Are you familiar with this scenario? You consistently wake up at the same time every morning, get your kids ready, and rush to catch the subway for work. At night, you might stay up until midnight doing laundry or until 1 a.m. to catch up on bills.
Many Americans, approximately one-third of the population, find themselves in a similar situation, getting only five to six hours of sleep on a regular basis, falling short of the recommended seven to eight hours.
However, even a mild and chronic lack of sleep can increase the risk of developing heart disease later in life. Numerous surveys of thousands of individuals have indicated that those with mild but persistent sleep deficits are more prone to heart disease later on compared to those who get adequate sleep.
A Columbia study published in Scientific Reports, focusing on women, now sheds light on what’s happening in the body during chronic mild sleep deprivation.
After just six weeks of reduced sleep, the study reveals that the cells lining our blood vessels are exposed to harmful oxidants. Unlike well-rested cells, those deprived of sleep fail to trigger antioxidant responses to counteract these destructive molecules.
The outcome is inflamed and malfunctioning cells, marking an early stage in the development of cardiovascular disease.
Study leader Sanja Jelic, MD, who serves as the director of the Center for Sleep Medicine at Columbia and is a professor of medicine in the Division of Pulmonary, Allergy, and Critical Care Medicine at Columbia University Vagelos College of Physicians and Surgeons, points out, “This provides some of the initial direct evidence that even mild and chronic sleep deficits can lead to heart disease.”
She adds, “Up until now, we’ve only seen links between sleep and heart health in epidemiological studies, which could be influenced by various factors that are difficult to pinpoint and adjust for. Only randomized controlled studies can definitively determine if this connection is real and identify the specific bodily changes that result from insufficient sleep and could contribute to heart disease.”
Bottom line: Just go to sleep
Many studies on human sleep have primarily focused on the physical effects of severe sleep deprivation over just a few nights. However, this approach doesn’t quite reflect how people typically behave night after night. Most individuals tend to wake up at a consistent time each day but often extend their bedtime by an hour or two,” explains Jelic. “Our aim was to replicate this common sleep pattern seen in adults.”
The researchers in this study screened nearly 1,000 women in Washington Heights and eventually enrolled 35 healthy women who typically enjoyed seven to eight hours of sleep each night and could commit to a 12-week study.
During the first six weeks of the study, these women maintained their usual sleep routines. For the subsequent six weeks, they intentionally delayed their bedtime by 1.5 hours. The accuracy of each participant’s sleep schedule was monitored using wrist-worn sleep trackers.
Bottom line: Just go to sleep
“Numerous issues could find resolution if individuals prioritize getting a solid seven to eight hours of sleep each night,” emphasizes Jelic.
“It’s essential for young, healthy individuals to understand that persistent sleep deprivation of less than this recommended duration can heighten their cardiovascular risk.”
Recent epidemiological research indicates that irregular sleep schedules may increase the likelihood of heart disease. Jelic’s research team is actively developing a study to investigate whether inconsistent bedtimes affect vascular cells similarly to the impact of chronic but consistent short sleep.