Evidence map›Paper›PMID 40251518›Full record

ArticleBMC endocrine disorders2025

Dietary iron intake is nonlinearly associated with the risk of diabetic retinopathy in adults with type 2 diabetes.

Xiaoyun Chen, Yihang Fu, Hongyu Si, Wenfei Li, Weimin Yang, Wei Xiao

Abstract read
In one paragraph

Article in BMC endocrine disorders, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Review
4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Xiaoyun Chen *State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Centre, Guangdong Provincial Key Laboratory of Ophthalmology and Vision Science, Guangdong Provincial Clinical Research Centre for Ocular Diseases, Sun Yat- Sen University, Guangzhou, China. chenxiaoyun@gzzoc.com.
Yihang Fu *State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Centre, Guangdong Provincial Key Laboratory of Ophthalmology and Vision Science, Guangdong Provincial Clinical Research Centre for Ocular Diseases, Sun Yat- Sen University, Guangzhou, China.
Hongyu SiState Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Centre, Guangdong Provincial Key Laboratory of Ophthalmology and Vision Science, Guangdong Provincial Clinical Research Centre for Ocular Diseases, Sun Yat- Sen University, Guangzhou, China.
Wenfei LiState Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Centre, Guangdong Provincial Key Laboratory of Ophthalmology and Vision Science, Guangdong Provincial Clinical Research Centre for Ocular Diseases, Sun Yat- Sen University, Guangzhou, China.
Weimin YangState Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Centre, Guangdong Provincial Key Laboratory of Ophthalmology and Vision Science, Guangdong Provincial Clinical Research Centre for Ocular Diseases, Sun Yat- Sen University, Guangzhou, China.
Wei XiaoState Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Centre, Guangdong Provincial Key Laboratory of Ophthalmology and Vision Science, Guangdong Provincial Clinical Research Centre for Ocular Diseases, Sun Yat- Sen University, Guangzhou, China. xiaow27@mail.sysu.edu.cn.

Funding

the Guangdong Basic and Applied Basic Research Foundation 2023A1515012192the Guangdong Basic and Applied Basic Research Foundation 2023A1515030108
6 · The paper itself

Abstract

objectiveTo elucidate the association between dietary iron intake and diabetic retinopathy (DR) in type 2 diabetes (T2D) patients.

methodsParticipants from the National Health and Nutrition Examination Survey (NHANES) 2005-2008 aged over 40 years with T2D were included. Dietary iron intake was estimated from standardised questionnaires. The presence of DR and vision-threatening DR (VTDR) was determined through retinal imaging. We used logistic regression to assess the relationship between iron intake and DR, and restricted cubic splines to reveal nonlinear links.

resultsThe study enrolled 1172 T2D adults. We found significant nonlinear associations between dietary iron intake and DR among females (P = 0.023), but not in males (P = 0.490). Compared with the lowest quartile of iron intake, the third quartile (13.2-18.1 mg/d) yielded significantly lower odds of developing DR (odds ratio [OR], 0.59; 95% CI, 0.39-0.90) and VTDR (OR, 0.42; 95% CI, 0.19-0.94). Stratified logistic analyses showed that medium-high iron intake was associated with lower risks of DR in females (OR, 0.44; 95% CI, 0.24-0.81), non-Hispanic Blacks (OR, 0.38; 95% CI, 0.17-0.85), and individuals with obesity (OR, 0.45; 95% CI, 0.25-0.82), high HbA1c (OR, 0.56; 95% CI, 0.34-0.93), long diabetes duration (OR, 0.40; 95% CI, 0.21-0.76) or low blood haemoglobin (OR, 0.17; 95% CI, 0.05-0.60).

conclusionDietary iron intake was nonlinearly negatively associated with the prevalence of DR and VTDR, showing protective effect against retinopathy of medium-high iron intake in T2D patients. Such associations significantly vary by multiple factors such as age, ethnicity, obesity and glycaemic control.

Indexed as

Diabetes Mellitus, Type 2Diabetic RetinopathyIron, DietaryAdultAgedCross-Sectional StudiesFemaleFollow-Up StudiesHumansMaleMiddle AgedNutrition SurveysPrognosisRisk FactorsIron, DietaryDiabetic retinopathyDietary iron intakeNHANESVision-threatening diabetic retinopathy

Identifiers

PMID40251518
PMCPMC12007315

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.