Post Graduate Institute of Medicine, Colombo, Sri Lanka.
UCL Department of Nephrology, Royal Free Hospital, University College London, London, UK.
J Trace Elem Med Biol. 2022 Jan;69:126899. doi: 10.1016/j.jtemb.2021.126899. Epub 2021 Nov 12.
Selenium is a key component in multiple enzyme systems, and dialysis patients with lower levels have been reported to have increased mortality. Low selenium levels were commonly reported in historic hemodialysis patients, but not in recent studies. There have been very few studies in peritoneal dialysis (PD) patients, and with the increasing age and frailty of our PD population we wished to review factors associated with lower selenium in PD patients.
DESIGN & METHODS: We retrospectively reviewed plasma selenium, normal laboratory >0.8 umol/L, measurements from a cohort of PD patients, attending for routine peritoneal membrane assessments, along with measurement of dialysis adequacy (Kt/Vurea), and normalized nitrogen appearance rate (nPNA) and bioimpedance measured extracellular water (ECW)/total body water (TBW), and skeletal muscle mass indexed for height (SMMI).
The median plasma selenium was 0.84 (IQR-0.72-1.01) umol/L in 406 PD patients, 61.1 % male, mean age 59.0 ± 15.5 years, 44.9 % diabetic with 15.8 % designated as clinically frail (CFS). 41.4 % had selenium deficiency (<0.8 umol/L), and was more common with increasing CFS (χ2-6.8, p < 0.009), comorbidity grade(χ2-26.74, p < 0.001).Plasma selenium correlated with serum total protein (TP) (r = 0.352), albumin (r = 0.358), nPNA (r = 0.263), and negatively with ECW/TBW (r= -0.321) all p < 0.001, and positively with SMMI (rho = 0.109, p = 0.03). On multivariable analysis selenium was independently associated with TP (β 0.799 ± 0.15,95 % confidence limits (95CL) (0.505-1.093), p=<0.001), and negatively with C reactive protein (CRP) (β -0.02 ± 0.01, (95CL -0.047 to -0.005) p = 0.01), and ECW/TBW (β -1.499 ± 0.42 (95CL -2.33 to -0.666) p=<0.001).
Compared to recent studies in hemodialysis patients, we report a 41 % prevalence for low selenium levels. Plasma selenium was positively associated with total serum protein, and negatively with CRP and ECW/TBW. Thus, lower selenium concentrations were linked to reduced dietary protein intake, and increasing frailty, inflammation and ECW/TBW ratios.
硒是多种酶系统的关键组成部分，据报道，水平较低的透析患者死亡率增加。历史上血液透析患者的硒水平较低，但最近的研究并非如此。腹膜透析（PD）患者的研究很少，随着我们 PD 患者年龄的增长和虚弱程度的增加，我们希望回顾与 PD 患者硒水平较低相关的因素。
我们回顾性分析了 406 名 PD 患者的血浆硒水平（0.84 [IQR-0.72-1.01] μmol/L），这些患者接受了常规腹膜膜评估，并测量了透析充分性（Kt/Vurea）、标准化氮出现率（nPNA）和生物阻抗测量细胞外水（ECW）/总体水（TBW）以及身高指数化的骨骼肌质量（SMMI）。
406 名 PD 患者中，61.1%为男性，平均年龄 59.0±15.5 岁，44.9%为糖尿病患者，15.8%被指定为临床虚弱（CFS）。41.4%的患者存在硒缺乏症（＜0.8 μmol/L），且随着 CFS 的增加而更为常见（χ2-6.8，p＜0.009），合并症程度（χ2-26.74，p＜0.001）。血浆硒与血清总蛋白（TP）（r=0.352）、白蛋白（r=0.358）、nPNA（r=0.263）呈正相关，与 ECW/TBW 呈负相关（r=-0.321），均p＜0.001，与 SMMI 呈正相关（rho=0.109，p=0.03）。多变量分析显示，硒与 TP 独立相关（β0.799±0.15，95%置信区间（95CL）（0.505-1.093），p＜0.001），与 C 反应蛋白（CRP）负相关（β-0.02±0.01，（95CL-0.047 至-0.005），p=0.01），与 ECW/TBW 负相关（β-1.499±0.42（95CL-2.33 至-0.666），p＜0.001）。
与最近血液透析患者的研究相比，我们报告了 41%的低硒血症患病率。血浆硒与总血清蛋白呈正相关，与 CRP 和 ECW/TBW 呈负相关。因此，较低的硒浓度与减少膳食蛋白质摄入以及增加虚弱、炎症和 ECW/TBW 比值有关。
