Background: Studies have documented reduced work capacity and work productivity loss in multiple sclerosis (MS). Little is known about the longitudinal trajectories of work productivity in MS.

Objectives: To examine trajectories of work productivity in people living with multiple sclerosis (PwMS) and the factors associated with the trajectories.

Methods: Study participants were employed participants of the Australian MS Longitudinal Study (AMSLS) followed from 2015 to 2019 with at least two repeated measures (n=2121). We used group-based trajectory modelling to identify unique work productivity trajectories in PwMS.

Results: We identified three distinct trajectories of work productivity: 'moderately reduced' (17.0% of participants) with a mean work productivity level of 47.6% in 2015 (slope -0.97% per year (p= 0.22)), 'mildly reduced' (46.7%) with a mean work productivity of 86.3% in 2015 (slope 0.70% per year (p=0.12)), and 'full' (36.3%) with a mean work productivity of 99.7% in 2015 (slope 0.29% per year (p= 0.30)). Higher education level, higher disability, and higher MS symptom severity are associated with increased probability of being in a worse work productivity trajectory.

Conclusion: We identified three distinct work productivity trajectories in PwMS which were stable over time and differentiated by their baseline level of work productivity.