Researchers at the Mayo Clinic analyzed 10,701 consecutive patients who received a first polysomnography (sleep test) at their institution and who had no history of SCD. After an average followup of 5.3 years, 142 people had either a fatal SCD or were successfully resuscitated. The analysis showed that people who had OSA were at increased risk for SCD and that the most severe cases of OSA had the highest risk for SCD. OSA was found to be associated with SCD even after other well known risk factors for SCD were taken into account.
Low nighttime levels of oxygen in the blood, which the researchers noted is an “important pathophysiological feature of OSA, strongly predicted SCD independently of other well-established risk factors.” The researchers, who previously reported that people with OSA were more likely than the rest of the population to die from cardiac causes at night, concluded that the increase in SCD at night “may represent ‘excess’ deaths, rather than simply a shift of SCD from other times of the day to the night.”
“The prevalence of obstructive sleep apnea in Western populations is high and will likely only continue to grow given the obesity epidemic and direct relationship between obesity and sleep apnea,” said Apoor Gami, lead author of the study, in an ACC press release.
Larry Husten, Contributor