Associations between onset age and disability in multiple sclerosis patients studied using MSSS and a progression model

• DOI: 10.1016/j.msard.2014.06.002
• Publication Date: 2014-06-24T01:30:49Z
• Authors: Sudarshan Ramacha...; Richard C. Strange; Peter W. Jones; Seema Kalra; Devaki Nayak; Clive P. Hawkins
• Keywords: Adult; Male; Models, Statistical; Multiple Sclerosis; Adolescent; Incidence; Statistics as Topic; Reproducibility of Results; Middle Aged; Prognosis; Risk Assessment; Sensitivity and Specificity; Severity of Illness Index; Disability Evaluation; 03 medical and health sciences; Age Distribution; 0302 clinical medicine; Humans; Computer Simulation; Female; Age of Onset; Sex Distribution; 10. No inequality

While many factors have been examined, male gender and older age at multiple sclerosis onset are among few variables consistently associated with increased disability. Interestingly, the association between onset age and disability may not be linear with some data suggesting a faster rate of accumulation of disability in patients aged more than 30 years at onset.Explore the relationship between onset age and disability.We studied 500 MS patients grouped by cut-offs in onset age. Disability was assessed using Multiple Sclerosis Severity Scale (MSSS) and, a model based on time to reach an Extended Disability Severity Score (EDSS) (progression model). Data were analyzed using linear and logistic regression.The association between disability (assessed by both MSSS and the progression model) and onset age was different in patients whose MS onset occurred after an age band of 30-35 years. Before this age range, changing age was not associated with changes in disability while during and after this age range, disability was increased.We found a significant change in the relationship between disability and onset age after about 31 years supporting the idea that while onset age does not define a sharp cut-off, it can help define subgroups of patients with differing rates of accumulation of disability.