Systematic Review and Meta-Analysis on Heavy Metals and Trace Elements in Mild Cognitive Impairment

Area of Science:

• Neuroscience
• Environmental Health
• Biochemistry

Background:

• Mild cognitive impairment (MCI) is an early stage of neurodegenerative diseases.
• Significant heterogeneity exists in heavy metal and trace element levels among MCI patients.
• Understanding these elemental differences is crucial for early diagnosis and intervention.

Purpose of the Study:

• To systematically review and meta-analyze studies on heavy metal and trace element levels in MCI patients compared to healthy controls.
• To identify specific elements with altered concentrations in MCI.
• To explore potential diagnostic or therapeutic targets based on elemental profiles.

Main Methods:

• Systematic literature search of PubMed, Web of Science, and Chinese academic databases (2000-present).
• Inclusion of 43 case-control/cross-sectional studies involving 16,743 samples.
• Meta-analysis using a random-effects model to calculate standardized mean differences (SMD) for 12 elements.

Main Results:

• Elevated levels of Aluminum (Al), Arsenic (As), Cadmium (Cd), Copper (Cu), and Lead (Pb) were observed in MCI patients.
• Significantly lower levels of Selenium (Se) and Zinc (Zn) were found in MCI patients.
• No significant differences were noted for Iron (Fe) and Magnesium (Mg), among others.

Conclusions:

• Specific heavy metal and trace element profiles are associated with mild cognitive impairment.
• Altered levels of Al, As, Cd, Cu, Pb, Se, and Zn suggest their potential role in MCI pathogenesis.
• Monitoring and modulating these element levels could represent novel targets for early intervention strategies in neurodegenerative diseases.