Association of Circulating Magnesium Levels in Patients With Alzheimer's Disease From 1991 to 2021: A Systematic Review and Meta-Analysis.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of observational case-control studies.
PubMed 35082658 · doi:10.3389/fnagi.2021.799824
What was done
Authors conducted a systematic review and meta-analysis of 21 studies published between 1991 and 2021 (searched in PubMed, Web of Science, CNKI, and Wanfang Data) comparing magnesium levels between Alzheimer's disease (AD) patients and healthy controls (HCs). Blood analyses (serum and plasma) included 1,112 AD patients and 1,001 HCs; cerebrospinal fluid (CSF) analyses included 284 AD patients and 117 HCs.
What was found
Serum and plasma magnesium levels were significantly reduced in AD patients compared with healthy controls (standardized mean difference [SMD] = -0.89; 95% CI [-1.36, -0.43]; P = 0.000). The difference in CSF magnesium between AD and HCs was not statistically significant (SMD = -0.16; 95% CI [-0.50, 0.18]; P = 0.364). Across combined blood and CSF measurements, circulating magnesium was significantly lower in AD patients (SMD = -0.74; 95% CI [-1.13, -0.35]; P = 0.000).
Why it matters
This review synthesizes 30 years of data to establish that circulating peripheral magnesium concentrations are consistently depressed in patients with Alzheimer's disease compared to healthy peers.
Limits
All included data are observational and cross-sectional, which cannot establish causality or determine whether lower magnesium is a cause or consequence of disease. The CSF sample size was relatively small (284 cases, 117 controls). The abstract does not provide heterogeneity statistics or account for confounding factors such as dietary intake, kidney function, or medication use.
Cited by
- supports A systematic review showed that individuals with Alzheimer's disease have significantly lower plasma magnesium levels compared to healthy controls.