Medical history risk factors in primary progressive multiple sclerosis: A case-control study

Background: The association between medical history and primary progressive multiple sclerosis (PPMS) development has not been well documented in the pertinent literature. The possible association between 23 medical diseases and PPMS occurrence was assessed in the present study. Methods: In order to figure out the possible association between several medical histories and PPMS occurrence, the present population-based case-control study examined 143 PPMS cases in Tehran, Iran, from 2019 to 2020. Diagnosis of PPMS was confirmed by neurologists based on the 2017 McDonald criteria. Sex-matched healthy controls (n = 143) were selected using the random-digit dialing (RDD) technique. Face-to-face and telephone interviews were conducted for gathering the data. The conditional logistic regression model was used to calculate adjusted and unadjusted odds ratio (OR) at a 95% confidence interval (CI). Results: A significant association was found between PPMS development and diseases like depression (OR = 3.12, 95% CI: 1.49-6.53), migraine (OR = 0.19, 95% CI: 0.05-0.67), infectious mononucleosis (OR = 13.16, 95% CI: 2.74-63.17), hypothyroidism (OR = 3.20, 95% CI: 1.23-8.30), and kidney failure (OR = 3.76, 95% CI: 1.41-9.99). Conclusion: Lifetime history of depression, infectious mononucleosis, hypothyroidism, and kidney failure might increase the risk of PPMS development, while individuals with positive history of migraine disease are at lower risk for developing PPMS.