Sleep Fragmentation May Increase Risk of Inflammation and Atherosclerosis

Atherosclerosis is an inflammatory disease within the arterial wall that can lead to adverse vascular events, including coronary artery disease, myocardial infraction, stroke and peripheral artery disease. According to a new study, sleep disruption may increase the risk of atherosclerosis by raising inflammatory-related white blood cell counts. Sleep fragmentation is repeated, short sleep interruptions during the night which leads to excessive tiredness during the day.

Participants in the study included 1,110 adults with an average age of 68. Sleep fragmentation was measured using sleep lab-based polysomnography and a wrist-based actigraphy worn by participants on multiple nights. Blood samples were taken to measure levels of neutrophils and monocytes, two types of inflammatory-related white blood cells. 

The researchers found that sleep fragmentation resulted in higher neutrophil counts and higher coronary artery calcium scores. Coronary artery calcium scores are used to measure the progression of atherosclerosis. They also found that the increase in neutrophils was directly associated with the increase in coronary artery calcium scores. 

The study was conducted by researchers from the University of California Berkeley. It was published online ahead of print on June 4, 2020 in the journal PLOS Biology.