Multicentric clinical and epidemiological comparison of neuromyelitis optica spectrum disorder with multiple sclerosis from India

•A total of 212 patients, 166 (78.3%) with MS and 46 (21.7%) with NMOSD, were included from six different cities across india.•Patients with NMOSD were more disabled with a high progression index of 5.99 vs 0.74 respectively (p = 0.02). PI of ≥ 0.39, the LR of having NMOSD was 1.32 (95% CI 1.06–1.64).•Relapsing optico-spinal syndrome (optic neuritis with myelitis) was more common in NMOSD (39.1% vs 0.8%).•One T2 lesion in the last available MRI brain (78.6% vs 39.1%) and at least one gadolinium enhancing lesion in brain MRI documented during course of illness (30.2% vs 8.7%) was more in MS patients.•It is important to distinguish early in the course NMOSD from MS as timely specific treatment may prevent future disability.