Better Glycemic Control Predicts Greater PAP Benefits in OSA
SEATTLE, WA—Positive airway pressure (PAP) improved blood pressure and sleep-related symptoms in an unselected clinical population of patients with type 2 diabetes mellitus (T2DM) and obstructive sleep apnea (OSA), but did not improve glycemic control, according to data presented at SLEEP 2015.
These results mirror previous research in a carefully selected population with well-controlled T2DM and OSA, noted Lucas M. Donovan, MD, of Beth Israel Deaconess Medical Center, Boston, MA.
More than 85% of patients with T2DM have OSA. To evaluate the effectiveness of PAP therapy on symptoms of OSA, blood pressure, and glycemic control in an unselected population of patients with T2DM with OSA, Dr. Donovan and colleagues obtained data from 121 patients who had been “started on PAP as part of a program aimed at screening T2DM patients for OSA.”
Symptoms of OSA were assessed using the Patient Reported Outcomes Information System (PROMIS), the sleep-related impairment (PROM-SRI) and sleep disturbance (PROM-SDA) short-form questionnaires, and the Epworth Sleepiness Scale (ESS).
OSA symptoms and systolic/diastolic blood pressure measurements were obtained prior to initiation of PAP and at a follow-up clinic visit at least three months after PAP was initiated. Adherence to PAP was defined as usage for ≥4 hours per night on greater than 75% of nights. HbA1C values were obtained from the electronic medical record, and glycemic control was defined as a baseline HbA1C <9.0%.
Mean age of the patients was 61.1 years and 50.4% were female. At baseline, body mass index was 34.3kg/m2; 87.6% were using hypoglycemic agents and 42.2%, insulin. A total of 94 patients had an HbA1c <9.0% and in 27, HbA1C was ≥9.0%. Among the patients, OSA was mild in 50.4%, moderate in 19.8%, and severe in 29.8%; events per hour for AHI 4% was 25.2. Mean overall PAP use was 3.5 hours per night. Among the 79 nonadherent patients, it was 2.0 hours, compared with 6.2 hours for those who were adherent.
Following PAP use, significant changes were observed at follow-up for ESS, PROM-SRI, and PROM-SDA (all P<0.0001). In addition, diastolic blood pressure decreased significantly from baseline (P=0.01).
“Those with better glycemic control at baseline tended to have greater benefits in blood pressure and sleep symptoms,” Dr. Donovan concluded.