Mortality statistics represent a definitive prognostic measure in MS but are rarely matched with prospective clinical data in life because of the long duration of disease. However, use of contemporary mortality data is essential for economic and clinical models of disease employed to assess long-term outcomes.
2516 MS patients in southeast Wales, of whom 535 have died, were included. Kaplan-Meier survival analysis was used to calculate time to and age at death, and Cox regression to analyse clinical variables associated with age at death. Standardised mortality ratios (SMRs) were calculated by EDSS score.
Median time to death was 44.4 years. Median age at death was 76.1 years. Clinical variables associated with age at death included age at onset (hazard ratio, HR, 0.77, p<0.0001), PPMS (HR 2.38, p=0.0002), and socioeconomic status (HR 0.63, p=0.02). SMRs were no different to the general population for EDSS <7.0, but increased at higher disability levels (EDSS 7.0–7.5: 2.1, p=0.06; EDSS 8.0–8.5: 3.4, p<0.0001; EDSS 9.0–9.5: 39.5, p<0.0001).
Older age at onset, PPMS, and socioeconomic status are associated with better prognosis, and lower EDSS scores are not associated with increased mortality. These findings are of value in the contemporary analysis of therapeutic interventions on long-term prognosis.