Is the relationship between syndromes of depression and dementia temporal? The MRC-ALPHA and Hefei-China studies

Psychol Med. 2009 Mar;39(3):425-30. doi: 10.1017/S0033291708003735. Epub 2008 Jun 23.


Background: Recent studies have shown a temporal association between depressive symptoms and cognitive decline. However, the relationship between syndromes of depression and dementia is unknown.

Method: A total of 1736 people aged > or = 65 years in China and 5222 older people in the UK were interviewed using the Geriatric Mental State Examination (GMS) and reinterviewed at follow-up. Five levels of syndromes of depression and dementia were diagnosed using the Automated Geriatric Examination for Computer Assisted Taxonomy (AGECAT).

Results: Although there were fewer depressive syndromes in Chinese than British participants, both populations showed a similarly high level of syndromes of dementia (organic disorder) (20% for women, 14% for men). There was a significant cross-sectional correlation between syndrome levels of depression and dementia (correlation coefficients: 0.141-0.248 for Chinese, 0.168-0.248 for British). This was maintained for different age, gender and people with and without cardiovascular disease (CVD). The relationship between syndromes of baseline depression and follow-up dementia was less substantial: the correlation coefficient was 0.075 [95% confidence interval (CI) 0.021-0.128] for the Chinese sample at the 1-year follow-up, and 0.093 (95% CI 0.061-0.125) for the British at the 2-year follow-up and 0.093 (95% CI 0.049-0.130) at the 4-year follow-up. This relationship disappeared in participants without baseline organic syndromes. In a multiple adjusted logistic regression analysis, an increased risk of organic syndromes seemed to be associated with baseline, mainly in the highest level of, depressive syndromes.

Conclusions: The relationship between syndromes of depression and dementia might be temporal. The lack of an obvious dose-response relationship between baseline depressive syndromes and follow-up dementia syndromes suggests that the causal relationship between depression and dementia needs further investigation.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Aged
  • China / epidemiology
  • Cognition Disorders / diagnosis
  • Cognition Disorders / epidemiology
  • Comorbidity
  • Cross-Cultural Comparison
  • Cross-Sectional Studies
  • Dementia / diagnosis
  • Dementia / epidemiology*
  • Depressive Disorder / diagnosis
  • Depressive Disorder / epidemiology
  • Female
  • Follow-Up Studies
  • Geriatric Assessment
  • Health Surveys
  • Humans
  • Male
  • Prevalence
  • Psychiatric Status Rating Scales / statistics & numerical data
  • Risk Factors
  • Severity of Illness Index
  • Sex Factors
  • Syndrome
  • United Kingdom / epidemiology