Rising overweight and obesity in Swiss psoriatic arthritis patients, 2007-2022: a nationwide registry-population...

To compare overweight and obesity prevalence in Swiss patients with psoriatic arthritis (PsA) against the general Swiss population from 2007-2022, evaluate temporal trends, and assess socioeconomic correlates (age, sex, education).

We performed a repeated cross-sectional analysis of adults with PsA in the Swiss Clinical Quality Management in Rheumatic Diseases (SCQM) registry who had BMI recorded in 2007, 2012, 2017, or 2022 (patients could contribute to more than one index year). Age-, sex-, and education-stratified BMI distributions were compared with Swiss Health Survey data using χ² goodness-of-fit tests. Within PsA, clinical and socioeconomic variables were compared across BMI categories using Fisher's exact or Kruskal-Wallis tests; pairwise changes over time were assessed with one-sided Wilcoxon rank-sum tests.

Among 1,150 PsA patients in 2022, 37.6% were overweight and 28.2% obese, versus 30.9% and 12.1% in the Swiss population. In cross-sectional comparisons, obesity was associated with more frequent elevated C-reactive protein (55.8% vs. 37.0%), higher patient global assessment (mean [SD] 3.2 [2.4] vs. 2.8 [2.2]) and physician global assessment (2.5 [2.0] vs. 2.1 [1.8]), and lower EQ-5D-3L health state (0.7 [0.2] vs. 0.8 [0.2]). Obesity prevalence rose from 19.4% in 2007 to 28.2% in 2022, a trend driven by men. Obesity prevalence varied across educational strata but did not follow a monotonic social gradient; within each stratum obesity was markedly more common in PsA than in the Swiss general population.

Overweight and obesity affect nearly two-thirds of Swiss PsA patients and have increased since 2007. Cross-sectional associations between obesity, higher inflammatory burden and poorer patient-reported health state, together with the widening gap versus the general population, support integrating structured, multidisciplinary weight-management programmes into PsA treat-to-target care, particularly for men.