肌少症和骨质疏松对类风湿关节炎患者脊柱骨质疏松性骨折的协同影响

目的探讨肌少症和骨质疏松(OP)对RA患者脊柱骨质疏松性骨折(OPF)发生的协同影响.方法选择389例住院的RA患者和同期156例年龄、性别相匹配的健康人,采用双能X线吸收测量(DEXA)法测定腰椎和髋部的骨密度(BMD),采用生物电阻抗法测定四肢骨骼肌质量,摄脊柱X线正侧位片并以半定量法进行脊柱骨折的判定.统计学方法:2组间计量资料比较采用t检验,组间率的比较采用x2检验,2项分类资料的多元回归分析采用Logistic回紧(backward LR法)分析.结果RA患者各测定部位BMD均低于对照组(P<0.01),RA组骨质疏松发生率(128/389,32.9%)高于对照组(20/156,12.8%),χ^2=22.706,P<0.01];RA患者脊柱OPF发生率为21.6%(84/389),高于对照组中(3.8%,6/156),χ^2=25.439,P<0.01].RA患者中肌少症的发生率为54.8%,高于对照组(9.6%,15/156),χ^2=93.241,P<0.01];RA组肌少症合并骨质疏松的发生率(28.5%)高于对照组(5.8%),χ^2=118.110,P<0.01 ].不同骨量(骨量正常、骨量减少、骨质疏松)分组间RA患者脊柱OPF发生率的差异有统计学意义(χ^2=43.373,P<0.01),且呈现出随着骨量逐渐降低,脊柱OPF发生率逐渐升高的趋势(χ^2=43.003,P<0.01).伴肌少症的RA患者脊柱OPF发生率(27.2%,58/213)高于无肌少症的RA患者(14.8%,26/176),χ^2=8.833,P=0.003].根据骨质疏松和肌少症分组的3组间(1=无肌少症和骨质疏松;2=单纯肌少症或骨质疏松;3=肌少症合并骨质疏松)RA患者脊柱OPF发生率的差异有统计学意义(χ^2=33.832,P<0.01),且从第1组到第3组脊柱OPF的发生率有逐渐增高的趋势(χ^2=37.164,P<0.01).与未服用糖皮质激素(GC)组相比,服用GC组的RA患者具有更高的肌少症发生率(χ^2=7.136,P=0.008)、OP发生率(CI=10.900,P=0.004)和脊柱OPF发生率(χ^2=20.673,P<0.01).Logistic回归分析显示:高龄OR(95%CI)=1.069(1.038,1.101),P<0.01]、服用GCOR(95%CI)=3.169(1.679,5.984),P<0.01]、肌少症和骨质疏松OR(95%CI)=2.113(1.430,3.124),P<0.01]的同时存在为RA患者发生脊柱OPF的危险因素.结论RA患者肌少症、骨质疏松和脊柱OPF的发生率均明显增高,且肌少症和骨质疏松对RA患者脊柱OPF的发生具有协同作用.

Synergistic effect of sarcopenia and osteoporosis on spinal osteoporotic fracture in patients with rheumatoid arthritis

Objective To investigate the synergistic effect of sarcopenia and osteoporosis on the occurrence of spinal osteoporotic fracture(OPF)in patients with rheumatoid arthritis(RA).Methods A total of 389 hospitalized RA patients and 156 age and sex-matched normal subjects(control group)were recruited.Dual energy X-ray absorptiometry(DEXA)method was used to measure bone mineral density(BMD)of lumbar spine and hip,and bioelectrical impedance method was applied to determine skeletal muscle mass of limbs.X-ray examination of spin was conducted and spinal OPF was diagnosed according to semi-quality method.Student's t test was used for comparison of measurement date between the two groups,χ2 test was used for comparison of intergroup rates,and Logistic Regression(Backward LR)method was used for multivariate Regression analysis of binomial classification data.Results BMD of all test sites in RA patients was significantly lower than that in the control group(P<0.01).The incidence of total OP in RA group was significantly higher than that in the control group(32.9%vs 12.8%),χ2=22.706,P<0.01].A total of 84 patients with RA developed spinal OPF,with an incidence of 21.6%which was higher than that in the control group(3.8%),χ2=25.439,P<0.01].The incidence of sarcopenia in RA was 54.8%,significantly higher than that in the control group(9.6%),χ2=93.241,P<0.01].The incidence of sarcopenia combined with osteoporosis in RA group(28.5%)was significantly higher than that in the control group(5.8%),χ2=118.110,P<0.01].Comparison of the incidence of spinal OPF in RA patients among groups with different bone mass(normal bone mass,osteopenia,osteoporosis)showed that the incidence of spinal OPF among these groups was statistically different(χ2=43.373,P<0.01),and the incidence of spinal OPF increased along with the decrease of bone mass(χ2=43.003,P<0.01).The incidence of spinal OPF in RA patients with sarcopenia(27.2%,58/213)was significantly higher than that in RA patients without sarcopenia(14.8%,26/176),χ2=8.833,P=0.003].All participants were divided into three groups:group 1=no OP and sarcopenia,group 2=with sarcopenia or OP,group 3=both sarcopenia and OP.Difference of incidence of spine OPF in RA patients among three groups was statistically significant(χ2=33.832,P<0.01),and the incidence of spinal OPF raised gradually in group 1 and 3,(χ2=37.164,P<0.01).Incidences of sarcopenia,OP and spinal OPF in RA treated with glucocorticoid(GC)were higher than those in RA without GC(P<0.05,P<0.01).Results of logistic regression showed advanced ageOR(95%CI)=1.069(1.038,1.101),P<0.01],usage of GCOR(95%CI)=3.169(1.679,5.984),P<0.01]and sarcopenia combined with OPOR(95%CI)=2.113(1.430,3.124),P<0.01]were risk factors for spinal OPF in RA patients.Conclusion Incidences of sarcopenia,OP and spinal OPF in RA patients are higher than that in normal controls.Sarcopenia and OP have a synergistic effect on spinal OPF in RA patients.