Objective:To observe the efficacy and safety of Tofacitinib in treating elderly rheumatoid arthritis(RA), in order to provide clinical evidence.Methods:In the randomized control trial, a total of 90 elderly RA patients admitted to the Department of Rheumatology of the First Affiliated Hospital of Soochow University from January 2019 to January 2021 were selected and divided into Methotrexate group(MTX group, MTX 10mg, qw, n=45)and Tofacitinib group(TOF group, oral 5mg, bid, n=45). The efficacy and safety of the two groups were evaluated at week 12.The primary endpoint was the proportion of patients meeting the American College of Rheumatology 50%(ACR50)improvement response criteria at week 12.Secondary endpoints included ACR20/70 improvement response, proportion of patients who met treat-to-target(T2T)criteria, including Disease Activity Score in 28 joints using erythrocyte sedimentation rate(DAS28-ESR), Disease Activity Score in 28 joints using C-reactive protein level(DAS28-CRP), clinical disease activity index(CDAI), and simplified disease activity index(SDAI), and patient-reported outcomes(PROs)which included changes compared to baseline in pain visual analog scale(VAS)and Health Assessment Questionnaire Disability Index(HAQ-DI)score, at week 12.Safety outcomes including drug-related adverse events, serious adverse events, dropping out due to adverse events, and deaths were assessed throughout.Results:Five patients in each group withdrew from the trial due to adverse events, and the number of patients who finally completed the observation was 40 in each group.At week 12, the ACR50 response rate was higher in TOF group than in MTX group[35%(14/40) vs.12.5%(5/40), χ2=5.591, P=0.018)], achieving the primary endpoint.When comparing TOF vs.MTX group, the ACR20 response rate[55%(22/40) vs.25%(10/40), χ2=7.500, P=0.006]and ACR70 response rate[25%(10/40) vs.7.5%(3/40), χ2=4.501, P=0.034], and proportions of indexes of disease remission including DAS28-ESR<2.6[25%(11/40) vs.7.5%(3/40), χ2=4.501, P=0.034], or DAS28-CRP<2.6[27.5%(11/40) vs.7.5%(3/40), χ2=5.541, P=0.019], or CDAI≤2.8[30%(12/40) vs.10%(4/40), χ2=5.000, P=0.025], or SDAI≤3.3[27.5%(11/40) vs.7.5%(3/40), χ2=5.541, P=0.019], and the proportions of patients with low disease activity including DAS28-ESR≤3.2[32.5%(14/40) vs.12.5%(5/40), χ2=5.591, P=0.018], or DAS28-CRP≤3.2[32.5%(14/40) vs.12.5%(5/40), χ2=5.591, P=0.018], or CDAI≤10[37.5%(15/40) vs.17.5%(7/40), χ2=4.013, P=0.045], or SDAI≤11[37.5%(15/40) vs.15%(6/40), χ2=5.230, P=0.022], as well as changes compared to baseline data in pain VAS[(26.51±8.32)scores vs.(14.16±4.39)scores, t=8.371, P<0.001]and in HAQ-DI score(0.65±0.24 vs.0.32±0.06, t=9.387, P<0.001)were all better in the TOF group than in the MTX group at week 12.During the 12-week observation period, the number of patients with infection and hyperlipidemia was higher in TOF group than in MTX group, while the number of patients with abnormal blood cell count and liver function was lower than that in MTX group, but the differences were not statistically significant(all P<0.05). Conclusions:Tofacitinib has good efficacy and safety in the elderly RA.In patients over 70 years of age who are at high risk of infection, tofacitinib should be used with caution.

BACKGROUND:The incidence of osteoporosis significantly increases in the patients with rheumatoid arthritis,and it remains unclear whether the presence of a large number of immune complexes in serum promotes the onset and development of osteoporosis. OBJECTIVE:To investigate the correlation between serum immune complexes and osteoporosis in patients with rheumatoid arthritis. METHODS:(1)Clinical trial:Serum and clinical data of 50 healthy controls and 50 patients with untreated rheumatoid arthritis were collected and retrospectively analyzed.Total immune complex level in serum was compared between two groups.Correlation of serum total immune complexes with bone mineral density,bone turnover markers and other clinical indicators in patients with rheumatoid arthritis was analyzed.(2)Cell experiment:Peripheral blood mononuclear cells from healthy volunteers were isolated and cultured,and divided into four groups:rheumatoid arthritis group was added with total immune complex suspension from rheumatoid arthritis patients;normal control group was added with total immune complex suspension from healthy medical checkups;positive control group was added with α-MEM medium containing macrophage colony-stimulating factor and receptor activator of nuclear factor-kappa B ligand,and negative control group was added with α-MEM medium.Tartrate-resistant acid phosphatase staining was performed to observe the formation of osteoclasts after 7 days of treatment, RESULTS AND CONCLUSION:(1)Clinical trial:The total immune complex and serum alkaline phosphatase levels in patients with rheumatoid arthritis were significantly higher than those in health controls(P＜0.01,P＜0.05).Pearson correlation analysis showed that serum total immune complex level was positively correlated with erythrocyte sedimentation rate(r=0.330,P=0.019),serum alkaline phosphatase(r=0.545,P=0.001),anti-cyclic citrullinate peptide(r=0.377,P=0.007)and c-terminal telopeptide of type Ⅰ collagen(r=0.738,P=0.001),and negatively correlated with lumbar bone mineral density(r=-0.595,P=0.001)in patients with rheumatoid arthritis.Binary Logistic regression analysis showed that age[odds ratio(OR)=1.086,95%confidence interval(CI)(1.022,1.154),P=0.008],anti-cyclic citrullinate peptide[OR=1.002,95%CI(0.999,1.005),P=0.035],c-terminal telopeptide of type Ⅰ collagen[OR=0.141,95%CI(0.015,8.900),P=0.008]and serum total immune complexes[OR=2.895,95%CI(1.228,6.827),P=0.001]were the influencing factors for abnormal bone mass(reduced bone mass or osteoporosis)in patients with rheumatoid arthritis.(2)Cell experiment:Tartrate-resistant acid phosphatase positive osteoclasts were observed in the positive control group,normal control group and rheumatoid arthritis group,and there were more osteoclasts in the rheumatoid arthritis group than in the normal control group(P＜0.01).To conclude,serum total immune complexes can be used as a potential serologic predictor of rheumatoid arthritis complicated with osteoporosis,and removing immune complexes in serum or interfering with the binding of immune complexes to their receptors may be an effective means for the prevention and treatment of rheumatoid arthritis complicated with osteoporosis.