Are Antinuclear Antibodies and Rheumatiod Factor Positivity More Prevalent in Apparently Healthy Smokers Compared to Ex-Smokers and Never Smokers?

<p><strong>Context:</strong> There is now consistent evidence from population and epidemiological studies that cigarette smoking is an independent risk factor for Rheumatoid Arthritis (RA), via Rheumatoid Factor (RF) production (Deighton, 1997; Saag, 1997; Silman, 1996; Uhlig, 1999; Wolfe, 2000). Antinuclear Antibodies (ANA) are another collection of autoantibodies that are being associated with smoking and RA initiation. To our knowledge, no studies have examined the effects of smoking on both ANA and RF simultaneously in healthy subjects.</p> <p><strong>Objectives:</strong> To determine whether cigarette smoking has an effect on ANA and RF positivity in healthy blood donors.</p> <p><strong>Design, Setting, Participants:</strong> This was a cross-sectional, observational, retrospective study. 576 consenting volunteer blood donors recruited from the local blood banks gave additional blood samples, answered the general blood bank questionnaire and our study questionnaire. Data on demographics, smoking history and selected RA risk factors were collected.</p> <p><strong>Main Outcome Measures:</strong> ANA and RF positivity.</p> <p><strong>Results:</strong>Moderate and light lifetime smoking was protective for ANA positivity relative to non-smoking and heavy smoking (O/?=2.670, 95% C7= 1.322-5.391, /?=0.006). Simple contrasts suggested this was due to moderate lifetime smoking being protective for ANA positivity compared to non-smoking (<9/?=0.337, 95% C7=0.115-0.989, p=0.048) and heavy smoking (<9/?=0.173, 95% C/=0.055-0.545,/?=0.003). No associations were found between current smoking status and ANA or RF positivity. Nor was one found with past and current second hand smoke. For never smokers there was an interaction of second hand smoke exposure with age. Those not exposed to second hand smoke showed increasing probability of ANA positivity with age. Those exposed to second hand smoke showed no such increase (0/?=0.908, 95% C7=0.828-0.996, /?=0.042). Total years smoked for exsmokers increased the likelihood of testing positive for ANA (0/?=l.O45, 95% C/+1.007- 1.084, /?=0.021). No associations were found between smoking status and ANA or RF positivity.</p> <p><strong>Conclusion:</strong> Immunological changes induced by smoking or nicotine may help explain the observed biphasic effect found with ANA positivity. For ex-smokers, smoke exposure may produce a permanent physiological change on the formation of ANA complexes that is irreversible.</p>

Name thesis:degree_name

Doctor of Public Health (DrPH)

Level thesis:degree_level

Dissertation

Year

2003

Author dc:creator

• Nyanzi, Susan

Contributors dc:contributor

• Jerry W. Lee
• Kristian Lindsted
• Edwin Krick

• Preventive Medicine
• Rheumatology
• Arthritis, Rheumatoid -- etiology; Smoking -- adverse effects; Antibodies, Antinuclear.

Statement dc:rights

• This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Language dc:language

English

Repository record dc:identifier

https://scholarsrepository.llu.edu/etd/931

OAI identifier oai:identifier

oai:scholarsrepository.llu.edu:etd-2039