Elsevier

Neurobiology of Aging

Volume 32, Issue 7, July 2011, Pages 1336-1337
Neurobiology of Aging

Negative results
Atrial fibrillation, stroke and dementia in the very old: A population-based study

https://doi.org/10.1016/j.neurobiolaging.2009.08.002Get rights and content

Abstract

We explored the association of chronic AF with stroke, dementia and Alzheimer's disease (AD) among community-dwelling elderly people. The study population consisted of 685 individuals from Stockholm (The Kungsholmen Project) who were aged 78 years and were free of dementia and clinical stroke. During the 6-year follow-up, 170 subjects developed dementia, and 86 persons experienced first-ever stroke. The incidence rate (per 1000 person-years) of dementia, AD and first-ever stroke was 72.3, 52.2, and 52.2 in persons with AF and 63.8, 54.6 and 30.6 in those without AF, respectively. AF was associated with the hazard ratio of 1.8 (95%CI, 1.0–3.4) for first-ever stroke, but not significantly associated with dementia or AD.

Introduction

Atrial fibrillation (AF) and dementia are two very common diseases in the elderly that substantially contribute to morbidity and mortality. The main hazard related to AF is embolic stroke, which accounts for the majority of brain vascular lesions in advanced age. Furthermore, persons with AF are more likely to develop not only symptomatic stroke, but also silent cerebral infarctions and white matter lesions, which have been associated with cognitive impairment. However, evidence of a causal relationship between AF and dementia, and in particular Alzheimer's disease (AD), is limited (Lip and Lim, 2007). In this study, we sought to examine the longitudinal association of chronic AF with stroke, dementia and AD using the 6-year follow-up data from a community cohort of very old people.

Section snippets

Methods

The study population was derived from the Kungsholmen Project (1987–2000), a community-based study designed to evaluate risk factors for dementia in Swedish older persons (Fratiglioni et al., 1992). All registered inhabitants living in the Kungsholmen district of Stockholm, Sweden, and 75 years and older in October 1987 (n = 2368), were invited to participate in the project. The dementia- and stroke-free cohort identified at the first follow-up of the project (1991–1993) (n = 685) was re-examined

Results

During the 3058 person-years of follow-up (mean 4.0 years per person), 170 subjects were diagnosed with dementia, including 143 AD cases, and 86 subjects were diagnosed as having first-ever stroke. The IR (per 1000 person-years) of dementia, AD and first-ever stroke was 72.3, 52.2, and 52.2 in persons with AF and 63.8, 54.6 and 30.6 in those without AF, respectively. Multiadjusted Cox regression models suggested that AF was significantly associated with the HR of first-ever stroke, but neither

Discussion

In this follow-up study of a large-scale community cohort of very old adults, we confirmed an association of AF with first-ever stroke. However, neither dementia nor AD was associated with AF either in the whole cohort or in any strata identified by sociodemographic characteristics, use of antithrombotic treatments, and APOE genotype. These findings may have implications for primary prevention of stroke in very old people as well as for future studies evaluating the vascular hypothesis of AD.

Conflict of interest

The authors do not have any potential conflicts of interest.

Acknowledgements

This study was supported by grants from the Swedish Council for Working Life and Social Research and the Swedish Research Council. The funding sources had no role in the study design, data analysis, or report writing.

References (2)

Cited by (58)

  • Relation of Atrial Fibrillation to Cognitive Decline (from the REasons for Geographic and Racial Differences in Stroke [REGARDS] Study)

    2021, American Journal of Cardiology
    Citation Excerpt :

    Several longitudinal studies have shown that individuals with AF experience higher rates of cognitive decline.1,4,10,22 However, other reports suggest that AF does not increase the risk of cognitive decline.23,24 Further, findings from the population-based Kungsholmen Project suggest that AF was not significantly associated with dementia or AD.23

  • Atrial Fibrillation and Cognitive Impairment: New Insights and Future Directions

    2020, Heart Lung and Circulation
    Citation Excerpt :

    Based on these investigations, the relationship between AF and cognitive function was evaluated in different underlying conditions including CHF [28] and hypertension [32]. Less than half of the studies also reported no important differences between AF patients and controls in terms of cognitive function either at baseline [26,27] or during the follow-up period (12 months to 9 years) [26,27,30,32]. On the other hand, a positive relationship was observed in all other studies on a cumulative sample size of more than 40,000 individuals (almost nine times greater than the sample size of studies reporting no significant relationship) [12,24,25,28,29,33,34].

View all citing articles on Scopus
View full text