Gonzalez-GayM.A, HajeerA.H, DababnehA, MakkiR, Garcia-PorruaC, Thomson W, Ollier WER
Journal of Rheumatology. 2001;28, 1:122-125.
OBJECTIVE: To examine whether polymyalgia rheumatica (PMR) and late onset rheumatoid
arthritis have identical or similar HLA-DRB1 genetic associations. METHODS: Seventy
five PMR cases without evidence of giant cell arteritis were available for study.
One hundred seven RA cases were investigated, of which 62 had disease onset after
age 60 years. All cases were compared with 145 ethnically matched controls. All cases
and controls originated from Lugo, NW Spain. HLA-DRB1 typing was performed on DNA
samples using PCR based molecular methods. RESULTS: Early onset RA (< or =40 yrs)
was strongly associated with DRB1*04 (DRB1*0401 and *0404). In contrast late onset
RA (> or = 60 yrs) was not associated with DRB1*04 but was associated with DRB1*01.
Stratification of late onset RA cases by rheumatoid factor status revealed that DRB1*01
was only increased in seropositive RA cases. Late onset seronegative RA cases exhibited
increased frequency of DRB1*13/*14; this was also observed in PMR cases where coexistence
of GCA had been excluded. CONCLUSION: These data indicate that (1) HLA associations
with RA differ with respect to age at disease onset; and (2) seronegative late onset
RA and "isolated" PMR have a similar HLA-DRB1 association and may have an identical