长透析龄腹膜透析患者腹膜钙化发生率及影响因素

Prevalence and influencing factors of peritoneal calcification in patients with long peritoneal dialysis duration

目的探讨长透析龄腹膜透析（PD）患者腹膜钙化的发生率及相关影响因素，分析腹膜钙化与血管钙化的相关关系。方法选择在北京大学人民医院肾内科接受腹膜透析4年以上并规律随访的患者进行横断面研究。应用腹部CT平扫判断患者腹膜钙化及腹主动脉钙化的发生情况。按照是否存在腹膜钙化和透析龄分组。收集患者人口学及临床资料、钙磷代谢【包括血钙、磷、碱性磷酸酶（ALP）、甲状旁腺激素（iPTH）等]、透析充分性等指标。用Logistic回归模型法分析腹膜钙化的影响因素；用Spearman相关分析分析腹膜钙化与血管钙化的相关性。结果共79例PD患者被纳入研究，男32例（40．5％），平均年龄（58．7±13．1）岁，中位透析龄77．25（58．00，88．00）个月，主要原发病为慢性肾小球肾炎（46．8％），其次为糖尿病肾病（30．4％）。6例患者存在腹膜钙化，占7．6％，77例患者伴有不同程度的腹膜增厚（97．5％）。腹膜钙化在透析龄4年以上者中的发生率为7．6％，6年以上者为10.3％，8年以上者为18．8％，10年以上为40．O％，呈逐年上升趋势。与无腹膜钙化组相比，腹膜钙化组患者服用维生素D剂量较大（P〈0．001），血三酰甘油水平较低（P=0．041）。与透析龄〈9年组相比，透析龄≥9年组患者腹膜钙化患者比例较高（P=0．013）。Logistics回归分析结果显示，服用大剂量活性维生素D是腹膜钙化发生的独立危险因素（B=2．667，OR=14．394，95％CI1．655—125．165，P=0．016）。腹主动脉钙化发生率为93．7％。Spearman相关分析结果显示，腹膜钙化与血管钙化间无相关性（r=0．70，P=0．542）。结论腹膜钙化在长透析龄PD人群中发生率较低，可能与服用大剂量活性维生素D、长透析龄相关。

Objective To investigate the prevalence and related factors of peritoneal calcification in peritoneal dialysis （PD） patients with long dialysis duration, and to explore the relationship between peritoneal calcification and vascular calcification. Methods This cross-section study enrolled PD patients who had received PD for more than 4 years in Peking University People＇s Hospital. Peritoneal calcification and abdominal aortic calcification were reviewed by CT scan. Demographic data, clinical characteristics, laboratory data including calcium phosphorus metabolism indexes （Ca, P, ALP and iPTH） and PD adequacy were collected. The influencing factors of peritoneal calcification were analyzed by Logistic regression analysis. The correlation between peritoneal calcification and abdominal aortic calcification were tested by Spearman correlation analysis. SPSS 19.0 was used for statistical analysis. Results （1） Seventy- nine PD patients were enrolled： 32 males （40.5%）; mean age was （58.7±13.1） years and average PD duration was 77.25（58.00, 88.00） months. The major primary diseases were glomerulonephritis （46.8%） and diabetic nephropathy （30.4%）. （2） 6 patients （7.6%） had CT-detectable peritoneal calcification. 77（97.5%） patients were found with various degrees of peritoneal thickening. The prevalence of peritoneal calcification was 7.6% in patients with PD duration more than 4 years, 10.3% in patients with PD duration more than 6 years, 18.8% in patients with PD duration more than 8 years and 40.0% in patients with PD duration more than 10 years, showing an increasing trend. Compared with non-peritoneal calcification group, the patients in peritoneal calcification group received higher doses of Vitamin D （P 〈 0.001） and lower triglyceride levels （P=0.041）. The patients were divided into two groups according to whether dialysis duration was longer than 9 years, and the proportion of patients with long PD duration in peritoneal calcification group was higher （P=0.013）. Logistic regression analysis showed that PD duration, calcium and phosphorus metabolism indexes were not independent risk factors of peritoneal calcification. High vitamin D dose was an independent risk factor for peritoneal calcification （B=2.667, 0R=14.394, 95% CI 1.655- 125.165, P=0.016）. （3） 74 patients were found with abdominal aortic calcification in different degrees, and the prevalence rate of abdominal aortic calcification was 93.7%. Spearman correlation analysis showed that there was no correlation between peritoneal calcification and vascular calcification （r=0.70, P=0.542）. Conclusions The prevalence of peritoneal calcification in long PD duration patients is low. Peritoneal calcification may be associated with high Vitamin D dose and long PD duration.