No abstract

This study is to our knowledge the first to demonstrate the gene expression of both ERalpha and ERbeta in human articular chondrocytes. Since there are some functional differences between the two receptors, the effects of estrogen on cartilage metabolism should be elucidated by two different receptor mechanisms.

: In a large number of subjects assessed by a single observer, this study confirms other previous reports that the relationship between acetabular dysplasia and risk of hip OA is negative.

Objective-To evaluate secular trends in the incidence and prevalence of rheumatoid arthritis (RA) in Japan. Methods-The incidence and prevalence of RA were determined in a longitudinal population based study in the Kamitonda district, Wakayama, Japan, from 1965 to 1996. Results-In the study area consisting of about 3000 inhabitants, 16 incident cases, satisfying definite RA by the Rome criteria were detected during the study period. The age and sex adjusted incidence in both men and women combined and the age adjusted incidence in women significantly decreased (p<0.025 and p<0.01, respectively). The age and sex adjusted prevalence in all inhabitants tended to decrease (p<0.1), and the age adjusted prevalence in women significantly declined (p<0.025). In men, however, neither incidence nor prevalence showed significant change. Conclusions-The decline of incidence and prevalence of female RA may be reducible to some environmental changes preferentially occurring more obviously in Japanese women than in men. Because the use of oral contraceptives has been extremely low in Japan, the decline should be explained by other factors. (Ann Rheum Dis 1999;58:751-756)

The relative importance of VDR gene polymorphism in the development of OA may vary betweenethnic groups.

Objective-In view of the possible role of oestrogens in the pathogenesis of rheumatoid arthritis (RA), this study investigated the association between oestrogen receptor (OR) gene polymorphisms and RA. Methods-Pvu II and Xba I restriction fragment length polymorphisms of the OR gene were analysed in 70 male and 240 female patients with RA, and in 300 male and 350 female controls. The absence or presence of restriction sites were represented as P, p (Pvu II ) or X, x (Xba I ). The distribution of OR genotypes was compared between the RA and control subjects by sex. RA patients were divided into subgroups according to their OR genotypes, then the age at onset, seropositivity, and rheumatoid nodule positivity were compared between the subgroups. Results-The OR genotype frequency of distribution did not have significant differences between the male RA and male controls nor between the female RA and female controls. In women with RA, there was a significant diVerence of age at onset between the subgroups (uncorrected p=0.047, corrected p=0.94). Female patients with the OR genotype PPxx (homozygote of Px) tended to have developed RA at a younger age, whereas those with PPXX and ppxx (lack of Px haplotype) developed RA at an older age. In men with RA, there was no association between the OR genotype and age at onset. In seropositivity and rheumatoid nodule positivity, there was no significant diVerence between subgroups for either sex. Conclusions-Some variants of the OR gene are related to the onset of RA in women in certain age periods, suggesting the role of the interaction between the OR gene and serum concentrations of oestrogen at the onset of the disease. (Ann Rheum Dis 1999;58:7-10) Rheumatoid arthritis (RA) is an autoimmune disease that aVects women more often than men, and the severity of their symptoms is influenced by pregnancy, delivery, and menstrual cycles.

No abstract

Objective-In view of the possible role of androgens in the pathogenesis of rheumatoid arthritis (RA), this study investigated the association between repeat lengths of CAG microsatellites of the androgen receptor (AR) gene and RA. Methods-The number of CAG repeats in exon 1 of the AR gene was determined in 90 men and 276 women with RA, as well as in 305 male and 332 female controls. Results-The male RA patients tended to have shorter repeats than the male controls (22.5 versus 23.1, p=0.07), whereas the female RA patients had similar repeats to the female controls (22.7 versus 22.9, p=0.17). Patients of both sexes were divided into younger and older age at onset groups, and compared with younger and older controls. Younger onset male RA patients had significantly shorter CAG repeat lengths than the younger male controls (21.8 versus 23.2, p=0.007) or the older onset male RA patients (21.8 versus 23.2, p=0.04). Older onset male RA and both younger and older onset female RA patients had similar CAG repeat lengths when compared with their controls. Neither seropositivity nor rheumatoid nodule positivity had a significant relation with CAG repeat lengths. Conclusion-Shorter CAG repeats of the AR gene, presenting high levels of transactivation activity, are related to younger age onset male RA, suggesting the possible role of androgens as a modulating factor.