Elderly people who don’t sleep well could be at greater risk of strokes, according to new study data.

Spanish researchers analyzed data from 394 people, aged 70 to 100, over a six-year period. They found that elderly people with severe sleep apnea are twice as likely to suffer a stroke than people with mild sleep apnea or none. But scientists insist that there are treatment options available.

Sleep apnea is two to three times more common in the elderly compared to middle-aged individuals.