Psoriatic arthritis (PsA) and rheumatoid arthritis (RA) have a similar effect on hand function, including muscular force, fine-motor skills, and self-perception, according to study results published in ACR Open Rheumatology. However, hand function was found to be impaired in patients with psoriasis, suggesting a functional arthritis-like phenotype.
Previous studies have shown that both RA and PsA may have a significant effect on the musculoskeletal system. While studies have explored the effect of RA on hand function, limited data are available on the effect of PsA on hand function.
The objective of the current cross-sectional study was to determine the effect on objective and subjective parameters of hand function, including assessment of muscular force, fine-motor skills, and self-perception, in patients with PsA, psoriasis, and RA.
Assessment of hand function was completed using a dynamometer to determine grip strength, the Moberg Picking-Up Test (MPUT) to assess fine-motor skills, and the Michigan Hand Questionnaire (MHQ) for self-reported hand function.
The study sample included 299 participants, including 101 with RA, 92 with PsA, 51 with psoriasis, and 55 healthy control participants.
Study results showed that grip strength was reduced among women with PsA, RA, and psoriasis, whereas, there was a modest disease-related reduction of grip strength among men, a finding that was only significant among those who were older. Other than age, hand function was also significantly affected by disease status, sex, and hand dominance.
Compared with healthy control participants, older patients with RA, PsA, and psoriasis were found to have significantly higher MPUT times, suggesting worse fine-motor skills. Regression analysis suggested a significant effect of age and disease status on fine-motor skills.
Self-reported hand function revealed a significant effect of age, disease status, and hand dominance on MHQ score. The effect of disease on the MHQ score increased with age and was more pronounced among women.
“Both PsA and RA led to significantly enhanced age-related loss of grip strength, fine-motor skills, and self-reported hand function in patients with PsA and RA compared with healthy control [participants],” the researchers concluded.
Disclosure: This clinical trial was supported by Novartis Germany GmBH. Please see the original reference for a full list of authors’ disclosures.
Liphardt A-M, Manger E, Liehr S, et al. Similar impact of psoriatic arthritis and rheumatoid arthritis on objective and subjective parameters of hand function. ACR Open Rheumatol. Published online November 25, 2020. doi:10.1002/acr2.11196