A decrease in disease activity score (DAS) level is associated with a decrease in health assessment questionnaire (HAQ) score, independent of follow-up duration, during 5 years of tightly controlled treatment: results from the BeSt study

Author(s):
Kooi, E. van der; Klarenbeek, N.B.; Guler-Yuksel, M.; Kerstens, P.J.S.M.; Lubbe, P.A.H.M. van der; Westedt, M.L.; Wolde, S. ten; Huizinga, T.W.J. (0000-0001-7033-7520); Dijkmans, B.A.C.; Allaart, C.F.
Published
2011
Publication type
Article / Letter to editor

Abstract

Objective To assess the relationship between a decrease in disease activity score (DAS) and functional ability during 5 years of DAS-steered treatment in recent-onset rheumatoid arthritis (RA) patients, taking into account absolute DAS levels and follow-up duration.

Methods Data from the BeSt study were used, in which treatment was aimed at achieving DAS <= 2.4. The longitudinal relationship between 3-monthly measured DAS and health assessment questionnaire (HAQ) score was assessed using linear mixed modelling during 5 years of treatment, with DAS and HAQ 3 months earlier, change in DAS in last 3 months (delta DAS), time (log-transformed) and their interactions as determinants.

Results Predictors for HAQ were: previous DAS, delta DAS, In time, the interaction previous DAS x delta DAS, and previous HAQ. The interaction In time x delta DAS was non-significant, indicating that the association between delta DAS and HAQ was independent of follow-up duration. A decrease from a higher DAS was associated with a smaller HAQ decrease than for a similar decrease from a lower DAS, indicating a non-linear relationship between DAS and HAQ.

Conclusion At any time during 5 years of follow-up, a decrease in DAS was associated with a better functional ability. The magnitude of HAQ improvement depends on the DAS decrease and on the absolute DAS level.

early rheumatoid-arthritis combination therapy functional-capacity controlled-trial methotrexate classification criteria strategy damage
Date issued
2011-01-31
Language
English
Is part of
Annals of the Rheumatic Diseases (2011), Vol. 70, no. 1, p. 168-171
hdl
1887/110026
doi
10.1136/ard.2010.133132