Obesity, Nail Psoriasis May Increase Psoriatic Arthritis Risk in Children with Psoriasis

Elevated body mass index (BMI) and nail psoriasis may incur a greater risk of juvenile psoriatic arthritis in children with psoriasis, according to findings from a recent study.1

The cross-sectional study leveraged data for 80 pediatric patients seen at outpatient clinics in Egypt and described clinical risk factors potentially involved in the development of psoriatic arthritis, noting age and sex did not appear to influence this risk.1

According to the National Psoriasis Foundation, in the United States, juvenile arthritis occurs in an estimated 20-45 children per 100,000 children. Of those who develop juvenile arthritis, as many as 5% have psoriatic arthritis. Additionally, up to one-third of adults with psoriasis may develop psoriatic arthritis, but estimates of risk in children with psoriasis are limited.2

“In adults, the severity of psoriasis, smoking, obesity, hypercholesterolemia, trauma, uveitis, and depression has been identified as clinical risk factors in the development of PsA. These triggers may stimulate an inflammatory cascade, ultimately leading to arthritis, enthesitis, and dactylitis,” Dina Hamdy Mohammed Abdella, PhD, of the Rheumatology & Rehabilitation and Physical Medicine Department at Tanta University in Egypt, and colleagues wrote.1 “However, for juvenile psoriatic arthritis, little is known about its risk factors for development among children with psoriasis.”

To address this gap in research, investigators conducted a cross-sectional study of 80 children seen at 2 outpatient clinics in Egypt. They divided them into 2 groups:

• Group I included children with psoriasis without arthritis seen at the Outpatient Clinic of Dermatology and Venereology Department.
• Group II included children with juvenile psoriatic arthritis diagnosed according to ILAR criteria seen at the Outpatient Clinic of Rheumatology, Rehabilitation and Physical Medicine Department.

In total, Group I included 40 children with psoriasis without arthritis; 24 females and 16 males with a mean age of 12.1 ± 2.95 years. Group II included 40 children with juvenile psoriatic arthritis; 27 females and 13 males with a mean age of 11.0 ± 2.53 years. Investigators noted there were no significant differences between the groups regarding age, sex, or family history of psoriasis.1

Upon analysis, passive smoking was non-significantly significantly greater in Group II (37.5%) than Group I (25%; P = .228) Regarding BMI, a significant difference was observed between the 2 groups (P <.001), with a higher percentage of overweight and obesity detected in Group II (47.5% and 32.5%, respectively) than in Group I (2.5% and 15%).1

Further analysis of disease duration of psoriasis revealed a significantly greater duration in Group I compared to Group II (P <.001), but no significant difference was detected regarding PASI score (P = .392). Of note, the groups showed significant differences regarding site of psoriasis, with 65% of Group II having nail psoriasis compared to 22.5% in Group I. Additionally, Group II had a significantly higher ESR and CRP compared to Group I (P <.001).1

By binary logistic regression, overweight, obesity, and nail psoriasis were identified as predictors for developing juvenile psoriatic arthritis (P <.05 and odds ratio > 1 with 95% CI).1

“Different clinical risk factors may be involved in the development of juvenile psoriatic arthritis in children with psoriasis, including higher BMI and nail psoriasis,” investigators concluded.1

References

1. Abdella D, Abd Elghany A, Sarsik, S. et al. Factors predicting juvenile psoriatic arthritis in children with psoriasis. Egypt Rheumatol Rehabil 52, 46 (2025). https://doi.org/10.1186/s43166-025-00344-2

2. National Psoriasis Foundation. PsA in Kids and Teens. April 28, 2021. Accessed July 18, 2025. https://www.psoriasis.org/advance/psa-in-kids-and-teens/