BOSTON – Family history appeared to predict disease phenotypes for patients with psoriatic arthritis, according to the results of data presented at the 2018 Spondyloarthritis Treatment and Research Network annual meeting.
“Family history of psoriatic arthritis, compared with psoriasis, had increased risk for deformities and lower risk for plaque psoriasis,” Dilek Solmaz, MD, said.
Of the 1,393 patients analyzed, 444 had a family history of either psoriasis or psoriatic arthritis. Of those, 335 had only psoriasis in their family, while 74 patients had a family history of psoriatic arthritis.
The researchers included onset age, sex, nail involvement, enthesitis, presence of deformities, and plaque type.
In a univariate analysis, psoriasis was a risk factors for younger onset, female sex, nail disease, enthesitis, plaque type psoriasis, and not achieving minimal disease activity. Family history of psoriatic arthritis appeared to be a significant risk factor for deformations (odds ratio, 2.557) and a lower risk for plaque psoriasis (OR, 0.417).
In a multivariate analysis for family history, patients who had a family history of psoriatic arthritis had an increased risk for deformities, compared with patients with family history of psoriasis (OR, 2.143). Those patients also appeared to have a decreased risk for experiencing plaque psoriasis, compared with patients with a history psoriasis (OR, 0.324). All ORs were within the 95% confidence intervals.
“The differences between family history of psoriasis and psoriatic arthritis and their relationship between pustular and plaque phenotypes could point to different genetic backgrounds, as well as pathogenic mechanisms,” Dr. Solmaz said.