Irregular Bedtime Linked to Higher Heart Attack and Stroke Risk, Study Shows

HANOI, April 2 — New research indicates that it isn’t staying up late that poses the greatest danger to heart health — but rather having an irregular bedtime schedule that may double the risk of serious cardiovascular events, including heart attack and stroke.

The study, tracking more than 3,200 adults over more than a decade, found a clear link between inconsistent sleep timing and increased heart‑related risks. Participants wore monitoring devices to measure both the duration and timing of their sleep patterns, giving researchers detailed insight into how bedtime consistency affects cardiovascular health.

Results showed that individuals with highly variable bedtimes faced as much as twice the risk of heart attack or stroke compared with those who maintained consistent sleep schedules. The risk was notably stronger among participants who slept fewer than eight hours a night.

Interestingly, the new findings suggest that wake‑up times alone did not significantly correlate with major heart problems — underscoring that when you go to sleep may be more important than when you wake up.

Researchers believe the connection may stem from the disruption of the body’s circadian rhythm, the internal biological clock that regulates vital processes such as metabolism, hormone release, and cardiovascular function. Previous studies have shown that irregular sleep patterns can increase inflammation, blood pressure variability, and other factors linked to heart disease.

Another international study involving more than 72,000 adults found that irregular sleep schedules were associated with roughly a 26% higher likelihood of stroke‑related events compared with individuals who maintained regular sleep and wake times.

Health experts say that while total hours of sleep remain important, consistency in bedtime plays a key role in maintaining circadian rhythm stability, which in turn influences cardiovascular health.

To help reduce the risk of serious heart conditions, clinicians urge adults to aim for:

• Regular bedtime and wake‑up schedules every day, even on weekends.
• At least 7–8 hours of sleep per night, aligning with most adult health recommendations.
• Improving sleep hygiene, such as limiting screen time before bed and avoiding stimulants late in the day.

Maintaining a consistent sleep routine is a simple lifestyle measure that could have far‑reaching benefits for heart health, researchers say — potentially lowering the risk of heart attack, stroke, and other cardiovascular diseases in the long term.