Affiliations 

  • 1 Dr. Razinah Sharif, Programme of Nutritional Science, School of Healthcare Sciences, Faculty of Health Science, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur 50300, Malaysia, Telephone: +603-9289-7459, Fax number: +603-2694-7621, Email address: razinah@ukm.edu.my
J Nutr Health Aging, 2017;21(5):539-545.
PMID: 28448084 DOI: 10.1007/s12603-016-0759-1

Abstract

BACKGROUND: A cross sectional study was conducted in a group of 317 subjects older than 60 in Malaysia, aimed to determine risk factors associated with cognitive impairment in older adults, focusing on trace elements and DNA damage.

METHOD: Cognitive decline was determined by Montreal Cognitive Assessment (MoCA). Oxidative stress markers (malondialdehyde-MDA and superoxide dismutase-SOD) were determined and DNA damage was assayed using Alkaline Comet Assay. Toenail samples were taken and analyzed using ICP-MS to determine trace element levels.

RESULTS: A total of 62.1 % of subjects had cognitive impairment. Subjects with cognitive impairment had significantly higher levels of MDA and DNA damage as compared to the group with normal cognitive function; MDA (2.07 ± 0.05 nmol/L vs 1.85 ± 0.06 nmol/L) (p<0.05) and DNA damage (% Tail Density, 14.52 ± 0.32 vs 10.31 ± 0.42; Tail Moment, 1.79 ± 0.06 vs 1.28 ± 0.06) (p<0.05 for all parameters). However, the level of SOD among subjects with cognitive impairment (6.67 ± 0.33 u.e/min/mg protein) was lower than the level among those with normal cognitive functions (11.36 ± 0.65 u.e/min/mg protein) (p<0.05). Multiple logistic regression revealed the predictors for cognitive impairment among the subjects were DNA damage (Adjusted odd ratio [OR], 1.37; 95% confidence interval [CI], 1.18-1.59), level of trace elements in toenails namely, lead (OR, 2.471; CI, 1.535-3.980) and copper (OR, 1.275; CI, 1.047-1.552) (p<0.05).

CONCLUSION: High levels of lead and copper can lead to increase in oxidative stress levels and are associated with DNA damage that eventually could be associated with cognitive decline.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.