To investigate the curative effect of rheumatoid arthritis (RA) complicated with type 2 diabetes mellitus (T2DM).

A retrospective analysis was performed on RA patients admitted to our hospital from January 2016 to December 2019. According to whether they had T2DM or not, the patients were divided into a T2DM group or non-T2DM group. General information, treatment drugs, disease activity index, and therapeutic response rate were collected. Mann-Whitney U test or non-parametric rank sum test was used for comparison of age, course of disease, body mass index (BMI), fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), rheumatoid factor, anti-cyclic citrulline peptide (CCP) antibody, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), disease activity scoring system (DAS28) score, and pain visual analogue scale (VAS) score between groups, chi-square test was used for comparison of categorical data, and Pearson analysis was used for detecting the correlation between FBG and DAS28 score.

Compared with patients without T2DM, patients with T2DM had higher age [(61.09±8.03) years vs (54.01±12.32) years], BMI [(24.20±3.96) kg/m² vs (22.95±3.66) kg/m²], FBG [(8.08±2.39) mmol/L vs (5.18±0.85) mmol/L], HbA1c [(7.51±1.45)% vs (5.41±0.55)%], ESR [(74.43±35.94) mm/h vs (62.38±32.05) mm/h], DAS28 score [(6.07±1.41) vs (5.49±1.87)], and VAS score [(5.28±1.36) vs (4.50±1.48)], and the differences were statistically significant (Z=-3.794, -2.04, -8.8593, -8.936, -2.054, -3.359, and -3.142; P<0.001, =0.041, <0.001, <0.001, =0.040, =0.001, and =0.002, respectively), while there were no statistically significant differences in gender, course of disease , RF, anti-CCP antibody, or RP (P>0.05). In terms of the treatment drugs, the rate of MTX use was significantly lower (44.68% vs 62.90%, χ²=5.159, P=0.023) and that of Tripterygium polyglycoside was significantly higher (80.85% vs 47.85%, χ²=16.479, P<0.001) in the T2DM group. There were no statistically significant differences in the use of nonsteroidal anti-inflammatory drugs, leflunomide, hydroxychloroquine sulfate, iguratimod, biological preparation, or combination medication between the two groups (P>0.05). The levels of ESR, CRP, DAS28, VAS score, and disease grade decreased significantly in both groups compared with the baseline values (P<0.01), while disease activity index of patients in the T2DM group was higher than that before treatment. In terms of blood glucose control, FBP in the T2DM group was significantly lower than the baseline value [(6.26±1.00) mmol/L vs (8.08±2.39) mmol/L, Z=-4.816, P<0.001], and the blood glucose compliance rate was significantly increased (42.55% vs 12.77%, χ²=10.421, P<0.001). The rate of good response to treatment and the overall response rate did not differ significantly between the two groups (P>0.05). Correlation analysis showed that there was a correlation between DAS28 level and fasting glucose in the T2DM group before and after treatment (r=0.305 and 0.368; P=0.037 and 0.011, respectively).

Patients with RA complicated with T2DM have higher disease activity. The combination of T2DM does not affect the therapeutic efficacy in RA patients. Remission in RA patients is helpful to improve the glycemic compliance rate of T2DM.