OBSTRUCTIVE SLEEP-APNEA IN OBESE NONINSULIN-DEPENDENT DIABETIC-PATIENTS - EFFECT OF CONTINUOUS POSITIVE AIRWAY PRESSURE TREATMENT ON INSULIN RESPONSIVENESS

Patients with noninsulin-dependent diabetes mellitus (NIDDM) ace often obese and frequently complain of tiredness. These features are also c haracteristically seen in patients with obstructive sleep apnea (OSA). Therefore, it was the aim of this study to assess the prevalence of O SA among a group of obese NIDDM patients who have some clinical featur es of OSA. The effect of reversal of OSA by nasal continuous positive airway pressure (CPAP) treatment on insulin responsiveness was also in vestigated. From a population of 179 NIDDM patients with a body mass i ndex (BMI) greater than 35 kg/m(2), we performed ambulatory sleep moni toring on 31 (15 males and 16 females) who admitted to either heavy sn oring or excessive sleepiness. Results were reviewed by a sleep physic ian blinded to the clinical status of the patients, and 22 (70%) were found to have moderate or severe OSA, with mean oxygen desaturation in dexes of 10.3 +/- 5.3 and 30.7 +/- 13.2 episodes/h, respectively. A su bgroup of 10 patients (seven males and three females) with a mean BMI of 42.7 +/- 4.3 kg/m(2) was treated with nightly CPAP for 4 months. Th ese subjects all had significant OSA, with frequent obstructive apneas (mean, 47 +/- 31.6 episodes/h) and oxygen desaturation (mean minimum O-2 saturation, 74 +/- 9.5%), as determined by polysomnography. One pa tient was excluded from analysis because of infrequent use of CPAP. In sulin responsiveness in terms of glucose disposal measured by hyperins ulinemic euglycemic clamps improved from 11.4 +/- 6.2 to 15.1 +/- 4.6 mu mol/kg.min (P < 0.05) during CRAP treatment. These results indicate that OSA occurs commonly in obese NIDDM patients with excessive sleep iness or heavy snoring. Treatment of their OSA may improve insulin res ponsiveness.