Lower levels of physical activity, younger age, and not using biologics were associated with less enthesis inflammation among patients with psoriatic arthritis (PsA), according to study data published in the Journal of Rheumatology.
Investigators recruited consecutive patients with PsA from 3 outpatient clinics in The Netherlands for this cross-sectional study. In a structured interview, patients answered questions regarding PsA and their physical activity levels, including any disease-related avoidance of physical activity. Clinical PsA characteristics were determined with a physical examination.
Ultrasound (US) examinations were also performed, and inflammatory and structural enthesis changes were scored with the modified Madrid Sonographic Enthesitis Index (MASEI). Linear regression was performed to identify associations between US scores and clinical characteristics. US scores of healthy volunteers and patients with PsA were compared using Wilcoxon rank-sum tests.
The final cohort comprised 84 patients with PsA, among whom 45 (54%) were men. The mean age was 55±11 (range, 26-76) years, and mean body mass index was 27±5 kg/m2. Median disease duration among patients was 8 years. Forty patients (48%) reported that they regularly exercised, among whom 17 (43%) reported avoiding activities.
Among patients not exercising regularly, avoidance of physical activity was reported by 28 (64%). Older age (P =.05) and current use of biologics (P =.029) were each associated with higher inflammatory-modified MASEI score. Patients who reported avoiding activities had significantly lower inflammatory-modified MASEI scores compared with patients who did not (P =.017).
Total US scores of patients aged 35 to 60 years (n=50) were compared with those of 25 healthy volunteers in the same age range. The modified MASEI scores were 11 (interquartile range, 6.5-15) in patients and 7.5 (interquartile range, 5-9) in healthy volunteers (P =.01).
Inflammatory-modified MASEI scores were similar among patients and volunteers, whereas structural-modified MASEI scores were much higher among patients when compared with volunteers (median, 6 vs 2; P =.01).
Avoidance of physical activity, younger age, and not using biologic disease-modifying drugs were associated with less inflammation of the entheses. Prospective longitudinal research is necessary to explain these associations, particularly the relationship between physical exercise and inflammation.
Wervers K, Herrings I, Luime JJ, et al. Association of physical activity and medication with enthesitis on ultrasound in psoriatic arthritis [published online May 1, 2019]. J Rheumatol. doi:10.3899/jrheum.180782