Attention Shift Workers! Why You’re at Greater Risk for Multiple Sclerosis

For decades I have found people who work shifts respond very differently to my treatment plans – in fact, I have consistently found them the most difficult to treat. I did not, however, know that the disrupted circadian rhythms put shift workers at greater risk of multiple sclerosis.

In a way, it was no surprise to read an article in the Journal of Occupational and Environmental Medicine called “Rotating night shift work and risk of multiple sclerosis.”

The results of this large-scale nurses study showed that working nights for more than 20 years — and likely beginning such shifts early in a career — carries an almost three times higher risk of a definitive MS diagnosis. That’s HUGE. They also found that occasional, or rotating, night shift work, even if done over a decade, does NOT seem to be directly linked to a higher risk of MS.

Sleep is arguably the most important contributing factor when it comes to the body being able to regulate all of it’s major metabolic functions – this is called the circadian rhythm and it is dependent on the regular exposure to dark and light.

Changes in sleep and waking patterns are known to have an important impact on the circadian rhythm and therefore normal function in every cell in every tissue. Maintaining a healthy 24-hour circadian rhythm is increasingly recognized as an important contributor to overall good health. Growing evidence suggests that people with a disrupted internal or biological clock, who are exposed to light during nighttime hours — such as night-shift workers — are at greater risk of chronic diseases such as cancer, cardiovascular disease, and MS.

The impact of night shift work could explain some immune responses that trigger and support MS progression. Exactly how is not known at this time and needs to be explored more.

Researchers reported that “MS risk tended to increase with a longer history of shift work (20+ years) suggesting that long-term or early career circadian disruption might be critical for MS.”

This is a tough one, because as care givers, we choose the career for the contribution we can make, not the hours. But especially in nursing, it is VERY difficult to find a job without shifts.

I think it’s safe to say that the circadian disturbances found in nurses working shifts applies equally to anyone else who works shifts – in factories, in the airline industry, even academics or students who regularly “burn the midnight oil.”

According to this research the risk of developing MS can be reduced by working occasional or rotating shifts. Or making changes early in the career to avoid shift work.

Beyond avoiding shift work, two key ways to regulate circadian rhythms are:

• Sleep in a completely dark room: No lights or no electronics and black out curtains.
• Maintain a regular sleep/wake cycle throughout the week – even on weekends. I recommend bedtime before 10:30 with between 7-9 hours of sleep.