Sleep Apnea May Spur Night Heart Attacks
Obstructive Sleep Apnea May Trigger Nighttime Heart Attacks
July 21, 2008 -- Obstructive sleep apnea may
make nighttime heart attacks more likely than daytime heart attacks, a new
In obstructive sleep apnea, the upper airway becomes completely or partially
blocked, interrupting regular breathing, several times per night.
The new study, published in the Journal of the American College of
Cardiology, recommends that people who have heart attacks while sleeping at
night be screened for obstructive sleep apnea.
The study included 92 people who had recently had a heart
The patients reported what time their heart attack symptoms started. They
also took part in a sleep study about 17 days after their heart attack. The
sleep study showed that 64 patients had obstructive sleep apnea.
The patients with and without sleep apnea were pretty similar in their
backgrounds and medication use. But the timing of their heart attacks was
The patients with obstructive sleep apnea were six times more likely to have
had their heart attack between midnight and 6 a.m. than during the rest of the
day. In contrast, the patients without sleep apnea were more likely to have had
their heart attack between 6 a.m. and noon.
Obstructive sleep apnea "may be a trigger" for heart attacks, write the
researchers, who included the Mayo Clinic's Fatima Kuniyoshi, PhD. Kuniyoshi's
team calls for further studies to see if obstructive sleep
apnea treatment reduces heart attack risk, especially at night.