The predictive value of 25-(OH)D in early rheumatoid arthritis and its correlation analysis with disease activity and immune function indicators

Objective To investigate the predictive value of 25-hydroxyvitamin D[25-(OH)D] in early rheumatoid arthritis(RA) and its correlation with disease activity and immune function indicators. Methods A total of 100 patients with early RA who came to Jinhua Municipal Central Hospital from March 2016 to May 2018 were selected as research objects, and 100 healthy patients were selected as control group. The predictive value of 25-(OH)D for early RA was evaluated using the area(AUC) under the receiver operator characteristics curve(ROC). Patients with RA were divided into the following groups according to the level of 25-(OH)D:50 cases in the deficient group, 30 cases in the unsufficient group, and 20 cases in the normal group. Clinical indicators[joint tenderness number, joint swelling number, C-reactive protein(CRP), erythrocyte sedimentation rate(ESR), visual analogue score(VAS)] were compared between each groups. Spearman correlation analysis was used to analyze the correlation between 25-(OH)D and disease activity and immune function indicators. Results The AUC value predicted by 25-(OH)D for early RA was 0.904. There were statistically significant differences in the number of joint tenderness number, joint swelling number, ESR and VAS in the three groups(all P<0.05). The number of joint tenderness number, ESR and VAS in normal group were significantly lower than those in deficient group and unsufficient group(all P<0.05). The number of joint swelling and CRP in normal group were obviously lower than those in the deficient group(P<0.05). The VAS in the unsufficient group was significantly lower than that in the deficient group(P<0.05). The level of 25-(OH)D in early RA patients was negatively correlated with disease activity score-28(DAS28 score). The 25-(OH)D in early RA patients was positively correlated with regulatory T cells(P<0.05), but not correlated with immune function indicators(P>0.05). Conclusion 25-(OH)D has a high predictive value for early RA, which may play an important role in assessing the pathogenesis of RA.