Patient Education and Counseling 41 (2000) 235–240www.elsevier.com/ locate /pateducou

Psychological distress of caregivers: moderator effects of caregiverresources?

a , b b*A.M. Pot , D.J.H. Deeg , R. van DyckaDepartment of General Practice, Nursing Home Medicine and Social Medicine, Vrije Universiteit, Amsterdam, The Netherlands

bDepartment of Psychiatry, Vrije Universiteit, Amsterdam, The Netherlands

Received 20 January 1999; received in revised form 27 July 1999; accepted 15 August 1999

Abstract

Personal psychological, social and health resources of informal caregivers are often assumed to attenuate or increasecaregiving stress. This hypothesis was tested by investigating the effect of caregivers’ resources on the relationship betweentheir appraisal of the caregiving situation and psychological distress. Caregiver resources measured were: problem-focusedand emotion-focused coping, neuroticism, received emotional and instrumental support and physical functioning. Resultsshow that none of these caregiver resources has moderator effects, neither for all caregivers together (n 5 166), nor forsubgroups of caregivers. These subgroups were: spouses, non-spouses, males, females, caregivers of minimally and mildlydemented people and of moderately and severely demented people, respectively. The absence of moderator effects oncaregiving stress suggests that caregivers of demented elderly people may need attention and support when they perceivepressure, regardless of their personal resources. 2000 Elsevier Science Ireland Ltd. All rights reserved.

Keywords: Caregivers; Dementia; Stress; Coping; Moderator

1. Introduction caregiving controls [1,2]. Several personal resourcesof informal caregivers, such as their coping strate-

Providing care to a demented relative has consid- gies, personality factors or social support received,erable consequences for caregivers. Several studies are often assumed to be conditioning variables in thehave shown that caregivers experience higher levels caregiving stress process [3,4]. For example, socialof psychological distress or (syndromal) depression support received by caregivers may attenuate thein comparison with the general population or non- impact of stressful aspects of the caregiving situation

on their psychological well-being. If this is the case,social support is called a buffer or a moderator [5].

*Corresponding author. Department HVSG, A-524, Vrije Uni-Research on moderator effects of caregiver re-versiteit, Van der Boechorststr. 7, 1081 BT Amsterdam, The

sources on caregiving stress is as yet relativelyNetherlands. Tel.: 1 31-20-4448237; fax: 1 31-20-4448231.E-mail address: am.pot.gpnh@med.vu.nl (A.M. Pot). undeveloped [6]. In the one case where the

0738-3991/00/$ – see front matter 2000 Elsevier Science Ireland Ltd. All rights reserved.PI I : S0738-3991( 99 )00081-6

236 A.M. Pot et al. / Patient Education and Counseling 41 (2000) 235 –240

moderator effect of coping strategies on the relation Caregiver resources included in this study are:between stressors in the caregiving situation and problem-focused and emotion-focused coping, neu-caregivers’ mental health was investigated no roticism and extraversion, received emotional andmoderator effects were found [7]. Most other studies instrumental support, and physical functioning. It iswere focused on main effects, rather than on hypothesized that caregivers who use more frequent-moderator effects of caregiver resources (such as ly problem- and emotion-focused coping strategies,social support, coping, personality, quality of the who are less neurotic and more extravert, whorelationship between caregiver and care-recipient and receive more emotional or physical support and whophysical functioning) on enduring outcomes, such as have a higher level of physical functioning have adepression (e.g., Refs. [8–12]). decreased risk of psychological distress under similar

In addition to stressors, caregivers’ perceived appraisal of the caregiving situation.stress or appraisal has been distinguished in severalcaregiving models as variables affecting their well-being [3,4,13,14]. In these models, perceived stressor appraisal is more critical to well-being than 2. Methodstressors in themselves. Moderator effects of caregiv-ers’ resources on the relation between their appraisal 2.1. Sampleof the caregiving situation and their psychologicalwell-being are still unexplored. The sample of caregivers for this study was partly

For understanding the caregiving stress process derived from an epidemiological study on cognitiveand indicating the focus of caregiver counseling, decline and dementia and partly derived from psy-knowledge on moderator effects of caregiver re- chogeriatric day hospitals and a memory clinic. As asources is indispensable. Moderator effects indicate result, not only help-seeking informal caregiverswhich caregivers are at greater risk for decreased providing care to relatively severely demented elder-psychological well-being under similar appraisal of ly care-recipients were included, but also caregiversthe caregiving situation. These caregivers need the of minimally and mildly demented elderly people. Inspecial attention of general practitioners, clinical this way, the variability in care-recipients was ex-workers and service providers. Moderator effects tended.also indicate which caregivers have a decreased risk The first source of selection, the epidemiologicalof psychological distress. This information may be study (Amsterdam Study on the Elderly: AMSTEL),helpful in developing intervention strategies for concerned the screening of an age-stratified samplecaregivers with an increased risk of psychological consisting of non-institutionalized community-baseddistress. elderly people (for more details on design and

Hence, the aim of this study is to test if caregiv- sampling methods, see Ref. [15]). Elderly wereers’ psychological, social and health resources mod- diagnosed as having dementia according to theerate the impact of their appraisal of the caregiving guidelines of the Cambridge Mental Disorders of thesituation on psychological distress (see Fig. 1). Elderly Exam (CAMDEX) [16]. This diagnosis and

classification of the degree of dementia correspondsto the DSM-III-R criteria. In addition, it also in-cludes a category ‘minimal dementia’. Minimallydemented elderly people have memory complaintsand are suspected of having dementia, but they stillcannot be classified as having dementia according tothe DSM-III-R criteria. Patients derived from thesecond source of selection, psychogeriatric dayhospitals, were diagnosed as having dementia bynursing home physicians using DSM-III-R. Subjects

Fig. 1. Moderator effect of caregiver resources. referred from the memory outpatient clinic, the third

A.M. Pot et al. / Patient Education and Counseling 41 (2000) 235 –240 237

source of selection, were diagnosed by a psychiatrist List’ (UCL) [20]. The scale ‘Problem-Solving’ wasor neurologist also using DSM-III-R. used as an indicator of problem-focused coping. It

The selected sample consisted of 175 informal consists of seven items to be scored on a four-pointcaregivers providing care to a demented older per- scale (a 5 0.79 in this sample). The scale ‘Palliativeson. All elderly with dementia in our sample lived in Reaction’ was used as an indicator of emotion-or near Amsterdam, The Netherlands, and none of focused coping. It consists of eight items to bethem were institutionalized. All caregivers satisfied scored on a four-point scale (a 5 0.74 in this sam-the following conditions: (1) providing care in one ple). Both scales measured coping as a trait ratheror more of the following ways: personal care, than as a state. Personality was measured by meansinstrumental care and/or supervision; (2) having at of the 12-item ‘Neuroticism’ and ‘Extraversion’least face-to-face contact with the older person once scale of the Revised Eysenck Personality Ques-every 2 weeks; (3) receiving no financial compensa- tionnaire Short Scale (EPQ-48-R) [21]. Reliability intion. this sample (Cronbach’s a) were 0.86 and 0.83,

If more than one caregiver was involved with the respectively. To avoid collinearity, the neuroticismolder person, the caregiver providing most of the score was excluded from the analyses, because it wascare was selected whenever possible. During home highly correlated with the GHQ score (r 5 0.63).visits, specially trained interviewers interviewed Informal support received by caregivers was mea-subjects and left questionnaires to be completed and sured using a two-step procedure [22]. First, areturned by subjects. The baseline data were col- network of supportive relationships was identified bylected between July 1991 and January 1993. asking names or initials of persons with whom

caregivers had regular and important personal con-2.2. Measures tact. Second, caregivers were asked to score seven

items concerning received support from their fiveTo measure caregiving appraisal we developed an most important personal relationships on a four-point

instrument for measuring ‘self-perceived pressure scale. In this study, Mokken analysis of the poly-from informal care’ in a previous study (SPPIC) chotomous data produced a weak scale. Therefore,[17]. Perceived pressure refers to the demands of the the responses on the items were dichotomised.caregiving situation in proportion to the personal Omitting one item, a three-item Mokken scale couldinterests of the caregiver. Caregivers’ personal inter- be developed for measuring instrumental support,ests refer to the room they need for other thoughts, with a moderate scalability coefficient (H 5 0.41)activities or roles. Examples of items are: ‘The and adequate reliability (r 5 0.65), and a three-itemsituation of my . . . constantly demands my atten- scale for emotional support (H 5 0.56; r 5 0.63)tion’ and ‘Owing to the situation of my . . . I have [23]. Physical functioning of caregivers was mea-too little time for myself’ (for all items translated sured using a questionnaire consisting of a transla-into English, see Ref. [14]). Caregivers were asked tion of 11 items of the Rand HIS questionnaires to beto score the items on a five-point scale. A nine-item scored on a two-point scale [24,25]. ReliabilityRasch-scale was developed, with an index of subject (Cronbach’s a) was 0.84 in this sample. A higherseparation of 0.66 (which indicates how well items score indicates more problems in physical func-discriminate between subjects) and reliability (r) of tioning.0.79.

Psychological distress was measured by the 12- 2.3. Analysisitem version of the General Health Questionnaire(GHQ) [18]. The Dutch translation of the GHQ-12 A moderator is a variable that alters the directionhas good psychometric properties. Reliability co- and/or strength of the relation between an indepen-efficients (Cronbach’s a) range from 0.86 to 0.97 dent or predictor variable and a dependent or criter-[19]. ion variable [5]. In this study, linear moderator

Caregiver resources: coping strategies were mea- effects were tested as described by Baron and Kennysured using two scales of the Dutch ‘Utrecht Coping [5]. A moderator effect is called linear when the

238 A.M. Pot et al. / Patient Education and Counseling 41 (2000) 235 –240

Table 1effect of the independent variable on the dependentMeans and standard deviations for measures used in this studyvariable changes gradually as the moderator changes.(n 5 165)

Linear moderation was tested using multiple regres-Measure M SDsion, adding the product of the moderator and the

independent variable to the regression equation [26]. Mental health (GHQ-12) 4.21 3.66Perceived pressure (SPPIC) 4.96 2.45To minimize multicollinearity between main effectsExtraversion (EPQ-48-R) 7.37 3.26and interaction effect in the regression equation, theProblem-focused coping (UCL) 17.53 3.99

product of the independent and moderator variable Emotion-focused coping (UCL) 16.70 4.00was based on deviation scores (cf. Ref. [27]). Instrumental support 5.87 4.05

After testing moderation for all caregivers to- Emotional support 11.11 3.64Physical functioning 1.71 2.37gether, the data were re-analysed for the following

subgroups of caregivers: (1) spouse (n 5 86) andnon-spouse (n 5 79) caregivers; (2) male (n 5 49)

Table 2and female (n 5 116) care-givers; and (3) caregivers Moderator effect of caregiver resources tested for associationsof minimally or mildly demented older persons (n 5 between caregiving appraisal and caregivers’ mental health

a(GHQ-12): regression results (n 5 165)95) and caregivers of moderately or severely de-2 2mented older persons (n 5 70). Thus, 36 regression Interaction b R DR

equations (six moderators 3 six subgroups) werePerceived pressure (SPPIC) with:

tested for these subgroups. For all caregivers to- Extraversion (EPQ-48-R) 2 0.01 0.19 0.00gether, the power of statistical testing to find a Problem-focused coping 2 0.01 0.20 0.00

Emotion-focused coping 2 0.05 0.19 0.01moderator effect was strong according to Cohen andInstrumental support 2 0.13 0.19 0.02Cohen [26]. The significance level of all tests wasEmotional support 2 0.11 0.19 0.01chosen as 0.05 [28].Physical functioning 2 0.03 0.30 0.00

a 2R is total variance explained by perceived pressure (SPPIC),caregiver resource and interaction between perceived pressure and

3. Results 2caregiver resource for mental health (GHQ-12); DR is varianceexplained by adding interaction to the regression equation; b

Ten of the 175 informal caregivers were excluded values are not significant.

from the analyses, because they did not have scoreson one of the variables. Half of the remaining 165caregivers were spouses (52.1%). Caregivers were to this finding, because at least two significantmore often female (70.3%) and had a mean age of moderator effects could have been expected by62.5 years. Demented care-recipients were also more chance regarding the 36 regression equations testedoften female (64.8%) and had a mean age of 78.2 for significance at the 0.05 level (results not shownyears. More than half of them were minimally or in table) [28].mildly demented (57.6%). The others were moder-ately or severely demented. Most caregivers livedtogether with the demented older person (58.8%). 4. DiscussionTable 1 shows means and standard deviations of themeasures used in this sample. We studied possible moderator effects of resources

Regression analyses showed, that perceived pres- of caregivers of dementing older persons, because itsure had a main effect on psychological distress has often been suggested that caregiver resources

2(b 5 0.42; R 5 0.18; P 5 0.00). For all six combi- attenuate the effect of perceived stress on mentalnations of caregiver resources and psychological health of caregivers.distress, no moderator interaction effects were found Our results do not support the hypothesizedin the total group of caregivers (see Table 2). In all moderator model of caregiving stress, at least forsubgroups, only one significant interaction was informal caregivers of demented elderly people. Thisfound. However, no importance should be attached study also shows absence of moderator effects for

A.M. Pot et al. / Patient Education and Counseling 41 (2000) 235 –240 239

subgroups, such as spouse and non-spouse caregiv- further investigate the differential effects of caregiverers, male and female caregivers, and caregivers of resources on the caregiving stress process.minimally or mildly demented elderly people andthose providing care to moderately or severelydemented elderly people. However, it must be noted 5. Practice implicationsthat the findings for these subgroups are less robust,because the power is less strong due to smaller What is the relevance of our results for profession-sample sizes, especially for male, non-spouse als involved with informal caregivers of dementedcaregivers. On the other hand, the variability in elderly people? These results indicate that caregiv-care-recipients was an important methodological ers’ appraisal of the caregiving situation is anstrength of this study. Caregivers of minimally and indication of their psychological distress, regardlessmildly demented patients were included, besides of their coping strategies, neuroticism, physicalmore severely demented patients. In addition, not functioning or the social support they receive. Thus,only help-seeking dyads of informal caregivers and if caregivers of demented elderly people perceivetheir demented elders were selected, but also non- much pressure they are in need of attention andhelp-seeking dyads. Accordingly, variability in support, regardless of their way of coping, neuro-caregivers resources may be expected in this study, ticism, physical functioning, or the emotional orwhich should facilitate the finding of moderator instrumental support they receive.effects. Our results are in agreement with those ofPruchno and Resch, who did not find moderatoreffects of coping styles for associations between Acknowledgementsstressors and caregivers’ psychological distress [7].

The absence of moderator effects on the relation- This research was supported by a grant from theship between caregivers’ appraisal and their psycho- Prevention Fund, The Hague, The Netherlands andlogical distress, may be explained in several ways. the University Stimulation Fund, Vrije Universiteit,First, caregiver resources may be moderators for Amsterdam, The Netherlands.other or more specific subgroups of caregivers thanmeasured in this study. For example, received in-strumental support may be a moderator only for Referencesyoung, female caregivers providing care to a severe-ly demented relative, rather than for all female [1] Schulz R, O’Brien AT, Bookwala J, Fleissner K. Psychiatriccaregivers. However, due to power limitations, it was and physical morbidity effects of dementia caregiving:

prevalence, correlates and causes. Gerontologistnot feasible to study such subgroups. Second, mea-1995;35:771–91.sures were focused on coping strategies and received

[2] Pot AM, van Dyck R, Deeg DJH. Psychological well-beingsocial support in general. Maybe the use of instru-of informal caregivers of elderly people with dementia:

ments more specifically focused on caregiver re- changes over time. Aging Ment Health 1997;1:261–8.sources in the caregiving situation would have shown [3] Pearlin LI, Mullan JT, Semple SJ, Skaff MM. Caregivingmoderator effects, for example caregivers’ methods and the stress process: an overview of concepts and their

measures. Gerontologist 1990;30:583–94.of coping with specific behavioral problems of the[4] Schulz R, Williamson GM. Psychosocial and behavioraldemented older person or received instrumental

dimensions of physical frailty. J Gerontol 1993;48(Specialsupport in connection with the care for the demented Issue):39–43.care-recipient. [5] Baron RM, Kenny DA. The moderator-mediator variable

Both explanations, not excluding one another, still distinction in social psychological research: conceptual,strategic, and statistical considerations. J Pers Soc Psycholassume the existence of moderator effects of care-1986;51:1173–82.giver resources on the relationship between caregiv-

[6] Schulz R. Theoretical perspectives on caregiving. Concepts,ers’ appraisal or perceived stress and their mental variables, and methods. In: Biegel DE, Blum A, editors,health. However, these effects are as yet unproven. Aging and caregiving. Theory, research and policy, Califor-The results of this study may stimulate researchers to nia: Sage Publications, 1990, pp. 27–52.

240 A.M. Pot et al. / Patient Education and Counseling 41 (2000) 235 –240

[7] Pruchno RA, Resch NL. Mental health of caregiving [17] Pot AM, van Dyck R, Deeg DJH. Ervaren druk doorspouses: coping as mediator, moderator, or main effect? informele zorg: constructie van een schaal [Self-perceivedPsychol Aging 1989;4:454–63. pressure from informal care: construction of a scale].

[8] Haley WE, Levine EG, Brown SL, Bartolucci AA. Stress, Tijdschr Gerontol Geriatr 1995;26:214–9.appraisal, coping, and social support as predictors of adapta- [18] Goldberg DP, Williams P. In: A users guide to the Generaltional outcome among dementia caregivers. Psychol Aging Health Questionnaire, Windsor: Nfer Nelson, 1988.1987;2:323–30. [19] Koeter MWJ, Ormel J. In: General Health Questionnaire,

[9] Hooker K, Monahan D, Shifren K, Hutchinson C. Mental Nederlandse bewerking handleiding [General Health Ques-and physical health of spouse caregivers: the role of per- tionnaire, Dutch version manual], Lisse: Swets & Zeitlinger,sonality. Psychol Aging 1992;7:367–75. 1991.

[10] Morris LW, Morris RG, Britton PG. Social support networks [20] Schreurs PJG, Willige G van de Tellegen B, Brosschot JF.and formal support as factors influencing the psychological In: De Utrechtse coping lijst [Utrecht coping list], Lisse:adjustment of spouse caregivers of dementia sufferers. Int J Swets & Zeitlinger, 1988.Geriatr Psychiatr 1989;4:47–51. [21] Eysenck HJ, Eysenck SBG. In: Manual of the Eysenck

[11] Pruchno RA, Kleban MH, Michaels JE, Dempsey NP. Personality Scales, London: Hodder & Stroughton, 1991.Mental and physical health of caregiving spouses: develop- [22] van Tilburg T. Question sequence effects in the measurementment of a causal model. J Gerontol 1990;45:192–9. of reciprocity. Qual Quant 1992;26:395–408.

[12] Williamson GM, Schulz R. Relationship orientation, quality [23] Mokken RJ, Lewis C. A nonparametric approach to theof prior relationship, and distress among caregivers of analysis of dichotomous item responses. Appl Psychol MeasAlzheimer’s patients. Psychol Aging 1990;5:502–9. 1982;6:417–30.

[13] Lawton MP, Moss M, Kleban MH, Glicksman A, Rovine M. [24] Brook RH, Ware JE, Davies-Avery A, Stewart AL, DonaldA two-factor model of caregiving appraisal and psychologi- CA, Rogers WA, Williams KN, Johnson SA. Overview ofcal well-being. J Gerontol 1991;46:181–9. adult health status measures fielded in RAND’s Health

[14] Pot AM, Deeg DJH, van Dyck R, Jonker C. Psychological insurance study. Med Care 1979;17:1–131.¨distress of caregivers: the mediator of effect of caregiving [25] Meyboom-de Jong B. Bejaarde patienten. Een onderzoek in

appraisal. Patient Educ Couns 1998;34:43–51. twaalf huisartspraktijken [Elderly patients. A study in twelve[15] Launer U, Dinkgreve MAHM, Jonker C, Hooijer C, Lin- general practices]. Dissertation. Lelystad: Meditekst, 1989.

deboom J. Are age and education independent correlates of [26] Cohen J, Cohen P. In: Applied multiple regression /correla-the Mini-Mental State Exam performance of community- tion analysis for the behavioral sciences, Hillsdale, NJ:dwelling elderly? J Gerontol 1993;48:271–7. Lawrence Erlbaum Associates, 1983.

[16] Roth M, Tym E, Mountjoy CQ, Huppert FA, Hendrie H, [27] Cronbach LJ. Statistical tests for moderator variables: flawsVerma S, Goddard R. CAMDEX. A standardized instrument in analyses recently proposed. Psychol Bull 1987;102:414–7.for the diagnosis of mental disorder in the elderly with [28] Stevens J. In: Applied multivariate statistics for the socialspecial reference to the early detection of dementia. Br J sciences, Hillsdale, NJ: Lawrence Erlbaum Associates, 1986,Psychiatr 1986;149:698–709. pp. 6–8.