Table 1.
Baseline characteristics of patients with early arthritis.
Figure 1.
Variability of VIP levels in healthy controls (n = 100) and patients with early arthritis (Rheumatoid arthritis n = 69, Undifferentiated arthritis n = 22).
Data are presented as the interquartile range (p75 upper edge of the box, p25 lower edge, p50 midline), p90 (line above the box), and p10 (line below the box) of the serum VIP levels. Dots represent outliers. Dashed lines show the 25th percentile of the healthy donor group.
Figure 2.
VIP serum levels correlate inversely with disease activity in patients with early arthritis.
A) Progress of disease activity estimated by DAS28 at follow-up visits. B) Serum levels of VIP during the follow-up period. C) Serum VIP levels considering disease activity level. Data are presented as the interquartile range (p75 upper edge of the box, p25 lower edge, p50 midline), p90 (line above the box), and p10 (line below the box) of the serum VIP levels. Dots represent outliers. Statistical significance was established using the Kruskal-Wallis test in panels A and B. In panel C the significance level is that obtained in the multivariable analysis displayed in Table 2, model 2.
Table 2.
Variables associated with VIP serum levels during follow-up of patients with early arthritis.
Figure 3.
Serum VIP level as a prognostic marker.
A) VIP levels at baseline according to the degree of disease activity after two years of follow-up. B) Intensity of treatment in two subpopulations of early arthritis patients clustered according to serum VIP level. Cumulative DMARD treatment during the follow-up period was estimated using the intensity of DMARD treatment (IDT) variable (see Methods). C) Disease activity estimated by DAS28 after two years of follow-up in a population of patients with early arthritis according to VIP levels and the presence of anti-citrullinated peptide antibody (ACPA+). D) Intensity of DMARD treatment in different subpopulations clustered by serum VIP levels and the presence of ACPA. Data are presented as the interquartile range (p75 upper edge of the box, p25 lower edge, p50 midline), p90 (line above the box), and p10 (line below the box). Dots represent outliers. Statistical significance was established using the Kruskal-Wallis test in panels A, C and D or Mann-Whitney test in panel B.
Table 3.
Effect of low baseline VIP levels in serum on disease activity after a two-year follow-up.