Incidence of total hip and total knee replacements from the prospective epidemiologic risk factor study: considerations for event driven clinical trial design.

The women with a TJR diagnosis before or after baseline were on average 1 year older (p < 0.001) and heavier (p < 0.001), compared to women with no TJR. The 3-, 6- and 12-year cumulative incidences were 1.1, 2.4 and 6.0% for TKR, and 2.1, 4.4 and 9.3% for THR. For those with an OA diagnosis at baseline the respective incidences were 2.7, 5.6 and 11.7% and 3.9, 7.2 and 13.6% CONCLUSIONS: Within 3, 6 or 12 years TJR incidences were double for women with an OA diagnosis compared to the all-comer population. TJRs are frequent amongst elderly women with OA and it is, therefore, feasible to conduct event-driven clinical trials where TJR is the endpoint demonstrating clinical benefit of a novel disease-modifying OA drug (DMOAD).