Selective contribution of waist circumference reduction on the improvement of sleep-disordered breathing in patients hospitalized with type 2 diabetes mellitus.

OBJECTIVE

Sleep-disordered breathing (SDB) is a potential risk factor for cardiac sudden death. Recent studies have reported that patients with type 2 diabetes mellitus (T2DM) frequently suffer from SDB. Although the roles of hyperglycemia, disturbances of the autonomic nervous system and obesity have been postulated, the factors related to SDB in T2DM, especially those related to improvement of SDB remain unknown. We investigated the significance of waist circumference (WC), representing excess visceral fat, body mass index (BMI), glycemic control and other clinical parameters on SDB in T2DM.

METHODS AND SUBJECTS

Forty inpatients received treatment for T2DM. Overnight cardiorespiratory monitoring and laboratory tests were conducted before and after treatment of T2DM.

RESULTS

The apnea-hypopnea index (AHI) at admission correlated positively with BMI, neck circumference, WC, and systolic and diastolic blood pressures, but not with Log 1,5-anhydro-D-glucitol (1,5-AG) and presence or absence of diabetic neuropathy. Stepwise multiple regression analysis identified BMI and WC as significant determinants of AHI. After 2 or 3 weeks of glucose-lowering therapy, hyperglycemia was controlled and significant reductions in AHI, BMI, WC, 1,5-AG, leptin, high-sensitivity C-reactive protein (hs-CRP), and an oxidative stress marker, thiobarbituric acid reactive substances (TBARS) were observed. The fall in AHI correlated significantly with changes in WC independent of BMI, 1,5-AG, leptin, hs-CRP, and TBARS.

CONCLUSION

Our results demonstrated that reduction of WC correlated with improvement in SDB independent of glycemic control in T2DM, and that abdominal obesity might be a target for the treatment of SDB and prevention of potential cardiovascular diseases in T2DM.