New research reveals that an inconsistent sleep schedule could increase your risk of heart problems by up to 26% – regardless of how many hours you spend in bed. This finding challenges the common belief that getting enough sleep is all that matters for heart health.
Published in Journal of Epidemiology & Community Health | Estimated reading time: 4 minutes
When it comes to sleep health, timing might matter just as much as duration. A comprehensive study of over 72,000 UK adults has uncovered a compelling link between irregular sleep patterns and cardiovascular events, even among those who achieve the recommended 7-9 hours of nightly rest.
The research team, led by Dr. Jean-Philippe Chaput from the University of Ottawa, tracked participants’ sleep patterns using activity monitors for a week. They calculated each person’s Sleep Regularity Index (SRI) score – a measure of how consistently someone maintains their sleep and wake times. Those with the most irregular patterns showed a 26% higher risk of experiencing major cardiovascular events like heart attacks and strokes over the following eight years.
“More importantly, our results suggest that sleep regularity may be more relevant than sufficient sleep duration in modulating cardiovascular risk,” explains Dr. Chaput. The relationship between declining sleep regularity and increased heart risks appeared almost linear, with the protective effects becoming stronger as sleep patterns became more consistent.
What’s particularly striking is that achieving the recommended amount of sleep didn’t cancel out the risks for irregular sleepers. While 61% of regular sleepers met sleep duration guidelines compared to 48% of irregular sleepers, getting enough total sleep wasn’t enough to offset the cardiovascular risks associated with irregular patterns.
These findings from the UK Biobank study accounted for various factors including physical activity, screen time, diet, alcohol consumption, smoking, mental health, and shift work. The researchers suggest that sleep regularity deserves greater attention in both public health guidelines and clinical practice.
Glossary
- Sleep Regularity Index (SRI)
- A numerical measure of how consistently a person maintains their sleep and wake times, with higher scores indicating more regular patterns.
- Major Adverse Cardiovascular Events (MACE)
- Serious heart-related incidents including heart attacks, strokes, heart failure, and cardiovascular death.
- Cardiovascular Disease
- A group of disorders affecting the heart and blood vessels, often influenced by lifestyle factors including sleep patterns.
What percentage increased risk of cardiovascular events did the most irregular sleepers face?
Irregular sleepers faced a 26% higher risk of major cardiovascular events compared to those with regular sleep patterns.
Does getting enough total sleep hours offset the risks of irregular sleep patterns?
No, the study found that meeting recommended sleep duration didn’t offset the cardiovascular risks for irregular sleepers, though it did help moderately irregular sleepers.
What was considered a “regular” sleep pattern in the study?
People with a Sleep Regularity Index (SRI) score of more than 87 were considered to have a regular sleep pattern.
How long did researchers track participants’ cardiovascular outcomes?
The researchers tracked cardiovascular events over an 8-year period following the initial sleep assessment.
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