King's College London

Research portal

UK Case control study of smoking and risk of Amyotrophic Lateral Sclerosis

Research output: Contribution to journalArticlepeer-review

Sarah Catherine Martin, Ashley Richard Jones, Alfredo Iacoangeli, Ahmad Al Khleifat, Mohamad Oumar, Pamela J Shaw, Christopher Edward Dennistoun Shaw, Karen E. Morrison, Robin E Wootton, George Davey Smith, N Pearce, Ammar Al-Chalabi

Original languageEnglish
Pages (from-to)222-227
Number of pages6
JournalAmyotrophic lateral sclerosis & frontotemporal degeneration
Issue number3-4
Published17 Apr 2020


King's Authors


Introduction: Susceptibility to amyotrophic lateral sclerosis (ALS) is associated with smoking in some studies, but it is not clear which aspect of smoking behavior is related. Using detailed records of lifetime smoking we investigated the relationship between smoking and ALS in a UK population. Methods: In this retrospective case-control study, smoking status was collected using environmental questionnaires from people diagnosed with ALS between 2008 and 2013 and from age, sex and geographically matched controls. Categorical measures of smoking behavior were: smoking at the time of survey and smoking initiation; continuous measures were intensity (cigarettes per day), duration (years from starting to stopping or time of survey), cigarette pack years, and comprehensive smoking index (CSI), a measure of lifetime smoking. We used logistic regression to assess the risk of ALS with different combinations of smoking variables adjusted for age at survey, gender, level of education, smoking status and alcohol initiation, selecting the best model using the Akaike Information Criterion. Results: There were 388 records with full smoking history. The best-fitting model used CSI and smoking status at the time of survey. We found a weak association between current smoking and risk of ALS, OR 3.63 (95% CI 1.02–13.9) p value 0.05. Increase in CSI score did not increase risk of ALS: OR 0.81 (95% CI 0.58–1.11) p value 0.2.Conclusion: There is weak evidence of a positive effect of current smoking on the risk of ALS which does not show dose-dependence with higher levels of lifetime smoking and maybe a false positive result.

Download statistics

No data available

View graph of relations

© 2020 King's College London | Strand | London WC2R 2LS | England | United Kingdom | Tel +44 (0)20 7836 5454