Factors Associated with Symptoms of Depression Amoog Informal Caregivers of Demented Elderly in the Community. INTRODUCTION A substantial body of research has documented a variety of mental and physical health problems among informal caregivers of persons with dementia. Depression is an important health problem that has been associated with caregiving for demented persons. Depression can interfere with ability to function normally. Even symptoms of depression that do not meet conventional criteria for depressive disorders may have a sign)ficant effect on functional status. Furthermore, depression is often treatable using pharmacological and/or psychosocial approaches. However, physicians often fail to recognize depressive - .rders in general medical settings, and hence these problems are often not treated. The identification ~. a treatment of depression in caregivers has the potential to improve their functioning and ability to continue to provide care, thus reducing the need for institutional care. In order to plan appropriate services for informal caregivers, it is important to know the factors that are associated with increased severity of symptoms of depression. A number of previous studies have addressed this question, but there are methodological limitations and the results are not entirely consistent. The objective of this study is to determine whether the severity of depressive symptoms among informal caregivers of demented subjects living in the community is related to selected characteristics of both patients and their caregivers. The relevant data for this study are a subset of a large population-based national survey of dementia, namely the Canadian Study of Health and Aging (CSHA). The CSHA recently estimated that the prevalence of dementia was 8% in the Canadian population 65 years and older, with markedly increased rates at older ages (Canadian Study of Health and Aging Working Group, 1994). In the community-based sample of the CSHA, the prevalence of depression (using the Center for Epidemiologic Studies Depression Scale (CES-D)) was 25.9% in the caregivers of patients with dementia versus 13.8% among caregivers of nondemented patients. Elevated rates of chronic health conditions were also found among caregivers of the demented versus nondemented patients. METHODOLOGY Sample Selection The study methods used in the CSHA are described in detail elsewhere (Canadian Study of Health and Aging Working Group, 1994). Briefly, the study sampled 9,008 people aged 65 and over from the community in 36 urban centers and surrounding rural areas across Canada in 1991-92. The community samples were drawn from the computerized records of the provincial health insurance plans, except in Ontario where the Enumeration Composite Record (an aggregated list based on election and other municipal records) was used. Random samples were drawn in the age strata 65-74, 75-84, and 85 and over, the sampling fractions in the two latter age strata were 2 and 2.5 times, respectively, that of the 65 to 74 age group. Subjects in the community were screened for cognitive impairment, using the Modified MiniMental State Exam (3MS) (Ten" & Chui, 1987). Those who screened positive (below cut-off point of 78), and a sample of those who screened negative were referred for a clinical examination that consisted of a neuropsychological test battery (for subjects with a score of 50 or more on the 3MS exam), and physician assessment of mental, physical, and neurological status. The final consensus diagnosis of dementia was made at a case conference. The primary caregiver was identified through an interview with the elderly subject and, in most instances, through discussions with other family members. The primary caregiver was defined as the person who was ordinarily the most responsible for the day-to-day decision-making and care of the index subject. Primary caregivers could be formal (paid) or informal (unpaid). When both formal and informal caregivers were involved, the informal caregiver was interviewed if he or she was in contact with the index subject at least once a week. Interviews were conducted with the caregiver, usually in his or her home, to assess the patient's ability to perform activities of daily living, the presence of behavioral problems in the patient, and depressive symptoms in the caregiver. The CSHA identified 395 subjects with dementia in the community; seven had no primary caregiver who met the selection criteria, 39 caregivers could not be contacted or declined to participate, and 22 had formal caregivers only. Among the sample of 327 informal caregivers who were interviewed, 42 were excluded because their CES-D score was missing. Thus, the sample for this study comprised 28S caregivers. STUDY VARIABLES (listed in order of appearance in the data file caregive.dat): 1. ID: patient identification number (1 to 285) Dependent variable: 2. The depressive symptoms were assessed by the Center for Epidemiologic Studies Depression Scale (CES-D) (Radloff, 1977; Radloff & Teri, 1986). The CES-D comprises 20 items, each rated on a fourpoint response scale (O to 3) corresponding to the frequency of the symptom in the preceding week. The CES-D score is simply the sum of the responses over the 20 items. The possible range of CES-D scores is 0-60, with a higher score indicating more severe symptoms. Independent Variables A. Caregiver demographic characteristics: 3. caregiver age (in years) 4. caregiver gender (O=male, 1=female) 5. caregiver number of years of education 6. caregiver ethnic background (O=English Canadian, 1=French Canadian, 2=other) note: ethnicity was measured by the response to an open-ended question about the caregiver's ethnic or cultural background. 7. caregiver relationship to the patient (O=spouse, 1=child, 2=other) 8. caregiver current employment status (O=not working, 1=worhag) 9. caregiver living arrangement (O=not living with patient, 1= living with patient) B. Patient variables: 10. patient age (in years) 11. patient gender (O-~ale, 1=female) 12. patient number of years of education 13. patient duration of dementia (O=less than 1 year, 1 =between I and 3 years, 2=more than 3 years) 14. patient activities of daily living (ADL) questionnaire developed for the Older American Resources and Services Project (Fillenbaum, 1988). The caregiver rated the patient's ability to perform 14 tasks with or withhout assistance. An algorithm was used to arrive at a rating on a five- point ordinal scale: no, mild, moderate, severe, and complete impairment. This scale was further categorized in three categories: 0 = no or mild impairment; 1 = moderate impairment; and 2 = severe or complete impairment. 15. Dementia Behaviour Disturbance (DBD) Scale (Baumgarten, Becker, & Gauthier, 1990). The DBD scale evaluates behavioral disturbances in persons with dementia. It includes 28 items such as passivity, agitation, aggressiveness, sexual misdemeanor, and disturbances in eating and diurnal rhythm. Each item is rated on a five point scale ranging from "never" (score of O) to "all the time" (score of 4) in the preceding week. The theoretical scale range is O to 112, with a higher score indicating more behavioral disturbance. REFERENCES Baumgarten, M., Becker, R., & Gauthier, S. (1990). Validity and reliability of the Dementia Behaviour Disturbance scale. Journal of the American Geriatrics Society, 38, 221-226. Canadian Study of Health and Aging (1994). Patterns of caring for people with dementia in Canada. Canadian Journal on Aging, 13, 470-487. Canadian Study of Health and Aging Working Group (1994). The Canadian Study of Health and Aging: study methods and prevalence of dementia. Canadian Medical Association Journal, 150, 899-913. Fillenbaum, G.G. (1988). Multidimensional Functional Assessment of Older Adults: The Duke Older Americans Resources and Services Procedures. Hillsdale,NJ: La~`Tence Erlbaum Associates. Radloff, L.S. (1977). The CES-D scale: a self-report depression scale for research in the general population. Applied Psychological Measurement, 1, 38S 401. Radloff, L.S., & Teri, L. (1986). Use of the Center for Epidemiologic Studies-Depression scale with older adults. In: Brink, T.L. (Ed), Clinical Gerontolo~: A Guide to Assessment and Intervention. New York: Haworth. Teng, E.L., & Chui, H.C. (1987). The Modified Mini-Mental State (3MS) Examination. Journal of Clinical Psychiatry, 48, 314-318.