Hand Decline Is Similar With RA, PsA, and Even Psoriasis

Loss of grip strength, fine-motor skills, and self-reported hand function appear comparable among patients with rheumatoid arthritis (RA) and patients with psoriatic arthritis (PsA), according to new study results.

“Unexpectedly, patients with psoriasis also show impaired hand function that follows a similar pattern as observed in patients with PsA,” the researchers wrote. 

The cross-sectional study assessed vigorimetric grip strength, fine‐motor skills (via the Moberg Picking‐Up Test), and self‐reported hand function (via the Michigan Hand Questionnaire) among 299 people. Of these participants, 101 had RA, 92 had PsA, 51 had psoriasis, and 55 were healthy controls.

Impaired hand function was similar among patients with RA and patients with PsA and affected muscular force, fine-motor skills, and self-perception of hand function. The decline tended to be more pronounced among women, but it affected both men and women and increased with age.

Compared with healthy control subjects, participants with psoriasis also demonstrated significant hand function impairment—a finding the researchers did not anticipate.

“Although these patients did not show any clinical signs of PsA, hand function was clearly impaired and mirrored that in patients with RA and PsA but not in healthy controls,” the researchers wrote. “This observation suggests that patients with psoriasis, per se, exhibit a functional arthritis‐like phenotype.”

“It is currently unknown whether functional changes in patients with psoriasis also indicate more pronounced progression to PsA, but this point is matter to future investigations,” they added.

—Jolynn Tumolo

Reference:

Liphardt AM, 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