Waking up early may increase your risk of heart attack and stroke, a study in Japan shows.
A one-hour advance in the wake-up time of study participants increased the risk of hardening of the arteries by 1.2 times even without a change in sleep duration, according to the results reported by Mayuko Kadono at Kyoto Prefectural University. The study, which analyzed 3,066 healthy adults averaging 57.2 years old, also found people who had difficulty falling or maintaining sleep at night had a higher prevalence of hypertension.
The analysis underscores Kadono’s previous study that showed links between vascular dysfunction and waking up before 5 a.m. Cardiovascular disease, which includes heart attack, stroke, and high blood pressure, may kill 23.6 million people by 2030, rising from 17.3 million in 2008, according to the World Health Organization.
Earlier bedtimes and earlier wake-up times “had a larger influence on vascular condition than sleep duration,” Kadono, an endocrinologist, said in an interview yesterday. “People generally go to bed earlier and get up earlier as they age. Age-associated changes of rhythm and sleep forms might influence vascular condition.”
The summary of the study didn’t specify participants’ sleeping times and duration. The results were presented at the 6th World Congress of the World Sleep Federation, which opened in Kyoto, Japan, on Oct. 16 and ends today.