Multiple sclerosis risk increases with shift work due to circadian rhythm and sleep pattern disruption

Multiple sclerosis (MS) risk increases with shift work due to circadian rhythm and sleep pattern disruption. The study came from Swedish researchers who uncovered an association between multiple sclerosis and shift work. The researchers found that those who engage in off-hour employment prior to the age of 20 are at a greater risk of developing multiple sclerosis as a result of their circadian rhythm disruption.

Previous research has associated shift work with cardiovascular disease, thyroid disorders, and cancer. Shift work is associated with disturbed melatonin secretion and an increase in inflammatory responses, which can promote disease. An autoimmune disease, multiple sclerosis is related to the nervous system, and environmental factors may play an important role in the onset of the condition

The researchers examined the data from two population-based studies and compared the occurrence of multiple sclerosis among those exposed to shift work against those who have never been exposed to shift work.

Lead researcher Dr. Anna Karin Hedström said, “Our analysis revealed a significant association between working shift at a young age and occurrence of MS. Given the association was observed in two independent studies strongly supports a true relationship between shift work and disease risk.” Results showed that those in the incident MS cohort who had worked off-hour shifts for three years or longer before age 20 had a 2 fold-risk of developing MS compared with those who never worked shifts. Similarly, subjects in the prevalent cohort who engaged in shift work as teens had slightly more than a 2-fold risk of MS than subjects who never worked shifts.”

The researchers suggest that disruption of a person’s circadian rhythm may play a role in the development of multiple sclerosis, but additional research is required to determine the exact underlying mechanisms.

Key factors that increase your multiple sclerosis risk

Multiple sclerosis is an autoimmune disease, and like with many autoimmune diseases, the exact cause of the condition is unknown. There are factors that may contribute to a person’s risk of developing multiple sclerosis. Some of these risk factors include:

Genetics: Multiple sclerosis seems to run in families.
Viruses: Some viruses, such as Epstein-Barr virus (EBV), have been linked to the development of multiple sclerosis.
Geography: Populations that live furthest from the equator or in areas with little sunlight exposure have higher prevalence of multiple sclerosis.
Diet: Some dietary factors may contribute to multiple sclerosis, including low levels of vitamin D. On the other hand, caffeine, green tea, and tart cherries have been shown to reduce the risk of multiple sclerosis.

Some of these risk factors cannot be changed, but others, like geography and diet, are modifiable, meaning you can actively work to improve them as a means of reducing your risk of multiple sclerosis.

Furthermore, as the above study reveals, it may be wise to avoid shift work if possible, as that can contribute to a higher risk of multiple sclerosis, too.