OBJECTIVE: To compare patients with familial versus sporadic psoriatic arthritis (PsA) with respect to clinical, radiological and immunogenetic features. METHODS: All patients were identified from the University of Toronto Psoriatic Arthritis Clinic. Familial and sporadic PsA were distinguished based on the proband's self-reported history. The probands were compared at presentation to clinic with respect to: demographic information, age of onset of psoriasis and inflammatory arthritis, disease activity, disease damage, laboratory variables, functional class and HLA antigens. The two groups were compared using a univariate analysis. RESULTS: In total 407 patients were included. Thirty-six patients (8.8%) were eliminated as they reported a family history of arthritis in the absence of psoriasis. Of the remaining 371 patients, 150 patients reported a positive family of either PsA or psoriasis. 221 patients (54.2%) had no family history of psoriatic arthritis, psoriasis, or "arthritis". The familial group were younger at presentation to clinic (p = 0.003), had an earlier age of onset of psoriasis (p = 0.001) and inflammatory arthritis (p = 0.001) and were more likely to be receiving treatment (p = 0.001). The mean number of actively inflamed joints was higher in the sporadic group (p = 0.035), along with a higher frequency of rheumatoid factor positivity (p = 0.04). Only the age of onset variables and medication use retained significance after correction for multiple comparisons. CONCLUSIONS: In comparing probands with familial versus sporadic PsA, we noted a marked difference in the age of onset of psoriasis and inflammatory arthritis, along with other differences in several clinical variables. These differences may be helpful in identifying PsA patients with a stronger genetic predisposition.
OBJECTIVE: To compare patients with familial versus sporadic psoriatic arthritis (PsA) with respect to clinical, radiological and immunogenetic features. METHODS: All patients were identified from the University of Toronto Psoriatic Arthritis Clinic. Familial and sporadic PsA were distinguished based on the proband's self-reported history. The probands were compared at presentation to clinic with respect to: demographic information, age of onset of psoriasis and inflammatory arthritis, disease activity, disease damage, laboratory variables, functional class and HLA antigens. The two groups were compared using a univariate analysis. RESULTS: In total 407 patients were included. Thirty-six patients (8.8%) were eliminated as they reported a family history of arthritis in the absence of psoriasis. Of the remaining 371 patients, 150 patients reported a positive family of either PsA or psoriasis. 221 patients (54.2%) had no family history of psoriatic arthritis, psoriasis, or "arthritis". The familial group were younger at presentation to clinic (p = 0.003), had an earlier age of onset of psoriasis (p = 0.001) and inflammatory arthritis (p = 0.001) and were more likely to be receiving treatment (p = 0.001). The mean number of actively inflamed joints was higher in the sporadic group (p = 0.035), along with a higher frequency of rheumatoid factor positivity (p = 0.04). Only the age of onset variables and medication use retained significance after correction for multiple comparisons. CONCLUSIONS: In comparing probands with familial versus sporadic PsA, we noted a marked difference in the age of onset of psoriasis and inflammatory arthritis, along with other differences in several clinical variables. These differences may be helpful in identifying PsA patients with a stronger genetic predisposition.
Authors: Ari Karason; Johann E Gudjonsson; Ruchi Upmanyu; Arna A Antonsdottir; Valdimar B Hauksson; E Hjaltey Runasdottir; Hjortur H Jonsson; Daniel F Gudbjartsson; Michael L Frigge; Augustine Kong; Kari Stefansson; Helgi Valdimarsson; Jeffrey R Gulcher Journal: Am J Hum Genet Date: 2002-12-09 Impact factor: 11.025