Summary
This study examined whether older adults living in high-fluoride drinking-water areas experience greater cognitive impairment and whether the gene regulator DKK1 is involved in this process. Researchers assessed cognitive function in 272 seniors from high-fluoride regions and 172 from normal-fluoride regions, while measuring blood fluoride levels, oxidative-stress markers, APOE genotype, and DKK1 mRNA expression.
Older adults in high-fluoride areas had higher blood fluoride, higher DKK1 expression, and a greater rate of cognitive impairment compared with those in normal-fluoride areas. They also showed lower SOD antioxidant levels, indicating increased oxidative stress, though MDA and GSH did not differ. Several lifestyle and health factors varied between groups, but DKK1 levels remained positively correlated with cognitive decline. Statistical analysis identified DKK1 as one of the key risk factors for impaired cognition in high-fluoride regions.
Overall, the findings suggest that elevated fluoride exposure may contribute to cognitive impairment in older adults, potentially through pathways involving DKK1 and oxidative stress.
PMID: 34886821
PMCID: PMC8656079
DOI: 10.1186/s12889-021-12310-6
Abstract
Objective
To evaluate cognitive impairment and risk factors of elders in high fluoride drinking water areas and investigate whether DKK1 is involved in this disorder.
Methods
MoCA-B and AD-8 were used to measure the cognitive functions of 272 and 172 subjects over the age of 60 came from the high and normal fluoride drinking water areas respectively, general information and peripheral blood were collected, the level of SOD, GSH and MDA were measured, mRNA level of DKK1, the concentration of blood fluoride and the polymorphism of APOE were tested.
Results
The blood fluoride concentration, mRNA level of DKK1 and ratio of abnormal cognitive function of subjects in high fluorine drinking water areas were higher than those in normal areas. The level of SOD of subjects in high fluorine drinking water was low compared with those in normal areas. The level of MDA and GSH had no difference between the two crowds in different fluorine drinking water areas. There were differences in cigarette smoking, education, dental status, hypertension, hyperlipidaemia and APOE results between the two crowds in different fluorine drinking water areas. The mRNA level of DKK1 and the level of cognitive function showed a positive correlation and DKK1 was one of five risk factors involved in cognitive impairment of older people living in high fluorosis areas.
Conclusions
The cognitive functions could be impaired in the older people living in high fluoride drinking water areas, and DKK1 may as a potential intervention point of this brain damage process need attention.
Ren C, Zhang P, Yao XY, Li HH, Chen R, Zhang CY, Geng DQ. The cognitive impairment and risk factors of the older people living in high fluorosis areas: DKK1 need attention. BMC Public Health. 2021 Dec 9;21(1):2237. doi: 10.1186/s12889-021-12310-6. PMID: 34886821; PMCID: PMC8656079.