dynandcs in cancer caregiver's health over time: gender-specific patterns and determinants
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Dynandcs in cancer caregiver's healthover time: Gender-specific patternsand determinantsChris Nijboer a e f , Reike Tempelaar b , Mattanja Triemstra c g ,Robert Sanderman d e & Geertrudis A.M. van den Bos ca Department of Social Medicine, Academic Medical Center ,University of Amsterdamb Northern Centre for Healthcare Research , University ofGroningen , Groningen, The Netherlandsc Department of Social Medicine, Academic Medical Center ,University of Amsterdam , The Netherlandsd Northern Centre for Healthcare Research , University ofGroningen , Groningene Department of Clinical Psychology , University of Groningen ,Groningen, The Netherlandsf The National Institute for Health Promotion and DiseasePrevention Woerden , The Netherlandsg Department for Health Services Research , National Instituteof Public Health and the Environment RIVM , Bilthoven, TheNetherlandsPublished online: 19 Dec 2007.
To cite this article: Chris Nijboer , Reike Tempelaar , Mattanja Triemstra , Robert Sanderman& Geertrudis A.M. van den Bos (2001) Dynandcs in cancer caregiver's health over time:Gender-specific patterns and determinants, Psychology & Health, 16:4, 471-488, DOI:10.1080/08870440108405520
To link to this article: http://dx.doi.org/10.1080/08870440108405520
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Psychologyand Healrh, 2001, Vol. 16, pp. 471488 Reprints available directly from the Publisher Photocopying permitted by license only
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DYNAMICS IN CANCER CAREGIVER’S HEALTH
DETERMINANTS OVER TIME: GENDER-SPECIFIC PATTERNS AND
CHRIS NIJBOER’.*, REIKE TEMPELAAR’, MA’ITANJA TRIEMSTRA’, ROBERT SANDERMAN4 and GEERTRUDIS A.M. VAN DEN BOS’
‘Department of Social Medicine, Academic Medical Center, University of Amsterdam, Northern Centre for Healthcare Research, University of
Groningen, Groningen, and The National lnsriture for Health Promotion and Disease Prevention, Woerden, The Netherlands
2Northern Centre for Healthcare Research, University of Groningen, Groningen, The Netherlands
‘Department of Social Medicine, Academic Medical Center, University of Amsterdam, The Netherlands, and Department for Health
Services Research, National Institute of Public Health and the Environment, RIVM, Bilthoven, The Netherlands
4Northern Centre for Healthcare Research, University of Groningen, Groningen, and Department of Clinical Psychology, University of
Groningen, Groningen, The Netherlands
(Received 10 February, 2000; in finalform 10 October, 2000)
This study examined patterns and determinants of three dimensions of caregiver’s health of newly diagnosed colorectal cancer patients, i.e. physical, mental and social functioning ( N = 148). Physical functioning declined within a 6-month period in female caregivers, while no change was observed in male caregivers. For mental and social functioning, an improvement was observed in male and female caregivers. Change in physical functioning was associated with gender, age, income and initial level. Change in mental functioning was predicted by initial status and positive as well as negative caregiver experiences. Change in social functioning was mainly predicted by initial level and change in patient’s dependency. Physical and mental functioning showed the least favorable patterns in female caregivers. The study shows that caregiving may lead to positive health consequences, and underlines the importance of making a distinction between male and female caregivers and of studying caregiver outcomes by using multidimensional assessments.
KEY WORDS: Cancer, caregivers, gender, physical functioning, mental functioning, social functioning.
INTRODUCTION
Along with the development of medical technologies, earlier hospital discharges and longer survival times, the care at home for seriously ill patients, e.g. cancer patients, has expanded and changed. As informal caregivers, and in particular partners, have a substantial and increasing role in providing care, it becomes crucial to understand the associations and
*Corresponding author. Tel.: 31 348 439 876; Fax: 31 348 437 666; E-mail: [email protected].
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412 C. NIJBOER ETAL
dynamics between patient and care characteristics on the one hand, and caregiver’s health on the other.
Many studies have tried to document both the physical and mental health consequences of the caregiving role. For example, several researchers suggest that the physical health of caregivers is poorer than that of non-caregivers (Goode, Haley, Roth and Ford, 1998; Kiecolt-Glaser, Dura, Speicher, Trask and Glaser, 1991). It has also been reported that caregivers experience lower life-satisfaction (Haley, Levine, Brown and Bartolucci, 1987), greater distress (Anderson, Linto and Stewart-Wynne, 1995; Pruchno and Potashnik, 1989), and elevated levels of depression (Schulz, O’Brien, Bookwala and Fleissner, 1995). As caregiving is time-consuming, it may lead to social health consequences too, e.g. in terms of feelings of being isolated or being restricted to participate in social activities (Bass, McClendon, Deimling and Mukherjee, 1994; Schulz and Williamson, 1991). Most of these findings are based on cross-sectional data. Since caregiving may be seen as an ongoing, dynamic process, a longitudinal design is warranted (Kurtz, Kurtz, Given and Given, 1995; McCorkle, Yost, Jepson, Malone, Baird and Lusk, 1993).
Relations between patients’ health and caregivers’ health are empirically supported, even though the associations reported are low to moderate and the individual caregiver variability is found to be high (Biegel, Sales and Schulz, 1991; Schulz er al., 1995). The usual approach to study caregiver’s health consequences is based on the cognitive stress theory of Lazarus and Folkman (1984). According to this theory, caregiver’s health adjust- ment is a function of the complex interplay of contextual and appraisal-related factors (Pearlin, Mullan, Semple and Skaff, 1990). Contextual factors may include caregiver’s background characteristics (e.g. socio-demographic characteristics and initial values of health dimensions) and stressors (e.g. patient’s dependency and number of care tasks), while appraisal-related factors refer to caregiver’s personal experiences. Although this stress model has rarely been used in a longitudinal study design, the elements of this model are not static, and changes in any of the variables are expected to alter relationships within the caregiving process. These changes and effects may particularly be true in the first period of the caregiving career (Shewchuk, Richards and Elliot, 1998), as family members are just assuming the caregiver role.
Much of the previous research on caregiving focused on negative caregiver consequences, e.g. care burden, strain or depression. As yet, research revealed that positive caregiver experiences may also occur, e.g. in terms of satisfaction (Lawton, Kleban, Moss, Rovine and Glicksman, 1989), gain (Kramer, 1997), gratification (Motenko, 1989), positive psy- chological states (Folkman, 1997) and self-esteem derived from caregiving (Given, Given, Stommel, Collins, King and Franklin, 1992). Since contextual and appraisal-related factors are expected to influence caregiver health outcomes, positive caregiver experiences may balance negative caregiver health effects or they may lead to positive effects on health. In a recent study among spouses of bypass operation patients, many of these patients showed improved functional ability over time (Nieboer, Schulz, Matthews, Scheier, Ormel and Lindenberg, 1998), and consequently a decrease in caregiving demands reduced levels of caregivers’ depressive symptoms.
For a diagnosis such as cancer, longitudinal research on the relation between the patients’ health and caregiver’s health is scarce (Northouse and Swain, 1987; Oberst and James, 1985; Oberst and Scott, 1988). Only a few longitudinal studies focused specifically on the caregiving situation of patients with cancer (Kurtz et al., 1995; Kurtz, Kurtz, Given and Given, 1997; McCorkle et al., 1993). Caring for a person with cancer is often complex, demand- ing and varying over time (Oberst and James, 1985; Oberst and Scott, 1988). It may include
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CANCER CAREGIVER’S HEALTH 473
managing the physical care (e.g. assisting the patient with personal and disease-related care), managing the household and finances and providing emotional support (Stetz, 1987).
In the case of newly diagnosed colorectal cancer, for which surgery is the primary choice of treatment and a number of patients will get a temporary or permanent stoma (Otte, 1988), patients’ needs may be high at first. The mean hospital stay is short, about 10 days. At discharge, patients may frequently experience impaired bowel and sexual function, psy- chological distress and restrictions in social functioning (Sprangers, Taal, Aaronson and Te Velde, 1995). Subsequently, this may involve specific and extra demands for the caregiver. Care tasks may be diverse, e.g. taking care for wound or stoma, preparing special food, or assisting with making decisions regarding future treatment. Apart from performing these tasks and having to cope with the diagnosis of cancer, family members may be forced to adjust their family and occupational roles, life-styles and patterns of living (Hoskins, Baker, Budin, Ekstrom, Maislin, Sherman, Steelman-Bohlander, Bookbinder and Knauer, 1996; Northouse, 1988; Northouse and Stetz, 1989).
However, caring for persons with cancer is assumed to be less difficult and burdensome than caregiving for relatives with cognitive disorders, like dementia (Light, Niederehe and Lebowitz, 1994; Ory, Hoffman, Yee, Tennstedt and Schulz, 1999). This might particularly be true as, the course of the illness of many newly diagnosed colorectal cancer patients is expected to improve after treatment (McCorkle et al., 1993; Otte, 1988), and changes in caregiver’s health (i.e. mental health) are expected to occur relatively rapidly in response to the situation of the patient (Kurtz et al., 1995). As far as we know, no longitudinal research has been conducted that examines physical, mental and social dimensions of health all at once in caregivers of patients with cancer. Although research findings indicate that patient’s dependency and need for assistance may influence caregivers’ health over time (Carey, Oberst, McCubbin and Hughes, 1991; Kurtz et al., 1997; Oberst, Thomas, Gass and Ward, 1989; Schott-Baer, 1993), little is known about the patterns of caregivers’ health following the course of newly diagnosed cancer patients and about what factors could predict these patterns.
As most research considered family caregivers as a homogeneous group, this may mask considerable differences between certain types of caregivers, not only in the patterns of caregiver outcomes, but also in the predictability of these patterns. Some studies focused on differences between men and women in their enactment of the caregiving role in particular (Barusch and Spaid, 1989; Miller and Cafasso, 1992; Neal, Ingersoll-Dayton and Starrels, 1997; Rose-Rego, Strauss and Smyth, 1997), and it appears that men and women perform different amounts and types of care. Women are likely to provide more care than men, and if men conduct care tasks they are more likely to engage in care management, transporta- tion or assistance with occasional tasks (Neal et al., 1997). There are indications that care- giving is experienced differently and less stressful by husbands than by wives (Horowitz, 1985; Siegel, Raveis, Mor and Houts, 199 I) . Is this -just and only -a gender effect or does gender moderate the effect on caregiver health consequences? For example, do men who experience caregiving as stressful report negative health consequences too? Apart from gender differences concerning the specific caregiving situation, health adjustment in general has been shown to differ according to gender, age and income. It is well recognized that women, people of a higher age, and those with a lower income tend to report poorer health states than their counterparts (Kaplan, Anderson and Wingard, 1991 ; Stronks, 1997; Van der Zee and Sanderman, 1994).
The present study focuses on the caregivers of newly diagnosed colorectal cancer patients and the (negative and positive) care consequences during the first period of the
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414
Physical functioning
Mental hnctioning
Social functioning ___._--
C. NIJBOER ETAL
Baseline characteristic!
Caregiver background Initial health status
Socio-demographic char.
Patient characteristics
Level of dependency
Care characteristics
Number of care tasks
Caregiver experiences
Changes in the caregiving situation
Patient characteristics
Level of dependency
Care characteristics Vumber of care tasks
Caregiver exDeriences
Caregiver’s health outcomes
Figure 1 Basic research model for examining changes in three dimensions of caregiver’s health.
caregiving career, i.e. in the first 6 months after diagnosis. Figure 1 provides a basic research model for examining three dimensions of caregiver’s health over time in relation to patient and care characteristics. Although this model does not claim to be exhaustive, it delineates the variables of interest in this study.
The main purpose of this study is twofold. First, to describe patterns of caregiver health outcomes, i.e. physical, mental and social dimensions of caregiver’s health, together with changes in patient and care characteristics. And secondly, to examine patterns of caregiver’s health in relation to caregiver’s background characteristics, patient characteristics and care characteristics. In particular, the role of gender within the process of caregiving will be examined, i.e. gender and gender interaction effects. We hypothesize that many patients will improve after surgical treatment in the first 6 months after diagnosis, and positive changes in caregiver’s health will occur in response. More specifically, the level of patient dependency and number of care tasks are expected to decrease over time, less negative and more positive caregiver experiences are likely to be observed and, consequently, caregiver’s health are expected to improve over time. Secondly, changes in caregiver’s health are expected to show less favorable patterns in female caregivers than in male caregivers.
METHODS
Subjects
This present study is part of the research project entitled: “CAregiving of Spouses of cancer PAtients” (CASPA), which was conducted in co-operation with 10 hospitals in the Nether- lands in the regions of Amsterdam and Groningen. Newly diagnosed colorectal cancer patients who had recently undergone surgery, who had a survival prognosis of at least 6 months, and who lived with a partner (i.e. the person who wadlived as married to the patient at the onset of the study) were listed. Thereafter, the surgeon in charge was contacted to ask if any objections (e.g. medical, psychological or social) were present to approach
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CANCER CAREGIVER’S HEALTH 415
the patient and partner for their participation in this study. A more complete description of the recruitment procedures can be found elsewhere (Nijboer, Triemstra, Tempelaar, Sanderman and Van den Bos, 1999).
Of the 238 eligible cancer patients and their caregivers, 181 gave their informed consent at the onset of the study. The response percentage was 76%. No response bias was found between participating patients and non-participants with respect to age, gender, diagnosis and region. Longitudinal data (over a 6-month period) were available for 148 couples (82%). Loss to follow-up occurred for the following reasons: serious illness of the patient (n = 15; 8%), refusal to follow-up (n = 10; 6%) and patient’s death (n = 8; 4%).
Patients who were lost to follow-up did not differ from patients who remained in the study regarding gender, age, diagnosis, duration of complaints and mental functioning. However, the proportion of patients with a stoma was slightly higher among those who dropped out ( p c .lo). Also, patient dependency in those who dropped out were signific- antly higher at baseline than patients who could be followed for 6 months (p<.O5). Caregivers of patients who were lost to follow-up did not differ from those who remained in the study regarding gender, age, and the baseline values of the caregiver experiences.
Measures
Caregiver background characteristics included gender, age income and initial health states. Gender, age and income were measured with single items. Income was categorized into three levels: low (up to 40.000 H F1 (or about up to 20,000 US$)), middle (40.000 to 60.000 H F1 (i.e. 20,000-30.000 US$)) and high (60.000 H F1 and over (i.e. > 30,000 US$)).
Caregiver’s initial health states included three dimensions, “physical functioning”, “mental functioning” and “social functioning”, which were measured by three subscales of the RAND 36-item Health Survey (Rand Health Science Program, 1992; Van der Zee, Sanderman, Heyink and De Haes, 1996). The scale for physical functioning (10 items) concerns caregiver’s limitations in performing daily activities, such as walking stairs, bathing or dressing oneself, or carrying groceries as a result of health problems; answering categories ranged from 1 (=yes, seriously limited) to 3 (= no, not at all limited). The scale for mental functioning (5 items) contains questions about the occurrence of feelings of depression and nervousness with a response format ranging from 1 (=continuously) to 6 (= never). The scale of social functioning (2 items) measures caregiver’s limitations in social activities such as visiting friends or relatives and answers could range from 1(= not at all restricted) to 5 (=strongly restricted). Item scores were summed to compute scale scores and these scores, in turn, were transformed into scores with a possible range between 0 (= worse health) and 100 (=best health).
Patient characteristics included disease specific variables (i.e. diagnosis, whether a stoma was present, duration of complaints) and level of patient dependency. The level of patient dependency was measured by asking the patient about the number of disabilities in activities of daily living (ADL) and instrumental activities of daily living (IADL) by means of the Groningen Activity Restriction Scale (GARS; Kempen and Suurmeijer, 1990; Kempen, Miedema, Ormel and Molenaar, 1996). This hierarchical 18-item scale was used to assess the extent of (dis)ability to manage (1) ADL, such as eating, dressing, bathing, grooming, and getting in and out of bed (1 1 items) and ( 2 ) IADL, such as cooking, laundry, shopping and housework (7 items). Each item was scored on a Likert-scale, with a response format ranging from 1 (=can do it without any difficulty) to 4 (=cannot do it independently, I can only do it with someone’s help). A dependency score was determined by summation
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476 C. NIJBOER ETAL.
of the item scores and it ranged between 18 (absence of dependency) and 72 (totally dependent). In this study, the Cronbach’s (Y of the GARS was found to be 0.8 1.
Care characteristics referred to the number of care tasks and caregiver experiences. The number of care tasks was measured by asking the caregiver if he or she assisted the patient by conducting four different types of tasks, i.e. personal tasks, household, organ- izational and disease-related tasks. Personal tasks referred to assisting the patient with activities of daily living (1 1 items, e.g. assistance with eating, dressing, bathing and get- ting in and out of bed). Household chores (7 items) included cooking, laundry, shopping, and housework. Organizational tasks (5 items) focused on providing assistance with large expenses, transport and providing odd jobs. Disease-related tasks (6 items) referred to wound and stoma care, decision-making, and achieving information. For each type of task, the response format was dichotomized (0 =did not; 1 =did assist with specific task). A sum score was computed for each type of task ranging from 0 to 4. Cronbach’s (Y in this study was 0.68.
Caregiver experiences were measured by two subscales of the Caregiver Reaction Assessment Scale (CRA) of Given et al. (1992), including a negative and a positive dimen- sion. The subscale “disrupted schedule” (5 items) measured the extent to which caregiving interfered with the usual daily activities of the caregiver. For example, “I have to stop in the middle of my work to provide care”. The subscale “care-derived self-esteem” (7 items) aimed to measure the extent to which caregiving contributed to individual self-esteem. For example, “Caring for my partner makes me feel good”. Respondents were asked to rate the perceived impact of caregiving on each of the items on a Likert-scale with the response format ranging from 1 (=strongly disagree) to 5 (= strongly agree). For each subscale, a total score was computed by adding the total item score divided by the number of items. A high score represented a great amount of the attribute. The subscales of the Dutch CRA were shown to be reliable (Cronbach’s a’s were 0.84 and 0.73, respectively) and valid (Nijboer et al., 1999).
The three dimensions of caregiver’s health included physical, mental and social function- ing, and were, similar to the measurement at baseline, assessed with the RAND 36-item scale.
Data Collection
Data were collected at three measurement points over a period of 6 months. Baseline meas- urement (To) took place as soon as possible after patient’s diagnosis on one to two weeks after hospital discharge. At this measurement point, information was gathered retrospect- ively, referring to two weeks before hospital admission. The second measurement (T,) took place 3 months after baseline and the third measurement (T2) occurred again 3 months later (i.e. 6 months after baseline). Data on caregiver’s background characteristics and patient disease specific variables were collected only at To, whereas data on patient and care characteristics, and levels of caregiver’s functioning were assessed at all waves (i.e. T,,, T, and TJ.
Data were gathered separately from the patient and the caregiver at the same time. While data regarding caregiver’s health dimensions were obtained by means of written self-report questionnaires, all other data were collected by means of structured face-to-face interviews. Patient characteristics (i.e. diagnosis, the presence of a stoma, duration of complaints, and patient dependency) were all obtained from the patients themselves. Care and caregiver characteristics, including the three dimensions of caregiver’s health, were obtained from the partners.
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CANCER CAREGIVER’S HEALTH 411
Analyses
Firstly, descriptive statistics were computed for all relevant background variables at base- line (To). >? tests were performed to test for gender differences in sample characteristics. Also, zero-order correlations were computed for patient, care and caregiver characteristics at baseline. Changes in patient, care and caregiver characteristics over time and gender- interaction effects were examined by means of General Linear Model (GLM) Repeated Measurement Analyses of Variances for the total group with the baseline measurement point being used as the reference point. In addition, the significance of changes over time, both within and between gender subgroups were examined.
Secondly, regression analyses were performed for which change scores were computed for the patient and care characteristics. Even though it would have been possible to use a change score for caregiver health outcomes too, the approach in which caregiver’s health at baseline was used as a predictor for health at wave 3 was preferred, because it retains information about the absolute level of caregiver’s health. The variables were entered in three blocks conform the way they are displayed in Figure 1: (1) caregiver background characteristics, i.e. initial health states, gender, age and income ( 2 ) patient and care characteristics (i.e. patient’s dependency, number of care tasks and caregiver experiences); and (3) changes in patient and care characteristics (T(,-TJ. Each set of variables was simultaneously tested and adjusted for all other variables entered. Thus, the relative contribution of each set of variables could be determined. Model fit was evaluated by the change in R2 and final adjusted ,B weights. Listwise deletion of missing data was applied. Residual analyses were performed to ensure that the mul- tiple regression assumptions of linearity, constant error variance, and normality were adequately met.
Thirdly, to test gender-specific determinants of caregiver health patterns, gender and gender interaction terms (i.e. gender combined with other independent variables) were added to the regression equations for each of the three health outcome measures. Determinants involved in the interaction were centered and entered into the equation simultaneously with the product term (Aiken and West, 1991; Jaccard, Turrisi and Wan, 1990). Each interaction test also included all determinants from the previous regression analysis as covariates. Only significant interactions were presented in figures.
RESULTS
Sample
Table 1 presents sample characteristics of the 148 dyads that participated at all three waves. The caregiver group consisted of 54 men and 94 women, ranging in age from 25 to 89 years (with a mean age of 63 years, SD= 11 years). Male and female caregivers did not differ significantly regarding patient’s diagnosis, the presence of a stoma, duration of patient’s complaints, or regarding caregiver’s age, income and work situation.
Zero-order correlations among caregiver background characteristics, patient and care characteristics, and the three dimensions of caregiver’s health, all measured at baseline, are presented in Table 2. Income and care-derived self-esteem were positively related with caregiver’s physical functioning, and caregiver’s age was negatively related with physical functioning. Patient’s dependency was negatively related with caregiver’s mental functioning. Number of care tasks and impact on schedule were negatively related with caregiver’s
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478 C. NIJBOER ETAL.
Table 1 Sample characteristics of patients and caregivers (To) according to gender ( N = 148)
Categories Total Male caregivers Female caregivers
n = 94 (%) N = 148 (%) n = 54 (%)
Patient Is characteristics Diagnosis
Stoma
Duration complaints in months
Caregiver’s characteristics Age
Income
Work situation
Colon cancer Rectum cancer No Yes 0-3 4-6 7-12 > 12
< 50 years 50-65 years > 65 years Unknown Low Middle High Yes No
96 (65) 52 (35) 99 (67) 49 (33) 50 (34) 43 (29) 34 (23) 21 (14)
18 (12) 69 (47) 61 (41) 31 (21) 38 (26) 51 (34) 28 (19) 32 (22)
116 (78)
32 (59) 22 (41) 39 (72) 15 (28) 14 (26) 15 (28) 15 (28) 10 (19)
6 ( 1 1 ) 23 (43) 25 (46)
14 (26) 17 (32) 14 (26) 15 (28) 39 (72)
9 (17)
64 (68) 30 (32) 60 (64) 34 (36) 36 (38) 27 (29) 20 (21) I 1 (12)
12 (13) 45 (48) 37 (39) 22 (23) 24 (26) 34 (36) 14 (15) 17 (18) 71 (82)
social functioning at baseline. Caregiver’s gender was not significantly related to any dimen- sion of the caregiver’s health at baseline.
The patients’ disease specific characteristics, like diagnosis, the presence of a stoma and duration of complaints, were not significantly associated with caregiver’s functioning.
Changes in Patient Characteristics, Care Characteristics and Caregiver’s Health
Mean values of patient and care characteristics and caregiver health outcomes are presented in Table 3 for the total group, and for male and female caregivers separately. For the total
Table 2 Zero-order correlations of caregiver’s background characteristics, patient and care characteristics and caregiver’s health at baseline
Vuriable 1 2 3 4 5 6 7 8 9 1 0
Caregiver’s Background Characteristics
1. Gender - 2. Income -.02 - 3. Age -.05 -.27**
Patient and Care Characteristics 4. Patient dependency -.07 .08 .08 -
6. Disrupted schedule .03 -.01 -.I4 -.03 .25** - 7. Care-derived self-esteem .I0 -.06 . I 1 -.05 .02 -.06 -
5. No.Tasks .04 .01 . l l .09 -
Caregiver’s health 8. Physical Functioning .01 .24** -.28** -.I5 .I0 -.01 .17* -
9. Mental Functioning .10 .17* .10 -.18*-.03 -.I1 -.06 .22** - 10. Social Functioning -.02 .08 -.05 -.11 -.18* -.33** -.08 .29** .54** -
* p c .05; ** p < .01
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Tab
le 3
M
eans
of p
atie
nt a
nd c
are c
hara
cter
istic
s an
d th
ree d
imen
sion
s of c
areg
iver
's he
alth
at b
asel
ine
(To)
and
at th
ree
(T,)
and
6 m
onth
s aft
er ba
selin
e (T,) an
d ch
ange
s ove
r tim
e by
usi
ng G
LM re
peat
ed m
easu
rem
ent a
naly
ses
of v
aria
nces
Tota
l gro
up N
= 1
48
Mal
e ca
regi
vers
n =
54
Fem
ale
care
give
rs n
= 9
4
To
*, T2
F
rrm
f2.29
4)
To
T,
T2
F7t
mc(
Z105
, TO
TI
T2
F7,n
.(*.1861
FG
mde
ll
1461
FT
x G
(2.2
921
Patie
nt's
depe
nden
cy
No.
Tas
ks
Dis
rupt
ed
Sche
dule
Car
e-de
rived
se
lf-es
teem
Phys
ical
Fu
nctio
ning
Men
tal
Func
tioni
ng
Soci
al
Func
tioni
ng
20.1
2.41
2.42
4.22
84.4
66.9
78.4
21.7
**
2.28
2.20
**
4.13
***
80.4
***
71.9
***
79.3
20.8
4.
20*
20.4
21
.4
.05
.34
.70
.60
1.31
1.
25
.86
.48
1.29
5.
32**
4.23
* 1.
20
2.05
1.
51
2.20
**
3.53
* 2.
47
2.28
1.98
****
18
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group, patient’s level of dependency showed to be higher at 3 months after baseline. However, within the gender subgroups, the significance of change disappeared.
There was a slight, but significant decrease in the mean total number of care tasks over time. Separate analyses showed that this pattern was only observed in male caregivers. In general, female caregivers did perform more care tasks than male caregivers ( p c .05), in particularly household tasks (not shown in Table). With regard to caregiver experiences, both the impact on schedule and the impact on self-esteem decreased over time, and these patterns were observed both in male and female caregivers.
With respect to caregiver’s physical functioning, a decrease was observed 3 months after baseline. Different patterns emerged for male and female caregivers, which was also illus- trated in Figure 2. No significant change was observed in male caregivers, whereas female caregivers reported a poorer physical functioning over time.
Although no gender effect on physical functioning over time was observed, there appeared to be an interaction effect between time and gender (F(2,294) = 5.32, p c .01). For mental functioning, a significant improvement over time was observed (F(2, 294) = 10.42, p c .0001), and this was observed both for female and male caregivers. Compared to male caregivers, female caregivers reported a significant poorer mental functioning at baseline, and continued to do so over time (F( 1, 146) = 4.23, p c .05). Also with respect to social functioning over time, a significant improvement was found (78.4 to 85.1; p c .OOl>. Additional analyses revealed that no gender effects or interaction effects between time and gender existed regarding changes over time in social functioning (F( 1, 146) = 2.05 and F(2,292) = 1.5 1, respectively).
In a random Dutch population sample ( N = 1043), the values of physical, mental and social functioning for males were 84.5,79.4 and 88.4, respectively; for females, these were 80.7,75.7 and 86.1 (Van der Zee and Sanderman, 1994). With respect to physical function- ing, no substantial difference between observed mean score and reference score was found for male caregivers, but for female caregivers the mean baseline physical functioning score was notably higher in the current study. Scores on mental and social functioning of both
Figure 2 Physical, mental and social health dimensions of male and female caregivers of newly diagnosed colorectal cancer patients over time.
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CANCER CAREGIVER’S HEALTH 48 1
men and women were notably lower in the current sample compared to those found in the reference study.
Prediction of Changes in Three Dimensions of Caregiver’s Health
Results of regression analyses as displayed in Table 4 show the predictors of change in caregiver’s health indices over 6 months after baseline. Here, we tested the effect of changes in patient and care characteristics over time on changes in health outcomes, adjusting for baseline data.
With respect to physical functioning, initial score on physical functioning was evidently the strongest predictor of physical functioning at 6 months after baseline. Male caregivers, those of a lower age and with a higher income appeared to report a significantly better physical functioning over time than female caregivers, those of a higher age and those with a lower income. Total explained variance of physical functioning was high, i.e. 73%, and did not improve significantly if the changes in patient and/or care characteristics were added to the model.
With respect to mental functioning, initial score on mental functioning and gender showed to be associated with mental functioning 6 months after baseline, explaining a total of 35%. Care characteristics as well as changes in these factors appeared to contribute another 9% and 6% respectively to the explained variance of changes in mental functioning. Both negative and positive caregiver experiences, i.e. disrupted schedule and care-derived
Table 4 Hierarchical linear regression analyses predicting three dimensions of caregiver’s health (i.e. physical, mental and social functioning) over a 6 month-period by (changes in) patient and care characteristics ( N = 148)
~~
Caregiver’s health outcomes at Tz
Physicalfunctioning Mentulfunctioning Socialfunctioning
B P 13
Step 1. Caregiver background char. (To) Initial health status .73*** .56*** .38*** Gender (0 =male; 1 = female) -.17*** -.20** -.12+ Age -.12* -.08 -.04 Income .13** -.02 .08 RZ .72 .35 .I5 Step 2. Patient and care char. (To) Level of patient’s dependency .o 1 -.06 -.19* Number of care tasks .03 .08 .02 Caregiver experiences
Disrupted schedule .03 -.18’ -.02 Care-derived self-esteem .05 .26*** .16*
Change in R2 .01 .09 .03 Step 3. Changes in cure situation (Tu-T2):
Caregiver experiences Level of patient’s dependency -.07 .15+ -.43***
Disrupted schedule .03 -.21* -.I1 Care-derived self-esteem .02 -.08 -.I0
Change in R2 .01 .06 .I9 Total explained variance 73% 49% 37%
Noit: fi=Finaladjustedweights. ‘ p < . I O ; * p < . O 5 : * * p < . O l ; * * * p < . ~ 1
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.._. 85 ..... Low income
I
TO T i T2
Figure 3 Caregiver’s physical functioning patterns according to gender and income. t--. men; ........... women.
self-esteem, contributed to improvement in mental functioning. In particular, a decreasing perceived impact on schedule over time appeared to have an uplifting effect on mental functioning 6 months thereafter.
Compared to physical and mental functioning, social functioning showed to be less affected by the initial value. While baseline patient and care characteristics did contribute slightly to social functioning, changes in patient’s dependency added 19% to social func- tioning. Decreasing levels of patient’s dependency appeared to improve caregiver’s social functioning 6 months thereafter.
Gender-Specific Associations of Caregiver’s Health Patterns
With respect to physical functioning, gender was significantly associated with physical functioning after adjustment for the other caregiver, patient and care variables (p= -. 17); i.e. female caregivers reported a worse physical functioning than male caregivers, regardless caregiver’s background characteristics, patient’s dependency, number of tasks or caregiver experiences. A significant interaction effect was observed between gender and income (p= .40), which is illustrated in Figure 3. Female caregivers with a low income reported a poorer physical functioning over time, while for male caregivers the role of income showed to be of less importance in predicting patterns of physical functioning.
With respect to mental functioning, the pattern over time was approximately the same for male and female caregivers in general. However, a gender effect (p= -.20 ) and two gender interaction effects were found, namely a gender-income (p= -.53 ) and a gender- change in self-esteem effect (p=-.31 ). Female caregivers reported on average a poorer mental functioning than male caregivers. A negative gender-income interaction effect on mental functioning over time indicated that female caregivers with a low income reported a worse mental functioning than male caregivers with a low income. Moreover, while mental functioning of male caregivers with a low income improved 6 months after baseline, no relevant change was observed in female caregivers with a low income (Figure 4). Also a negative interaction effect of the interaction between gender and change in self-esteem on mental functioning was found.
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85 -
80 -
75 -
70 -
65 -
483
....................................
.. ..................................................... Lower mpact on s d esteem wer time
H i # m mpact on set nsIeem wer time ..‘ .--
85 1 80
75
70
65 .... . .... ...
%_ Low income
60 4 I
TO T i T2
Figure 4 Caregiver’s mental health patterns according to gender and income. -men; ............ women.
Male caregivers who were able to derive more self-esteem over time showed improve- ment in mental functioning. Female caregivers, however, who were able to derive more self-esteem over time did not show better mental functioning over time (Figure 5).
No gender or gender interaction effects could be observed for social functioning. Thus, the previously reported relations as found in this study were similar for male and female caregivers.
DISCUSSION
In this study, the patterns and determinants of the physical, mental and social health dimen- sions of caregivers of patients with newly diagnosed colorectal cancer were studied over a
60 TO T1 T2
Figure 5 Caregiver’s mental health patterns according 10 gender and change in impact on self-esteem. - men; ............ women.
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6-month period after diagnosis. With respect to caregiver’s physical functioning patterns, a decrease was observed 3 months after baseline. And this pattern was observed in female caregivers, but not in male caregivers. With respect to mental and social functioning in general, a significant improvement over time was observed both in male and female care- givers. Studies on physical and social functioning over time of caregivers of cancer patients were not available. However, studies on mental health patterns of cancer caregivers also did report improvements over time (Hoskins et al., 1996; Northouse and Swain, 1987; Oberst and Scott, 1988).
The current study also revealed that changes in physical functioning were predominantly predicted by the initial physical status and caregiver’s background characteristics, whereas changes in mental and social functioning were largely predicted by initial states and patient and care characteristics. Changes in mental functioning were also predicted by caregiver experiences and changes in social functioning were also predicted predominantly by change in patient’s dependency.
Compared to reference values of a random Dutch population sample (Van der Zee and Sanderman, 1994), the mean baseline score of physical functioning of the female caregivers was substantially higher and the baseline scores of both mental and social functioning were lower. These findings suggest that change could mean that caregivers returned to the same levels of functioning they had at an earlier point in their caregiving career, e.g. before the onset of patient’s complaints. This seems to be particularly valid for physical functioning, since changes in physical functioning were observed to be independent of the care charac- teristics and experiences.
Health deterioration may be attributable to the stressors of caregiving, while health improvement may result from a decrease of caregiving stressors or adaptation of caregivers over time. Since the level of patient’s dependency decreased over time and this showed to contribute to caregiver’s social functioning over time, improvement of social functioning may indeed be attributable to changes in the caregiving situation. Since negative caregiver experiences appeared to be less burdensome over time and showed to predict mental func- tioning patterns, psychological adaptation is likely to occur. Moreover, apart from negative caregiver experiences, positive caregiver experiences (i.e. perceived impact on self- esteem) seemed to play an important role. This may suggest that satisfaction was derived from meeting a difficult challenge and therefore caregivers might have benefitted from the experience of giving care to their partner, leading to health improvement.
A major conclusion is that male and female caregivers should be regarded as distinct groups, since different predictors of health outcomes were observed in male and female caregivers. This is in concordance with other research (Rose-Rego et al., 1998). While in male caregivers, physical functioning remained unchanged and mental functioning im- proved over time, less favorable patterns were observed in female caregivers, particularly in those with a low income. Also, caregivers who were able to derive more self-esteem from caregiving over time, mental functioning improved in male caregivers, while this was not observed in female caregivers. No gender differences could be observed in social func- tioning patterns. Differences in coping strategies or adaptation of male and female caregiv- ers may be the underlying mechanism. Unfortunately, these concepts were not included in this study.
One methodological issue can be raised about an apparent contrasting finding concerning gender-specific changes in mental functioning. Although we found no differential effect for men and women in mental functioning over time (Table 3), mental functioning seems to be affected by gender (Table 4). The mental functioning of male caregivers significantly
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improved over time, while in female caregivers the mental functioning less obviously improved (see Table 3). Overall, the interactive effect of time and gender was not detected as significant, which may be due by the relatively small number of persons in the male group (i.e. n = 54). Also, it could be that the separate time and gender effects were much larger compared to the interactive effect, and therefore the time-gender effect became less important. Moreover, in male caregivers improvement in mental functioning was observed for all waves, while in female caregivers a large improvement in mental functioning was observed between To and T,, but not between T, and T,. Since both groups showed an improvement over time, an overall time-gender effect may have turned out to be non-significant.
Apart from gender, age and income had a different impact on caregiver’s health. Higher age and lower income were associated with poorer functioning, particularly in the phys- ical dimension. Moreover, improvement of functioning was associated with a lower age and a higher income. As people age, their general functioning, and in particular their physical functioning, is expected to decline (Van der Zee and Sanderman, 1994). In a longitudinal study of depression among family members of Alzheimer’s disease (Schulz and Williamson, 1991), individuals who were more concerned about the adequacy of their income reported higher levels of depression, and this was especially observed early in the caregiving process. In a study on the costs of care of family members caring for cancer patients at home, Stornmel, Given and Given (1993) concluded that costs are usually underestimated by others. Attention to those with a relatively low income in particular is warranted.
Finally, consistent with the cognitive stress theory, is the finding that contextual (i.e. patient’s dependency) and appraisal-related factors (i.e. caregiver experiences) appeared to play a major role in explaining changes in caregiver’s functioning (i.e. mental functioning in particular, and social functioning to a smaller degree). However, as we may presume from the cognitive stress theory, also other appraisal-related factors, such as caregiver’s coping and social support play an important role in the caregiving’s process. These factors were not included in the current study. Moreover, only direct effects have been examined, while moderating effects may also occur. Within this respect concerns the issue of labelling and operationalisation of caregiver experiences. Making a methodological distinction between stressors, appraisal-related factors and health outcomes is difficult. For example, disrupted schedule may be a stressor rather than an indicator of appraisal-related factors, and care-derived self-esteem may strongly overlap with mental functioning. Although it has been stressed that caregiver’s disrupted schedule and care-derived self-esteem are personal experiences of caregiving (Given et al., 1992), more research is needed to explicitly examine the role of these concepts in the caregiving process.
Although this study incorporated a number of strengths including a longitudinal design, use of multiple outcome measures, gender-based subgroup analyses, adjustment for initial caregiver’s functioning, and adjustment for age, gender and income, it is necessary to acknowledge some limitations. One of these is the generalizability of the findings of this study. As was expected in a sample of caregivers of newly diagnosed colorectal cancer patients, overall health improvements rather than worsening health states were observed. However, the selection of this specific sample may have overestimated this effect. Although the drop-out rates were fairly acceptable, selection-bias may have occurred, since patient’s dependency in those who dropped out was significantly higher at baseline than patients who were followed for 6 months ( p < .05). It may be possible that only the most seriously ill or problematic patients with cancer produce health decrements in
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their caregivers, and therefore, others who provide only marginal care may dilute health consequences to those with the greatest care demands. And, caregivers in the current study may not have been representative for the caregivers of newly diagnosed colorectal cancer patients. Subjects who were included may have experienced minimal burden of caregiving, as their partners (patients) had a relatively good prognosis. Thus, we might have included only the most healthy caregivers and this selection bias could have led to an underes- timation of the observed relationships between stressors, caregiver experiences and health outcomes.
IMPLICATIONS FOR FURTHER RESEARCH
This study shows that - apart from making a distinction of gender - examining health consequences of caregiving may be more likely to detect differences when multidimen- sional assessment strategies are used. The impact of contextual and appraisal-related factors like patient’s dependency, care demands and experiences on health outcomes may be underestimated when research restricts its scope to a single generic health outcome. This is also in accordance with other research findings on stress and caregiving (Aneshensel, Rutter and Lachenbruch, 1991; Shaw, Patterson, Semple, Ho, Irwin, Haugher and Grant, 1997; Thoits, 1995). Schulz and colleagues (Schulz et al., 1995; Schulz, Vistainer and Williamson, 1990) proposed that physical health effects of caregiving may be particularly difficult to document (relatively to mental and social health effects) because physical health effects may be only becoming evident for some time after the onset of caregiving. Given our focus on the first 6 months after baseline of newly diagnosed cancer patients, we could not consider the impact of caregiving that typically may develop after several years of caregiving. This suggests the need for longitudinal studies with more extended periods of follow-up.
Future research might also include additional factors to determine the (mediating and/or moderating) role within the caregiving process. Previous studies have recognized the important role of the quality of the relation (Manne and Zautra, 1990; Triemstra, Van der Ploeg, Smit and Rosendaal, 1999), social support (Schulz and Williamson, 199 l), personality characteristics (Given, Stommel, Given, Osuch, Kurtz and Kurtz, 1993; Hooker, Monahan, Shifren and Hutchinson, 1992; Kurtz et al., 1997; Skaff, Pearlin and Mullan, 1996), and coping strategies (Lawton et al., 1989) which may influence caregiving outcomes.
This study addressed caregiver’s physical, mental or social health consequences following patients with newly diagnosed colorectal cancer from the period of two weeks before hos- pital admission, to 3 and 6 months after baseline. Although caregiving may be burdensome over time for some caregivers, our data suggest that giving care may be perceived positive as well, leading to health improvements. Moreover, the findings of this study underline the importance of making a distinction in gender and of studying caregiver outcomes by using multidimensional assessments.
Acknowledgements
This study was supported by the Dutch Cancer Society (AMC 95-1 138). We would like to thank all the patients and partners who took part in the study and the physicians and co-workers in the co-operating hospitals for the recruitment of patients.
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