Alzheimer’s Disease and Essential Metals and Metalloids: Hospital Based Case-Control Study

Abstract

Objectives There is some evidence that exposure to some metals and metalloids may be associated with an increased risk of Alzheimer's disease (AD). Some essential metals may promote beta-amyloid aggregation and plaque formation. The aim of the study was to estimate the concentration of essential metals and metalloids copper, zinc, manganese, and selenium in AD patients. Materials and methods A hospital-based case-control study of AD risk factors was performed between March 2018 and March 2020 in two Hospitals of Lithuanian University of Health Sciences. The cases (n=53) were patients aged 68–94 years with AD diagnosed within the study period. The controls (n=217) were patients aged 53-93 years free from AD and dementia undergoing treatment for eye diseases. Copper and zinc in plasma, and manganese and selenium in blood were determined by inductively coupled plasma mass spectrometry. The results are presented in mean values (± standard deviations) that compared using t test. The level of statistical significance was set at 0.05. All reported p-values are 2-sided. Results In AD patients, plasma zinc and blood selenium were significantly lower compared to controls: plasma zinc was 66.0±13.42 µg/dl and 82.53±30.54 µg/dl (p <0.001), blood selenium was 10.71±2.37 µg/dl and 14.38±4.65 µg/dl (p<0.001), respectively. Meanwhile, blood manganese in AD patients was significantly higher than that in controls (1.17±0.49 µg/dl and 1.03±0.30 µg/dl, p<0.01). There was no difference in plasma copper concentration between cases and controls (102.81±21.06 and 108.46±21.37, p>0.05). Conclusions The data obtained show that manganese content in blood of patients with Alzheimer disease is greater compared to controls while zinc and selenium concentration is lower.