Effect of cigarette smoking and alcohol consumption on disease activity and physical functioning in ankylosing spondylitis: a cross-sectional study.

The effect of cigarette smoking and alcohol consumption on the disease activity and physical functioning in ankylosing spondylitis (AS) is currently understated. Present study aims to investigate the relationship between them. A total of 425 patients with AS were recruited in the study and their smoking and drinking habit were investigated with a semi-quantitative food frequency questionnaire. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), and Metrology Index (BASMI) were evaluated. Parameters including fingertip-to-floor distance, overall assessment of health, nocturnal pain, total back pain and morning stiffness were analyzed as well. Blood erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were determined. For 118 (27.8%) AS patients with smoking habit, the scorings of BASDAI, BASFI, BASMI and other physical parameters (including fingertip-to-floor, overall assessment of health, nocturnal pain and total back pain) were higher than those in patients without smoking. 101 (23.8%) AS patients with alcohol consumption demonstrated significantly higher scores in BASMI (P < 0.05). In hierarchical multiple regression analysis, the cigarette smoking and alcohol consumption variables contributed to the variance in BASDAI scores, adding an additional 1.6% to the overall R-square, resulting in a final R-square of 5.1%. Smoking has a negative effect on disease activity of patients with AS and the patients' physical functioning. Alcohol consumption would aggravate the overall physical functioning of AS patient. The results indicated the potential benefit of quitting smoking and drinking for AS patients.