March 6, 2013
Insomnia Associated With Threefold Increase In Heart Failure Risk
Michael Harper for redOrbit.com — Your Universe Online
Those who have trouble falling asleep at night might have one more thing to cause them grief. According to a new study published in the European Heart Journal, people who experience symptoms of insomnia are three times more likely to suffer from heart failure.
This study, the largest of its kind to date, followed 54,279 people for more than 11 years. Though researchers were able to identify a link between insomnia and heart failure, they said they aren´t fully convinced that there exists a direct correlation between the two.
For the study, Dr. Lars Laugsand, a post-doctoral fellow in the Department of Public Health at the Norwegian University of Science and Technology (NTNU), observed patients who had enrolled in the Nord-Trondelag Health study (HUNT) between 1995 and 1997.
Those patients who reported having trouble falling asleep, staying asleep and waking up feeling unrefreshed – three major symptoms indicative of insomnia – were three times more likely to develop heart failure by the time the study was completed in 2008.
“We do not know whether heart failure is really caused by insomnia, but if it is, insomnia is a potentially treatable condition,” said Dr. Laugsand in a statement.
Insomnia can be triggered by some unhealthy traits and behaviors, such as living a sedentary lifestyle, smoking and obesity. These factors have also been found to increase a person´s risk of heart disease and heart failure.
Yet, when Dr. Laugsand and his colleagues adjusted the results to account for these factors, the results were the same.
When high anxiety was considered, the results were even greater; the participants were four times more likely to experience heart failure.
Speaking with the BBC, Dr. Laugsand said this study has at best shown a casual link between insomnia and heart failure.
That insomnia is so treatable is cause enough for sufferers to seek treatment to avoid any further difficulties. Otherwise, the sleep problem could snowball into anxiety and stress, increasing the risk of heart failure.
"When you have insomnia your body releases stress hormones which in turn may effect the heart in a negative way," said Dr. Laugsand.
Dr. Tim Chico, a senior clinical lecturer at the University of Sheffield is also cautious of the study, agreeing that there may be no causal link between the two health conditions.
“Studies like this raise interesting suggestions that need further work to examine,” said Dr. Chico. "Insomnia is a very unpleasant condition, but there are effective lifestyle changes that can reduce it, such as weight loss and exercise. Luckily many of the things that reduce the chance of heart failure also reduce insomnia - good diet, exercise, weight loss and not smoking."
“It is still unclear why insomnia is linked to higher heart failure risk,” said Dr. Laugsand in a press statement. “We have some indications that there might be a biological cause, and one possible explanation could be that insomnia activates stress responses in the body that might negatively affect heart function. However, further research is also needed to find the possible mechanisms for this association.”