Jiang Chunjie, Yi Junlin, Lai Jiahui, Wen Luona, Zhong Xiaoshi, Tan Rongshao, Liu Yun
Department of Clinical Nutrition, Guangzhou Red Cross Hospital, Jinan University, Guangzhou, Guangdong Province, China.
Department of Cardiovascular Medicine, Hunan University of Medicine General Hospital, Huaihua, China.
Kidney Med. 2025 Jun 17;7(8):101050. doi: 10.1016/j.xkme.2025.101050. eCollection 2025 Aug.
RATIONALE & OBJECTIVE: A complex relationship exists between blood manganese (Mn) and hemoglobin concentrations in patients with chronic kidney disease (CKD), with associations observed in patients not treated with dialysis and those on maintenance hemodialysis. This study aimed to elucidate this relationship using a large sample of adult patients with CKD from the National Health and Nutrition Examination Survey (NHANES) database.
This was a across-sectional study.
SETTING & STUDY POPULATIONS: We included data of 1,016 adult patients with CKD from the NHANES database between 2015 and 2018.
We included participants with CKD who were aged ≥18 years, not pregnant, and had available data on hemoglobin, Mn levels, and other relevant covariates.
Hemoglobin and blood Mn levels in patients with CKD.
Whole-blood Mn concentrations were analyzed using quadrupole inductively coupled plasma mass spectrometry. The statistical analyses included univariate and multivariate linear and binary logistic regression models, along with generalized additive models and smooth curve fitting to explore nonlinearity, which was further examined using a 2-piece-wise linear regression model.
After adjusting for age; sex; race/ethnicity; body mass index; smoking status; and levels of albumin, creatinine, ferritin, and transferrin receptor, a nonlinear (U-shaped) association was observed between Mn levels and anemia risk ( < 0.001 for nonlinearity). Specifically, lower Mn levels (<194.2 nmol/L) were negatively associated with anemia (OR, 0.984; 95% CI, 0.979-0.990; < 0.001), whereas higher Mn levels (>194.2 μmol/L) showed a positive association (OR, 1.006; 95% CI, 1.001-1.011; = 0.021).
Even with multivariate model analysis, we failed to establish a causal relationship between Mn levels and anemia in patients with CKD.
These findings suggest that Mn may have a dual role in the pathophysiology of anemia in patients with CKD.
慢性肾脏病（CKD）患者的血锰（Mn）与血红蛋白浓度之间存在复杂关系，在未接受透析治疗的患者和维持性血液透析患者中均观察到这种关联。本研究旨在利用来自国家健康与营养检查调查（NHANES）数据库的大量成年CKD患者样本阐明这种关系。
这是一项横断面研究。
我们纳入了2015年至2018年期间NHANES数据库中1016例成年CKD患者的数据。
我们纳入了年龄≥18岁、非妊娠且有血红蛋白、锰水平及其他相关协变量数据的CKD患者。
CKD患者的血红蛋白和血锰水平。
采用四极杆电感耦合等离子体质谱法分析全血锰浓度。统计分析包括单变量和多变量线性及二元逻辑回归模型，以及广义相加模型和平滑曲线拟合以探索非线性关系，并使用两段式线性回归模型进一步检验。
在调整年龄、性别、种族/民族、体重指数、吸烟状况以及白蛋白、肌酐、铁蛋白和转铁蛋白受体水平后，观察到锰水平与贫血风险之间存在非线性（U形）关联（非线性P<0.001）。具体而言，较低的锰水平（<194.2 nmol/L）与贫血呈负相关（比值比[OR]，0.984；95%置信区间[CI]，0.979 - 0.990；P<0.001），而较高的锰水平（>194.2 μmol/L）则呈正相关（OR，1.006；95% CI，1.001 - 1.011；P = 0.021）。
即使进行了多变量模型分析，我们仍未能在CKD患者的锰水平与贫血之间建立因果关系。
这些发现表明，锰在CKD患者贫血的病理生理过程中可能具有双重作用。
