Depression and incident dementia. An 8-year population-based prospective study

PLoS One. 2013;8(3):e59246. doi: 10.1371/journal.pone.0059246. Epub 2013 Mar 19.

Abstract

Aims: The aim of the study was to investigate the impact of depression (categorical diagnosis; major depression, MD) and depressive symptoms (dimensional diagnosis and symptom patterns) on incident dementia in the German general population.

Methods: Within the Leipzig Longitudinal Study of the Aged (LEILA 75+), a representative sample of 1,265 individuals aged 75 years and older were interviewed every 1.5 years over 8 years (mean observation time 4.3 years; mean number of visits 4.2). Cox proportional hazards and binary logistic regressions were used to estimate the effect of baseline depression and depressive symptoms on incident dementia.

Results: The incidence of dementia was 48 per 1,000 person-years (95% confidence interval (CI) 45-51). Depressive symptoms (Hazard ratio HR 1.03, 95% CI 1.01-1.05), and in particular mood-related symptoms (HR 1.08, 95% CI 1.03-1.14), showed a significant impact on the incidence of dementia only in univariate analysis, but not after adjustment for cognitive and functional impairment. MD showed only a significant impact on incidence of dementia in Cox proportional hazards regression, but not in binary logistic regression models.

Discussion: The present study using different diagnostic measures of depression on future dementia found no clear significant associations of depression and incident dementia. Further in-depth investigation would help to understand the nature of depression in the context of incident dementia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Dementia / diagnosis
  • Dementia / epidemiology*
  • Dementia / etiology*
  • Depression / complications*
  • Depression / diagnosis
  • Depression / epidemiology
  • Depressive Disorder, Major / complications*
  • Depressive Disorder, Major / diagnosis
  • Depressive Disorder, Major / epidemiology
  • Germany / epidemiology
  • Humans
  • Incidence
  • Interviews as Topic
  • Kaplan-Meier Estimate
  • Logistic Models
  • Longitudinal Studies
  • Proportional Hazards Models
  • Prospective Studies

Grants and funding

This work is published in affiliation with LIFE – Leipzig Research Center for Civilization Diseases, Universität Leipzig, and the Study on Late-Life Depression in Primary Care (AgeMooDe study, grant: 01GY1155A). LIFE is funded 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. Role of funding source: The field work was funded by the Interdisciplinary Centre for Clinical Research Leipzig (Project C07). The funding body had no further role in study design; in the collection, analysis and interpretation of data; in writing of the report; and the decision to submit the paper for publication. Tobias Luck was supported by a research fellowship of the German Research Foundation (grant: Lu 1730/1–1).