Wednesday, October 19, 2011

MS Risk and Teenage Shift Workers

"Shift Work at Young Age is Associated with Increased Risk for Multiple Sclerosis”

That’s the title of a report which will be published in the November Annals of Neurology.  Researchers analyzed information derived from two epidemiological studies in Sweden, examining environmental and genetic risk factors for multiple sclerosis.

The first study, Epidemiological Investigation of Multiple Sclerosis (EIMS), involved completed questionnaires from 1343 MS patients and 2900 case controls.  Mean age for disease onset was 33.4 years and mean time to diagnosis was 1.0 year.  The second study, Genes and Environment in Multiple Sclerosis (GEMS), comprised 5129 cases with MS and 4509 matched controls.  Mean age for disease onset was 33.0 years.  These studies did not have any overlap in participants.

Sleep deprivation is also associated with an increase in pro-inflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-a).  IL-6 induces the development of Th17 cells which have been shown to play a crucial role in the development of autoimmune diseases such as rheumatoid arthritis and experimental autoimmune encephalomyelitis.  Also, significantly increased levels of IL-17 have been seen in MS patients as compared to healthy individuals.  

What was seen in the data is evidence that the longer duration of shift work a person experienced before the age of 20 demonstrated a greater increase in MS risk.  Researchers stratified the risk between less than three years and three years or more.  In EIMS, the odds for developing MS increased to 2:1 in persons who worked shifts for more than three years.  In GEMS, the corresponding odds were 2.1:1, which is noticeably different than the 1.1:1 odds ratio for less than three years of shift work before the age of 20 found in the GEMS study.

Read this post in its entirety:

Teenagers Working Late Nights May Have Increased Risk of Developing MS


  1. Did this come out of ECTRIMS? If you remember it was about a year ago that I posted an entry about thyroid and MS from ECTRIMS that also mentioned an association between RA and MS which you picked up on immediately. ... For all the millions raised for MS research in the US why does it seem Europeans are always a step ahead?

    Caregivingly Yours, Patrick

  2. Hi Patrick,

    I'm not sure if this report will be presented at ECTRIMS. I am on a mailing list from Wiley publishing and received a notice that the embargo had been broken and was thus lifted.

    The email offered a pdf of the study to those who were interested in having it. I asked and received a copy of the report/study. Cool.

    It is interesting that some of the most interesting studies come from Europeans. Perhaps just the fact that several countries actually have MS registries kinda helps things out a bit.