부산대학교 도서관

Abstract Background A significant proportion of individuals with suspicious onset of multiple sclerosis (MS) does not fulfill the diagnostic criteria. Although some receive other diagnoses, many remain undiagnosed and lack healthcare follow‐up. This study aimed to characterize persons with undetermined diagnosis (PwUD) through a questionnaire. Methods Incident cases with suspected MS were consecutively admitted to a tertiary neurological healthcare center in a prospective cohort study. Those who remained undiagnosed after 40 months (mean, range 31–52) were considered PwUD. They completed a modified questionnaire, previously used in a population‐based case‐control study of incident MS cases. Their responses were compared with two control cohorts, persons with MS (PwMS) and healthy controls, randomly selected from national registries, matched by age, gender, and area of residence. Results Out of 271 patients with suspected MS onset, 72 (20.3%) were PwUD with a female majority (79%). The response rate was 83% and 39% reported persisting MS‐like symptoms. Compared to controls (n = 548) and PwMS (n = 277), fewer PwUD were currently smoking (p = .4 and p = .03), consumed less alcohol (p = .04 and p = .01), and had children (p = .02 and p = .002). PwUD reported occurrence of other autoimmune disease in 29%, higher compared to PwMS and controls (p