Daily rhythm and metabolic syndrome: a study of 272 adults
Study of 272 adults with a wrist device: metabolic syndrome was linked more to heart rate rhythms than to sleep. An association, not a cause.
Blog · Sleep
2025 American Heart Association statement: sleep health has several dimensions, but for now Life's Essential 8 counts only its duration.

In 2025 the American Heart Association published a scientific statement in Circulation: Cardiovascular Quality and Outcomes on sleep health and its link with cardiometabolic health. It points out that since 2022 sleep duration has been one of Life's Essential 8, the eight measures the AHA uses to describe cardiovascular health. And it proposes looking at sleep along several dimensions: duration, continuity, timing, regularity, daytime functioning, sleep stages and the absence of sleep disorders.
The AHA's Life's Essential 8 are: diet, physical activity, nicotine exposure, sleep health, body weight, cholesterol, blood glucose and blood pressure. Sleep entered the list in 2022, when evidence associating it with cardiometabolic health, and partly pointing to a causal link, had accumulated. For now the list considers only duration: for the other dimensions, the authors write, data are still scarce.

According to the statement, poor sleep health is associated with heart disease, stroke, high blood pressure and lipids, inflammation, glucose intolerance, obesity and higher mortality, both overall and cardiovascular.
These are associations: the authors call for studies showing whether improving sleep also improves heart health.
The statement reports meta-analyses in which disturbed sleep continuity, such as insomnia symptoms, is associated with hypertension, arterial stiffness, coronary heart disease, atrial fibrillation and myocardial infarction. No association emerged with atherosclerosis, dyslipidaemia or mortality.
Recording sleep is one thing. Interpreting it is for your doctor.
The Digital Twin lines up the data your devices write to your phone, such as steps, heart rate and sleep, and shows you how they change over time. It is not cardiovascular screening, it does not calculate risk profiles and it does not diagnose: this research describes groups of people, not you. The statement encourages doctors to ask patients “How is your sleep?”: the trend of your sleep can be a starting point for that conversation with your doctor.
The source is at the bottom. Open it.
This summary starts from research by others. It is not medical advice for you: talk it over with your doctor.
Study of 272 adults with a wrist device: metabolic syndrome was linked more to heart rate rhythms than to sleep. An association, not a cause.
Study of 413 people with early Parkinson's: probable REM sleep behaviour disorder was linked to faster cognitive decline. An association, not a cause.
Study of 1,992 adults: highly variable sleep duration and timing were linked to about double the cardiovascular risk. An association, not a cause.
More studies, same rule: read the source.