Article Text

Download PDFPDF
Quantification of the influence of cigarette smoking on rheumatoid arthritis: results from a population based case-control study, using incident cases
  1. P Stolt1,2,
  2. C Bengtsson1,
  3. B Nordmark1,3,
  4. S Lindblad3,
  5. I Lundberg4,
  6. L Klareskog3,
  7. L Alfredsson1,
  8. the other members of the EIRA study group
  1. 1Institute of Environmental Medicine, Karolinska Institutet, Box 210, S-171 77 Stockholm, Sweden
  2. 2Rheumatology Clinic, Vasteras Hospital, S-721 89 Vasteras, Sweden
  3. 3Rheumatology unit, Department of Medicine, Karolinska Hospital, S-171 76 Stockholm, Sweden
  4. 4Department of Public Health Sciences, Karolinska Institutet, S-171 77 Stockholm, Sweden
  1. Correspondence to:
    Dr P Stolt, Institute of Environmental Medicine, Karolinska Institutet, Box 210, S-171 77 Stockholm, Sweden;


Objective: To quantify the influence of cigarette smoking on the risk of developing rheumatoid arthritis (RA).

Methods: 679 cases and 847 controls included during May 1996–June 2000 in a case-control study, using incident cases, comprising the population aged 18–70 years of a defined area of Sweden, were investigated. A case was defined as a person from the study base who received for the first time a diagnosis of RA using the 1987 American College of Rheumatology criteria, and controls were randomly selected from the study base. Self reported smoking habits among cases and controls, and rheumatoid factor status among cases were registered. The incidence of RA in current smokers, ex-smokers, and ever-smokers, respectively, was compared with that of never-smokers.

Results: Current smokers, ex-smokers, and ever-smokers of both sexes had an increased risk for seropositive RA (for ever-smokers the odds ratio was 1.7 (95% confidence interval (95% CI) 1.2 to 2.3) for women, and 1.9 (95% CI 1.0 to 3.5) for men), but not for seronegative RA. The increased risk was only apparent among subjects who had smoked ⩾20 years, was evident at an intensity of smoking of 6–9 cigarettes/day, and remained for up to 10–19 years after smoking cessation. The risk increased with increasing cumulative dose of smoking.

Conclusion: Smokers of both sexes have an increased risk of developing seropositive, but not seronegative, RA. The increased risk occurs after a long duration, but merely a moderate intensity, of smoking and may remain for several years after smoking cessation.

  • cigarette smoking
  • rheumatoid arthritis
  • rheumatoid factor
  • sex
  • ACR, American College of Rheumatology
  • BMI, body mass index
  • CI, confidence interval
  • EIRA, Epidemiological Investigation of RA (study)
  • OR, odds ratio
  • RA, rheumatoid arthritis
  • RF, rheumatoid factor

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • Ingeli Andréasson, Rheumatology unit at Engelbrektsgatan 34A, Gothenburg; Eva Baecklund, Akademiska Hospital, Uppsala; Helene Bolinder, Danderyds Hospital; Johan Bratt, Huddinge University Hospital; Kristina Forslind, Helsingborg Hospital; Ingiäld Hafström, Huddinge University Hospital; Kjell Huddénius, Rheumatology Clinic in Stockholm City; Shirani Jayawardena, Rheumatology unit, Bollnäs; Catarina Keller, Helsingborg Hospital; Ido Leden, Kristianstad Hospital; Göran Lindahl, Danderyds Hospital; Bengt Lindell, Kalmar Hospital; Christina Lindström, Sophiahemmet; Björn Löfström, Kullbergska Hospital; Ethel Nilsson, Vrinnevi Hospital; Anna Nordenstedt, Rheumatology Clinic in Stockholm City; Ingemar Petersson, Spenshult Hospital; Gun Sandahl, Sophiahemmet; Christoph Schaufelberger, Sahlgrenska University Hospital, Mölndal; Lars Sköldstam, Kalmar Hospital; Olle Svernell, Västevik Hospital; Berit Sverdrup, Eskilstuna Hospital; Tomas Weitoft, Gävle Hospital.