Research Highlights Early Life Factors in Multiple Sclerosis Development

Recent investigations conducted by researchers from the University Medical Center Hamburg-Eppendorf and Heidelberg University Hospital have shed light on potential risk factors for multiple sclerosis (MS) during childhood and adolescence, as part of the extensive German National Cohort (NAKO) study.

Published in the journal Deutsches Ärzteblatt International, the analysis identifies key contributors that may elevate the risk of developing MS, including frequent childhood infections, significant stressful life events, the maternal age at first childbirth, and low levels of physical activity. The research also reaffirmed several established risk factors associated with the disease.

MS is a debilitating inflammatory condition affecting the central nervous system, often leading to a diminished quality of life for those impacted. Despite advances in understanding MS, its exact causes remain largely unknown. Previous studies suggest that both environmental and lifestyle factors may trigger disease onset in genetically predisposed individuals. Known risk factors for MS include genetic predisposition, Epstein-Barr virus infection, vitamin D deficiency, smoking, and obesity. However, the impact of childhood and adolescent experiences has not been extensively explored until now, according to Professor Heiko Becher from the Institute of Global Health at Heidelberg University Hospital.

The study utilized a case-control design within the NAKO framework, involving participants diagnosed with MS alongside a control group without the disease. Participants provided information regarding various risk factors, focusing on prenatal influences, childhood infections, outdoor activity levels, physical exercise during teenage years, body mass index (BMI) at age 18, stressful events, and smoking habits.

In total, the study analyzed data from 576 individuals with medically confirmed MS (396 women and 180 men) and 895 control subjects (638 women and 257 men) matched by year of birth, sex, and study center. Statistical models were employed to determine the correlation between various factors and the risk of MS.

The findings revealed several associations between MS and specific childhood experiences. For instance, the risk of MS increased with each additional childhood infection (odds ratio of 1.14), as well as with each stressful life event (odds ratio of 1.25). Notably, individuals born to mothers aged 30 or older had more than double the risk of MS (odds ratio of 2.11). Conversely, higher levels of physical activity during adolescence were linked to a reduced risk of developing the disease (odds ratio of 0.82).

Additionally, the study confirmed previously recognized risk factors, such as family history of MS, Epstein-Barr virus infection, and being overweight during childhood and adolescence. However, no significant associations were found for other factors analyzed, including serious illnesses (other than MS), exposure to passive smoking during childhood, or the amount of time spent outdoors.

The results emphasize the importance of preventive measures applicable to other non-communicable diseases, such as initiatives aimed at reducing childhood infections, promoting healthy dietary habits, and encouraging physical activity. Anja Holz, the lead researcher from the Institute of Medical Biometry and Epidemiology at UKE, noted that these strategies could also be effective in MS prevention efforts. For instance, emerging evidence suggests that regular exercise in adulthood may serve as a protective factor against MS, advocating for targeted physical activity programs in adolescence to potentially lower MS risk.

Furthermore, the research lays a foundation for future studies to explore the extent to which these newly identified risk factors relate to the severity of MS.

For more information, refer to the study titled Findings of a case-control study nested within the German National Cohort (NAKO) study, published in Deutsches Ärzteblatt International.