There is a link between working night shifts and increased risk of multiple sclerosis (MS) in teenagers, Swedish researchers say. A new study suggests that people younger than aged 20 years employed in night shifts experience disruptions in their circadian rhythm and sleep-pattern, which potentially heightens their risk of developing MS.

Anna Karin Hedstrom, MD, Karolinska Institiuet in Stockholm, Sweden, led the study and analyzed data yielded from two population-based studies among Swedish residents aged 16 years to 70 years. The first study encompassed 1,343 MS cases with 2,900 controls. The second study involved 5,129 prevalent MS cases and 4,509 controls. Study participants working night shifts with averaged hours between 9 p.m. and 7 a.m. Researchers say they compared the occurrence of MS in participants who maintained these working hours to the occurrence of MS in patients who worked during daytime hours.

The researchers reported that participants working a night shift for 3 years or more before their 20th birthday were twice as likely to develop MS compared to those who worked daytime jobs. Similar results were observed the second study. ìOur analysis revealed a significant association between working [night] shifts at a young age and occurrence of MS. Given the association was observed in two independent studies strongly supports a true relationship between [night] shift work and disease risk, Hedstrom says.

The authors of the study emphasize a potential association with disruption of circadian rhythm and sleep loss with the development of MS. However, researchers say further studies are necessary to determine the precise process that leads to the increased risk.


Source: Karolinska Institiuet