For how we live.
Sleeping apart is increasingly common and can genuinely cut disturbance. But the lab evidence is double-edged: sharing a bed measures as slightly worse sleep yet feels better, and may even boost REM.
Wrist trackers infer light, deep and REM sleep from movement and pulse. Two validation studies find they track total sleep passably but each misjudges the stage breakdown its own way.
In 7,530 people from two long-running cohorts, central sleep apnea with high oxygen overshoot carried elevated cardiovascular risk. The same apnea with low overshoot did not.
In 152 adults tested against two nights of polysomnography, the Galaxy Watch reached an AUROC of 0.94 for moderate-to-severe sleep apnea — with 66.7% specificity at the setting it ships with.
Stanford's SleepFM, published in Nature Medicine in January 2026, is the most consequential sleep paper of the year. Its own limitations section explains why it is not yet a clinical test.
Only three of the 15 studies pooled in a Chilean meta-analysis used sleep testing at all. A Lima clinic analysis shows why that shortcut matters.
A consortium reduced overnight sleep studies to nine composites. Two tracked with better cognition. None tracked with whether a person later developed dementia.
In 2,286 patients with sleep apnea undergoing major surgery, a measure of how deeply and how long oxygen fell — not the apnea-hypopnea index — tracked 30-day cardiovascular events and death.
In a Pennsylvania cohort followed 7.5 years, the combination carried the highest risk when insomnia came with objectively short sleep. Insomnia with normal sleep duration showed no significant association.
A meta-analysis of 22 crossover trials with overnight polysomnography found consistent losses in total sleep time and efficiency. The age and dose subgroup differences everyone wants were not statistically significant.
Seltorexant held its effect over two weeks while zolpidem's faded, in a 364-person study run in 2017-2019 and published only now. The delay is disclosed in the paper itself.