Physical health and depressive symptoms in older Europeans. Results from EURODEP.
Braam AW, et al.;
Commented by , 26 Jul 2005
Background
Poor physical health is a major risk factor for depression in later life : with bereavement and cognitive decline, it may distinguish depression in later life from earlier onset depression.
In under 65s, it is known from a world-wide study (ref. 1) that the association between disability and depression is consistent across cultures: this pan-European study sought to establish the relationship between disability and depression in older adults.
Aims
To examine cross-national differences in the association between physical health and depressive symptoms in older people across 11 countries in Western Europe.
Method
EURODEP is a consortium of 14 research groups from 11 European countries. Using pooled data, 22,570 subjects were included, with comparative demographic data on gender, age, marital status, and education.
Outcome Measures
- Depressive symptoms – were measured by the Euro-D Scale, which harmonises several other internationally used rating scales. The Euro-D Scale comprises depressive affect, pessimism, wishing death, guilt, sleep, interest, irritability, appetite, fatigue, concentration, enjoyment and tearfulness. Internal consistency using this scale across centres was high.
- Physical health – was recorded by functional disability (assessed by activities of daily living scales) and presence of chronic physical conditions, trichotomised into no, intermediate, or high levels of disability.
- Cognitive functioning – was assessed using the Mini Mental State Examination (MMSE) in 11/14 centres.
Statistics
Associations between physical health measures and depressive symptoms were analysed separately for each centre using linear regression analysis, adjusted for demographic effects. The data from different centres was pooled and examined using multilevel random regression modelling.
Results
There was substantial congruence between centres in the association between functional disability and depressive symptoms. The variance was higher in centres where instruments were used with a higher number of items on disability.
Analysing the data for three diseases only – cardiovascular disease, diabetes and stroke – which are commoner in the very old, produced a similar association.
Expressed as standardised co-efficients for the trichotomised scores, the strength of association between functional disability and depressive symptoms ranged between 0.16 and 0.37.
Discussion
This study tested the hypothesis that depression in older people may not be as strongly associated with disability as it is in younger people, as heterogeneity across cultures may arise from variations in the availability of health care and attitudes to old age.
On the contrary, the study found consistency between physical health variables and depressive symptoms in late life in 11 Western European countries, across North and South Europe.
Furthermore, functional disability had a stronger association with depressive symptoms than did individual chronic diseases.
The study has limitations in that the sampling procedures and use of outcome measures were not applied consistently across all centres. The oldest and most disabled people (who may be in hospital or nursing homes) were variably under-represented in the (community) samples.
The study focussed on depressive symptoms in the Euro-D Scale, rather than depression as a syndromal diagnosis, though the authors report similar associations between physical disability and depressive illness (defined by the Geriatric Mental State and DSM diagnosis) in those centres that used these criteria.
In summary, the relationship between physical decline and depression is likely to be universal as it is in younger people, and applies also to the oldest old : sociological and cultural factors give way to life cycle factors. The clinical implication is that concurrent assessment and management of disability is universally required in the treatment of depression.
Reference
Ormel J, et al. Common mental disorders and disability across cultures; results from the WHO collaborative study on psychological problems in general health care. JAMA 2004; 272; 1741-48.