B. Clinical Sleep Science and Practice II. Sleep-Related Breathing Disorders 0736 SELF-REPORTED SLEEP IN OSA PATIENTS: ROLES OF POLYSOMNOGRAPHIC MEASURES AND DEPRESSIVE SYMPTOMS Dubrovsky, B. Weingarten, J. A. Cunningham, J. Howladar, A. Chin, W. Gikashvili, L. New York-Presbyterian Brooklyn Methodist Hospital, Department of Medicine, Division of Pulmonary and Critical Care, Center for Sleep Disorders, Brooklyn, NY. Introduction: Sleep fragmentation is typical in OSA, which is commonly co-morbid with insomnia and depression. A complex interaction between these conditions may be also genderdependent. Moreover, self-report measures of sleep quality and insomnia, such as PSQI and ISI, may relate to depression symptoms more than polysomnographic sleep disturbance. The present aim is to ascertain relative contributions of polysomnographic variables and depression symptoms to PSQI and ISI in a large sample of OSA patients. The interaction between depressive symptomatology and gender in their relationships with subjective sleep is also analyzed. Methods: A total of 1,166 patients (923 women, 1136 minorities, 18-97 y.o., age M=53.1±15.2, BMI M=34.4±8.7) undergoing an overnight PSG filled out the Center for Epidemiologic Studies Depression Scale-Revised (CESDR), ISI and PSQI. ISI and PSQI were separately regressed onto age, sex and BMI, followed by PSG variables meeting p<0.1 criterion when tested individually, followed by CESDR and CESDR-by-sex interaction. SLEEP, Volume 43, Abstract Supplement, 2020 A280 Results: Mean AHI=29.6±34.7, range 0-167/hr, 72.3% of patients had AHI≥5. The PSQI final model included total sleep time (TST), sleep efficiency (SEF), WASO, PLM index, CESDR and CESDR-by-sex. Only CESDR and CESDR-by-sex were significant (p<0.001, p=0.023, respectively). Higher CESDR predicted higher PSQI in both sexes (both p<0.001), accounting for a greater portion of PSQI variance in men (R2=39%) than in women (R2=29%). The ISI final model included TST, N3%, REM%, SEF, WASO, total arousal index, AHI, PLM index, CESDR and CESDR-by-sex. Higher ISI related to lower TST (p=0.042, R2<1%), higher REM% (p=0.016, R2<1%), and higher CESDR (p<0.001, R2=42%). CESDR-by-sex was not significant. Conclusion: In this large sample, after controlling for demographic variables, PSG parameters had only minimal relationship with self-report insomnia and sleep quality measures. Higher depressive symptomatology was associated with higher subjective sleep disturbance on PSQI and worse insomnia symptoms on ISI in both sexes, accounting for 29-42% of the variance. Support: none 0737 DIAGNOSTIC VALUE AND FINANCIAL EFFECTS OF RECERTIFICATION POLYSOMNOGRAPHY IN MEDICARE PATIENTS WITH OBSTRUCTIVE SLEEP APNEA Neill, S. E. Majid, R. University of Texas Health Science Center in Houston, Houston, TX. Introduction: The annual cost of diagnosis and treatment of obstructive sleep apnea (OSA) exceeds 12.4 billion dollars in the United States. The Centers for Medicare and Medicaid Services (CMS) require that after initiation of positive airway pressure (PAP) therapy patients have physician follow up and comply with specific requirements. Otherwise, continued PAP benefits are terminated and patients must undergo repeat sleep testing to reinstate therapy. Repeat testing can become an economic burden. We hypothesize that restudying patients prior to reinstating PAP therapy does not change the diagnosis and may only result in increased health care costs. Methods: A chart review of polysomnographic studies (PSG) was performed on Medicare referrals made for the purposes of recertification to the Memorial Hermann Sleep center between October 2018 and 2019. Demographic and diagnostic data (including AHI) were collected. The percentage of patients with a change of diagnosis between the initial study and the recertification study was documented. Results: 429 Medicare patients were referred for polysomnography. 34 patients were referred for PAP recertification. The average age in the recertification group was 65 years, 47% were male with an average BMI of 33.4 kg/m2. The average AHI on the recertification study was 33.5 events/hour (range 7-114). None of the patients sent for PAP recertification by polysomnography had a negative study for OSA. Conclusion: Repeat PSG did not change the need for PAP therapy in patients originally diagnosed with OSA (all the patients continued to qualify). The mandatory referral of all patients who do not meet the CMS requirements for continued benefits for PAP, represents an extra cost to the health care system without a change in the clinical therapy. This money may better be utilized in providing patient education known to improve adherence to PAP. Support: N/A Downloaded from https://academic.oup.com/sleep/article/43/Supplement_1/A280/5846444 by guest on 09 December 2023 Methods: A total of 452 patients with OSA, who were free of previously diagnosed diabetes mellitus, were consecutively recruited. All participants underwent overnight polysomnography and 75-g oral glucose tolerance test. Patients were divided into normal glucose tolerance (NGT) and hyperglycemia (i.e. prediabetes and type 2 diabetes) according to the ADA criteria. The association between hyperglycemia and sleep architecture was examined using logistic regression model. Results: Of 452 patients, 283 (63%) had hyperglycemia (age 43.9 ± 11.1) and 169 (37%) had NGT (age 40.1 ± 11.1). Compared to the NGT group, the hyperglycemia group had older age (P < 0.05), higher body mass index (27.5 ± 4.1 vs. 26.33 ± 4.4; P < 0.05) and higher AHI (apnea-hypopnea index) (57.41 ± 28.6 vs. 48.3 ± 28.2; P < 0.05). There were no differences in total sleep time, the percentage of time spent in rapid eye movement (REM) or non-rapid eye movement (NREM) sleep between groups. However, patients with hyperglycemia had more microarousal events, especially during the NREM sleep (214 (range 19-662) events/h vs. 148 (range 37-600) events/h; P < 0.05). In addition, sleep variables related to oxygen saturation measures, such as the percentage of time spent with oxygen saturation ≤80%, were significantly greater during the REM sleep in patients with hyperglycemia (1.4 (total range 0-91.1) % vs. 1.1(0-78.6) %; P < 0.05). After adjusting potential confounders, logistic regression analyses showed that the presence of hyperglycemia was independently associated with the number of microarousals in NREM sleep (OR = 1.01, 95% CI = 1.00-1.02, P = 0.02). Conclusion: Hyperglycemia is independently associated with abnormal sleep architecture among patients with OSA. Patients with hyperglycemia have significantly increased sleep fragmentation in NREM sleep and significantly increased hypoxia in REM sleep. Support: This work was supported by the National Natural Science Foundation of China (81700087).