Session Information
Session Type: Poster Session (Sunday)
Session Time: 9:00AM-11:00AM
Background/Purpose: In ankylosing spondylitis (AS), smokers have been found to have both higher disease activity and greater syndesmophyte progression, and a higher body mass index (BMI) has been associated with disease activity in cross sectional studies of both late and early disease. In established AS, alcohol consumption (AC) was associated with lower disease activity. However, little is known about the longitudinal effect on disease activity of such modifiable life-style factors, and very few studies have been performed in early axial spondylarthritis (axSPA). Our aim was therefore to study the relation of baseline smoking, BMI and AC with disease activity over time in early axSPA.
Methods: Data from the SPondyloArthritis Caught Early cohort, which includes patients with chronic back pain for ≥3 months, ≤2 years and onset < 45 years, were used to predict disease activity, measured as ASDAS, during the first year of follow-up. ASDAS was recorded at baseline (inclusion), after 3 and 12 months. Patients included in the analyses had a definite diagnosis of axSPA (physician’s level of confidence regarding SpA-diagnosis ≥7 on a 0-10 scale). Exposures measured at baseline were categorized as follows; BMI (normal < 25, overweight 25-29.9, obese > 30 kg/m2), smoking history (never, previous, current) and AC (none, 1-2, 3-5, ≥6 units of alcohol/week). Differences in ASDAS over 1 year by BMI category, smoking status and AC at baseline were estimated using mixed linear regression models, taking into account repeated measures of ASDAS.
Results: Of the 344 included subjects, the mean age at inclusion was 30 years and 49% were men. ASDAS decreased over the year of study with 0.58 in men and 0.46 in women. Obesity was more common in women whereas smoking and increased AC were more frequent in men (Table 1).
In age-adjusted models obesity in women (compared to normal BMI), but not in men, was associated with on average 0.58 (95% CL: 0.26, 0.90) higher ASDAS. The highest category of AC (≥6 units/week, compared to no AC) in women was associated with -0.54 (95% CL: -1.04, -0.04) lower ASDAS; and current smoking (compared to never smoking) in men with 0.32 (95% CL: 0.01, 0.63) higher ASDAS (Table 1).
In multivariate analyses including age, BMI-category, smoking history and AC the point estimates were overall similar, albeit the difference between current smokers and non-smokers in men did not reach statistical significance (Table 1).
Conclusion: Current smoking, AC and BMI, representing modifiable life style factors, were associated with disease activity over time in patients with early axSPA, with modest estimated differences and different patterns in women and men. Further analyses will explore to what extent residual confounding may explain these associations.
Table_ACR_abstract_2019_SPACE_ASDAS_final
To cite this abstract in AMA style:
Exarchou S, Turesson C, Lindström U, Ramonda R, Landewé R, Dagfinrud H, van Gaalen F, van der Heijde D, Jacobsson L. Smoking, Alcohol Intake and Body Mass Index in Prediction of Disease Activity over Time in Early Axial Spondyloarthritis – Results from the SPondyloArthritis Caught Early (SPACE) Cohort [abstract]. Arthritis Rheumatol. 2019; 71 (suppl 10). https://acrabstracts.org/abstract/smoking-alcohol-intake-and-body-mass-index-in-prediction-of-disease-activity-over-time-in-early-axial-spondyloarthritis-results-from-the-spondyloarthritis-caught-early-space-cohort/. Accessed .« Back to 2019 ACR/ARP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/smoking-alcohol-intake-and-body-mass-index-in-prediction-of-disease-activity-over-time-in-early-axial-spondyloarthritis-results-from-the-spondyloarthritis-caught-early-space-cohort/