Effect of Smoking on Disease Activity and Functional Impairment in a Sample of Iraqi Patients with Ankylosing Spondylitis

Background:The etiology of AS is unknown, but a combination of genetic and non- genetic risk factors works in concert to produce clinical disease. Smoking has a negative impact on disease activity and functional ability in AS with more severe radiographic damage. The aim of this study is to assess the effect of smoking on AS disease indices (activity, and functional impairment).

Patients and Method: A cross sectional study was conducted on 150 AS patients. Information concerning smoking, demographic characteristics & clinical criteria data were gathered consisted of age, gender, BMI, duration of disease,Ankylosing Spondylitis Disease Activity Score (ASDAS-ESR), Bath ankylosing spondylitis disease activity index (BASDAI),Bath Ankylosing Spondylitis Functional Index (BASFI). All cases were investigated for HLA-B27 and ESR.

Results:A total of 150 patients with AS were involved in this research. The non-smokers constituted 52% of cases. Ex-smokers formed 14.7% of patients. Low grade smokers (<15 pack-year) formed 18% of patients and high grade smoker (15+ pack-year) formed 15.3% of patients. There is a positive relation and statistically significant moderately strong to strong positive linear correlation between AS disease activity, functional impairment. The mean ASDAS, BASDAI and BASFI was the lowest in non-smokers and elevate with increment in the number of cigarette smoking.

Conclusion:AS smoker cases had elevated disease activity & functional impairment.