Exposure to air pollution and incident dementia and modification by APOE gene in the UK Biobank

Background: Brain iron deposition occurs in dementia. In European ancestry populations, the HFE p.C282Y variant can cause iron overload and hemochromatosis, mostly in homozygous males. Objective: To estimated p.C282Y associations with brain MRI features plus incident dementia diagnoses during follow-up in a large community cohort. Methods: UK Biobank participants with follow-up hospitalization records (mean 10.5 years). MRI in 206 p.C282Y homozygotes versus 23,349 without variants, including T2 * measures (lower values indicating more iron). Results: European ancestry participants included 2,890 p.C282Y homozygotes. Male p.C282Y homozygotes had lower T2 * measures in areas including the putamen, thalamus, and hippocampus, compared to no HFE mutations. Incident dementia was more common in p.C282Y homozygous men (Hazard Ratio HR = 1.83; 95% CI 1.23 to 2.72, p = 0.003), as was delirium. There were no associations in homozygote women or in heterozygotes. Conclusion: Studies are needed of whether early iron reduction prevents or slows related brain pathologies in male HFE p.C282Y homozygotes.

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Is Environmental and Occupational Particulate Air Pollution Exposure Related to Type-2 Diabetes and Dementia? A Cross-Sectional Analysis of the UK Biobank

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17249581 ◽

2020 ◽

Vol 17 (24) ◽

pp. 9581

Author(s):

Eirini Dimakakou ◽

Helinor J. Johnston ◽

George Streftaris ◽

John W. Cherrie

Keyword(s):

Air Pollution ◽

Occupational Exposure ◽

Environmental Exposure ◽

Uk Biobank ◽

Job Exposure Matrix ◽

Cross Sectional ◽

Particulate Air Pollution ◽

The Uk ◽

Sectional Analysis

Human exposure to particulate air pollution (e.g., PM2.5) can lead to adverse health effects, with compelling evidence that it can increase morbidity and mortality from respiratory and cardiovascular disease. More recently, there has also been evidence that long-term environmental exposure to particulate air pollution is associated with type-2 diabetes mellitus (T2DM) and dementia. There are many occupations that may expose workers to airborne particles and that some exposures in the workplace are very similar to environmental particulate pollution. We conducted a cross-sectional analysis of the UK Biobank cohort to verify the association between environmental particulate air pollution (PM2.5) exposure and T2DM and dementia, and to investigate if occupational exposure to particulates that are similar to those found in environmental air pollution could increase the odds of developing these diseases. The UK Biobank dataset comprises of over 500,000 participants from all over the UK. Environmental exposure variables were used from the UK Biobank. To estimate occupational exposure both the UK Biobank’s data and information from a job exposure matrix, specifically developed for UK Biobank (Airborne Chemical Exposure–Job Exposure Matrix (ACE JEM)), were used. The outcome measures were participants with T2DM and dementia. In appropriately adjusted models, environmental exposure to PM2.5 was associated with an odds ratio (OR) of 1.02 (95% CI 1.00 to 1.03) per unit exposure for developing T2DM, while PM2.5 was associated with an odds ratio of 1.06 (95% CI 0.96 to 1.16) per unit exposure for developing dementia. These environmental results align with existing findings in the published literature. Five occupational exposures (dust, fumes, diesel, mineral, and biological dust in the most recent job estimated with the ACE JEM) were investigated and the risks for most exposures for T2DM and for all the exposures for dementia were not significantly increased in the adjusted models. This was confirmed in a subgroup of participants where a full occupational history was available allowed an estimate of workplace exposures. However, when not adjusting for gender, some of the associations become significant, which suggests that there might be a bias between the occupational assessments for men and women. The results of the present study do not provide clear evidence of an association between occupational exposure to particulate matter and T2DM or dementia.

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Associations of ophthalmic and systemic conditions with incident dementia in the UK Biobank

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2021-319508 ◽

2021 ◽

pp. bjophthalmol-2021-319508

Author(s):

Xianwen Shang ◽

Zhuoting Zhu ◽

Yu Huang ◽

Xueli Zhang ◽

Wei Wang ◽

...

Keyword(s):

Heart Disease ◽

Age Related Macular Degeneration ◽

Hospital Inpatient ◽

Uk Biobank ◽

Age Related ◽

Incident Dementia ◽

Increased Risk ◽

The Uk ◽

Systemic Condition

AimsTo examine independent and interactive associations of ophthalmic and systemic conditions with incident dementia.MethodsOur analysis included 12 364 adults aged 55–73 years from the UK Biobank cohort. Participants were assessed between 2006 and 2010 at baseline and were followed up until the early of 2021. Incident dementia was ascertained using hospital inpatient, death records and self-reported data.ResultsOver 1 263 513 person-years of follow-up, 2304 cases of incident dementia were documented. The multivariable-adjusted HRs (95% CI) for dementia associated with age-related macular degeneration (AMD), cataract, diabetes-related eye disease (DRED) and glaucoma at baseline were 1.26 (1.05 to 1.52), 1.11 (1.00 to 1.24), 1.61 (1.30 to 2.00) and (1.07 (0.92 to 1.25), respectively. Diabetes, heart disease, stroke and depression at baseline were all associated with an increased risk of dementia. Of the combination of AMD and a systemic condition, AMD-diabetes was associated with the highest risk for incident dementia (HR (95% CI): 2.73 (1.79 to 4.17)). Individuals with cataract and a systemic condition were 1.19–2.29 times more likely to develop dementia compared with those without cataract and systemic conditions. The corresponding number for DRED and a systemic condition was 1.50–3.24. Diabetes, hypertension, heart disease, depression and stroke newly identified during follow-up mediated the association between cataract and incident dementia as well as the association between DRED and incident dementia.ConclusionsAMD, cataract and DRED but not glaucoma are associated with an increased risk of dementia. Individuals with both ophthalmic and systemic conditions are at higher risk of dementia compared with those with an ophthalmic or systemic condition only.

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Associations of air pollution with obesity and body fat percentage, and modification by polygenic risk score for BMI in the UK Biobank

Environmental Research ◽

10.1016/j.envres.2020.109364 ◽

2020 ◽

Vol 185 ◽

pp. 109364 ◽

Cited By ~ 1

Author(s):

Melissa A. Furlong ◽

Yann C. Klimentidis

Keyword(s):

Air Pollution ◽

Body Fat ◽

Risk Score ◽

Polygenic Risk Score ◽

Body Fat Percentage ◽

Uk Biobank ◽

Fat Percentage ◽

Polygenic Risk ◽

The Uk

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Predicting incident dementia 3-8 years after brief cognitive tests in the UK Biobank prospective study of 500,000 people

Alzheimer s & Dementia ◽

10.1016/j.jalz.2019.07.014 ◽

2019 ◽

Vol 15 (12) ◽

pp. 1546-1557 ◽

Cited By ~ 1

Author(s):

Catherine M. Calvin ◽

Tim Wilkinson ◽

John M. Starr ◽

Cathie Sudlow ◽

Saskia P. Hagenaars ◽

...

Keyword(s):

Prospective Study ◽

Cognitive Tests ◽

Uk Biobank ◽

Incident Dementia ◽

The Uk

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Visual Impairment and Risk of Dementia: the UK Biobank Study

10.1101/2021.01.08.21249188 ◽

2021 ◽

Author(s):

Zhuoting Zhu ◽

Danli Shi ◽

Huan Liao ◽

Jason Ha ◽

Xianwen Shang ◽

...

Keyword(s):

Visual Acuity ◽

Visual Impairment ◽

Visually Impaired ◽

Hospital Inpatient ◽

List Type ◽

Uk Biobank ◽

Clear Trend ◽

Incident Dementia ◽

The Uk ◽

The Relationship

ABSTRACTINTRODUCTIONThe association between visual impairment (VI) and the risk of dementia has been poorly understood. We sought to investigate the VI-dementia relationship in the UK Biobank Study.METHODSA total of 117,187 volunteers (aged 40-69 years) deemed free of dementia at baseline were included. Habitual distance visual acuity worse than 0.3 logMAR units in the better-seeing eye was used to define VI. The incident dementia was based on electronically linked hospital inpatient and death records.RESULTSDuring a median follow up of 5.96 years, the presence of VI was significantly associated with incident dementia (HR=1.78, 95% CI: 1.18-2.68, P=0.006). There was a clear trend between the severity of VI and the risk of dementia (P for trend=0.002).DISCUSSIONVisually impaired individuals were more likely to develop incident dementia, with a progressively greater risk among those with worse visual acuity. Our findings highlight the value of regular vision screening and elimination of VI.HIGHLIGHTSThe association between VI and dementia has been poorly understood;VI is associated with incident dementia in non-demented adults;There is a clear trend between the severity of VI and the risk of dementia;VI may be a marker of increased dementia risk.RESEARCH IN CONTEXTSYSTEMATIC REVIEWWe searched and reviewed the literature using traditional sources (e.g., PubMed and GoogleScholar). While the association between VI and cognitive function/decline are increasingly studies, investigation of the association between VI and the risk of dementia has been largely overlooked.INTERPRETATIONWe found that visually impaired individuals were more likely to develop incident dementia, with a progressively greater risk among those with worse visual acuity. Our findings imply that VI may be an important marker of dementia.FUTURE DIRECTIONSThese findings call for more studies to investigate (a) the role of visual acuity changes on the risk of dementia; (b) the relationship between other components of visual function and incident dementia; (c) the relationship between eye diseases and incident dementia; and (d) the potential benefits of vision rehabilitation on dementia prevention.

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