Obesity and Pediatric Psoriatic Arthritis.

Objective: Studies in adults have shown a significant association between obesity and psoriatic arthritis, however the association of obesity with pediatric psoriatic arthritis is unknown. We aimed to evaluate obesity in pediatric psoriatic arthritis.

Methods: We conducted a cross-sectional study of children with psoriasis and psoriatic arthritis evaluated at a single center between 6/2010 and 9/2014. Two healthy reference populations were utilized: 1) local reference population from the surrounding community and 2) a national reference population derived from NHANES. Age and sex-specific z-scores for weight, height, and body mass index (BMI) were calculated. Differences in clinical and demographic characteristics between groups were assessed.

Results: During the study period, 48 children with psoriatic arthritis and 231 patients with psoriasis were evaluated. Three (6.2%) and 5 (10.4%) of the children with psoriatic arthritis were overweight or obese, respectively. In comparison to the reference healthy groups and psoriasis patients, the mean BMI z-score of children with psoriatic arthritis was not statistically different. However, patients with psoriasis were more likely to be obese than the community reference population (p-value <0.001).

Conclusions: Children with psoriasis were more obese than the healthy reference population, however there was no statistically significant difference in obesity between children with psoriatic arthritis and psoriasis or psoriatic arthritis and the reference population. This lack of association may be reflective of true differences in pediatric and adult-onset disease and warrants further investigation.