Poor sleep does more damage than simply leaving you tired and irritable the following day. Whether you’re not getting enough total hours of sleep or you’re experiencing frequent nighttime interruptions, over time consistently poor sleep can lead to a number of serious health conditions. One of these health conditions includes putting you at an increased risk of heart disease.

The link between poor sleep and heart disease is especially concerning for women. According to the C.D.C., heart disease is the leading cause of death for women in the U.S., killing nearly 300,000 women a year.

While scientists continue to study the specific reasons sleep and heart disease are so intertwined, an overwhelming amount of research leaves little doubt the two are closely connected. Here’s what you need to know about the sleep and heart disease relationship and why it’s an issue to take seriously — especially for women.

What Is Heart Disease?

It’s worth quickly reviewing heart disease before delving into how it’s linked to sleep.

Heart disease is an umbrella term that covers several heart conditions. These conditions include:

  • Heart failure, where the heart fails to efficiently pump blood throughout the body.
  • Myocardial infarction, better known as a heart attack, where the heart muscle is damaged by interrupted blood flow, typically due to a blood clot.
  • Arrhythmia, or an irregular heartbeat.
  • Coronary artery disease (CAD)

In the U.S., the most common heart disease is coronary artery disease. This occurs when coronary arteries, which supply the heart with oxygen and nutrients, become damaged, usually due to plaque buildup containing cholesterol. As plaque deposits increase, the heart receives less nutrients and oxygen — especially in moments when they’re needed the most, like when exercising.

Symptoms of Heart Disease

The symptoms of heart disease change depending on the particular ailment. Common symptoms, though, include chest pain, shortness of breath, and heart palpitations.

For heart failure, shortness of breath, swelling of the feet, abdomen and neck veins, and fatigue are regular indicators there’s a problem. And for heart attack, symptoms include dizziness, pain in several parts of the body, and profuse sweating, among the other common signs of heart disease.

For more information on symptoms of heart disease, The Mayo Clinic has a useful breakdown.

Risk Factors for Heart Disease

  • Hypertension, or high blood pressure
  • Smoking
  • Diabetes
  • Obesity
  • Poor diet
  • Excessive drinking
  • High blood cholesterol

Women, Heart Disease and Inflammation

Beyond the more well known risk factors for heart disease, let’s discuss the particular reasons women are especially at risk of heart disease when getting insufficient sleep. Poor sleep and increased risk of developing heart problems also affect men, but research has shown a few factors for heart disease are especially linked to women.

For example, researchers from the University of California, San Francisco found poor sleep — and in particular, waking up too early — can lead to increased inflammation for women. The study, looking at nearly 700 men and women in their mid-60s, found men did not suffer from increased inflammation as the female participants did.

What Is Inflammation?

Inflammation occurs when the body releases white blood cells to help combat an affected area; small blood vessels also swell up to allow the white blood cells and proteins to travel to the affected area.

Sleep Problems for Women Lead to Heart Health Issues

This is important because inflammation, over long stretches, is an indicator of heart health problems. The UCSF study found poor sleep played a major role in elevating inflammation to unhealthy levels for women with coronary artery disease.

The study also looked at a number of biomarkers tied to inflammation. After five years, the researchers found poor sleep was strongly associated with a spike in biomarkers in women but not men. The key takeaway: women who said they got either “very poor” or “fairly poor” sleep had 2.5 times more inflammation biomarkers than men who also reported the same sleep quality.

While the study did not answer why women are more prone to inflammation than men due to poor sleep, researchers hypothesized it could be because of lower estrogen levels. (Most of the women in the study were post-menopausal.) Still, the research built on previous studies showing poor sleep quality for women can lead to risk factors tied to heart disease.

Insomnia and Heart Disease

Waking up early isn’t the only sleep issue that can contribute to heart disease. Insomnia, where people have either a hard time falling asleep, or wake up frequently during the night and have a hard time falling back asleep, has been shown to increase the risk of suffering from cardiovascular disease.

One study from 2013, looking at several years worth of data for more than 86,000 women between the ages of 50-79, drove this home. Researchers found women suffering from insomnia carried a 38% higher risk of having congenital heart disease (CHD), which is a problem with the heart’s structure that’s present from birth.

The study also found women suffering from insomnia were at a 27% higher risk of suffering from cardiovascular disease (CV), which is used interchangeably with heart disease. These results were consistent when adjusted for factors like age and race.

Sleep duration, according to the same study, was a prime indicator of these issues.

The less sleep female participants had, the greater likelihood they would suffer from heart disease; women reporting 5 hours of sleep or less each night had “significantly higher” odds of dealing with both congenital heart disease and cardiovascular disease than those who got a normal 7-8 hours of sleep each night. And interestingly, sleeping too much — upwards of 10 hours each night — was also linked to a higher risk of developing both heart problems.

“Sleep duration and insomnia are associated with CHD and CVD risk, and may interact to cause almost double the risk of CHD and CVD,” the study concluded. “Additional research is needed to understand how sleep quality modifies the association between prolonged sleep and cardiovascular outcomes.”

Related: 7 Common Causes of Insomnia

Insufficient Sleep, Diet, and Heart Disease

Researchers continue to investigate how poor sleep duration and quality contributes to heart disease, and a recent study from Columbia University highlighted one key factor bridging the two: diet.

The Columbia study, looking at nearly 500 women, found poor sleep — measured by several indicators, including how long it took to fall asleep and how many nighttime arousals a participant had — was connected to poor eating habits.

Female participants who took longer to fall asleep at night (with sleep latency periods of 60 minutes or more) reported higher caloric intake and also ate more food than women who didn’t have this issue.

Women suffering from severe insomnia symptoms also ate more food, adjusted for weight, and consumed more saturated fats than women who showed little to no signs of insomnia. Poor sleep quality could lead to excessive calorie intake, the Columbia researchers said, by suppressing internal signals of fullness.

How is this connected to heart disease?

It’s because long periods of high calorie intake can lead to obesity, which is a “well-established risk factor for heart disease,” the researchers said.

Obesity has been linked to hypertension, which taxes the heart and can result in heart failure. As people get older, watching their diet is an important safeguard against developing heart disease — and getting an efficient, uninterrupted 7-8 hours of sleep each night provides a great foundation for healthier eating.

The less you stay up late into the night, the less likely you are to answer your urge for a midnight snack — and consequently, the less likely your diet will contribute to heart problems.

How to Fight Poor Sleep

An overwhelming amount of research indicates insufficient sleep duration and poor sleep quality can both lead to an increased risk of heart disease. But just because the connection exists doesn’t mean you have to deal with poor sleep.

If you’ve had a hard time falling asleep of late, try to implement some of the following tips to get better sleep:

  • Avoid caffeine late in the day. That includes caffeine you might find in chocolate and other candy
  • Keep your bedroom cool and well-ventilated to initiate sleep and help you stay asleep
  • Avoid computer screens before bed. The light generated by these screens can interfere with your ability to sleep by interfering with your ability to begin producing melatonin, a hormone that helps you go to sleep
  • Make sure to get plenty of sunshine in the mornings. It will help your body regulate its circadian rhythms and it signals your brain to stop producing melatonin
  • Exercise regularly
  • Alcohol, in excess, and tobacco are unhealthy and both can disrupt sleep. Stop drinking a few hours before bedtime and quit smoking if possible
  • Try a warm bath an hour or two before bed
  • Try using a relaxation technique. Meditation, journaling and positive visualization are all great ways of getting in a relaxed headspace

Likewise, if you’re concerned an underlying sleep disorder like insomnia or sleep apnea could be the reason you’re having a hard time getting good sleep, we’re here to help. Our team of sleep specialists has more than 25 years of experience treating 90 different sleep disorders, so contact Sleep Centers of Middle Tennessee today and see how we can get your sleep back on track.

 

 

References

Prather, A.A., et al. (2013). Gender differences in the prospective associations of self-reported sleep quality with biomarkers of systemic inflammation and coagulation: findings from the heart and soul study. Journal of Psychiatric Research 47(9): 1228-35. Retrieved on May 8, 2020 from:
https://www.ncbi.nlm.nih.gov/pubmed/23746737

Sleep Duration, Insomnia, and Coronary Heart Disease Among Postmenopausal Women in the Women’s Health Initiative. Journal of Women’s Health 22(6): 477-486. Retrieved on May 8, 2020 from:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3678565/

Zuraikat, F., et al. (2020). Measures of poor sleep quality are associated with higher energy intake and poor diet quality in a diverse sample of women from the go red for women strategically focused research network. Journal of the American Heart Association 9(4). Retrieved on May 8, 2020 from:
https://www.ahajournals.org/doi/10.1161/JAHA.119.014587