Trauma and the risk of MS

Does trauma cause MS? Did you have a head injury prior to the onset of your MS? #MSBlog #MSResearch

"This is meta-analysis, i.e. the combing of many studies on the same issue, suggests that head injury and other traumas in childhood, increases your chance of developing MS. The increased risk is relatively small  (~40%). Whether this is an association or causation needs further study. One of the issues that always raises its head with these sorts of studies is ascertainment bias; if you have a disease you are more likely to recall events that if you don't have a disease. The other issue is could early or asymptomatic MS predispose you to trauma rather than trauma to MS? It is clear that MS may have a long presymptomatic phase that lasts years. It is conceivable that presymptomatic MS may affect neural pathways that reduce your reflexes and reactions time that leads to an increased risk of MS. All this would need to be studied in more detail. This study raises more questions than it answers, but is of interest nevertheless. My big concern is the medicolegal profession will take this as evidence to laucnh a new tranche of legal cases claiming that trauma causes MS and expecting insurance companies to pay out a lot of money. The legal burden of proof - beyond reasonable doubt - is way below the burden of proof required by scientists."

"If head trauma does trigger MS how does it do it? Does it cause the release of brain proteins or antigens that trigger an autoimmune reaction? Does it open or damage the blood brain barrier allowing autoimmune cells to enter the brain and spinal cord? Does it activate the so called innate immune system in the brain and spinal cord that then triggers the development of autoimmune disease? Questions, questions and more questions."



Epub: Lunny et al. Physical trauma and risk of multiple sclerosis: A systematic review and meta-analysis of observational studies. J Neurol Sci. 2013.

BACKGROUND: We aimed to examine physical trauma as a risk factor for the subsequent diagnosis of MS.

METHODS: We searched for observational studies that evaluated the risk for developing MS after physical trauma that occurred in childhood (≤20years) or "premorbid" (>20years). We performed a meta-analysis using a random effects model.

RESULTS: We identified 1362 individual studies, of which 36 case-control studies and 4 cohort studies met the inclusion criteria for the review. In high quality case-control studies, there were statistically significant associations between those sustaining head trauma in childhood (OR=1.27; 95% CI, 1.12-1.44; p<0.001), premorbid head trauma (OR=1.40; 95% CI, 1.08-1.81; p=0.01), and other traumas during childhood (OR=2.31; 95% CI, 1.06-5.04; p=0.04) and the risk of being diagnosed with MS. In lesser quality studies, there was a statistical association between "other traumas" premorbid and spinal injury premorbid. No association was found between spinal injury during childhood, or fractures and burns at any age and the diagnosis of MS. The pooled OR of four cohort studies looking at premorbid head trauma was not statistically significant.

CONCLUSIONS: The result of the meta-analyses of high quality case-control studies suggests a statistically significant association between premorbid head trauma and the risk for developing MS. However, cohort studies did not. Future prospective studies that define trauma based on validated instruments, and include frequency of traumas per study participant, are needed.

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