases in OSA subjects. We studied 255 OSA pts [195 males (76.5%) and 60 females (23.5%), mean: age – 56.8±10.7 years, AHI – 42.3±20.5, BMI – 33.1±5.5 kg/m 2 , SaO 2 – 91.7±4.7%, T90-19.1±25.4%]. Impaired glucose tolerance (IGT) [plasma level ≥ 140 mg% after 2 hours of administration 75 g glucose in oral glucose tolerance test (OGTT)] was found in 69 subjects (27.1%). In 11 patients (4.3%) OGTT confirmed diabetes (glucose ≥ 200 mg%). Comparison of OSA patients with- and without IGT is shown in the table. Variable Normal OGTT (186pts) IGT (69 pts) p AHI (n/h) 41.4±20.5 44.8±20.7 NS BMI (kg/m 2 ) 32.7±5.8 34±4.7 NS Age (years) 55.9±11.1 59.3±9.2 NS Mean SaO2 (%) 91.9±4.7 91.3±4.6 NS T90 (%) 18.3±25.3 21.2±25.9 NS Fasting glucose (mg%) 89.1±9.2 100.8±17.8 <0.0001 HbA1c (%) 5.9±0.6 6.3±0.5 0.0008 Arterial Hypertension (n/%) 127 (68.3%) 59 (85.5%) 0.006 COPD (n/%) 18 (9.7%) 4 (5.8%) NS Heart failure (n/%) 11 (5.9%) 3 (4.3%) NS Atrial fibrillation (n/%) 13 (7%) 5 (7.2%) NS Coronary artery disease (n/%) 31 (16.7%) 12 (17.4%) NS Conclusions: Prevalence of impaired glucose tolerance in OSA subjects was high (more than 25%). IGT in OSA pts was related to higher incidence of arterial hypertension, elevated plasma fasting glucose and HbA1c concentration. There were no any significant correlations between AHI, BMI, overnight desaturation or other diseases and results of OGTT.