Treatment and comorbidities of multiple sclerosis in an employed population in Japan: analysis of health claims data.

Aim: Use real-world data to investigate the treatment, comorbidities and prevalence of multiple sclerosis (MS) in an employed Japanese population.

Methods: Data from the Japanese Medical Data Center health insurance claims database were analyzed (January 2005-November 2014). Patients with claims associated with an MS diagnosis were identified (n = 494) and comorbidities and prescribed treatments were investigated. MS prevalence within the database was calculated for each calendar year (2011-2013) Results: IFN-β and prednisolone were the most commonly prescribed treatments. Common comorbidities included astigmatism and gastric ulcer. Within the database, MS prevalence increased from 0.015 to 0.016%.

Conclusion: MS prevalence increased from 2011 to 2013. Some comorbidities were considered unrelated to MS owing to how physicians use disease codes for reimbursement.