Environmental risk factorsThursday, October 11, 2012, 15:30 - 17:00
Smoking and disease progression in patients with multiple sclerosis: UK cohort studyA. Manouchehrinia, C. Tench, J. Maxted, R. Bibani, J. Britton, C. Constantinescu (Nottingham, GB)
Objectives: To investigate the association between smoking and progression of disability in a large British cohort of patients with Multiple Sclerosis (MS).
Design: A cohort study of patients recorded in the Nottingham University Hospital MS clinic database. Smoking status at the onset of the disease and before diagnosis, Expanded Disability Scale Status (EDSS) and MS Severity Scores (MSSS), age, sex, type of MS, duration of immunomodulatory treatment and disease duration were obtained from medical records, and the independent effects of smoking on disease progression assessed using ordered logistic and linear regression analysis. Smoking prevalence in the cohort was compared with national UK population data.
Main Outcome Measure: EDSS score and MSSS
Results: We analysed date from 895 patients (270 male, 625 female), mean (SD) age 49(11) years with mean disease duration 17 (10) years. Approximately half of participants (49%) had Relapsing-Remitting (RR) disease type, 39% Secondary Progressive (SP), and 11% Primary Progressive (PP). Half (49%) of patients were regular smokers at the time of disease onset or at diagnosis (ever-smoker). Age- , sex- and period- standardised prevalence of ever-smoking increased relative to the UK population by 13% in females and 16% in males over the 1980 to 2010 period. Average disease progression as measured by MSSS change was greater in ever-smokers, by 0.74 (P=0.001, 95%CI: 0.40 to 1.07). The odds ratios for the likelihood of reaching EDSS score milestones 4 and 6 in ever-smokers compared to never-smokers were 2.20 (P=0.001, 95%CI: 1.58 to 3.06) and 1.63 (P=0.001, 95%CI: 1.20 to 2.20) respectively.
Conclusions: This study suggests that patients with MS are more likely to have been smokers, and that ever-smoking is associated with more rapid disease progression.
This study received no specific funding support.
Authors have nothing to disclose