Night shift risk for teens

Young adults who work night shifts may face a doubled risk of developing multiple sclerosis, researchers reported last night.

A study from Sweden says the link affects people who worked nights for three years before the age of 20.

The findings, reported in the journal Annals of Neurology, come from an analysis of two groups of people with multiple sclerosis. One group number 1,343 and the other 2,900.

The researchers say a possible explanation is disruption of circadian rhythms and loss of sleep.

However another possible explanation is that shift workers rarely see daylight during the dark Scandinavian winter. The development of multiple sclerosis has also been linked to lack of exposure to sunlight and deficiencies of vitamin D, which is generated by sunlight.

Researcher Dr Anna Karin Hedström, from the Karolinska Institutet, Stockholm, 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.”

Shift Work at Young Age is Associated with Increased Risk for Multiple Sclerosis. Anna Karin Hedström, Torbjörn Åkerstedt, Jan Hillert, Tomas Olsson and Lars Alfredsson. Annals of Neurology October 18, 2011; DOI:10.1002/ana.22597