A Nature Communications study introduces a foundation model trained on more than 10,000 Cleveland Clinic sleep studies linked to long-term records. Embeddings sorted patients into five risk groups whose mortality and heart-failure trajectories separated far more cleanly than standard apnea-hypopnea index bands. The highest-risk group had more than double the mortality risk of the lowest in the clinical cohort, with similar gradients in the Sleep Heart Health Study. Caveat: the work is retrospective risk stratification, not a trial showing that acting on these groups improves outcomes.