Abstract Introduction Obstructive sleep apnea (OSA) is common but often underdiagnosed and undertreated. Expanding the role of primary care providers (PCPs) may improve timely diagnosis and treatment of OSA, but patients report higher positive airway pressure (PAP) therapy adherence when cared for by specialists at centers accredited by the American Academy of Sleep Medicine. At Mayo Clinic, PCPs are now authorized to order home sleep apnea testing (HSAT) and subsequent therapy; HSAT is reviewed and interpreted by Sleep Medicine specialists (SMSs), but patients receive diagnoses and treatment recommendations through their PCP. This retrospective study evaluates whether patients diagnosed with OSA through primary and specialty care pathways experience comparable timeliness of care, counseling about therapeutic options, and PAP adherence. Methods Fifty-five patients were selected from each of two groups, based on whether their HSAT was ordered and initially managed by a PCP or SMS. Initial sleep metrics, PAP therapy adherence data, and other management details (treatments offered and key dates in the care pathway) were compared across groups. Results Once HSAT had been ordered, provider type was not associated with meaningful discrepancies in diagnosis and treatment timeliness; PCP-managed patients waited just one additional day after the interpretation of their HSAT to be offered treatment (p=0.025). However, consultation with Sleep Medicine introduced upfront delays caused by limited access to specialty care. The total time in the OSA care pathway, between referral to a SMS or pre-HSAT evaluation to the offering of treatment was 113 days for SMS patients versus 28 days for PCP patients (p< 0.001). Additionally, SMSs identified more co-occurring sleep disorders and discussed a broader range of treatment options with their patients, who demonstrated nightly PAP usage of 1.15 hours longer on average. Conclusion Despite differing modes of patient communication, PCPs offer timely OSA testing and diagnosis, allowing patients to bypass lengthy specialty care wait times. However, future efforts are needed to address variations in the counseling provided, and to ensure that all patients are equipped to succeed with PAP therapy. These findings support primary care pathways for uncomplicated OSA while highlighting the need for enhanced education and support to optimize patient outcomes. Support (if any)
0346 Retrieval Augmented Generation Improves Large Language Model Performance in Sleep Medicine
Abstract Introduction While Large Language Models (LLMs) offer generative capabilities, generic models often lack domain-specific grounding, leading to hallucinations in high-stakes contexts. However, LLMs can serve as clinical decision support tools if augmented with specific domain data. This study evaluates the utility of Retrieval-Augmented Generation (RAG) applied to open-source LLMs, utilizing a curated knowledge base of authoritative sleep medicine textbooks, to quantify improvement in performance. Methods We evaluated four open-source models—Llama-70B, Llama-8B, Qwen-14B, and Qwen-235B, linked to a RAG system indexing five standard textbooks, including ICSD-3 TR. Models were tested on sleep board–style MCQs and clinical vignettes diagnostic accuracy. Performance was assessed across nine configurations derived from three factors: RAG pipeline complexity (Plain vs. Complicated), textbook preprocessing (Uncleaned vs. Cleaned/TOC-aligned), and retriever type (Dense-only vs. Hybrid). Metrics included MCQ Accuracy and the rates at which the correct diagnosis appeared as the top result or within the top 5 differential diagnosis lists for vignettes. Results RAG consistently outperformed the no-RAG baseline, yielding absolute performance gains of 5.6%–10.7% for MCQs and 8.1%–10.2% for the top diagnosis in cases across all models. For MCQs, Qwen-235B achieved the highest accuracy of 87.3% (vs. 81.7% baseline) using the Plain RAG configuration with Cleaned (TOC-aligned) Hybrid retrieval. Llama-70B followed with 83.6% in the same configuration. For case vignettes, Qwen-235B achieved a correct top diagnosis rate of 66.3% and a correct diagnosis rate within the top 5 differential diagnosis lists of 90.8% using Cleaned Hybrid retrieval configurations. Hybrid retrieval (Dense + Sparse) consistently surpassed Dense-only methods. Notably, while larger models benefited from Cleaned text, smaller models (e.g., Qwen-14B) achieved higher top diagnosis rates with Uncleaned text (57.1% vs. 51.0%), suggesting a dependency on redundant context in lower-parameter settings. Conclusion RAG significantly enhances knowledge performance of open-source LLMs in sleep medicine. Hybrid retrieval and curated, TOC-aligned knowledge bases yield optimal results for large models, whereas smaller models benefit from the redundancy of uncleaned text. These findings suggest that RAG systems can augment LLMs in domain specific knowledge for clinical decision support. Support (if any)
0566 Baseline Characteristics of Central Sleep Apnea Patients Treated with Transvenous Phrenic Nerve Stimulation in the reST Study
Abstract Introduction The remedē System® Therapy Study (reST) is a real world evaluation using transvenous phrenic nerve stimulation (TPNS) to treat adults with moderate-to-severe central sleep apnea (CSA). Based on previous clinical trials, it was expected that most patients with CSA would have heart failure (HF). However, recent CSA prevalence publications demonstrated the opposite. We present the baseline characteristics of patients with CSA treated with TPNS. Methods Adult subjects determined eligible for a commercial TPNS device implant by routine clinical PSGs were consented to participate in the trial. Baseline assessments were performed and medical history collected. Patients will be followed for ≥1 year following therapy activation; follow-up is ongoing. This report describes the baseline characteristics of the patient population. Results Twenty-nine sites enrolled a total of 197 subjects (171 United States & 26 the Netherlands) between July 2019 and March 2025. Median [Q1-Q3] age was 70 [61-76] years, 82% were male, and 97% white race. Body mass index was 28.7 [25.8-31.6] kg/m2, with neck size 41 [28-44] cm. Patients had moderate-to-severe CSA with site-reported apnea-hypopnea index of 46/hour [30-64], including central apnea index of 24/hour [13-38]. Despite a range of comorbidities among patients, HF was documented in just 23%. Other cardiovascular conditions were more prevalent, including hypertension (70%), hyperlipidemia (65%), coronary artery disease (37%), atrial fibrillation (34%), and prior stroke (14%). Non-cardiac issues such as depression (27%), diabetes (26%), and renal disease (18%) were also present. Additionally, 22% of patients used narcotics, and 89% had previously failed another CSA therapy, most often CPAP (79%), Bi-PAP (39%), or ASV (32%). Lastly, almost 20% were from high altitude locations (>5,000 feet). Conclusion Patients implanted with TPNS had significant co-morbidities. However, HF was much less common than anticipated. This finding could be due to CSA being present in clinical practice with a wider range of underlying causes beyond HF, or undiagnosed early-stage HF. Alternatively, it may reflect referral bias for this specific therapy, with patients selected because of prior treatment failures or other comorbidities. These possibilities highlight the importance of recognizing CSA in a diverse patient population and underscore the need for multidisciplinary team management. Support (if any) ZOLL Respicardia, Inc.
0722 Demographic and Clinical Characteristics of People Receiving Once-Nightly Sodium Oxybate Treatment: A Specialty Pharmacy Data Analysis
Abstract Introduction Once-nightly sodium oxybate (ON-SXB [LUMRYZ™]) is approved to treat excessive daytime sleepiness (EDS) or cataplexy in patients ≥7 years of age with narcolepsy. Real-world demographic/clinical characteristics and treatment adherence in patients with narcolepsy who received ON-SXB from a specialty pharmacy were assessed. Methods Baseline demographic/clinical data were collected from Optum Frontier Therapies pharmacy for patients with ≥1 filled ON-SXB prescription, ≥1 ON-SXB-related clinical assessment, and baseline Epworth Sleepiness Scale (ESS) score from 6/1/2023-9/30/2024. Adherence (≥80% of days covered) was assessed for patients with ≥3 months of ON-SXB use. Data were stratified by narcolepsy subtype (narcolepsy type 1 [NT1] and 2 [NT2] when available) and prior oxybate use (transitioned from prior oxybate therapy to ON-SXB ≤30 days of index [switch]/were oxybate-naive or discontinued oxybate >30 days before index [not-on-oxybate]). Data were analyzed descriptively. Results 452 patients were identified (NT1, 55%; NT2, 37%; NT unknown, 9%; switch, 40%; not-on-oxybate, 60% [oxybate-naive, n=147/271]). Mean (range) age was 38.9 (16.0-88.0) years. Most patients were female (68%) and had commercial insurance (78%). Overall, 67% of patients had prior oxybate use (NT1, 72% [n=179/247]; NT2, 59% [n=98/166]; switch, 100%; not-on-oxybate, 46% [n=124/271]); for these patients, the most common oxybate (65%) was mixed-salt oxybates (NT1, 61%; NT2, 70%; switch, 61%; not-on-oxybate, 70%). Overall, 64% of patients used stimulants/wake-promoting agents (WPAs) (NT1, 64%; NT2, 65%; switch, 60%; not-on-oxybate, 67%). Overall, the mean (SD) baseline ESS score was 12.0 ([5.5]; NT1, 11.7 [5.5]; NT2, 12.5 [5.3]; switch, 11.0 [5.7]; not-on-oxybate, 12.7 [5.3]). At baseline, 29% of patients experienced severe EDS (ESS score ≥16: NT1, 26%; NT2, 30%; switch, 20%; not-on-oxybate, 34%). Of 269 patients with ON-SXB use ≥3 months, 84% (NT1, 84%; NT2, 89%; switch, 94%; not-on-oxybate, 76%) demonstrated adherence. Conclusion Patients not on an oxybate had the highest baseline ESS scores and proportion with severe EDS, despite greater stimulant/WPA utilization. Patients with NT1 used oxybates more frequently than those with NT2 despite those with NT2 having higher baseline ESS scores and a greater proportion having severe EDS, suggesting oxybates merit earlier consideration in patients with NT2. Most patients demonstrated ON-SXB adherence, indicating they would likely receive full therapeutic benefit. Support (if any) Avadel Pharmaceuticals
0560 Associations of Late Midlife Sleep-Disordered Breathing with Late-Life Brain Amyloid Deposition
Abstract Introduction Sleep-disordered breathing (SDB) is a potentially modifiable risk factor for the prevention of dementia, of which Alzheimer’s disease (AD) is the most common cause. However, there is a lack of longitudinal evidence relating SDB to AD pathology >20 years later. We examined the association between late-midlife SDB and late-life brain β-amyloid (Aβ) deposition—a hallmark of AD—assessed approximately 23 years later. Methods The Atherosclerosis Risk in Communities (ARIC) Study is an ongoing prospective cohort study initiated in 1987. Participants at two ARIC sites (Washington County, Maryland; Minneapolis, Minnesota) with primarily White participants also completed polysomnography (PSG) in the Sleep Heart Health Study (SHHS) in 1995-98. SDB measures included apnea-hypopnea index (AHI; number of apneas + hypopneas with ≥3% oxygen desaturation/hour of sleep), arousal index, and percentage of total sleep time in apnea, in hypopnea, and with oxygen saturation < 90%. A subset of participants completed florbetapir positron emission tomography (PET) scans through several ARIC ancillary studies (2011-2025 including the ARIC Sleep-PET study). We defined Aβ deposition as a global standardized uptake value ratio (SUVR) >1.2 (vs. SUVR ≤1.2). We used Poisson regression with robust standard errors to estimate relative risk (RR) of Aβ deposition by SDB, adjusting for demographics and vascular risk factors, and applied inverse probability attrition weighting to account for selective drop-out. Results Among 186 dementia-free participants (mean age=59 years at PSG and 82 years at PET scan, 58% female, 98% White), every 10% increase in total sleep time in hypopnea was associated with higher risk of Aβ deposition (RR=1.40, 95% confidence interval [CI]: 1.03, 1.91). When compared to no SDB (AHI < 5), moderate to severe SDB (AHI ≥15) was associated with elevated Aβ deposition (RR=2.36, 95% CI: 1.22, 4.57); mild SDB (AHI 5 to < 15) was not (RR=1.05, 95% CI: 0.53, 2.07). Conclusion SDB in late midlife was associated with greater risk of Aβ deposition approximately 23 years later. SDB may play a role in the early stages of AD pathogenesis. Future longitudinal studies are needed to optimize strategies for screening and treating SDB for dementia prevention. Support (if any) Supported in part by RF1AG050745.
0559 The XXY Connection: Exploring the Prevalence of Sleep Disorders in Klinefelter Syndrome
Abstract Introduction Klinefelter syndrome (KS) is a chromosomal condition marked by hypogonadism and disturbances in hormonal regulation. The relationship between KS and co-occurring sleep disorders has not been extensively characterized, creating a need for more detailed investigation. Methods We identified individuals with Klinefelter syndrome (KS) evaluated at our institution between January 2000 and December 2025 using ICD-9 and ICD-10-CM codes. Electronic health records were then manually reviewed to confirm KS status and to exclude miscoded entries. For confirmed cases, we extracted data on sleep-related complaints, diagnoses, diagnostic testing (overnight oximetry, polysomnography, home sleep testing), and treatment. Sleep disorders were categorized operationally: obstructive sleep apnea (OSA), central sleep apnea (CSA), insomnia, hypersomnia/narcolepsy, or other according to documented clinician diagnosis or diagnostic test results. When structured Sleep Center data were available, these were included. We summarized cohort characteristics using means (± SD) or medians (interquartile range) as appropriate. For comparison between subgroups (e.g., those with vs without documented sleep-disordered breathing), we applied Welch’s t-test and binomial proportion tests. Analyses were conducted using Python scripts and spreadsheet software. Results Nearly one-third of patients with confirmed KS in this series had either diagnosed or suspected obstructive sleep apnea (OSA), substantially exceeding prevalence estimates in the general population. The frequency of central sleep apnea (CSA) was comparable to that seen in the general population, however its occurrence without usual predisposing factors suggests a predisposition toward idiopathic CSA in KS. Circadian rhythm disorders were rare, occurring in < 1% of the cohort. Notably, nearly 75% of KS patients with documented sleep-related symptoms had never undergone formal evaluation in a Sleep Center. Conclusion The observed rate of presumed idiopathic CSA among individuals with KS suggests the possibility of KS-specific mechanisms affecting ventilatory control stability. Additionally, there appeared to be a larger prevalence of OSA in this patient population. Notably, approximately three-quarters of KS patients who reported sleep-related symptoms had never undergone a formal Sleep Medicine assessment, highlighting a significant gap in structured evaluation that may relate to limited access to specialized care, referral patterns, or other systemic barriers, and warrants additional study. Support (if any) None
0696 Lifestyle Factors in Narcolepsy and Idiopathic Hypersomnia
Abstract Introduction Narcolepsy and idiopathic hypersomnia (IH) are characterized by excessive daytime sleepiness. They can be caused by deficiency of orexin/hypocretin, a neuropeptide that regulates sleep and wakefulness. It is estimated that 1 in 2000 people in the United States of America have been diagnosed with some form of narcolepsy or idiopathic hypersomnia. Around the world, about 3 million people are narcoleptic. Little data are available regarding the lifestyle factors in these patients. In this study, we sought to find whether lifestyle factors, including diet and physical activity are associated with the severity of sleepiness in narcolepsy and idiopathic hypersomnia. Methods We collaborated with “Hypersomnia Foundation” and “Wake Up Narcolepsy” who distributed our survey to their subscribers. The survey consisted of a series of four short subsurveys asking about the substance use, diet (MiniEAT screen), exercise (IPAQ questionnaire), and daytime sleepiness (Epworth Sleepiness Scale). The survey was anonymous and included baseline characteristics, diagnosis (Narcolepsy type 1 (NT1), Narcolepsy type 2 (NT2), or Idiopathic Hypersomnia (IH)). We considered hypersomnolence and moderate to severe hypersomnolence to be present if ESS >10 and ≥15, respectively. Results We received total of 377 individual responses. Of those, 191 responders had IH, 97 had NT1 and 89 had NT2. Median age was 31 (25, 42) and 323 identified as females, 44 males and 10 others. Median ESS was 15 (12, 18), where 285 responders had ESS >10 (76%) and 194 (51%) had ESS >/=15. The ressponders with NT1 had significantly higher median ESS: 17 (12,19), than NT2: 15 (10, 17), or IH: 15(12, 17) responders (p< 0.01). In multiple univariate analyses, none of the baseline characteristics, habits (smoking, alcohol or caffeine), dietary consumption (fruit, vegetable, legumes/nuts/seeds, whole or refined grains, dairy and fish/seafood) or exercise (vigourous, moderate or walking) had significant association with the degree of responders’ subjective sleepiness. Conclusion Most survey responders continue to be excessively sleepy, particularly those with NT1. There were no apparent univariate associations of underlying hypersomnolence with the baseline characteristics, habits, diet and exercise levels. Disorders of central hypersomnolence are of complex nature without easily identifiable modifiers. Support (if any) Mayo Clinic CRISP
0112 Increasing Sleep Regularity is Associated with Improvements to Heart Rate Variability in Healthy Adults
Abstract Introduction Sleep regularity has been shown to be a stronger predictor of mortality compared to sleep duration, though the underlying mechanisms are incompletely understood. Heart rate variability (HRV), a measure of cardiac autonomic modulation, is associated with cardiovascular morbidity and mortality. While HRV is traditionally analyzed using linear methods (e.g., frequency-domain analyses), there is growing interest in nonlinear measures to assess the dynamic complexity of cardiac regulation. However, the influence of sleep regularity on both linear and nonlinear HRV is unclear. We therefore assessed the association between sleep regularity and HRV in healthy adults. Methods HRV was obtained in 12 participants (6 female) via electrocardiography during 10-min supine rest and assessed using linear (high frequency [HF]; low frequency [LF]/HF ratio) and nonlinear (detrended fluctuation analysis [DFA]-α1 and -α2) indices. Sleep regularity was quantified using the standard deviation (SD) of diary-determined sleep onset across ~14 days. Participants were classified as regular (SD< 1h; n=5) or irregular sleepers (SD>=1h; n=7). Irregular sleepers were instructed to maintain a consistent sleep onset (±30min) for 12-weeks. Differences between groups were assessed using independent t-tests and relationships between SD sleep onset and HRV were assessed using Pearson correlation analyses. Results There were no differences between groups in age (mean±SD, irregular vs. regular, respectively; 30.7±7.8 vs. 27.2±8.5y; p=0.23), sleep onset timing (24:38±1:45 vs. 23:37±1:14; p=0.14), or DFA-α2 (0.27±0.11 vs. 0.36±0.20; p=0.16). At baseline, irregular sleepers had higher SD sleep onset (1.4±0.4 vs. 0.8±0.2h; p< 0.01), LF/HF ratio (2.4±1.8 vs. 0.6±0.5%; p=0.03), DFA-α1 (1.10±0.22 vs. 0.81±0.20; p=0.02), and lower HF (37.1±20.5 vs. 63.1±7.1nu; p=0.02). In the entire sample, SD sleep onset was inversely correlated with HF (r=-0.63; p=0.02) and positively correlated with LF/HF ratio (r=0.75; p< 0.01) and DFA-α1(r=0.61; p=0.03) at baseline. At 12-weeks, the change in SD sleep onset was inversely correlated with change in HF (r=-0.79; p< 0.01) and positively correlated with change in LF/HF ratio (r=0.77; p< 0.01) and DFA-α1(r=0.66; p=0.01). Conclusion Irregular sleep patterns are associated with altered cardiac regulatory dynamics and may be one mechanism contributing to adverse outcomes. Improving sleep regularity may be a potential interventional target to improve the autonomic balance and cardiovascular adaptation. Support (if any)
Adamantinomatous craniopharyngioma: outcomes from a US multicenter registry cohort (RAPID consortium study)
OBJECTIVE Adamantinomatous craniopharyngioma (ACP) is a rare type of brain tumor that affects a wide age range, from children to older adults. Due to the rarity of the disease, existing studies are predominantly limited to single-center or single-surgeon experiences, often lacking statistical power and generalizability. The aim of this study was to address this gap by providing a comprehensive analysis of ACP outcomes based on a large multicenter cohort from the Registry of Adenomas of the Pituitary and Related Disorders (RAPID). METHODS This multicenter retrospective cohort study was conducted via the RAPID consortium and assessed patients with histologically confirmed ACP treated surgically between August 2000 and November 2024 at high-volume pituitary centers across the United States. RESULTS Among the 359 patients (206 male, median age at primary surgery of 47 years) included in the analysis, 76% underwent endoscopic transsphenoidal surgery and 22% underwent craniotomy. Gross-total resection was achieved in 45% and subtotal resection in 47%. Notably, 120 of 311 patients (39%) presented with preoperative hypothalamic-pituitary axis dysfunction. Following all treatments, permanent hypothyroidism was reported in 40% of patients, adrenal insufficiency in 33%, and arginine vasopressin deficiency in 19%. Of 263 patients who underwent primary surgery, radiation therapy was administered in 84 (32%). Progression-free survival (PFS) declined from 66% at 1 year to 31% at 6 years. In the multivariable analysis, independent predictors of worse PFS included subtotal resection (HR 0.22, 95% CI 0.11–0.42; p = 0.001), partial resection (HR 0.11, 95% CI 0.04–0.28, p = 0.001), larger tumor size (HR 0.77, 95% CI 0.64–0.94; p = 0.009), and tumor extension beyond the sella and suprasellar regions (HR 0.21, 95% CI 0.06–0.74; p = 0.016). Primary surgery and salvage surgery groups showed comparable PFS. CONCLUSIONS In this large multicenter cohort study, gross-total resection was achieved in fewer than half of patients and was independently associated with improved PFS. Approximately one-third of patients underwent radiation therapy after primary surgery. These findings provide robust evidence supporting the prognostic value of extent of resection and inform contemporary treatment algorithms for ACP. The high incidence of postoperative endocrinopathy underscores the need for individualized multidisciplinary long-term care. While the retrospective design is a limitation, the multicenter approach enhances the generalizability of these results.
Individualized multiparadigm mapping and standardized tablet-based task administration during awake craniotomy: associations with return to work and survival in diffuse gliomas
OBJECTIVE Protocols for intraoperative mapping during awake craniotomy vary widely. The aim of this study was to evaluate how the number and type of intraoperative neuropsychological paradigms administered via NeuroMapper, a tablet-based platform, during awake glioma surgery affect positive mapping rates, return to work (RTW), and oncological outcomes. Factors associated with the operative duration and early postoperative neurological deficits were of additional interest. METHODS This single-center retrospective study included patients with diffuse low- and high-grade gliomas who underwent awake craniotomy with NeuroMapper-guided mapping between 2018 and 2024. Primary outcomes were RTW, progression-free survival (PFS), and overall survival (OS); operative duration and early postoperative deficits were secondary outcomes. Covariate balancing propensity score (CBPS) analysis was used to address confounding by tumor grade, with all postweighting standardized mean differences < 0.10. A weighted logistic regression model assessed RTW, and CBPS-weighted Cox models assessed PFS and OS. Linear regression was used to analyze intraoperative variables, operative duration, and early postoperative deficits. RESULTS Of 189 patients included in the analysis, 65 had LGG (median age 39 years) and 124 had HGG (median age 56 years). Mapping complexity varied, with 1–6 tasks used (median 4). Weighted multivariate logistic regression analysis identified the following independent predictors of RTW: preoperative Karnofsky Performance Status score ≥ 80 (OR 1.37, p = 0.039), absence of recurrent disease (OR 0.30, p < 0.001), use of 5–6 paradigms (OR 1.54, p = 0.047), positive mapping (OR 2.41, p = 0.017), and subtotal resection (OR 4.43, p = 0.002). Intraoperative seizure, early postoperative deficit, and the resection technique were not significant. IDH mutation status was associated with improved PFS (HR 0.15, p < 0.001), while subtotal resection was associated with worsened PFS (HR 3.00, p < 0.001). Positive mapping was associated with better OS (HR 0.57, p = 0.04). The operative duration was unaffected by mapping variables but was longer in patients with obesity (β = 0.28, p = 0.038). CONCLUSIONS Positive NeuroMapper-guided mapping of more diverse linguistic functions was associated with RTW and longer OS. Additionally, mapping complexity did not prolong surgery times, supporting potential standardization.