Impact of Impairment in Instrumental Activities of Daily Living and Mild Cognitive Impairment on Time to Incident Dementia – Results of the Leipzig Longitudinal Study of the Aged (LEILA75+)
Claudia Sikorski,
Melanie Luppa, Tobias Luck, Steffi G. Riedel-Heller
Institut für Sozialmedizin, Arbeitsmedizin und Public Health (ISAP),
Arbeitsgruppe Public Health: Epidemiologie und Versorgungsforschung
Universität Leipzig
Matthias
C. Angermeyer
Center for Public Mental Health, Gösing a. W., Austria & Department
of Public Health, University of Cagliary, Italy
Arno Villringer
Max-Planck-Institut
für Kognitions- und Neurowissenschaften und Tagesklinik für kognitive
Neurologie; Leipzig
Hans-Helmut König
Universitätsklinikum Hamburg-Eppendorf,
Zentrum für Psychosoziale Medizin, Institut für Medizinische Soziologie,
Sozialmedizin und Gesundheitsökonomie; Hamburg
1 . Zielsetzung/Fragestellung
Early diagnosis of dementia requires knowledge about associated predictors.
The aim of this study was to determine the impact of mild cognitive impairment
(MCI) and impairment in instrumental activities of daily living (IADL) on the
time to an incident dementia diagnosis.
2. Materialien/Methoden
Data were derived from the Leipzig Longitudinal Study of the Aged (LEILA75+),
a population-based study of individuals aged 75 years and older. Kaplan-Meier
survival analysis was used to determine time to incident dementia. Cox proportional
hazards models were applied to determine the impact of MCI and impairment in
IADL on the time to incident dementia.
3. Ergebnisse
180 (22.0%) of 819 initially dementia-free subjects developed dementia by the
end of the study. Mean time to incident dementia was 6.7 years (95% CI = 6.5-6.9).
MCI combined with impairment in IADL was associated with a higher conversion
rate to dementia and a shorter time to clinically manifest diagnosis. The highest
risk for a shorter time to incident dementia was found for amnestic MCI combined
with impairment in IADL: the mean time to incident dementia was 3.7 years (95%
CI = 2.9-4.4) and thus half as long as in subjects without MCI and impairment
in IADL.
4. Zusammenfassung/Schlussfolgerung
Subjects with MCI and impairment in IADL constitute a high-risk population
for the development of dementia. The consideration of impairment in IADL should
constitute an important step towards an MCI concept being clinically more useful
for prediction of dementia.
This publication was funded by the
junior research grant by the Medical Faculty, University of Leipzig. The
field work was supported by the Interdisciplinary
Centre for Clinical Research Leipzig (project C07) and published with affiliation
of the Leipzig Research Center for Civilization Diseases (LIFE, Universität
Leipzig). LIFE is financed by means of the European Union, by the European
Regional Development Fund (ERDF) and by means of the Free State of Saxony within
the framework of the excellence initiative.