Exploring Generational Shifts in Onset Age of Familial Multiple Sclerosis
Multiple sclerosis (MS) is a chronic, potentially debilitating disease affecting the central nervous system, leading to physical and cognitive impairments. Familial MS (fMS), where the condition appears in multiple family members, suggests a strong genetic component in the disease's etiology. A study conducted in Belgrade aimed to explore the prevalence of fMS in the local MS population, differences between familial and sporadic MS cases, and particularly whether there is an "anticipation phenomenon" — the appearance of symptoms at progressively younger ages in successive generations.
Study Overview
The research was spearheaded by a team from the University of Belgrade and other institutions, analyzing data from the Belgrade MS population Registry. This registry includes comprehensive demographic and clinical data, providing a robust base for investigating the familial aggregation of MS and potential anticipation phenomena.
Key Findings
Prevalence of Familial MS:
fMS was identified in 6.4% of the MS population in Belgrade.
The average age at symptom onset was earlier in fMS cases (30.4 years) compared to sporadic MS (32.3 years).
Anticipation Phenomenon:
Younger generations in fMS families experienced an earlier onset of symptoms (average 25.8 years) compared to their older relatives (35.7 years).
This difference persisted even after adjusting for follow-up length, suggesting genuine anticipation.
Clinical Characteristics:
No significant differences were found in gender distribution, disease progression, or MS phenotype between younger and older generations of fMS cases.
Familial cases tended to have a lower disability score (EDSS) at diagnosis compared to sporadic cases, which may indicate earlier detection and possibly more proactive management due to family awareness.
Implications
The presence of anticipation in MS suggests potential genetic mechanisms that may accelerate disease onset in subsequent generations. These findings could influence genetic counseling and early intervention strategies. It also highlights the importance of family history in managing MS, as earlier symptom recognition in familial cases can lead to prompt diagnosis and treatment.
Study Limitations and Strengths
The study's reliance on self-reported symptom onset could introduce recall bias, especially in familial cases where awareness of MS symptoms might be heightened. However, the study's design, which included a well-maintained registry and a comprehensive analytical approach, provided robust data supporting the findings.
Conclusion
This study from Belgrade adds significant evidence to the understanding of familial multiple sclerosis, particularly the anticipation phenomenon. The earlier age of symptom onset in younger generations could have profound implications for diagnosing and managing this challenging condition. Further research is needed to explore the genetic basis of this phenomenon and to confirm these findings in other populations.
Reference:
Jovanovic, A., Pekmezovic, T., Mesaros, S., Novakovic, I., Peterlin, B., Veselinovic, N., ... & Drulovic, J. (2024). Earlier age of symptom onset in younger generation of familial cases of multiple sclerosis. Neurological Sciences, 1-7.
