Zhang Liling, Yin Defeng, Zhu Tingting, Geng Lei, Gan Linwang, Ou Santao, Fan Di
Department of Nephrology, The Affiliated Hospital, Southwest Medical University, Luzhou, China.
Department of Emergency, The Affiliated Hospital, Southwest Medical University, Luzhou, China.
Int Urol Nephrol. 2025 Jan;57(1):215-222. doi: 10.1007/s11255-024-04157-8. Epub 2024 Jul 24.
An increasing evidence suggested that chronic kidney disease (CKD) is closely related to oxidative stress, and dietary antioxidant intake can serve as a primary preventive measure for CKD. However, the relationship between composite dietary antioxidant index (CDAI) and renal anemia is not well understood. We postulated that elevated CDAI levels would be inversely related to a higher likelihood of renal anemia. The standardized calculation of CDAI was performed to investigate the relationship between them by a binary regression model. A non-linear relationship was examined through restricted cubic spline curves, and then pinpointed the inflection point. Subgroup analysis was then used to assess the robustness of the model. Finally 5880 participants were included in the study and a notable correlation between CDAI and renal anemia was found (P < 0.0001). In the multivariate linear regression model with adjustment for all confounding variables, the odds ratio (OR) and 95% confidence interval (CI) was 0.96 (0.94, 0.98; P < 0.0001), A non-linear relationship between CDAI and renal anemia was explored through restricted cubic splines, with a inflection at 6.005. Before the inflection point, for each unit rise in CDAI, the prevalence of renal anemia decreased by 5.7%. Subgroup analysis showed no statistically significant differences in interactions between any subgroups (P > 0.05). Our findings indicated a non-linear negative correlation between CDAI and renal anemia. The causal relationship still needs to be further clarified through large-scale prospective studies.
越来越多的证据表明，慢性肾脏病（CKD）与氧化应激密切相关，饮食中摄入抗氧化剂可作为CKD的主要预防措施。然而，复合饮食抗氧化指数（CDAI）与肾性贫血之间的关系尚不清楚。我们推测，CDAI水平升高与肾性贫血的较高可能性呈负相关。通过二元回归模型对CDAI进行标准化计算，以研究它们之间的关系。通过受限立方样条曲线检验非线性关系，然后确定拐点。随后进行亚组分析以评估模型的稳健性。最终，5880名参与者纳入研究，发现CDAI与肾性贫血之间存在显著相关性（P < 0.0001）。在对所有混杂变量进行调整的多元线性回归模型中，比值比（OR）和95%置信区间（CI）为0.96（0.94，0.98；P < 0.0001），通过受限立方样条探索CDAI与肾性贫血之间的非线性关系，拐点为6.005。在拐点之前，CDAI每升高一个单位，肾性贫血的患病率下降5.7%。亚组分析显示，任何亚组之间的交互作用均无统计学显著差异（P > 0.05）。我们的研究结果表明CDAI与肾性贫血之间存在非线性负相关。因果关系仍需通过大规模前瞻性研究进一步阐明。
