类风湿关节炎患者体质指数与疾病活动性的相关性研究

Relationship between body mass index and disease activity in rheumatoid arthritis

目的探讨类风湿关节炎(RA)患者体质指数(BMI)与疾病活动性之间的相关性。方法收集620例确诊为RA的患者,分为体重过低(BMI1)组:110例(17.7%);体重正常(BMI2)组:354例(57.1%);超重(BMI3)组:156例(25.2%,其中肥胖者占3.0%),比较各组临床特征及实验室指标之间的异同,分析RA患者BMI与疾病活动性之间的相关性。结果①BMI1、BMI2、BMI3三组首发症状为膝、踝及髋负重关节炎的患者比例分别为23.6%、28.0%、44.2%,首发症状为手、足等外周小关节炎的患者比例分别为76.4%、72.0%、55.8%(P<0.001);BM11组较BMI2、BMI3组双手X线骨破坏较重、关节功能差(P<0.001);三组在是否使用激素及改变病情抗风湿药、抗环瓜氨酸多肽(CCP)抗体阳性率的比较差异无统计学意义;②红细胞沉降率(ESR)、C反应蛋白(CRP)、关节肿胀数(SJC)、关节压痛数(TJC)、健康评估问卷(HAQ)评分、疾病活动指数28(DAS28)在三组间差异有统计学意义(p<0.05),BMI1组较其他组ESR、CRP、DAS28、HAQ评分高,SJC及TJC数目多(P<0.05);③相关性分析显示:BMI与RA患者的ESR(r_s=-0.174,P<0.001)、CRP(r_s=-0.138,P=0.001)、DAS28(r_s=-0.155,P<0.001)、SJC(r_s=-0.110,P=0.006)、TJC(r_s=-0.123,P=0.002)、关节功能(r_s=-0.102,P=0.012),以及双手X线分期(r_s=-0.113,P=0.007)呈负相关性,与类风湿因子、疼痛VAS评分、HAQ评分、病程等指标间无相关性;④多元线性回归显示:BMI为CRP和ESR的影响因素。结论低或正常BMI的RA患者发病以小关节为主,而高BMI患者以负重关节发病比率增高;低BMI的RA患者有着更高CRP、ESR及疾病活动性,而高BMI对疾病活动性及骨破坏可能有保护作用。

Objective To explore the relationship between body mass index（BMI） and disease activity in rheuma- toid arthritis（RA）. Methods 620 patients with RA were divided into three groups,low weight （BMI1） group of 110 cases,normal body weight（BMI2） group of 354 cases and Overweight（ BMI3 ） group of 156 cases. The clinical features among the three groups were investigated and the correlation between BMI and disease activity was dis- cussed. Results ① Percentages of first starting symptom with bearing arthritis among BMI1, BMI2 and BMI3 groups were 23.6%, 28.0% and 44. 2%, while those of the first signs with peripheric arthritis were 76.4%, 72.0% and 55.8% （P 〈0. 001）. Compared with BMI2 and BMI3 groups,BMI1 group had more severe bone de- struction and joint function（ P 〈 0. 001 ）. There was no significant difference in anti-CCP antibody positivity, the use of disease-modifying antirheumatic drug and steroid among three groups ; ② Differences in erythrocyte sedimentation rate （ ESR）, C-reactive protein （ CRP）, tender joint count （ TJC ）, swollen joint count （ SJC ）, health assessment ques- tionnaire（ HAQ）, disease activity score in 28 joints（ DAS28 ） among the three groups were all significantly different （P 〈 0. 05 ）. ESR, CRP, DAS28 and HAQ in BMI1 group were higher than those of the other two groups, and BMI1 group had more TJC and SJC than the other two groups ; ③ The correlation analysis showed that BMI was negatively correlated with ESR （ r, = - 0. 174, P 〈 0. 001 ）, CRP （ rs = - 0. 138, P = 0. 001 ）, DAS28 （ r, = - 0. 155, P 〈 0. 001）,SJC （r, = -0. 110,P =0. 006）,TJC（rs = -0. 123,P =0. 002）,bone destruction （rs = -0. 102,P = 0. 012 ）, and X-ray stages （r, = -0. 113 ,P = 0. 007 ） ; ④ Linear regression analysis showed that BMI was the factor for the change of CRP and ESR in RA. Conclusion Low and normal weight patients are more prone to take pe- ripheral arthritis as the first symptom, with the increase of BMI, the incidence ratio of bearing arthritis increases. Low BMI appears to be associated with higher ESR, CRP and DAS28, high BMI may be a protective factor for dis- ease activity and bone destruction.