Background
Background
Depression is a highly prevalent mental disease in the general population [1]
[2] and has a strong age dependency. It is also often found as a co-morbid condition in patients with a wide range of somatic disorders (e. g. cardiovascular diseases, renal failure, chronic pain) [3]
[4]
[5]
[6]
[7]
[8] and in those with other mental disorders (e. g. schizophrenia, personality disorders, addiction) [9]
[10]
[11]
[12]
[13]. Given the high prevalence of depression in the community rather little is known about the relationship between depression, daily functioning and health care utilisation in non-hospitalised elderly in the general population. Since depression can be difficult to diagnose, affected individuals might contact health care providers for various somatic symptoms or complaints but remain undetected. Thus, increased use of medical care might be associated with undiagnosed depression. In a previous study a set of common risk factors for depression in community dwelling elderly people was identified during a 1 year follow-up [14]. Among them were two or more clinic visits in the past month, poor self-rated health, poor cognitive status and impaired activities of daily living (ADL). Aim of our study was the assessment of the prevalence of depressive symptoms and the evaluation of their influence on activities of daily living and health care utilisation in the MEMO-Study (Memory and Morbidity in Augsburg Elderly) in Southern Germany.
Methods
Methods
The MEMO-Study (Memory and Morbidity in Augsburg Elderly) was performed 1997/98 as a follow-up project of a subgroup of the 1989/90 WHO MONICA Survey S2, Germany (Monitoring Trends and Determinants in Cardiovascular Disease) [15]
[16] on the KORA platform (Cooperative Health Research in the Region of Augsburg) in collaboration with the Central Hospital Augsburg. MEMO examines cognitive function and cardiovascular risk factors for neurodegenerative diseases in an elderly population. The study was restricted to participants of the second MONICA survey, who were 65 years and older on 1 October 1997 and lived in the city of Augsburg. The overall response rate among those eligible was 60.6 % yielding a total of 385 participants. For the presented analysis five individuals had to be excluded due to incomplete data on the Centre for Epidemiologic Studies Depression (CES-D) scale. The study was approved by the ethics committee of the University of Muenster, Germany.
Measurements
During the interview, depressed mood was measured with the Center for Epidemiologic Studies Depression (CES-D) scale, a 20-item, self-report scale designed to measure depressive symptoms experienced during the previous week [17]. It has been shown to be a valid and reliable instrument in older populations [18]. To identify respondents with a level of depressive symptomatology that is clinically relevant, the commonly used CES-D cut-off-score of 16 was applied. It has a good criterion validity for major depression [18].
Visits of study participants to a general practitioner (GP) or a specialist of any medical discipline in the 4 weeks before the interview were documented. Restrictions of activities of daily living (ADL) and instrumental activities of daily living (IADL) were assessed with an 18-item questionnaire [19]. The first group of ADLs comprised 10 different simple activities (e. g. washing, cleaning, meals, dressing etc.) and the second group (IADL) included 8 more complex activities (e. g. finances, shopping, writing, doctor visits etc). Answers to this questionnaire were subsequently dichotomized to help needed in one or more activities versus no helped needed in ADL and in IADL.
Results
Results
Three-hundred-eighty participants were included in this analysis, 53.2 % of them being males. Their mean age was 72.5 years. In Table [1] mean values of the CES-D scale are shown according to age, gender and number of co-morbidities. Higher age, female gender and having more than one co-morbid disorder were related to higher CES-D-scores. The overall 7-day-prevalence of clinical relevant depressive mood was 10.4 % (n = 40), with a variation by gender of 7.4 % (n = 15) among men and 14 % (n = 25) in women (Pearson’s Chi2 test p < 0.05).
Table 1 Centre of Epidemiologic Studies Depression Scale (CES-D): Scores according to age, gender and co-morbidity in 380 participants of the MEMO-Study Augsburg 1997/98, a follow-up study of a subsample of participants from the MONICA survey S2 (1989/90)
| n | CES-D (mean, SD) |
| overall | 380 | 8.4 (6.8) |
| age group | 65 - 69 years
70 - 75 years
75 + years | 104
134
141 | 7.7 (6.1)
8.0 (6.1)
9.2 (7.8) |
| gender | female
male | 178
202 | 9.9 (7.2)
7.0 (6.1) |
| co-morbidities[1]
| 0 - 1
2 - 3
4 + | 205
149
19 | 7.6 (6.2)
9.3 (7.6)
9.3 (4.9) |
|
1any of the following diseases: stroke, myocardial infarction, cardiac arrhythmia, heart failure, hypertension, Parkinsonism, hypo-/hyperthyroidism, diabetes, operation/amputation of limbs with/without prothesis
|
Table [2] shows percentages of participants with clinically relevant depressive mood in relation to sociodemographic factors, health care utilisation and activities of daily living. Higher proportions of depressed participants were found among women and in the two higher age groups. No significant differences between depressed and non-depressed study participants were observed for the two major disease groups of cardiovascular morbidity and co-morbid conditions related to diseases of the bones and/or joints. Summarizing the number of co-morbidities instead did not yield a significant difference either. Participants suspicious for manifest depression had higher probabilities of health care utilisation during the preceeding 4 weeks (outpatient contacts and hospital admissions). The largest difference was observed for general practitioner contacts yielding a 3-fold higher probability for those with depressed mood. Specialist visits during the preceeding 4 weeks and hospital admissions during the last 12 months did not reach statistical significance despite being higher among those with depression. High percentages of participants in the latter group reported impairments either in simple activities of daily living or in more complex instrumental activities. Compared to those with no depressed mood participants with depression had a 3-fold higher chance to be restricted in at least one item of the basic activities and even a 4-fold chance to be limited in one or more of the eight instrumental activities.
Table 2 Depressive mood according to sociodemographic factors, co-morbidities, health care utilization and activities of daily living in 380 participants of the MEMO-Study Augsburg
| | no depressed mood
(CES-D score < 16)
(n = 340) | depressed mood
(CES-D score[*] ≥ 16)
(n = 40) | odds ratio[1]
95 % CI |
| age group[2] % |
| 65 - 69 y
70 - 75 y
75 + y
trend
| 28.8
34.7
36.5 | 17.5
40.0
42.5 | 1.00
1.94
2.09
1.38
|
reference
0.76 - 4.93
0.83 - 5.28
0.90 - 2.12
|
| female gender[2], % | 45.0 | 62.5 | 2.12 | 1.08 - 4.19 |
| cardiovascular morbidity[3], % | 31.5 | 30.0 | 0.89 | 0.43 - 1.87 |
| morbidity of bones/ joints[4], % | 11.8 | 12.5 | 1.08 | 0.39 - 2.96 |
| co-morbidities[5], % |
| 0 - 1
2 - 3
4 + | 55.5
38.8
5.7 | 50.0
50.0
0.0 | 1.00
1.41
- |
reference
0.71 - 2.8
- |
| GP visit/4 weeks[6], % | 54.7 | 80.0 | 3.23 | 1.44 - 7.25 |
| specialist visit/4 weeks[6], % | 30.6 | 37.5 | 1.35 | 0.68 - 2.69 |
hospital treatment/
12 months[7], % | 21.1 | 27.5 | 1.44 | 0.68 - 3.06 |
| ADL restriction[8], % | 29.5 | 60.0 | 3.07 | 1.53 - 6.19 |
| IADL restriction[9], % | 36.6 | 70.0 | 4.02 | 1.93 - 8.39 |
|
1odds ratios derived from logistic regression models adjusted for age and gender
2adjusted only for gender or age, respectively
3any of the following cardiovascular diseases: hypertension, myocardial infarction, cardiac arrhythmia, heart failure
4any of the following disease of bones or joints: operation/ amputation of limbs with/without prothesis
5co-morbidities include the listed cardiovascular and bone/joint diseases plus Diabetes, hypo-/hyperthyroidism, parkinsonism
6visits to a general practitioner or specialist during the preceeding 4 weeks
7inpatient treatment during the preceeding 12 months
8ADL: restrictions in one or more ‘activities of daily living’ related to toilet, dressing, washing, bathing, do one’s hair/shaving, getting out of bed, cutting food, having meals, walking in flat, intake of medication
9IADL: restrictions in one or more ‘instrumental activities of daily living’ related to finances/budget, doing shopping, writing letters, serving visitors, cleaning flat, do the washing, phoning, visits to GP/pharmacist/physiotherapist
|
Discussion
Discussion
In this study of an elderly, general population we found a prevalence of 10.4 % individuals with depressive symptoms severe enough to be suspicious for clinical manifest depression. Women were twice as often affected as men which is a common finding in community studies, even in the elderly [1]
[20]
[21]
[22]. We observed a non-significant age dependency with higher age groups being more often affected. A high percentage of study participants with depression had impairments in simple activities as well as more complex instrumental activities of daily living. This group also had higher probabilities of health care utilisation, especially visits of their general practitioner during the last 4 weeks. The latter finding is in line with studies supporting the key role for the general practitioner in the management of mental disorders [23]
[24]
[25].
The 7-day prevalence rate of 10.4 % for clinical manifest depression in our study is about 3-fold higher than in the Australian National Survey for DSM-IV defined depression in the previous 30-days [1]. Accountable for the lower prevalence in the Australian National Survey might be the applied diagnostic using the Composite International Diagnostic Interview (CIDI). A further explanation might be related to the sampling of both studies including different age groups [1].
Due to the cross-sectional study design we are unable to evaluate the sequence of depressive symptoms and impairments in activities of daily living and health care utilization. Thus, we cannot tell if in this study depressive symptoms caused impairment or if impairments due to other reasons caused depressive symptoms. In addition, a questionnaire based scoring algorhythm cannot replace the clinical diagnosis of depression. However, the questionnaire used in our study has shown high validity for manifest clinical depression if a cut off score of 16 is used.
In summary, our study results confirm those from other reports that depressive symptoms are prevalent among the elderly in the general population. Affected individuals show an increased health care utilisation and severe impairments in their daily functioning. Thus, primary health settings, especially the general practitioner or geriatric practitioner hold key roles for the detection and management of the depressed elderly patient.
Acknowledgement
Acknowledgement
The MEMO-Study is supported by the German Research Society (Deutsche Forschungsgemeinschaft, BE1996/1 - 1). Data assessment was done within the framework of the Cooperative Health Research in the Augsburg Region (KORA Study Group).
The article refers specifically to the following contributions of this special issue of Das Gesundheitswesen: [26]
[27]
[28]
[29]
[30]
[31]
[32].
