Trouble sleeping? Insomnia symptoms linked to increased risk of stroke, heart attack

November 6, 2019

Science Daily/American Academy of Neurology

People who have trouble sleeping may be more likely to have a stroke, heart attack or other cerebrovascular or cardiovascular diseases, according to a study published in the November 6, 2019, online issue of Neurology®, the medical journal of the American Academy of Neurology.

"These results suggest that if we can target people who are having trouble sleeping with behavioral therapies, it's possible that we could reduce the number of cases of stroke, heart attack and other diseases later down the line," said study author Liming Li, MD, of Peking University in Beijing, China.

The study involved 487,200 people in China with an average age of 51. Participants had no history of stroke or heart disease at the beginning of the study.

Participants were asked if they had any of three symptoms of insomnia at least three days per week: trouble falling asleep or staying asleep; waking up too early in the morning; or trouble staying focused during the day due to poor sleep. A total of 11 percent of the people had difficulty falling asleep or staying asleep; 10 percent reported waking up too early; and 2 percent had trouble staying focused during the day due to poor sleep. The researchers did not determine if the people met the full definition of insomnia.

The people were then followed for an average of about 10 years. During that time, there were 130,032 cases of stroke, heart attack and other similar diseases.

People who had all three symptoms of insomnia were 18 percent more likely to develop these diseases than people who did not have any symptoms. The researchers adjusted for other factors that could affect the risk of stroke or heart disease including alcohol use, smoking, and level of physical activity.

People who had trouble falling asleep or staying asleep were 9 percent more likely to develop stroke or heart disease than people who did not have this trouble. Of the 55,127 people who had this symptom, 17,650, or 32 percent, had a stroke or heart disease, compared to 112,382, or 26 percent, of the 432,073 people who did not have this symptom of insomnia.

People who woke up too early in the morning and could not get back to sleep were 7 percent more likely to develop these diseases than people who did not have that problem. And people who reported that they had trouble staying focused during the day due to poor sleep were 13 percent more likely to develop these diseases than people who did not have that symptom.

"The link between insomnia symptoms and these diseases was even stronger in younger adults and people who did not have high blood pressure at the start of the study, so future research should look especially at early detection and interventions aimed at these groups," Li said.

Li noted that the study does not show cause and effect between the insomnia symptoms and stroke and heart disease. It only shows an association.

A limitation of the study was that people reported their own symptoms of insomnia, so the information may not have been accurate.

Also, the researchers did not ask participants about having sleep that was not refreshing; this is another common symptom of insomnia.

https://www.sciencedaily.com/releases/2019/11/191106162539.htm

Insomnia tied to higher risk of heart disease and stroke

August 19, 2019

Science Daily/American Heart Association

Data from more than a million people found that genetic liability to insomnia may increase the risk of coronary artery disease, heart failure and stroke. Among types of ischemic stroke, genetic liability to insomnia was primarily associated with an increased risk of large artery stroke.

People suffering from insomnia may have an increased risk of coronary artery disease, heart failure and stroke, according to new research in the American Heart Association's journal Circulation.

Previous observational studies have found an association between insomnia, which affects up to 30% of the general population, and an increased risk of developing heart disease and stroke. These observational studies were unable to determine whether insomnia is a cause, or if it is just associated with them, explained Susanna Larsson, Ph.D., lead study author and associate professor of cardiovascular and nutritional epidemiology at Karolinska Institutet in Stockholm, Sweden.

In this first-of-its-kind study on insomnia, Larsson and a colleague applied Mendelian randomization, a technique that uses genetic variants known to be connected with a potential risk factor, such as insomnia, to reduce bias in the results. The 1.3 million participants with or without heart disease and stroke were drawn from four major public studies and groups.

Researchers found genetic variants for insomnia were associated with significantly higher odds of coronary artery disease, heart failure and ischemic stroke -- particularly large artery stroke, but not atrial fibrillation.

"It's important to identify the underlying reason for insomnia and treat it," Larsson said. "Sleep is a behavior that can be changed by new habits and stress management."

A limitation to this study is that the results represent a genetic variant link to insomnia rather than insomnia itself. According to Larsson, it was not possible to determine whether or not the individuals with cardiovascular disease had insomnia.

https://www.sciencedaily.com/releases/2019/08/190819082451.htm

Insomnia is a likely long-term side effect of stroke

May 30, 2018

Science Daily/University of Surrey

Stroke patients experience sustained problems with insomnia potentially reducing their ability to relearn key skills and putting them at increased risk of depression, a new study finds.

In the first study of its kind, researchers from the University of Surrey, University of Freiburg, Germany, and the University of Bern, Switzerland, conducted an in depth sleep laboratory experiment to compare the brain signals of patients in the chronic state (at least one year post-stroke) and the general population.

Difficulties with sleeping in those who had a stroke have long been reported but little is known about the brain signals underlying poor sleep, in particular when patients are back in the community. It is also unclear how sleeping poorly during the night relates to sleepiness and fatigue during the day.

Using a polysomnogram (PSG) test, which assesses the brains' sleeping patterns over two nights, researchers found that it took stroke patients longer to fall asleep and that they had poorer sleep efficiency -- the ratio of time spent asleep comparted to the time spent in bed -- than those who had not experienced a stroke.

A multiple sleep latency test (MSLT), also showed that stroke patients were less likely to nap or fall asleep during the day to compensate for lost sleep at night. They were, however, more prone to errors in a vigilance test than their counterparts, increasing their risk of cognitive failures or falls.

Importantly researchers found that although sleep efficiency was reduced in patients, total sleep time between the groups was similar, suggesting that lesions in the brains' centres for sleep-wake regulation are unlikely to cause the insomnia. Rather researchers believe that sleep problems experienced by stroke patients are due to a number of contributory factors, such as greater psychological strain, pain and discomfort as well as reduced levels of physical activity.

Annette Sterr, Professor of Cognitive Neuroscience and Neuropsychology at the University of Surrey, said:

"Our research shows that those who have suffered from stroke maintain difficulties with their sleep which is likely to affect the overall recovery and quality of life. The importance of sleep in aiding the recovery of patients should not be underestimated in helping to improve and maintain physical and mental wellbeing.

"Presently sleep is not considered in the NICE guidelines for stroke rehabilitation, an issue we hope will be revisited by the organisation in due course. Harnessing the power of good sleep is likely to maximise recovery and quality of life."

https://www.sciencedaily.com/releases/2018/05/180530113136.htm