Kinjo Mitsuyo, Setoguchi Soko, Solomon Daniel H
Teine Keijinkai Hospital, Teine-ku Sapporo city, Japan.
J Rheumatol. 2007 Oct;34(10):1971-5. Epub 2007 Sep 15.
Several studies suggest that bone mineral density (BMD) is reduced in rheumatoid arthritis (RA). However, it is unclear whether this relationship holds in a representative community-based typical RA population. We examined the relationship between BMD and RA in a representative US population-based sample from the Third National Health and Nutrition Examination Survey (NHANES III: 1988-1994).
We selected subjects over age 60 with RA from NHANES III using previously described methods. Femoral neck BMD (FN-BMD) measured by dual-energy x-ray absorptiometry was compared for the RA (n = 106) and non-RA cohorts (n = 4,277). Multivariable linear regression models included known risk factors for osteoporosis. Further adjusted analyses compared the BMD among subgroups of patients with RA, such as those taking methotrexate (MTX), those with positive rheumatoid factor (RF), and those with elevated C-reactive protein (CRP).
Patients with RA more frequently reported poor health, a history of falling, cognitive impairment, early menopause, a history of chronic obstructive lung disease, higher total calcium intake, and thiazide use than the non-RA subjects (all p < 0.05). Adjusted FN-BMD was similar between the patients with RA (0.71 g/cm2) and non-RA subjects (0.72 g/cm2; p = 0.5). Among patients with RA, reduced BMD tended to be seen with MTX use (0.60 g/cm2, p = 0.07), CRP above 1 mg/dl (0.66 g/cm2, p = 0.09), and positive RF in female patients (0.68 g/cm2, p = 0.056). However, none of these findings reached statistical significance.
Among a US population-based representative sample, FN-BMD was similar in RA and non-RA patients. Several characteristics of patients with RA may be associated with reduced BMD.
多项研究表明类风湿关节炎（RA）患者的骨密度（BMD）会降低。然而，这种关系在以社区为基础的典型RA人群中是否成立尚不清楚。我们在第三次全国健康与营养检查调查（NHANES III：1988 - 1994）中一个具有代表性的美国人群样本中研究了BMD与RA之间的关系。
我们使用先前描述的方法从NHANES III中选取了60岁以上的RA患者。通过双能X线吸收法测量的股骨颈骨密度（FN - BMD）在RA队列（n = 106）和非RA队列（n = 4277）之间进行比较。多变量线性回归模型纳入了已知的骨质疏松风险因素。进一步的校正分析比较了RA患者亚组之间的骨密度，如服用甲氨蝶呤（MTX）的患者、类风湿因子（RF）阳性的患者以及C反应蛋白（CRP）升高的患者。
与非RA受试者相比，RA患者更频繁地报告健康状况差、有跌倒史、认知障碍、早绝经、慢性阻塞性肺疾病史、总钙摄入量较高以及使用噻嗪类药物（所有p < 0.05）。RA患者（0.71 g/cm²）和非RA受试者（0.72 g/cm²；p = 0.5）的校正后FN - BMD相似。在RA患者中，使用MTX（0.60 g/cm²，p = 0.07）、CRP高于1 mg/dl（0.66 g/cm²，p = 0.09）以及女性患者RF阳性（0.68 g/cm²，p = 0.056）时骨密度往往降低。然而，这些发现均未达到统计学意义。
在一个具有代表性的美国人群样本中，RA患者和非RA患者的FN - BMD相似。RA患者的几个特征可能与骨密度降低有关。
