Table 2

 Disease characteristics at first visit

Disease characteristics at baseline1970s (n = 98)1980s (n = 222)1990s (n = 98)p Value*
ESR, erythrocyte sedimentation rate; HAQ, Stanford Health Assessment Questionnaire25; IQR, interquartile range; VAS, Visual Analogue Scale.
Values are given in mean (SD) if not indicated otherwise. When not normally distributed, medians and IQRs of variables are reported.
*Significance of differences between decades in covariates: one-way analysis of variance of means of normally distributed continuous variables; Kruskal–Wallis test for non-normally distributed variables; χ2 test for dichotomous variables.
Education level = total number of years of school and college; disease duration = duration of disease at first visit; patient’s global assessment = patient’s self-assessed disease severity based on a Visual Analogue Scale (VAS, range 0–10), higher scores indicate more severe symptoms; pain = patients’ pain levels self-assessed by using a VAS (range 0–10)], higher scores indicate more severe pain. Tender joint count = patients’ self-assessed number of tender joints, Hart-modified Ritchie index count 41; estimated prior rate of Larsen score progression = Larsen score divided by the disease duration at baseline.33
Age (years)50 (13)54 (14)57 (15)<0.01
Education level in years, Med (IQR)12 (2)12 (2)12 (1)0.74
Duration of disease in years, Med (IQR)1.1 (1.3)1.0 (1.1)0.7 (0.9)0.01
Patient’s global assessment (VAS)4.8 (1.7)5.0 (2.5)5.4 (2.4)0.22
Pain level (0–10)4.5 (2.2)4.5 (2.6)5.7 (2.7)< 0.01
RF+ (%)8386870.67
Rheumatoid nodules (%)611100.31
ESR (mm/h), Med (IQR)36 ( 34)34 (33)36 (30)0.84
Tender joint count (0–24)12.9 (5.9)9.0 (5.4)8.5 (5.5)<0.01
Functional disability (HAQ; 0–3)1.1 (1)1.2 (0.7)1.3 (0.7)0.06
Larsen score (0–250), Med (IQR)3 (8)2 (9)1 (7)0.41
Estimated prior rate Larsen score progression, Med (IQR)2.4 (6.5)1.9 (9.5)1.7 (10.5)0.11