title: Smoking and alcohol use are associated with structural and inflammatory hand osteoarthritis features.
abstract: OBJECTIVE
  To explore whether smoking and alcohol use are associated with hand osteoarthritis (OA) features in two different OA cohorts.
  
  
  METHODS
  We studied 530 people with radiographic hand OA from the Musculoskeletal pain in Ullensaker STudy (MUST) and 187 people from the Oslo hand OA cohort [mean (sd) age 65 (8.0) and 62 (5.7) years, 71% and 91% women, respectively]. Smoking, alcohol use and hand pain were self-reported. Participants underwent conventional hand radiographs and ultrasound examination of 30 hand joints. The Kellgren-Lawrence sum score for radiographic OA severity (0-120 scale) and the proportion of participants having at least one joint with grey-scale synovitis (grade ≥1) were calculated. We studied whether smoking and alcohol use were cross-sectionally associated with radiographic OA, synovitis, and pain using adjusted linear and logistic regression analyses.
  
  
  RESULTS
  Smoking was associated with less radiographic OA in both cohorts [β = -4.71, 95% confidence interval (CI) -8.36 to -1.06 for current smoking in MUST and β = -0.15, 95% CI -0.29 to -0.02 for smoking pack-years in the Oslo hand OA cohort]. Stratified analyses indicated that the association was present in men only. Being a monthly drinker (examined in MUST only) was significantly associated with present synovitis compared to never drinkers (odds ratio = 2.35, 95% CI 1.27 to 4.34) (no gender differences). Neither smoking nor alcohol was associated with hand pain.
  
  
  CONCLUSIONS
  Smoking was associated with less radiographic hand OA whereas alcohol consumption was associated with present joint inflammation in hand OA. Future longitudinal studies are needed to explore the causal associations and explanatory mechanisms behind gender differences.
authors.affiliation: a National Advisory Unit on Rehabilitation in Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.|b Department of Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.
authors.forename: K
authors.initials: K
authors.lastname: Magnusson
authors.affiliation: b Department of Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.
authors.forename: A
authors.initials: A
authors.lastname: Mathiessen
authors.affiliation: b Department of Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.
authors.forename: H B
authors.initials: HB
authors.lastname: Hammer
authors.affiliation: b Department of Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.
authors.forename: T K
authors.initials: TK
authors.lastname: Kvien
authors.affiliation: b Department of Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.
authors.forename: B
authors.initials: B
authors.lastname: Slatkowsky-Christensen
authors.affiliation: c Department of General Practice, Institute of Health and Society , University of Oslo , Oslo , Norway.
authors.forename: B
authors.initials: B
authors.lastname: Natvig
authors.affiliation: a National Advisory Unit on Rehabilitation in Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.|b Department of Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.
authors.forename: K B
authors.initials: KB
authors.lastname: Hagen
authors.affiliation: a National Advisory Unit on Rehabilitation in Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.|b Department of Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.
authors.forename: N
authors.initials: N
authors.lastname: Østerås
authors.affiliation: b Department of Rheumatology , Diakonhjemmet Hospital , Oslo , Norway.
authors.forename: I K
authors.initials: IK
authors.lastname: Haugen
mesh_terms: D000368:Aged; D000428:Alcohol Drinking / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D050823:Hand Joints / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D059352:Musculoskeletal Pain / Q000175:diagnosis / Q000209:etiology; D009664:Norway / Q000453:epidemiology; D010003:Osteoarthritis / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D011859:Radiography / Q000379:methods; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology / Q000503:physiopathology; D013223:Statistics as Topic; D013585:Synovitis / Q000175:diagnosis / Q000209:etiology; D014463:Ultrasonography / Q000379:methods