Insomnia, or having five or fewer hours of sleep a night, increases the risk of heart attack, a new study suggests. Researchers say the findings underline the importance of prioritizing sleep.
The link between insomnia and heart attack is especially strong in women, according to the research published in the journal Clinical Cardiology. Between 10% and 30% of Americans suffer from chronic insomnia, making it the most common sleep disorder in the U.S. Women have a 40% higher lifetime risk of insomnia than men.
Researchers analyzed data for nearly 1.2 million adults from the U.S., the United Kingdom, Norway, Germany, Taiwan, and China, the majority (96%) of whom had not previously experienced a heart attack. Nearly half (43%) of the participants were women.
Some 13% of individuals had insomnia — either had received the official diagnosis or were experiencing any of these three symptoms: difficulty falling asleep, difficulty staying asleep, or waking early and not being able to get back to sleep.
During a follow-up of an average of nine years, heart attacks occurred in 2,406 of those in the insomnia group and 12,398 of those without insomnia.
The researchers also looked at the possible link between sleep duration and heart health. Those who reported five or fewer hours of sleep a night were 1.38 and 1.56 times more likely to experience a heart attack than those who slept six to eight hours a night, respectively.
"Insomnia is the most common sleep disorder, but in many ways, it’s no longer just an illness, it’s more of a life choice. We just don’t prioritize sleep as much as we should," said Yomna E. Dean, a medical student at Alexandria University in Alexandria, Egypt, and study author.
The study also adds to evidence that getting too much sleep may be unhealthy, as there was no significant difference in the heart attack risk between those sleeping five or fewer hours a night and those who reported getting nine or more hours of sleep a night.
Someone has a heart attack every 40 seconds in the U.S., and it is the leading cause of death for people of most racial and ethnic groups. The major heart attack symptoms include:
- Chest pain or discomfort, primarily in the center or left side of the chest, lasting for more than a few minutes before going away and then coming back.
- Feeling weak, light-headed, or faint.
- Pain or discomfort in the jaw, neck, or back.
- Pain or discomfort in one or both arms or shoulders.
- Shortness of breath.
How to improve my sleep
Having insufficient sleep has been previously linked to many chronic conditions, including type 2 diabetes, heart disease, obesity, and depression.
Adults between the ages 18 and 64 are recommended to have at least seven hours of sleep per night, according to the CDC.
You can improve your sleep by following these tips:
- Keep your bedroom cool, dark, and quiet.
- Eat meals at consistent times during the day and avoid heavy meals two to three hours before bed.
- Exercise for at least 20 minutes a day.
- Avoid screen time at least one hour before bed.
- Increase exposure to bright light upon waking and throughout the afternoon.
- Clinical Cardiology. Association between insomnia and the incidence of myocardial infarction: A systematic review and meta-analysis.
- American College of Cardiology. Insomnia Tied to Greater Risk of Heart Attack, Especially in Women.
- Centers for Disease Control and Prevention. Sleep and Sleep Disorders.
- National Hurt, Lung, and Blood Institute. What Are Sleep Deprivation and Deficiency?
- The National Sleep Foundation. NATIONAL SLEEP FOUNDATION’S 2022 SLEEP IN AMERICA® POLL: Americans Can Do More During the Day and Night to Improve Sleep.
Show all references
- Centers for Disease Control and Prevention. Heart Attack Symptoms, Risk, and Recovery.