Poor Sleep Causes Irreversible Negative Effects to Immune Cells, New Evidence Shows

New evidence from a Mount Sinai study suggested that consistent lack of sleep has negative effects on immune stem cells and increases the risk of inflammatory disorders and heart disease. And while it might be thought that a period of inadequate sleep can be amended by catching up on sleep, findings indicated that the cellular effects can’t be reversed.

This study is the first to demonstrate the relationship between sleep and DNA within the immune cells–particularly, that sleep alters the structure of this DNA. Consistently cutting sleep short, even for 90 minutes a night, can lead to increased vulnerability to disease and negative impacts.

“This is important because it is yet another key observation that sleep reduces inflammation and, conversely, that sleep interruption increases inflammation,” Filip Swirski, PhD, Director of the Cardiovascular Research Institute at Icahn Mount Sinai, and lead investigator, said in a statement. “This work emphasizes the importance of adults consistently sleeping seven to eight hours a day to help prevent inflammation and disease, especially for those with underlying medical conditions.”

Does 90 Minutes of Sleep Make a Difference?

Swirski and his team conducted the investigation by evaluating the immune cells of 14 healthy adults who regularly achieved 8 hours of sleep each night and assessed their sleep for a duration of 6 weeks. Investigators continued to analyze their immune cells for the following 6 weeks while participating individuals reduced their sleep duration by 90 minutes each week.

Upon comparison, the team discovered significant changes in the samples of immune cells collected from the periods of full sleep and restricted sleep. At the conclusion of the 12th week, an increased number of immune cells were present in blood samples, due to the lack of sleep.

“This study begins to identify the biological mechanisms that link sleep and immunological health over the long-term,” Swirski stated. “It shows that in humans and mice, disrupted sleep has a profound influence on the programming of immune cells and rate of their production, causing them to lose their protective effects and actually make infections worse—and these changes are long-lasting.”

Poor Sleep Restructures DNA

Investigators also observed an altered DNA structure was present in each participating individual, suggesting that recovering lost sleep time is not able to completely reverse the impact that inadequate sleep has.

“Our findings suggest that sleep recovery is not able to fully reverse the effects of poor-quality sleep,” Cameron McAlpine, PhD, Assistant Professor of Medicine at Icahn Mount Sinai, and co-lead investigator, stated. “We can detect a molecular imprint of insufficient sleep in immune stem cells, even after weeks of recovery sleep. This molecular imprint can cause the cells to respond in inappropriate ways leading to inflammation and disease.”

“It was surprising to find that not all clusters of stem cells responded to insufficient sleep in the same way,” he continued. “There were some stem cell clusters that proliferated and grew in number, while other clusters became smaller. This reduction in overall diversity and aging of the immune stem cell population is an important contributor to inflammatory diseases and cardiovascular disease.”

The study "Sleep exerts lasting effects on hematopoietic stem cell function and diversity" was published in the Journal of Experimental Medicine.