Korczowska Izabela, Olewicz-Gawlik Anna, Trefler Jakub, Hrycaj Paweł, Krzysztof Łacki Jan
Department of Rheumatology and Clinical Immunology, University of Medical Sciences in Poznań, Przybyszewskiego 39., 60-356 Poznań, Poland.
Clin Rheumatol. 2008 May;27(5):565-72. doi: 10.1007/s10067-007-0747-2. Epub 2007 Oct 2.
Rheumatoid arthritis (RA) is frequently complicated by peri-articular and generalized osteoporosis due to increased bone resorption by activated osteoclasts. Pro-inflammatory cytokines, such as TNF-alpha, interleukin 1 (IL1), and interleukin 6 (IL6) are thought, among other factors, to be directly responsible for this extra-articular complication of RA. Glucocorticoids (GCS) commonly prescribed in RA due to their strong anti-inflammatory effect are also well known for causing secondary osteoporosis during a prolonged use. An influence of low-dose GCS therapy (8.7 mg per day) on a bone turnover in female RA patients with or without previous history of GCS treatment was investigated by measuring bone mineral content (BMC), bone mineral density (BMD), and various biochemical markers of inflammation and bone metabolism in comparison to results obtained from: (1) RA patients who have not been treated with GCS and (2) the control group of healthy individuals. Sixty-two female patients with established active RA and 178 healthy individuals from the control group have been investigated. The RA patients were divided into three groups: 21 treated with GCS before the trial--these patients have continued GCS therapy using low doses during the observation; 21 with low-dose GCS therapy launched at the beginning of the trial; and 20 left without GCS treatment. All patients have been assessed twice: at the beginning and after 12 months of observation. BMC and BMD have been measured in all patients in a distal part of forearm. Additionally, several different biochemical markers of osteoporosis and inflammation have been determined. We did not notice any increase in bone metabolism between RA patients receiving GCS therapy for the first time and those treated without GCS after 12 months of observation. Results of BMC, BMD osteocalcin level, total and bone alkaline phosphatase, carboxy-terminal collagen cross links, carboxy-terminal propeptides of type 1 collagen, deoxypyridynoline, and calcium/creatinine ratio were comparable in both groups at the end of the study. There was a significant decrease of the level of IL-6 in patients who had GCS therapy launched at the beginning of observation (p<0.01). However, levels of C-reactive protein (CRP) and alpha1-acid-glycoprotein (AGP) have not changed; the level of ESR dropped significantly (p<0.05) in this group. In contrast, in the group of patients with the previous history of prolonged GCS treatment receiving low doses of GCS during the trial, statistically significant increase of CRP and AGP could be observed (p<0.05) along with further significant worsening of the primary low BMD (p<0.05). Based on the obtained data, we came to the conclusion that anti-inflammatory effect of the low-dose GCS therapy in RA patients without previous history of their use may balance their direct negative effect on BMC and BMD. In this group of RA patients, benefits resulting from the 12-month GCS therapy prevail over adverse effects, even if calcium with vitamin D3 supplementation, biphosphonians, or estrogens have not been introduced. On the other hand, low-dose GCS therapy could have no benefit for RA patients with the previous history of their prolonged use, as a rise of markers of inflammation and bone turnover, resulting in the further bone loss, has been observed.
类风湿关节炎(RA)常因活化破骨细胞增加骨吸收而并发关节周围及全身性骨质疏松。除其他因素外,促炎细胞因子,如肿瘤坏死因子-α、白细胞介素1(IL1)和白细胞介素6(IL6)被认为是RA这种关节外并发症的直接原因。由于具有强大的抗炎作用,糖皮质激素(GCS)在RA治疗中常用,但长期使用会导致继发性骨质疏松也广为人知。通过测量骨矿物质含量(BMC)、骨矿物质密度(BMD)以及炎症和骨代谢的各种生化标志物,并与以下结果进行比较,研究了低剂量GCS治疗(每天8.7毫克)对有或无GCS治疗史的女性RA患者骨转换的影响:(1)未接受GCS治疗的RA患者;(2)健康个体对照组。研究了62例确诊为活动性RA的女性患者和178名来自对照组的健康个体。RA患者分为三组:21例在试验前接受GCS治疗——这些患者在观察期间继续使用低剂量GCS治疗;21例在试验开始时开始低剂量GCS治疗;20例未接受GCS治疗。所有患者均进行了两次评估:观察开始时和观察12个月后。对所有患者的前臂远端进行了BMC和BMD测量。此外,还测定了几种不同的骨质疏松和炎症生化标志物。观察12个月后,我们未发现首次接受GCS治疗的RA患者与未接受GCS治疗的患者之间骨代谢有任何增加。研究结束时,两组患者的BMC、BMD、骨钙素水平、总碱性磷酸酶和骨碱性磷酸酶、羧基末端胶原交联、Ⅰ型胶原羧基末端前肽、脱氧吡啶啉以及钙/肌酐比值结果相当。在观察开始时接受GCS治疗的患者中,IL-6水平显著降低(p<0.01)。然而,C反应蛋白(CRP)和α1-酸性糖蛋白(AGP)水平未改变;该组血沉水平显著下降(p<0.05)。相比之下,在试验期间接受低剂量GCS治疗且有长期GCS治疗史的患者组中,可观察到CRP和AGP有统计学意义的增加(p<0.05),同时原发性低BMD进一步显著恶化(p<0.05)。根据获得的数据,我们得出结论,对于无GCS使用史的RA患者,低剂量GCS治疗的抗炎作用可能会抵消其对BMC和BMD的直接负面影响。在这组RA患者中,即使未补充钙和维生素D3、双膦酸盐或雌激素,12个月的GCS治疗带来的益处也超过了不良反应。另一方面,低剂量GCS治疗对有长期使用史的RA患者可能没有益处,因为观察到炎症和骨转换标志物升高,导致进一步的骨质流失。