Medication trajectories among persons with multiple sclerosis in a Quebec birth cohort

Polypharmacy in individuals with multiple sclerosis (MS) is associated with reduced quality of life. There is limited evidence on the long-term use of any medication and its evolution among individuals living with MS in the province of Quebec, Canada.

To identify medication trajectories and describe characteristics of individuals within these trajectories.

In a birth cohort, people with MS were identified from a validated algorithm based on use of health services from 1997 onward. Those covered by public drug insurance during at least three years until 2014 were included. Latent class growth analysis was used.

A total of 551 people with MS were included (74% women, median age at diagnosis 31 years). Four medication trajectories were identified and remained mostly stable over a decade: low (n=143), moderate (n=248), high (n=129) and very high (n=31). Among 443 persons covered by public drug insurance in the post-diagnosis year, the median number of medications by trajectory was: 1 (low, n=107), 4 (moderate, n=201), 7 (high, n=107), and 14.5 medications (very high, n=28), respectively. Female sex, older age at diagnosis, rural place of residence, and greater material deprivation were more common in the very high medication group. People in the high medication trajectories tended to have more MS-healthcare visits with general practitioners but less with neurologists. Central nervous system drugs were the most claimed medications.

Distinct medication trajectories were identified with variation in age at MS diagnosis, sex, residence area and material deprivation across groups.