Low Sleep Duration Linked to Higher Risk of Systemic Lupus Erythematosus

May Choi, MD, MPH

The effect of sleep health on disease prevention may have a profound impact when looking at systemic lupus erythematosus (SLE). A large study found an association between chronic low sleep duration and increased risk of SLE.

Sleep deprivation has known associations with risk of autoimmune diseases, but investigators, including May Y. Choi MD, MPH, Brigham and Women’s Hospital and Harvard Medical School, Division of Rheumatology, Department of Medicine, Cumming School of Medicine, University of Calgary, decided to evaluate the relationship between sleep and SLE.

While there have been several small case-control and cohort studies on this relationship, the research yielded conflicting results. Sleep is particularly challenging to examine in individuals with SLE, due to potential confounders and effect modifiers like pain, depression, shift work, and hormonal status, investigators noted.

Evaluating Sleep Duration in Patients with SLE

In the large prospective cohort study, investigators factored in information collected from biennial questionnaires regarding lifestyle, exposure and medical history using the Nurses' Health Study (NHS) and NHSII cohorts. Associations between cumulative average sleep duration and incident SLE were modeled with Adjusted Cox regression analyses.

The study population consisted of 186,072 women with 187 incident SLE cases during a combined 4,246,094 person-years. Women self-reported the total hours of sleep they achieved in a 24-hour period. The cumulative average of sleep duration was identified by the sum of sleep duration for an individual, divided by the number of assessments they participated in.

Those who reported shorter sleep duration also consumed less alcohol and were more likely to engage in regular exercise, as well as have a history of shift work for 6 or more years, and experienced higher bodily pain.Additionally, this group reported a younger age of menarche when compared to women with longer sleep duration.

The Relationship Between SLE Risk and Sleep Duration

Women who chronically slept 5 hours or less per night were associated with increased risk of systemic lupus erythematosus compared with those who slept 7-8 hours or more, even after a 4 year intermission of the analysis and adjustments were made for lifestyle and confounding factors.

Data also revealed interactions between low sleep duration and high bodily pain as well as an interaction between low sleep duration and depression. The association with shift work was less impactful, though trended toward an interaction.

"In conclusion, we found an association between sleep deprivation and SLE risk, potentially exacerbated in those with a history of depression and bodily pain," investigators wrote. "A better understanding of the mechanisms involving the nervous system and immune system that may be underlying the complex interaction between depression, pain, sleep, shift work, and autoimmune disease development is needed. Our findings have implications for SLE prevention and the promotion of adequate sleep duration."

The study, "Association of Sleep Deprivation and the Risk of Developing Systemic Lupus Erythematosus among Women" was published in Arthritis Care & Research.