BMI Associated With Higher Disease Activity in Women, But Not Men, With Psoriatic Arthritis

woman standing on scale, weight BMI
Feet standing on a scale with toes pointed upwards
Researchers assessed sex differences in disease activity parameters and health-related quality of life in psoriatic arthritis.

Women vs men with psoriatic arthritis (PsA) were found to have higher disease activity and were less likely to reach their treatment target, particularly if they had a higher body mass index (BMI), according to study results published in Rheumatology.

In PsA, the prevalence of the disease is similar between the sexes; however, the symptoms can vary.

This study was conducted to evaluate the sex differences in the severity of PsA and the factors related to not reaching the treatment target.

Patients from an outpatient rheumatology clinic in The Netherlands were included in the current cross-sectional study. Clinical and demographic data were used to assess the following differences between women and men: Psoriatic Arthritis Disease Activity Score (PASDAS; individual components included swollen and tender joints [SJC/TJC], enthesitis, C-reactive protein [CRP], dactylitis, physical component summary score of the short form-12 [SF12-PCS], and physician and patient global disease activity visual analog score [VAS]); skin/nail disease; mental component summary score of the short form-12 (SF12-MCS); health assessment questionnaire (HAQ); and inflammatory back pain (IBP).

A total of 855 patients with PsA were included in the study. Results indicated that mean PASDAS was significantly higher in women than men (3.5 vs 2.7, P <.001). Women vs men also had significantly worse scores for SJC, TJC, enthesitis, physician and patient global disease activity VAS, CRP, SF12-PCS, SF12-MCA, and HAQ (all P <.001). PASDAS treatment targets were more frequently not met in women vs men (odds ratio [OR], 2.03; P <.001). Factors significantly associated with not reaching the treatment target for the overall cohort included BMI, nail disease, IBP, and the number of disease-modifying antirheumatic drugs (DMARDs) used in the past or currently. Stratified for sex, BMI was associated with not reaching the treatment target in women, but not men (OR for BMI 25-30, 3.43; P <.001; OR for BMI 30-35, 2.59; P =.019; OR for BMI >35, 2.41; P =.002).

Study limitations included the cross-sectional design, lack of patients with recently diagnosed disease in the cohort, and the inability to determine the causal relationship between BMI and increased disease activity.

Researchers noted, “For [rheumatoid arthritis], there is evidence that being overweight is associated with higher disease activity in women, but not in men. To our knowledge, we are the first to show that the same holds true for PsA.” Further, “A higher BMI in women, but not men, was associated with not reaching the treatment target. This suggests that rheumatologists should pay extra attention to weight loss in the disease management of women with PsA.”


Mulder MLM, Wenink MH, Vriezekolk JE. Being overweight is associated with not reaching low disease activity in women but not men with psoriatic arthritis. Rheumatology (Oxford). Published online April 8, 2021. doi:10.1093/rheumatology/keab338