Smoking affects the interferon beta treatment response in multiple sclerosis

Research output: Contribution to journalJournal articleResearchpeer-review

Eva R Petersen, Annette B Oturai, Nils Koch-Henriksen, Melinda Magyari, Per S Sørensen, Finn Sellebjerg, Helle B Søndergaard

OBJECTIVE: To investigate whether smoking in patients with relapsing-remitting multiple sclerosis (RRMS) treated with interferon beta (IFN-β) is associated with the relapse rate and whether there is an interaction between smoking and human leukocyte antigen (HLA)-DRB1*15:01, HLA-A*02:01, and the N-acetyltransferase-1 (NAT1) variant rs7388368A.

METHODS: DNA from 834 IFN-β-treated patients with RRMS from the Danish Multiple Sclerosis Biobank was extracted for genotyping. Information about relapses from 2 years before the start of treatment to either the end of treatment or the last follow-up visit was obtained from the Danish Multiple Sclerosis Treatment Register. Smoking information came from a comprehensive questionnaire.

RESULTS: We found that the relapse rate in patients with RRMS during IFN-β treatment was higher in smokers compared to nonsmokers, with an incidence rate ratio (IRR) of 1.20 (95% confidence interval [CI] 1.021-1.416, p = 0.027) and with an IRR increase of 27% per pack of cigarettes per day (IRR 1.27, 95% CI 1.056-1.537, p = 0.012). We found no association or interaction with HLA and the NAT1 variant.

CONCLUSION: In this observational cohort study, we found that smoking is associated with increased relapse activity in patients with RRMS treated with IFN-β, but we found no association or interaction with HLA or the NAT1 variant.

Original languageEnglish
JournalNeurology
Volume90
Issue number7
Pages (from-to)e593-e600
ISSN0028-3878
DOIs
Publication statusPublished - 2018

ID: 216507136