Despite advances in MRI, the diagnosis of MS is hard for the non-specialist.
A Swiss study recently found that the delay in MS diagnosis is more than 2 years in 40% of PwMS.
Surprised? You should be, because according to this study by 2016-2017 the delay in diagnosis had only improved by half as much since the year 2000!
What is not surprising, however, is that in a majority of instances this delay caused by the co-existence of other chronic disorders. Not an exhaustive list – the major culprits are heart disease, stroke, lung disease, diabetes, cancer, parkinson’s, and even psychiatric illness.
The last is a point of contention for me, as mood issues are more likely to divert the patient away from secondary care than any of the other co-morbidities listed.
Further bolstering these findings, this year at ECTRIMS, the team from Germany presented data showing that PwMS were seeing their doctor for neurological and psychiatric symptoms even years before diagnosis.
Whilst, disorders related to pregnancy and the respiratory system were less often diagnosed during the prodromal phase of MS. One wanders if being pregnant is a protective factor, but speculating on causal effects from this data would be a mistake.
A large exploratory case-control study on the multiple sclerosis prodrome
A. Hapfelmeier, C. Gasperi, E. Donnachie, B. Hemmer
Introduction: Previous studies suggested the existence of a prodromal period before diagnosis of Multiple Sclerosis (MS) based on the analysis of health care data. Findings ranged from increased health care use to increased physician encounters and nervous system-related symptoms. With the present study we pursue several objectives. First, to substantiate and extend the present body of evidence by exploring relations of MS to a large number of diseases using ambulatory claims data. Second, to identify the MS specific prodrome by use of additional control cohorts with other autoimmune diseases. And third, to explore whether effects are age dependent.
Methods: We used the ambulatory claims data of the Bavarian Association of Statutory Health Insurance Physicians (BASHIP), covering the years 2005 to 2017, to investigate the relation between MS (n=12,262) and 1663 diseases that were coded by the International Classification of Diseases (ICD-10) in the five years before first diagnosis of MS. Subjects newly diagnosed with Crohn´s disease (n=19,296), psoriasis (n=112,292) and matched subjects with no history of these autoimmune diseases (n=79,185) served as control cohorts. Statistical analysis was performed by logistic regression models adjusting for age and gender. Sidak’s correction for multiple testing was applied despite the exploratory character of the analyses (α = 0.05). Additional subgroup analyses were performed according to age classes.
Results: Statistical significance was reached for 159 coded diseases after adjustment for multiple testing. Positive relations to MS were found for physician encounters for symptoms related to the nervous and musculoskeletal system and eye. Negative associations were expressed for ICD codes related to pregnancy. Age dependency was observed for the majority of effects.
Conclusions: The various findings obtained from the extensive investigations of a large dataset provide detailed and precise results about the MS prodrome. A comparison to cohorts with other autoimmune diseases further enabled the identification of the MS specific prodrome. Finally, the exploration of age dependent effects deepens our knowledge about the prodromal period and may support the diagnosis of MS in different age classes.