Alcohol consumption and risk of dementia: 23 year follow-up of Whitehall II cohort studyBMJ 2018; 362 doi: https://doi.org/10.1136/bmj.k2927 (Published 01 August 2018) Cite this as: BMJ 2018;362:k2927
- Séverine Sabia, research associate12,
- Aurore Fayosse, statistician1,
- Julien Dumurgier, associate professor3,
- Aline Dugravot, statistician1,
- Tasnime Akbaraly, research associate245,
- Annie Britton, professor2,
- Mika Kivimäki, professor2,
- Archana Singh-Manoux, research professor12
- 1Inserm, U1018, Centre for Research in Epidemiology and Population Health, Université Paris-Saclay, France; Hôpital Paul Brousse, Bât 15/16, Villejuif Cedex, France
- 2Department of Epidemiology and Public Health, University College London, UK
- 3Cognitive Neurology Center, Lariboisière-Fernand Widal hospital, AP-HP, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
- 4Inserm U1198, Montpellier, France; University Montpellier, Montpellier, France; EPHE, Paris, France
- 5Department of Psychiatry & Autism Resources Centre, University Research and Hospital Center (CHRU) of Montpellier, Montpellier, France
- Correspondence to: S Sabia (or @epiageing on Twitter)
- Accepted 25 June 2018
Objective To examine the association between alcohol consumption and risk of dementia.
Design Prospective cohort study.
Setting Civil service departments in London (Whitehall II study).
Participants 9087 participants aged 35-55 years at study inception (1985/88).
Main outcome measures Incident dementia, identified through linkage to hospital, mental health services, and mortality registers until 2017. Measures of alcohol consumption were the mean from three assessments between 1985/88 and 1991/93 (midlife), categorised as abstinence, 1-14 units/week, and >14 units/week; 17 year trajectories of alcohol consumption based on five assessments of alcohol consumption between 1985/88 and 2002/04; CAGE questionnaire for alcohol dependence assessed in 1991/93; and hospital admission for alcohol related chronic diseases between 1991 and 2017.
Results 397 cases of dementia were recorded over a mean follow-up of 23 years. Abstinence in midlife was associated with a higher risk of dementia (hazard ratio 1.47, 95% confidence interval 1.15 to 1.89) compared with consumption of 1-14 units/week. Among those drinking >14 units/week, a 7 unit increase in alcohol consumption was associated with a 17% (95% confidence interval 4% to 32%) increase in risk of dementia. CAGE score >2 (hazard ratio 2.19, 1.29 to 3.71) and alcohol related hospital admission (4.28, 2.72 to 6.73) were also associated with an increased risk of dementia. Alcohol consumption trajectories from midlife to early old age showed long term abstinence (1.74, 1.31 to 2.30), decrease in consumption (1.55, 1.08 to 2.22), and long term consumption >14 units/week (1.40, 1.02 to 1.93) to be associated with a higher risk of dementia compared with long term consumption of 1-14 units/week. Analysis using multistate models suggested that the excess risk of dementia associated with abstinence in midlife was partly explained by cardiometabolic disease over the follow-up as the hazard ratio of dementia in abstainers without cardiometabolic disease was 1.33 (0.88 to 2.02) compared with 1.47 (1.15 to 1.89) in the entire population.
Conclusion The risk of dementia was increased in people who abstained from alcohol in midlife or consumed >14 units/week. In several countries, guidelines define thresholds for harmful alcohol consumption much higher than 14 units/week. The present findings encourage the downward revision of such guidelines to promote cognitive health at older ages.
Contributors: ASM and SS developed the hypothesis and study design. SS, AF, and AD performed the statistical analysis. SS wrote the first and successive drafts of the manuscript. All authors conceived and designed the study, analysed and interpreted the data, and drafted or critically revised the manuscript for important intellectual content, or, in addition, acquired data. ASM and MK obtained funding for the Whitehall II study. SS, AD, and ASM had full access to the data and take responsibility for the integrity of the data and the accuracy of the data analysis. SS is the guarantor. The corresponding author attests that all listed authors meet authorship criteria and that no others meeting the criteria have been omitted.
Funding: The Whitehall II study is supported by grants from the US National Institutes on Aging (R01AG013196; R01AG034454), UK Medical Research Council (MRC K013351; MR/R024227/1), and British Heart Foundation (RG/13/2/30098). SS and MK are supported by an EC Horizon 2020 (633666, LIFEPATH). MK is supported by NordForsk.
Competing interests: All authors have completed the ICMJE uniform disclosure form at http://www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare no other support from any organisation for the submitted work than the grants reported in the funding section; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years, no other relationships or activities that could appear to have influenced the submitted work. The sponsors had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of this manuscript.
Ethical approval: This study was approved by University College London Hospital Committee on the Ethics of Human Research (reference No 85/0938). Written informed consent from participants and research ethics approvals were renewed at each contact.
Data sharing: Data, protocols, and other metadata of the Whitehall II study are available to the scientific community. Please refer to the Whitehall II study data sharing policy at www.ucl.ac.uk/whitehallII/data-sharing.
Transparency: The lead author (SS) affirms that this manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned have been explained.
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