AB0231 Health assessment questionnaire disability index score less than 0.5 is no longer target for remission in elderly rheumatoid arthritis patient, but it is independent from comorbidities
Authors: I. Yoshii, T. Chijiwa
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> It is well known fact that ageing makes deep influence on Health Assessment Questionnaire (HAQ-DI) score in normalised population. We have suggested that it is also available in rheumatoid arthritis (RA) patient.<sup>1</sup> However, the effect of ageing on the HAQ score is thought to be due to comorbidities. <h3>Objectives</h3> The aim of this study is to investigate the impact of ageing on the HAQ score statistically and to evaluate the correlation between the HAQ score and age. <h3>Methods</h3> We have been treated 516 RA patient for more than 3 years. Patient's Age, HAQ-DI score, 28-joints disease activity score with C-reactive protein (DAS28), Sharp/van der Heijde Score (SvdHS), pain score measured with visual analogue score (PS) were monitored at every another year since first consult (BL). Relationship between HAQ-DI and the other parameters including number of comorbidities (Com) at BL and last observational year period (FU), and their changes from BL to FU were evaluated statistically with multivariate linear regression analysis (MLR). After correction that aimed to minimise effects on the HAQ score of other parameters but age, relationship between the HAQ score and age was also evaluated with MLR. Relationship between age and Com was also evaluated with MLR statistically. Statistical significant level was set within 5%. <h3>Results</h3> After exclusion of cases that lacked data, 441 patients have been analysed for this study. Their average ages at onset, BL, and FU were 60.4, 65.1, and 70.9 years, respectively, and average follow-up term was 5.76 years. Woman's ratio was 75.6%, and their anti-citrullinated cyclic peptide antibodies positive ratio was 77.2%. At BL, correlation coefficient of the equation (the R-value) in MLR was 0.6251. Factors that demonstrated significant correlation with the HAQ score were PS, age, and DAS28, and their correlation coefficients (CC) were 0.00004174, 0.01943, and 0.02941, respectively. At FU, the R-value of the equation in MLR was 0.6309. Factors that demonstrated significant correlation with the HAQ score were age, Com, PS, and SvdHS, and their CCs were 0.00007042, 0.0004365, and 0.002886, 0.02354, respectively. The R-value of the change of the HAQ score correlation equation demonstrated 0.4755. Factors that demonstrated significant correlation with change of the HAQ score were changes of DAS28-CRP, PS, age, and Com, and their CC s were 0.002703, 0.003750, 0.003480, and 0.009886. Correlation procedure needed elimination of the case whose average DAS28 exceeded 2.6, SvdHS exceeded 100, and PS exceeded 20 mm. After correction, patients have been limited to 158. However, age demonstrated significant correlation with the HAQ score, and its CC was 0.00004439, and the constant of age was 0.01132. After correction, Com demonstrated no significant correlation with the HAQ score. Com demonstrated significant correlation with age with 0.01253 for CC. However, the R-value of the equation was 0.1982. <h3>Conclusions</h3> These results suggested that age have deep influence on the HAQ score. Com also affects on the HAQ score, however, Com and ageing is independent factor for each other. Therefore effect of ageing on the HAQ score is concluded independent. The HAQ score increases its standard value for approximately 0.01 as age increase one. <h3>Reference</h3> [1] Yoshii I, Chijiwa T. Arthritis Rheumatol. 2015;67(suppl 10). <h3>Disclosure of Interest</h3> None declared