ReviewAge- and gender-specific prevalence of depression in latest-life – Systematic review and meta-analysis
Introduction
Depression is one of the most prevalent mental disorders in old age. Elderly individuals with clinically significant depressive symptoms are faced with a number of negative consequences including functional decline, marked disability, decreased quality of life, and higher mortality from comorbid medical conditions (Fiske et al., 2009). Furthermore, depression in elderly individuals is associated with an increase in health care costs (Luppa et al., 2008), and is most common in nursing home residents (Blazer, 2003).
Late-life depression may occur on a spectrum ranging from very mild “subthreshold” forms to major depression (Fiske et al., 2009, Lavretsky and Kumar, 2002, Riedel-Heller et al., 2006) differing only quantitatively regarding severity of symptoms. Moreover, it has been pointed out that the nature of depression experienced by younger and older individuals may differ qualitatively. The depression picture of elderly individuals is characterized by changes in a somatic and a psychological component (Christensen et al., 1999, Fiske et al., 2009), whereas sleep disturbance, loss of appetite, fatigue as well as hopelessness about the future, subjective memory complaints, and cognitive deficits are more prevalent symptoms in late-life depression than in depression in younger adults. Hence, diagnostics of late-life depression should take into account these disparities between adult and late-life depression. Currently, diagnostics of depression in elderly individuals is most often based on symptom rating scales or on the categorical classification system DSM-IV (Diagnostic and Statistical Manual for Mental disorders, fourth edition). It has been criticized that the diagnostic categories of DSM-IV were not specially-tailored for late-life depression, thus only suitable to a limited extent in old age groups. The rather low prevalence rates of major depression in elderly individuals compared to less severe variants of depressive disorders may support this assumption (Beekman et al., 1999).
Due to increasing life expectancies, one should keep in mind that the term “late life” now encompasses a heterogeneous group of individuals aged between 60 and over 100 years. Therefore, the research on late-life depression has addressed its diversity within late life (Chou and Chi, 2005, Mehta et al., 2008, Van Leeuwen et al., 2010). In order to assess future needs of the health care system for prevention and treatment, information on prevalence of depression among the oldest age groups is required. However, previous reviews only focused on prevalence rates of late life depression across the entire advanced age range (Beekman et al., 1999, Djernes, 2006). Thus, the objective of the present study is to systematically analyze the prevalence of depression in latest life (aged 75 years and older), particularly focusing on age- and gender-specific rates across the latest-life age groups.
Section snippets
Methods
We adhered to systematic literature review guidelines (Centre for Reviews and Dissemination, 2008). The review process occurred in three steps: obtaining, extracting and assessing data for this study.
Study characteristics
The results of the systematic literature search are shown in Fig. 1. Altogether, 334 potentially relevant articles were identified. 33 of these were found in reference lists of the identified articles. After perusing all full articles, 310 further articles were rejected as not fulfilling the selection criteria. Twenty-four studies were assessed and subjected to the detailed analysis. In the following, the results of studies were ordered and presented according to the type of diagnostics of
Discussion
In view of the demographic changes in developed countries, the number of elderly people, especially related to the old–old and the oldest–old age segment, will increase substantially in the coming decades. Thus, the relevance of understanding the clinical features of depression in the highest age groups, those 75 years and older, will become more relevant. The present study systematically reviewing the age- and gender-specific prevalence of depression in older age is a first step towards
Conclusions
Our findings show that depressive symptoms are frequent in latest life. From the viewpoint of the demographic change in developed countries, the number of individuals with latest-life depression will increase substantially. The results of this review re-emphasize the significance of precise diagnostics of depression in old age. Particularly, adequate sampling strategies (e.g. inclusion of nursing home residents and severe cognitively impaired individuals) will reduce methodical disparities and
Role of funding source
This publication is part of the German Research Network on Dementia (KND) and the German Research Network on Degenerative Dementia (KNDD) and was funded by the German Federal Ministry of Education and Research (grant KND: 01GI0431, grant KNDD: 01GI0714); 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.
Conflict of interest
All authors declare that they have no conflict of interest.
Acknowledgement
None.
References (53)
- et al.
Prevalence and risk factors for depression in a longitudinal, population-based study including individuals in the community and residential care
Am. J. Geriatr. Psychiatry
(2007) - et al.
Comorbid depression and anxiety in later life: patterns of association, subjective well-being, and impairment
Am. J. Geriatr. Psychiatry
(2008) - et al.
Meta-analysis in clinical trails
Control. Clin. Trials
(1986) - et al.
Epidemiology of major depressive disorder in elderly Nigerians in the Ibadan Study of Ageing: a community-based survey
Lancet
(2007) - et al.
Prevalence and risk indicators of depression in elderly nursing home patients: the AGED study
J. Affect. Disord.
(2004) - et al.
Clinically significant non-major depression: old concepts, new insights
Am. J. Geriatr. Psychiatry
(2002) - et al.
Direct costs associated with depression in old age in Germany
J. Affect. Disord.
(2008) - et al.
The Patient Health Questionnaire 8: current depressive symptoms among U.S. older adults, 2006 Behavioral Risk Factor Surveillance System
Am. J. Geriatr. Psychiatry
(2009) - et al.
Quality of life among long-term breast cancer survivors: a systematic review
Eur. J. Cancer
(2005) - et al.
Association between depression and socio-economic status among community-dwelling elderly in Japan: the Aichi Gerontological Evaluation Study (AGES)
Health Place
(2008)