PTI: Six, seven or
eight -- so how many hours of sleep are enough for you? It's probably
best to aim for seven hours of quality shut-eye every night, says a new
study led by an Indian-origin researcher.
Anoop Shankar and his team at West Virginia University has found that
those who sleep more or less than seven hours a day are at a raised risk
of developing coronary heart disease, the Sleep' journal reported.
They have based their findings on an analysis of data gathered in a
national US study in 2005 on 30,000 adults.
The study found found that the subjects who said they slept nine hours
or longer a day were one-and-a-half times more likely than seven-hour
sleepers to develop heart disease.
And, adults under 60 who slept five hours or fewer a night raised their
risk of developing cardiovascular disease more than threefold compared
to people who sleep seven hours, the study found.
According to the researchers, short sleep duration is associated with
angina, while both sleeping too little and too much are linked to heart
attack and stroke.
The results remained the same after considering age, sex, race, whether
the person smoked or drank, whether they were fat or slim, and whether
they're active or couch potato.
However, the researchers were unable to find out the exact reason
between how long one sleeps and heart disease. But they pointed out
sleep duration affects endocrine and metabolic functions and sleep
deprivation lead to impaired glucose tolerance, reduced insulin
sensitivity and elevated blood pressure, all of which raise risk of
hardening arteries.
Shankar said that doctors should screen for changes in sleep duration
when assessing patients' risk for heart disease and that public health
initiatives consider including a focus on improving sleep quality and
quantity.
