Pallidal Index as Biomarker of Manganese Brain Accumulation and Associated with Manganese Levels in Blood: A Meta-Analysis

• Published in: PloS one Vol. 9; no. 4; p. e93900
• Main Authors: Li, Shao-Jun, Jiang, Li, Fu, Xue, Huang, Shuang, Huang, Yan-Ni, Li, Xiang-Rong, Chen, Jing-Wen, Li, Yong, Luo, Hai-Lan, Wang, Fang, Ou, Shi-Yan, Jiang, Yue-Ming
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.04.2014; Public Library of Science (PLoS)
• Subjects: Accumulation; Archives & records; Basal Ganglia Diseases - chemically induced; Basal Ganglia Diseases - pathology; Bioindicators; Biology and Life Sciences; Biomarkers; Blood; Brain; Brain Chemistry; Brain research; Clinical Trials as Topic; Confidence intervals; Correlation; Correlation analysis; Correlation coefficient; Correlation coefficients; Criteria; Data processing; Disease; Environmental health; Exposure; Feasibility studies; Globus Pallidus - chemistry; Humans; Magnetic Resonance Imaging - methods; Manganese; Manganese - blood; Manganese - pharmacokinetics; Manganese - toxicity; Manganese Compounds - pharmacokinetics; Maximum Allowable Concentration; Medical ethics; Medicine and Health Sciences; Meta-analysis; Metallurgy; Neurotoxicity; NMR; Nuclear magnetic resonance; Occupational Exposure; Oxides - pharmacokinetics; Oxides - toxicity; Physical Sciences; Public health; Publication Bias; Randomized Controlled Trials as Topic; Reproducibility of Results; Retrospective Studies; Rodents; Sensitivity analysis; Sensitivity and Specificity; Spectrum analysis; Studies; Toxicology; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0093900

The current study was designed to evaluate the sensitivity, feasibility, and effectiveness of the pallidal index (PI) serving as a biomarker of brain manganese (Mn) accumulation, which would be used as an early diagnosis criteria for Mn neurotoxicity. The weighted mean difference (WMD) of the PI between control and Mn-exposed groups was estimated by using a random-effects or fixed-effects meta-analysis with 95% confidence interval (CI) performed by STATA software version 12.1. Moreover, the R package "metacor" was used to estimate correlation coefficients between PI and blood Mn (MnB). A total of eight studies with 281 occupationally Mn-exposed workers met the inclusion criteria. Results were pooled and performed with the Meta-analysis. Our data indicated that the PI of the exposed group was significantly higher than that of the control (WMD: 7.76; 95% CI: 4.86, 10.65; I2 = 85.7%, p<0.0001). A random effects model was used to perform meta-analysis. These findings were remarkably robust in the sensitivity analysis, and publication bias was shown in the included studies. Seven out of the eight studies reported the Pearson correlation (r) values. Significantly positive correlation between PI and MnB was observed (r = 0.42; 95% CI, 0.31, 0.52). PI can be considered as a sensitive, feasible, effective and semi-quantitative index in evaluating brain Mn accumulation. MnB can also augment the evaluation of brain Mn accumulation levels in the near future. However, the results should be interpreted with caution.