Washington: Teenagers who engage in shift work may be at risk for multiple sclerosis due to a disruption in their circadian rhythm and sleep pattern, Swedish researchers say.
Dr. Anna Karin Hedstrom and colleagues from the Karolinska Institutet in Stockholm analyzed data from two population-based studies—one with 1343 incident cases of MS and 2900 controls and another with 5129 prevalent MS cases and 4509 controls.
The team compared the occurrence of MS among study subjects exposed to shift work at various ages against those who had never been exposed. All study subjects resided in Sweden and were between the ages of 16 and 70. Shift work was defined as permanent or alternating working hours between 9 p.m. and 7 a.m.
The researchers found that those who 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.
The authors suggest that disruption of circadian rhythm and sleep loss may play a role in the development of MS; however the exact mechanisms behind this increased risk remain unclear and further study is needed.
“Our analysis revealed a significant association between working shift at a young age and occurrence of MS,” said Dr. Hedstrom.
“Given the association was observed in two independent studies strongly supports a true relationship between shift work and disease risk,” she added.
The study was recently published in Annals of Neurology.