Functional impairments and disability profile of CNS non-MS inflammatory demyelinating diseases: A hospital-based study

Background: Non-MS CNS inflammatory demyelinating diseases are pathologically primary demyelination caused by immunological injury to oligodendrocytes and as a result are clinically severe and can present either as clinically isolated syndromes or recurrent episodes with residual disability. Methods: A cross-sectional observational study was conducted on 65 patients with different non-MS CNS inflammatory demyelinating diseases to study their course (monophasic or recurrent) and the functional impairments such as extent of fatigue, depression (PHQ9 score), motor disability (EDSS score) and bladder-bowel dysfunction (using bladder and bowel control scores respectively). Respective standard scales were used for paediatric groups. The data was then analysed by appropriate statistical methods and observations recorded. Results: Neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) cases had a monophasic and a recurrent course in comparable frequencies, while ADEM and idiopathic groups were strictly monophasic. Highest EDSS at onset was noted in NMOSD, ADEM and LETM reflecting their disabling nature. EDSS declined significantly (p=0.04) from onset to discharge but idiopathic LETM and NMOSD had residual disability. There was significant fatigue seen in most groups but with no significant association with disease type and recurrence (p =0.44). Depression was also co-prevalent but again had no significant association with disease groups and number of episodes (p =0.66). Bladder-bowel dysfunction was severe and significant (p<0.001) among NMOSD, ADEM and LETM cases. Conclusion: This study showed a significant functional disability experienced by patients of non-MS CNS inflammatory demyelinating diseases in terms of fatigue, depression, motor weakness and bladder-bowel dysfunction; and underscores the need to recognise them early, as the motor disability scores declined significantly at discharge.