The Study
Associations of Accelerometer-measured Sleep Duration with Incident Cardiovascular Disease and Cardiovascular Mortality.
This study found that people who slept less than 7 hours a night were more likely to have heart problems later, but it doesn’t prove that short sleep caused those problems — maybe people who sleep less are also more stressed or less healthy in other ways.
Analysis score
Maximum 72 for a cohort study.
Where the score came from
Scientists tracked how long people slept using wrist devices and saw what happened to their hearts over 7 years.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 552 / 100
Quality score
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — for every 100 people who sleep too little, about 6 more will get heart disease and 3 more will die from it over 7 years compared to those sleeping 7–9 hours.
- 2People who slept less than 7 hours a day had a 6% higher risk of heart disease and a 29% higher risk of dying from it, compared to those who slept 7–9 hours.
- 3Sleeping more than 9 hours didn’t raise the risk.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Sleep
Year
2024
Authors
Mingqing Zhou, Yan Liang, Sizhi Ai, H. Feng, Yujing Zhou, Yaping Liu, Jihui Zhang, Fujun Jia, B. Lei
Related Content
Claims (5)
If you sleep 8 to 9 hours every night, you’re less likely to have heart problems later on.
People who sleep less than 7 hours a night are more likely to develop heart problems or die from them compared to those who sleep 7 to 9 hours, based on wearable device data.
People who sleep more than 9 hours a night don’t seem to have a higher chance of heart problems or dying from heart issues than those who sleep 7 to 9 hours, at least based on how their sleep was tracked with a wrist device.
Getting between 7 and 9 hours of sleep each night seems to be the sweet spot for lowering your risk of heart problems — sleeping less or more than that might raise your risk.
People who sleep less than 7 hours a night are more likely to develop heart problems like heart attacks or irregular heartbeats than those who sleep 7 to 9 hours.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.