Clinical Consultation: Smoking and rheumatoid arthritis

Smoking and the risk of rheumatoid arthritis: Genes, gender, and the latest data How strong is the evidence that smoking is a risk factor for rheumatoid arthritis?

In epidemiologic studies, cigarette smoking is strongly associated with the development of rheumatoid arthritis (RA), in particular seropositive RA. In 1987, Vessey and colleagues¹ first reported an unexpectedly elevated risk of RA among women smokers in the Oxford Family Planning Association contraceptive study.

Since then, 11 case-control and 4 cohort studies have confirmed the increased risk of incident RA associated with cigarette smoking.^1-16 In these studies, it appears that the risk is higher in men (odds ratio [OR] range, 1.9 to 4.4 in 6 case-control studies^{2,5,6,10,12,15}) than in women (OR range, 0.6 to 2.5 in 8 case-control studies^1,3-6,8,9,12 and 3 cohort studies^11,13,16). Among RA patients with first-degree relatives who have RA, the age at onset is younger in smokers than in nonsmokers.¹⁷

Smoking intensity (number of cigarettes smoked per day) and duration are both powerful predictors of RA risk, although duration may be more important.¹¹ The risk of incident RA is elevated for current and former smokers and remains elevated for up to 20 years after smoking cessation.^13,16

Cigarette smoking primarily increases the risk of seropositive (rheumatoid factor [RF]-positive and anti-cyclic citrullinated peptide [anti-CCP] antibody-positive) RA. An interesting gene-environment interaction exists between cigarette smoking and the HLA-DRB1 shared epitope. A group of HLA-DRB1 alleles strongly associated with susceptibility to RA share a region of sequence similarity--or shared epitope--at amino acid positions 70 to 74 in the third hypervariable region of the HLA-DRB1 molecule.^6,14,18 In the Epidemiological Investigation of Rheumatoid Arthritis (EIRA) cohort study in Sweden, current smokers with 2 copies of the shared epitope had a 16-fold increased risk of RF-positive RA (95% confidence interval [CI], 7.2 to 34.2)⁶ and a 21-fold increased risk of anti-CCP antibody- positive RA (95% CI, 11.0 to 40.2).¹⁴

The EIRA group has proposed a new and elegant model for the pathogenesis of anti-CCP antibody-positive RA.¹⁴ Cigarette smoking may promote citrullination (the conversion of an arginine to a citrulline residue in certain peptides), and the generation of antibodies to citrullinated proteins (anti-CCP antibodies) may then occur preferentially in persons who have the shared epitope genotypes.^14,19

References:

REFERENCES

1. Vessey MP, Villard-Mackintosh L, Yeates D. Oral contraceptives, cigarette smoking and other factors in relation to arthritis.

Contraception.

1987;35:457-464.
2. Uhlig T, Hagen KB, Kvien TK. Current tobacco smoking, formal education, and the risk of rheumatoid arthritis.

J Rheumatol.

1999;26:47-54.
3. Voigt LF, Koepsell TD, Nelson JL, et al. Smoking, obesity, alcohol consumption, and the risk of rheumatoid arthritis.

Epidemiology.

1994;5:525-532.
4. Symmons DP, Bankhead CR, Harrison BJ, et al. Blood transfusion, smoking, and obesity as risk factors for the development of rheumatoid arthritis: results from a primary care-based incident case-control study in Norfolk, England.

Arthritis Rheum.

1997;40:1955-1961.
5. Stolt P, Bengtsson C, Nordmark B, et al. Quantification of the influence of cigarette smoking on rheumatoid arthritis: results from a population based case-control study, using incident cases.

Ann Rheum Dis.

2003; 62:835-841.
6. Padyukov L, Silva C, Stolt P, et al. A gene-environment interaction between smoking and shared epitope genes in HLA-DR provides a high risk of seropositive rheumatoid arthritis.

Arthritis Rheum.

2004;50:3085-3092.
7. Hutchinson D, Shepstone L, Moots R, et al. Heavy cigarette smoking is strongly associated with rheumatoid arthritis (RA), particularly in patients without a family history of RA.

Ann Rheum Dis.

2001;60:223-227.
8. Hernandez Avila M, Liang MH, Willett WC, et al. Reproductive factors, smoking, and the risk for rheumatoid arthritis.

Epidemiology.

1990;1:285-291.
9. Hazes JM, Dijkmans BA, Vandenbroucke JP, et al. Lifestyle and the risk of rheumatoid arthritis: cigarette smoking and alcohol consumption.

Ann Rheum Dis.

1990;49:980-982.
10. Heliovaara M, Aho K, Aromaa A, et al. Smoking and risk of rheumatoid arthritis.

J Rheumatol.

1993;20:1830-1835.
11. Karlson EW, Lee IM, Cook NR, et al. A retrospective cohort study of cigarette smoking and risk of rheumatoid arthritis in female health professionals.

Arthritis Rheum

. 1999;42:910-917.
12. Krishnan E, Sokka T, Hannonen P. Smoking-gender interaction and risk for rheumatoid arthritis.

Arthritis Res Ther.

2003;5:R158-R162.
13. Criswell LA, Merlino LA, Cerhan JR, et al. Cigarette smoking and the risk of rheumatoid arthritis among postmenopausal women: results from the Iowa Women's Health Study.

Am J Med.

2002;112:465-471.
14. Klareskog L, Stolt P, Lundberg K, et al. A new model for an etiology of rheumatoid arthritis: smoking may trigger HLA-DR (shared epitope)-restricted immune reactions to autoantigens modified by citrullination.

Arthritis Rheum.

2006;54:38-46.
15. Reckner Olsson A, Skogh T, Wingren G. Comorbidity and lifestyle, reproductive factors, and environmental exposures associated with rheumatoid arthritis.

Ann Rheum

Dis.

2001;60:934-939.
16. Costenbader KH, Feskanich D, Mandl LA, Karlson EW. Smoking intensity, duration, and cessation, and the risk of rheumatoid arthritis in women.

Am J Med.

2006; 119:503-511.
17. Hutchinson D, Lynch MP, Moots RJ, et al. The influence of current cigarette smoking on the age of onset of rheumatoid arthritis (RA) in individuals with sporadic and familial RA.

Rheumatology (Oxford)

. 2001;40:1068-1070.
18. Gregersen PK, Silver J, Winchester RJ. The shared epitope hypothesis. An approach to understanding the molecular genetics of susceptibility to rheumatoid arthritis.

Arthritis Rheum.

1987;30:1205-1213.
19. Hill JA, Southwood S, Sette A, et al. Cutting edge: the conversion of arginine to citrulline allows for a high-affinity peptide interaction with the rheumatoid arthritis-associated HLA-DRB1*0401 MHC class II molecule.

J Immunol.

2003;171:538-541.