Sleep and stroke – where’s the connection?

In a previous post, I’ve discussed about how lack of sleep can adversely affect women’s hearts much more than men’s.

In another study on sleep, too much or too little sleep seems to increase the risk of ischemic stroke among postmenopausal women.

The researchers conducted this prospective study involving 93,175 postmenopausal women aged 50 to 79 years in order to examine link between risk of ischemic stroke and self-reported sleep duration. Ischemic stroke is the most common type of stroke and it occurs when an artery supplying blood to the brain is blocked. The participants were followed up for an average time of 7.5 years, during which 1,166 cases of ischemic stroke were reported among the study participants. 8.3% of the women reported getting less than 6 hours of sleep per night while 4.6% get more than 9 hours of nightly sleep.

Analysis of the data showed that women who slept seven hours a night had lowest risk for stroke. In comparison,

“women who slept nine hours or more had a 70% higher risk of stroke. Those who slept less than six hours per night had a 14% higher risk of stroke. These findings took into account age, race, socioeconomic status, depression, smoking, exercise, use of hormone therapy, and cardiovascular risk factors such as past history or stroke or heart attack, high blood pressure, and diabetes.”

The health risks of lack of sleep are quite well-known but very little is known about the effects of getting too much sleep. This study showed surprising results wherein too much sleep in linked to higher risk of stroke than too little sleep. However, more women reported getting too little sleep than getting too much sleep (8.3 vs. 4.6%). Therefore, the health risks of lack of sleep should not be underestimated.

It is not clear why longer sleep duration increases the risk for stroke and this should be addressed by in future studies. For example, such link should also be investigated among younger women and men.

In another study, midlife stroke has been found to be more common among women aged 45 to 54 years old than men of the same age group. High blood pressure, high cholesterol levels, and weight problems were all identified as possible risk factors. Sleeping pattern would probably be added to this list.

Poor sleep among women seems to be very common and has been linked to physiological and psychological causes. Recent studies have shown that sleeping problems especially increase during the menopausal transition. The American Academy of Sleep Medicine (AASM) is a good source of information about sleep.

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