P.97 Clinical differences between ocular and generalized myasthenia gravis

Abstract

Myasthenia gravis (MG) is an autoimmune disease that leads to activity induced weakness in skeletal muscle, which in most cases, are caused by autoantibodies against acetylcholine receptors (AChR). Some patients only have ocular symptoms throughout life (ptosis and diplodia) whereas others have more generalized symptoms such as weakness in extremities and the neck muscles, dysphagia and dysarthria. Not many studies have evaluated whether differences regarding demographics and phenotype separate the two groups of MG patients. Such differences may have consequences for the diagnostic process and management of the disease. Data are collected from an ongoing, retrospective chart review, in which we aim to collect data on 400 patients. Characteristics such as age, gender composition, thymoma status, disease onset and evolution, antibody profile, result of neurophysiological examination, medication, treatment response and satisfaction level are evaluated. By aiming this knowledge, we hope to understand the pathophysiology even better, optimize guidelines and patient satisfaction level. Preliminary results from the first 300 patients suggest that there is a larger time delay from symptom onset until diagnose in the purely ocular group. 21,4% of the ocular patients are diagnosed within two months, where it is 27,8% in the generalized group (p-value=0,57). The average number of MG drugs used to treat the ocular patients are 2,3 drugs compared with 3,2 drugs used to treat the generalized patients (p-value=0,0001). The gender composition is 52,6% women in the ocular group versus 52,7% in the generalized group. The results suggest that it is more difficult to diagnose the ocular patients, but insignificantly less complicated to treat this group. The gender composition seems to be equal in the two groups. More data will be presented in the poster.