RT Journal Article SR Electronic T1 Is hormone replacement therapy protective for hand and knee osteoarthritis in women?: The Chingford study JF Annals of the Rheumatic Diseases JO Ann Rheum Dis FD BMJ Publishing Group Ltd and European League Against Rheumatism SP 432 OP 434 DO 10.1136/ard.56.7.432 VO 56 IS 7 A1 T D Spector A1 D Nandra A1 D J Hart A1 D V Doyle YR 1997 UL http://ard.bmj.com/content/56/7/432.abstract AB OBJECTIVES To explore whether hormone replacement therapy (HRT) has a protective role for osteoarthritis (OA) of the hand and knee in a cross sectional study of women in the general population.METHODS 1003 women aged 45-64 (mean age 54.2) from the Chingford Study were asked details of HRT use. Standard anteroposterior radiographs of hands, knees were taken and scored according to the methods of Kellgren and Lawrence (grade 2+ positive for OA), and using individual features of osteophytes and joint space narrowing. Analysis compared ever use (> 12 months) versus never use, and current use (> 12 months) versus never use. Only 606 definitely postmenopausal women were included in the analysis. Odds ratios and 95% confidence intervals were calculated using logistic regression for risk of user versus non-user at each site, adjusted for age, height and weight, menopausal age and for bone mineral density of the femoral neck.RESULTS For current users (n=72) there was a significant protective effect of HRT for knee OA (defined by Kellgren and Lawrence grade or osteophytes 0.31 (95% CI 0.11, 0.93), and a similar but not significant effect for moderate joint space narrowing of the knee, 0.41 (95% CI 0.05, 3.15) and for distal interphalangeal OA 0.48 (95% CI 0.17, 1.42). No clear effect was seen for the carpometacarpal joint, CMC OA 0.94 (95% CI 0.44, 2.03). When analysing ever users (n=129) the protective effect was reduced. For ex-users of >12 months (mean duration 40.7 months), there was no overall protective effect of HRT for OA. Additional adjustment for hysterectomy, physical activity, social class, and smoking made little difference to the results.CONCLUSIONS These data show an inverse association of current HRT use and radiological OA of the knee suggestive of a protective effect. The effect was weaker in the hand joints. The mechanism of the protection is unclear but has important implications for aetiopathogenesis.