Sleep Medicine

Tirzepatide improves cardiometabolic risk in OSA via both weight and OSA physiology

In SURMOUNT-OSA, tirzepatide reduced multiple cardiometabolic risk factors more than placebo in adults with moderate-to-severe OSA and obesity. Mediation analyses showed independent effects of improved OSA metrics on hs-CRP, insulin resistance, and triglycerides, beyond weight loss alone. Systolic blood pressure improvements were mediated by both weight loss and OSA changes, while diastolic pressure showed no clear mediation. Findings suggest that optimising both obesity and sleep-disordered breathing is needed to maximise cardiometabolic benefit in OSA patients. 1

Sleep fragmentation, not AHI, predicts longitudinal brain atrophy

In this population-based cohort (n=387; 7-year follow-up), baseline AHI and ODI did not predict later structural brain changes. Lower mean nocturnal SpO2 was associated with reduced total brain volume on follow-up MRI. Higher arousal index predicted increased brain age and reduced global and regional grey matter thickness over time. Subjective sleep quality also correlated with brain volume changes, highlighting fragmentation and hypoxemia as key neurodegenerative drivers in sleep apnoea. Targeting sleep fragmentation may provide neuroprotective benefit even when traditional severity indices appear modest. 2

SleepGPT foundation model sets new bar for automated PSG decoding

SleepGPT is a generative transformer-based, time–frequency foundation model trained on 86,335 hours of PSG from 8,377 subjects. It incorporates channel-adaptive processing and unified time–frequency fusion, enabling robust performance across variable PSG montages. Across multiple datasets, SleepGPT outperformed prior methods for sleep staging, sleep pathology classification, sleep spindle detection, and synthetic data generation. The model also highlighted channel- and stage-specific physiological patterns, offering interpretability alongside performance gains. These results support near-future clinical deployment of scalable, high-accuracy automated scoring and phenotyping in sleep labs. 3

CADM2/beat-Ia loss links developmental circuitry to adult hypersomnia

This cross-species study implicates synaptic adhesion molecules beat-Ia/CADM2 in the pathogenesis of excessive daytime sleepiness and idiopathic hypersomnia. Neuronal knockdown of beat-Ia in Drosophila and loss of its vertebrate ortholog CADM2 in fish produced markedly increased sleep. Beat-Ia loss disrupted developmental synaptic elaboration of neuropeptide F neurites onto suboesophageal zone GABAergic neurons that stabilise arousal. An NPY receptor agonist normalised sleep in zebrafish lacking CADM2, implicating NPY pathway modulation as a potential therapeutic strategy. These findings provide a mechanistic and genetic framework for targeted treatments in central hypersomnias. 4