Risk factors for depressive disorders in very old age: a population-based cohort study with a 5-year follow-up.

PURPOSE: Depressive disorders are common among the very old, but insufficiently studied. The present study aims to identify risk factors for depressive disorders in very old age. METHODS: The present study is based on the GERDA project, a population-based cohort study of people aged ≥85 years (n = 567), with 5 years between baseline and follow-up. Factors associated with the development of depressive disorders according to DSM-IV criteria at follow-up were analysed by means of a multivariate logistic regression. RESULTS: At baseline, depressive disorders were present in 32.3 % of the participants. At follow-up, 69 % of those with baseline depressive disorders had died. Of the 49 survivors, 38 still had depressive disorders. Of the participants without depressive disorders at baseline, 25.5 % had developed depressive disorders at follow-up. Baseline factors independently associated with new cases of depressive disorders after 5 years were hypertension, a history of stroke and 15-item Geriatric Depression Scale score at baseline. CONCLUSIONS: The present study supports the earlier findings that depressive disorders among the very old are common, chronic and malignant. Mild depressive symptoms as indicated by GDS-15 score and history of stroke or hypertension seem to be important risk factors for incident depressive disorders in very old age.

Thirty-day prevalence of delirium among very old people: a population-based study of very old people living at home and in institutions.

Delirium has mainly been studied in various patient samples and in people living in institutions. The present study investigates the 30-day prevalence of delirium in a population-based sample of very old people in northern Sweden and Finland. Seven hundred and eight persons aged 85 years and older from the GErontological Regional DAtabase (GERDA) were assessed. Information was also collected from relatives, carers and medical records. Assessments performed were among others the Organic Brain Syndrome (OBS) scale, the Mini Mental State Examination (MMSE), and the Geriatric Depression Scale-15 (GDS-15). Delirium, depression and dementia diagnoses were based on the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) criteria. The prevalence of delirium was 17% among 85 year-olds, 21% among 90 year-olds and 39% among participants aged 95 years and older (p<0.001). Delirium prevalence among individuals without dementia was lower than among those with dementia (5% vs. 52%, p<0.001). Factors independently associated with delirium superimposed on dementia in a multivariate logistic regression model were depression (Odds Ratio (OR)=2.0, 95% Confidence Interval (CI)=1.2-3.3), heart failure (OR=2.1, 95% CI=1.2-3.7), institutional living (OR 4.4, 95% CI=2.4-8.2) and prescribed antipsychotics (OR=3.0, 95% CI=1.5-6.0). Delirium is highly prevalent among very old people with dementia. Depression, heart failure, institutional living and prescribed antipsychotic medication seem to be associated with delirium.

Increasing prevalence of dementia among very old people.

BACKGROUND: it is unknown whether the age-specific prevalence of dementia among the very old changes over time. METHODS: this study compares the prevalence of dementia in two population-based cross-sectional samples of very old people in northern Sweden in 2000-02 and in 2005-07. In total, 430 individuals aged 85 and older (mean age 89.5 years, 71.4% women) were evaluated for dementia in the first cross-section and 465 individuals (mean age 90.2 years, 70.9% women) in the second. Trained assessors performed assessments and interviews during home visits and collected information from carers, relatives and medical records. Dementia was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition criteria. RESULTS: the prevalence of dementia in the total sample was 26.5% in 2000-02 and 37.2% in 2005-07 (P = 0.001). There was also an increase in the prescription of different antihypertensive agents, antilipemic agents and choline esterase inhibitors, and more people had had heart surgery in the later sample. CONCLUSIONS: in this sample of very old people, an increase in the age-specific prevalence of dementia was detected over 5 years. Possible reasons for this may be extended survival among individuals with risk factors for dementia and among individuals with established dementia.