Treat-to-target: rationale and strategies.

Treatment to a target level of a variable known to be associated with bad disease outcome is a concept that has been applied for many years in several specialties. In rheumatology this has not been the case, primarily because of the complexity of measures assessing disease activity of RA and insufficient knowledge of optimal strategies. Meanhwile, however, our insights into the devastating role of active disease have expanded. In parallel, the use of composite measures of disease activity to control patients tightly and adapt therapy accordingly has provided the evidence that treating RA to a target value of low disease activity or remission conveys significant benefit. The background of the treat-to-target concept and future aspects are discussed.