TY - JOUR

T1 - Dementia increases mortality beyond effects of comorbid conditions

T2 - A national registry-based cohort study

AU - Taudorf, Lærke

AU - Nørgaard, Ane

AU - Brodaty, Henry

AU - Laursen, Thomas Munk

AU - Waldemar, Gunhild

N1 - Publisher Copyright: © 2021 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.

PY - 2021

Y1 - 2021

N2 - Background and purpose: Mortality is known to be markedly increased in people with dementia. However, the association between multiple chronic conditions and mortality in dementia is not well clarified. The aim of this study was to investigate the impact of somatic and psychiatric diseases on mortality in dementia compared with the general elderly population. Methods: Using a cohort study design, nationwide registry data from 2006 to 2015 on dementia and psychiatric and somatic comorbidities defined by the Charlson Comorbidity Index (CCI) were linked. Impact of chronic conditions was assessed according to mortality rate ratios (MRRs) in all Danish residents aged ≥65 years with and without dementia. Results: Our population comprised 1,518,917 people, of whom 114,109 people were registered with dementia. The MRRs was 2.70 (95% confidence interval 2.68, 2.72) in people with dementia after adjusting for sex, age, calendar year, and comorbidities. MRRs increased with higher CCI score, and when comparing people with a similar comorbidity load, MRRs were significantly higher for people with dementia. Conclusions: The comorbidity load was associated with increased mortality in both people with and without dementia. Mortality in dementia remained increased, even after adjusting for psychiatric and chronic somatic comorbidities. Our findings suggest that dementia disorders alone contribute to excess mortality, which may be further increased by comorbidities.

AB - Background and purpose: Mortality is known to be markedly increased in people with dementia. However, the association between multiple chronic conditions and mortality in dementia is not well clarified. The aim of this study was to investigate the impact of somatic and psychiatric diseases on mortality in dementia compared with the general elderly population. Methods: Using a cohort study design, nationwide registry data from 2006 to 2015 on dementia and psychiatric and somatic comorbidities defined by the Charlson Comorbidity Index (CCI) were linked. Impact of chronic conditions was assessed according to mortality rate ratios (MRRs) in all Danish residents aged ≥65 years with and without dementia. Results: Our population comprised 1,518,917 people, of whom 114,109 people were registered with dementia. The MRRs was 2.70 (95% confidence interval 2.68, 2.72) in people with dementia after adjusting for sex, age, calendar year, and comorbidities. MRRs increased with higher CCI score, and when comparing people with a similar comorbidity load, MRRs were significantly higher for people with dementia. Conclusions: The comorbidity load was associated with increased mortality in both people with and without dementia. Mortality in dementia remained increased, even after adjusting for psychiatric and chronic somatic comorbidities. Our findings suggest that dementia disorders alone contribute to excess mortality, which may be further increased by comorbidities.

KW - cohort study

KW - comorbidity

KW - dementia

KW - mortality

U2 - 10.1111/ene.14875

DO - 10.1111/ene.14875

M3 - Journal article

C2 - 33894084

AN - SCOPUS:85105732460

VL - 28

SP - 2174

EP - 2184

JO - European Journal of Neurology

JF - European Journal of Neurology

SN - 1351-5101

IS - 7

ER -