(NEW YORK) — Insomnia may be linked to an increased risk of stroke, dementia and several mental health conditions, a new study finds.
Researchers from Austria, Germany, Italy and Switzerland analyzed approximately 20 comprehensive review studies, involving millions of participants across multiple countries, to evaluate the impact of insomnia on health.
The study, published Sunday in the journal Sleep Medicine Reviews, found that insomnia was linked to a 26% increased risk of stroke.
The results, which looked at multiple other studies also showed individuals with insomnia were more likely to have depression and attempted suicide compared to those without insomnia.
Insomnia, the most common sleep disorder in the United States, makes it difficult to fall asleep, stay asleep or get good quality sleep, according to the National Institutes of Health (NIH).
Researchers also found that people with insomnia had nearly 30% higher odds of being hospitalized for any number of reasons.
“Insomnia deserves attention as a warning sign of the status of brain and mental health,” Luca Vignatelli, lead study author and senior researcher at the IRCCS Institute of Neurological Sciences in Bologna, Italy, told ABC News.
Issues with sleep are often overlooked when addressing mental health concerns, experts told ABC News.
“When you have anxiety or depression, it makes it difficult to fall or stay asleep, or it gives you poor sleep. But then when you don’t sleep well, it increases that risk of anxiety and depression,” Dr. Thanuja Hamilton, a board-certified sleep medicine physician at Advocare, told ABC News. “When you don’t sleep well, you’re more irritable, you’re more anxious, you’re less resilient to stress, and so you’re vulnerable to depression and anxiety, and that can make it harder to sleep.”
Researchers also found a connection between insomnia and dementia, particularly Alzheimer’s disease.
Sleep has been shown to play an important role in clearing waste products linked to impaired brain function and Alzheimer’s disease from the brain, according to the NIH.
“When you sleep, that’s when your brain takes out the trash,” Hamilton said, referring to waste products that can accumulate throughout the day. “If you’re not getting good quality sleep or enough of it, then you’re going to have an excess buildup, increasing that risk of dementia down the line.”
Researchers cautioned that the new findings only show associations and do not prove that insomnia directly causes the health problems examined.
“I would like to emphasize that people should not be frightened by these results. An increased risk at the population level does not mean that an individual with insomnia will develop dementia, depression or have a stroke,” Dr. Stefan Seidel, one of the study authors and professor of neurology at the Medical University of Vienna, told ABC News. “Instead, the findings give us another reason to take persistent sleep problems seriously, identify possible underlying causes and provide evidence-based treatment when appropriate.”
What can people do to improve their sleep?
Habits like making your bed daily, keeping the room cooler and turning off the lights before bed can help improve your sleep, according to experts.
One of the most important healthy sleep habits, they say, is maintaining a consistent sleep schedule.
“Our circadian rhythm, our internal clock, it likes consistency,” Hamilton said. “If you are inconsistent with your sleep, then you confuse your brain. It doesn’t know when to start sleep or when to stop sleep.”
To support healthier sleep, turn off distractions such as the TV or your phone approximately 30 to 60 minutes before bedtime and avoid consuming coffee or alcohol late.
“You go down that rabbit hole when you get on the phone,” Hamilton noted. “It might distract you, but it’s not relaxing you.”
People with insomnia can also become anxious about whether they will be able to fall asleep, potentially making the problem worse.
“The harder you try to sleep when you have insomnia, the harder it is to sleep,” Hamilton added.
Cognitive behavioral therapy (CBT) is often the first treatment option for long-term insomnia. CBT focuses on changing thoughts and behaviors that can interfere with sleep and can include techniques such as adjusting sleep schedules and limiting the amount of time spent awake in bed, according to the NIH.
“The gold standard of treatment for insomnia is CBT, but it’s difficult and it’s time-consuming and it’s a lot of effort, especially for someone with chronic insomnia,” Hamilton said. “But it is worth it.”
Experts say sleep should become a more routine part of conversations about overall health.
“Sleep should be a topic to discuss with your doctor when talking about health, at any age,” Vignatelli said. “We need to raise public awareness about insomnia and its treatment and ensure that sleep is included in health promotion programs in our communities, schools, and workplaces.”
If you or someone you know is having thoughts of suicide — free, confidential help is available 24 hours a day, 7 days a week. Call or text the national lifeline at 988.
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