Environmental risk factors for dementia are poorly understood. Aluminium and fluorine in drinking water have been linked with dementia but uncertainties remain about this relationship.
In the largest longitudinal study in this context, we set out to explore the individual effect of aluminium and fluoride in drinking water on dementia risk and, as fluorine can increase absorption of aluminium, we also examine any synergistic influence on dementia.
We used Cox models to investigate the association between mean aluminium and fluoride levels in drinking water at their residential location (collected 2005–2012 by the Drinking Water Quality Regulator for Scotland) with dementia in members of the Scottish Mental Survey 1932 cohort who were alive in 2005.
A total of 1972 out of 6990 individuals developed dementia by the linkage date in 2012. Dementia risk was raised with increasing mean aluminium levels in women (hazard ratio per s.d. increase 1.09, 95% CI 1.03–1.15, P < 0.001) and men (1.12, 95% CI 1.03–1.21, P = 0.004). A dose-response pattern of association was observed between mean fluoride levels and dementia in women (1.34, 95% CI 1.28–1.41, P < 0.001) and men (1.30, 95% CI 1.22–1.39, P < 0.001), with dementia risk more than doubled in the highest quartile compared with the lowest. There was no statistical interaction between aluminium and fluoride levels in relation with dementia.
Higher levels of aluminium and fluoride were related to dementia risk in a population of men and women who consumed relatively low drinking-water levels of both.
- Livingston, G, Sommerlad, A, Orgeta, V, Costafreda, SG, Huntley, J, Ames, D, et al. Dementia prevention, intervention, and care. Lancet; 390(10113): 2673–734. CrossRef | Google Scholar
- Russ, TC, Gatz, M, Pedersen, NL, Hannah, J, Wyper, G, Batty, GD, et al. Geographical variation in dementia: examining the role of environmental factors in Sweden and Scotland. Epidemiology 2015; 26(2): 263–70. CrossRef | Google Scholar | PubMed
- Mokry, LE, Ross, S, Morris, JA, Manousaki, D, Forgetta, V, Richards, JB. Genetically decreased vitamin D and risk of Alzheimer disease. Neurology 2016; 87(24): 2567–74. CrossRef | Google Scholar | PubMed
- Killin, LO, Starr, JM, Shiue, IJ, Russ, TC. Environmental risk factors for dementia: a systematic review. BMC Geriatr 2016; 16(1): 175. CrossRef | Google Scholar | PubMed
- Cacciottolo, M, Wang, X, Driscoll, I, Woodward, N, Saffari, A, Reyes, J, et al. Particulate air pollutants, APOE alleles and their contributions to cognitive impairment in older women and to amyloidogenesis in experimental models. Transl Psychiatry 2017; 7: e1022. CrossRef | Google Scholar | PubMed
- Scottish Water. Your Water Quality Explained. Scottish Water, 2015 (https://www.scottishwater.co.uk/assets/domestic/files/you%20and%20your%20home/water%20quality/swyourwaterquality2015.pdf). Google Scholar
- World Health Organization. Guidelines for Drinking-Water Quality (4th edn). World Health Organization, 2011. Google Scholar
- Kawahara, M, Kato-Negishi, M. Link between aluminum and the pathogenesis of Alzheimer’s disease: the integration of the aluminum and amyloid cascade hypotheses. Int J Alzheimer’s Dis 2011; 2011: 276393. Google Scholar | PubMed
- Rondeau, V, Jacqmin-Gadda, H, Commenges, D, Helmer, C, Dartigues, J-F. Aluminum and silica in drinking water and the risk of Alzheimer’s disease or cognitive decline: findings from 15-year follow-up of the PAQUID cohort. Am J Epidemiol 2008; 169(4): 489–96. CrossRef | Google Scholar | PubMed
- Lubkowska, A, Zyluk, B, Chlubeka, D. Interactions between fluorine and aluminum. Fluoride 2002; 35(2): 73–7. Google Scholar
- Deary, IJ, Whalley, LJ, Starr, JM. A Lifetime of Intelligence: Follow-Up Studies of the Scottish Mental Surveys of 1932 and 1947. American Psychological Association, 2009. CrossRef | Google Scholar
- World Health Organization. Manual of the International Classification of Diseases, Injuries, and Causes of Death, Ninth Revision (ICD-9). WHO, 1977. Google Scholar
- World Health Organization. The ICD-10 Classification of Mental and Behavioural Disorders: Clinical Descriptions and Diagnostic Guidelines. WHO, 1992. Google Scholar
- SIMD. 2012 Technical Notes. Scottish Government, 2012 (https://www2.gov.scot/Resource/0050/00504822.pdf). Google Scholar
- Doubal, FN, Ali, M, Batty, GD, Charidimou, A, Eriksdotter, M, Hofmann-Apitius, M, et al. Big data and data repurposing – using existing data to answer new questions in vascular dementia research. BMC Neurol 2017; 17(1): 72. CrossRef | Google Scholar | PubMed
- Russ, TC, Hannah, J, Batty, GD, Booth, CC, Deary, IJ, Starr, JM. Childhood cognitive ability and incident dementia: the 1932 Scottish Mental Survey Cohort into their 10th Decade. Epidemiology 2017; 28(3): 361–4. CrossRef | Google Scholar | PubMed
- Altmann, P, Cunningham, J, Dhanesha, U, Ballard, M, Thompson, J, Marsh, F. Disturbance of cerebral function in people exposed to drinking water contaminated with aluminium sulphate: retrospective study of the Camelford water incident. BMJ 1999; 319(7213): 807–11. CrossRef | Google Scholar | PubMed
- Still, CN, Kelley, P. On the incidence of primary degenerative dementia vs. water fluoride content in South Carolina. Neurotoxicology 1980; 1(4): 125–31. Google Scholar
- Verstraeten, SV, Aimo, L, Oteiza, PI. Aluminium and lead: molecular mechanisms of brain toxicity. Arch Toxicol 2008; 82(11): 789–802. CrossRef | Google Scholar | PubMed
- Matthews, FE, Arthur, A, Barnes, LE, Bond, J, Jagger, C, Robinson, L, et al. A two-decade comparison of prevalence of dementia in individuals aged 65 years and older from three geographical areas of England: results of the Cognitive Function and Ageing Study I and II. Lancet 2013; 382(9902): 1405–12. CrossRef | Google Scholar | PubMed
- Russ, TC, Batty, GD, Starr, JM. Cognitive and behavioural predictors of survival in Alzheimer disease: results from a sample of treated patients in a tertiary-referral memory clinic. Int J Geriatr Psychiatry 2012; 27(8): 844–53. CrossRef | Google Scholar
- Russ, TC, Parra, MA, Lim, AE, Law, E, Connelly, PJ, Starr, JM. Prediction of general hospital admission in people with dementia: cohort study. Br J Psychiatry 2015; 206(2): 153–9. CrossRef | Google Scholar | PubMed
- Sudlow, C, Gallacher, J, Allen, N, Beral, V, Burton, P, Danesh, J, et al. UK biobank: an open access resource for identifying the causes of a wide range of complex diseases of middle and old age. PLoS Med 2015; 12(3): e1001779. CrossRef | Google Scholar | PubMed
- Wu, Y-T, Fratiglioni, L, Matthews, FE, Lobo, A, Breteler, MM, Skoog, I, et al. Dementia in western Europe: epidemiological evidence and implications for policy making. Lancet Neurol 2016; 15(1): 116–24. CrossRef | Google Scholar | PubMed
- Bradford Hill, A. The environment and disease: association or causation? Proc R Soc Med 1965; 58: 295–300. Google Scholar
- Calvin, CM, Batty, GD, Der, G, Brett, CE, Taylor, A, Pattie, A, et al. Childhood intelligence in relation to major causes of death in 68 year follow-up: prospective population study. BMJ 2017; 357: j2708. CrossRef | Google Scholar | PubMed
- McGurn, B, Deary, IJ, Starr, JM. Childhood cognitive ability and risk of late-onset Alzheimer and vascular dementia. Neurology 2008; 71(14): 1051–6. CrossRef | Google Scholar | PubMed
- Whalley, LJ, Starr, JM, Athawes, R, Hunter, D, Pattie, A, Deary, IJ. Childhood mental ability and dementia. Neurology 2000; 55(10): 1455–9. CrossRef | Google Scholar | PubMed
- Duan, Q, Jiao, J, Chen, X, Wang, X. Association between water fluoride and the level of children’s intelligence: a dose–response meta-analysis. Public Health 2018; 154: 87–97. CrossRef | Google Scholar | PubMed
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