title: Lifetime occupation, education, smoking, and risk of ALS.
abstract: OBJECTIVE
  To investigate the association between cigarette smoking, level of education, occupation, and the occurrence of sporadic amyotrophic lateral sclerosis (ALS).
  
  
  METHODS
  A total of 364 patients and 392 controls completed a questionnaire covering smoking habits, level of education, and occupational history. Main occupations were coded according to the International Standard Classification of Occupations and compared between patients and controls.
  
  
  RESULTS
  The univariate analysis showed an increased risk of developing ALS among current cigarette smokers (OR = 1.7; 95% CI = 1.1 to 2.6; p = 0.01), those with a low level of education (elementary school) (OR = 2.2; 95% CI = 1.2 to 3.8; p < 0.01), and among women whose main occupation was classified as crafts and related trades workers (OR = 8.4; 95% CI = 1.0 to 70.1; p = 0.05). Multivariate analysis (with covariates age, smoking, education, and occupation) showed an increased risk for current smokers of cigarettes (OR = 1.6; 95% CI = 1.0 to 2.5; p = 0.04).
  
  
  CONCLUSIONS
  Occupation, education, and cigarette smoking are risk factors for amyotrophic lateral sclerosis, but only smoking appeared independently associated.
authors.affiliation: Department of Neurology, G03.228, University Medical Center Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands.
authors.forename: N A
authors.initials: NA
authors.lastname: Sutedja
authors.forename: J H
authors.initials: JH
authors.lastname: Veldink
authors.forename: K
authors.initials: K
authors.lastname: Fischer
authors.forename: H
authors.initials: H
authors.lastname: Kromhout
authors.forename: J H J
authors.initials: JH
authors.lastname: Wokke
authors.forename: M H B
authors.initials: MH
authors.lastname: Huisman
authors.forename: D J J
authors.initials: DJ
authors.lastname: Heederik
authors.forename: L H
authors.initials: LH
authors.lastname: Van den Berg
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000453:epidemiology*; D016022:Case-Control Studies; D004522:Educational Status; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D016273:Occupational Exposure / Q000706:statistics & numerical data*; D009790:Occupations / Q000706:statistics & numerical data*; D012307:Risk Factors; D017678:Sex Distribution; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology*; D011795:Surveys and Questionnaires