People recovering from heart failure should consider improving their sleep regularity, according to a study by Oregon Health & Science University. The research team found that even moderately irregular sleep doubles the risk of another clinical event within six months. The results were published in the journal JACC Advances. A clinical event can be another visit to the emergency room, hospitalization, or even death.

Insufficient Sleep can Affect Heart Health

Heart health is influenced by various lifestyle factors, including sleep, diet, and exercise. Chronic sleep deprivation is a growing public health problem and has been linked to an increased risk of heart attack, stroke, and atrial fibrillation in large-scale population studies. Even a few nights of insufficient sleep promote molecular mechanisms associated with an increased risk of heart problems. Researchers at Uppsala University measured the concentrations of around 90 proteins in the blood and found that many of these proteins, which are associated with increased inflammation, increased during sleep deprivation.

Many of these proteins have already been linked to an increased risk of cardiovascular disease such as heart failure and coronary heart disease. The surprising thing is that these proteins increase in the same way in younger, healthy individuals after just a few nights of sleep deprivation. This means that it is important to emphasize the importance of sleep for cardiovascular health early in life.

How Sleep Regularity and Heart Failure are Related

The current study by Oregon Health & Science University underscores the importance of regular sleep for people with heart failure. “Regular bedtimes and wake-up times are important for overall health,” said lead author Brooke Shafer, Ph.D., a research scientist at the OHSU School of Nursing’s Sleep, Chronobiology, and Health Laboratory. “Our study suggests that regular bedtimes may be particularly important for adults with heart failure.” The researchers enrolled 32 patients who had been hospitalized for acute heart failure at OHSU Hospital and Hillsboro Medical Center between September 2022 and October 2023. For one week after their discharge from the hospital, participants kept sleep diaries in which they recorded the time they fell asleep at night, woke up in the morning, and took naps during the day. Participants were then divided into two groups based on their sleep habits: regular sleepers and moderately irregular sleepers.

The study found that after discharge from the hospital, 21 subjects experienced a clinical event within six months. Of this group, 13 were classified as moderately irregular sleepers, while eight had a regular sleep pattern. Statistically, irregular sleepers had more than twice the risk of an event over the six-month period. The increased risk of a clinical event in moderately irregular sleepers remained even when potential confounding factors such as sleep disorders and other underlying conditions were taken into account.

The research team says the study is one of the first to examine the influence of sleep regularity in relation to heart failure, and that the findings add to a growing body of evidence pointing to the importance of a regular sleep schedule. “Improving sleep regularity could be a low-cost therapeutic approach to mitigating adverse events in adults with heart failure,” the authors conclude. Shafer said the findings confirm the link between sleep regularity and cardiovascular health. The next step would be to expand the research to a larger group of participants and investigate whether improving sleep regularity reduces the risk of further clinical events.