0572 Impact of CPAP Therapy on HbA1c in Patients with Obstructive Sleep Apnea and Pre-Diabetes: A Preliminary Analysis

Introduction Patients with Obstructive Sleep Apnea (OSA) have higher levels of inflammatory cytokines, like tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6). Similar higher systemic inflammatory cytokines have been linked to insulin resistance, thus emphasizing possible metabolic complications of OSA. Yet, the effect of positive airway pressure (PAP) therapy on glycemic control in those with concomitant OSA and pre-diabetes i unknown. Methods We performed a retrospective cohort study analyzing data from our tertiary care sleep center in adults with OSA and concomitant prediabetes who were initiated on CPAP therapy between April 2018 to April 2021. OSA was identified using ICD-9-CM (327.23) and ICD-10code (G47.39). Prediabetes was defined as hemoglobin A1c (HbA1c) between 5.7–6.4%. Demographic data were collected including age, gender, BMI, and number of comorbidities. The data was stratified among those on medications for pre-diabetes versus those that were not on any medications for it. Our outcome of interest was the change of mean A1c after CPAP initiation. Descriptive statistics were performed, while t-test was used to assess the changes of mean A1c values before and after CPAP treatment with a statistically significant level p< 0.05 Results A total of 71 patients were included in the current analysis. The average age was 61.53 years, and 65% were female, while 44% non-Hispanic whites, 28% non-Hispanic blacks, 21% Hispanics and 6% Asians. Among those with concomitant OSA-prediabetes on medications, the mean HbA1c before CPAP initiation was 6.03% which changed to 6.63% after CPAP initiation over a mean follow up duration of 485 days (p=0.04 from one-tail t-test). Among those with concomitant OSA-prediabetes not on medications, the mean A1c before CPAP initiation was 6% which marginally had changed to 6.42% after CPAP therapy over mean follow up duration of 447 days (p=0.05 from one-tail t-test), again remaining within pre-diabetes range. Conclusion Our results show that HbA1c remain stable within pre-diabetes range in patients with concomitant OSA and pre-diabetes using CPAP therapy. Some limitations could be retrospective nature of the study, small sample size, lack of CPAP compliance data. Larger prospective studies are suggested to further investigate the effect of CPAP on progression to diabetes among these patients. Support (if any)