Too little sleep 'can increase heart-attack risk'
Getting too little sleep can dramatically increase the risk of potentially fatal heart conditions in people with high blood pressure, a study has found.
In some cases sleeping for less than seven and a half hours a night quadrupled the chances of suffering a heart attack, stroke, or “sudden cardiac death”, said researchers.
Scientists in Japan studied 1,255 patients with high blood pressure over an average period of 23 months. Participants were aged between 33 and 97, with an average age of 70.
Of the total, 1,007 slept for more than 7.5 hours a night and 248 for less.
Getting under 7.5 hours of sleep was associated with a 27% increase in risk for patients whose blood pressure did not rise at night.
But it was far more hazardous for the minority of patients who did experience overnight blood pressure increases.
Their likelihood of experiencing a heart attack or stroke, or dying suddenly because of a fatally irregular heart rhythm, more than quadrupled when they slept less than 7.5 hours. However, only 20 patients fell into this category.
Dr Kazuo Eguchi, from Jichi Medical University in Tochigi, Japan, and colleagues wrote in the journal Archives of Internal Medicine: “Reflecting changing lifestyles, people are sleeping less in modern societies.
“A good sleep of adequate duration is essential because sleep fragmentation and sleep deprivation, commonly seen in contemporary society, are associated with multiple health disorders, including cardiovascular diseases (CVD).”
Short sleep duration and a “riser pattern” of overnight blood pressure appeared to interact to increase the risk of heart events, said the researchers.
“It is a relatively small group of individuals who have this combination, and thus it is a group that could be easily identified and monitored more closely,” they wrote.
The scientists pointed out that most of those taking part in the study were elderly and the results may not apply to younger populations the same way.
