Dimension-specific burden of caregiving among partners of rheumatoid arthritis patients

C. E. Jacobi1,2, B. van den Berg3,4, H. C. Boshuizen3, I. Rupp2,3, H. J. Dinant5,6 and G. A. M. van den Bos2,3

1Department of Medical Decision Making, Leiden University Medical Centre, Leiden, 2Department of Social Medicine, Academic Medical Centre, University of Amsterdam, Amsterdam, 3National Institute of Public Health and the Environment, Bilthoven, 4Department of Health Policy and Management and Institute for Medical Technology Assessment, Erasmus Medical Centre, Rotterdam, 5Jan van Breemen Institute, Centre for Rheumatology and Rehabilitation, Amsterdam and 6Department of Clinical Immunology and Rheumatology, Academic Medical Centre, University of Amsterdam, The Netherlands.

Correspondence to: C. E. Jacobi, Department of Medical Decision Making (J10-R), Leiden University Medical Centre, P.O. Box 9600, 2300 RC Leiden, The Netherlands. E-mail: c.e.jacobi{at}lumc.nl


    Abstract
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
Objectives. To assess subjective caregiver burden among partners of rheumatoid arthritis (RA) patients and to identify partner and patient variables and objective caregiver burden related to subjective caregiver burden.

Methods. In 2001, 134 patients diagnosed with RA and their caregiving partners participated in a postal questionnaire survey. Information was gathered on age, gender and health problems of patient and partner, disease duration of the patient, objective caregiver burden and subjective caregiver burden of the partner (using the multidimensional Caregiver Reaction Assessment). Correlation coefficients were computed between the subjective caregiver burden dimensions. Multivariate analyses were performed to identify variables that explained the variation in subjective burden.

Results. Partners of RA patients derived, on average, a high level of self-esteem from giving care. Negative subjective caregiver burden was to a large degree caused by a disrupted schedule and to a smaller degree by a lack of family support, financial problems and loss of physical strength. Problems of the partner with mobility or with pain/discomfort and problems of the patient with self-care activities and activities of daily life had the largest impact on negative levels of subjective caregiver burden.

Conclusions. Health parameters of the patient and partner have a considerable predictive value for the development of high levels of subjective burden in partners of RA patients. Support strategies should be developed for partners of RA patients, and should focus especially on reducing the burden caused by a disrupted schedule, and simultaneously on increasing the focus of caregivers on the positive aspects of caregiving.

KEY WORDS: Rheumatoid arthritis, Partners, Caregiver burden, Impact of caregiving, Informal care, Multidimensional burden of caregiving.


    Introduction
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
Rheumatoid arthritis (RA) is a chronic, inflammatory disease that predominantly affects the joints of patients. It is a progressive disease, characterized by immune-driven chronic inflammation and a variable course involving exacerbations and remissions of disease activity. The progressive character of RA causes irreversible joint damage that results in minor to severe disability and leads to consequences for physical, social and psychological functioning [1]. Follow-up studies among RA patients showed that after 10–20 yr of follow-up about 20% of the patients had no or minor disabilities, most of the patients were moderately disabled, and about 10% of the patients suffered from severe disablement [25].

The physical impairments and disabilities of patients with RA often impede the performance of activities of daily living (ADL), resulting in the use of a wide variety of health-care services [6]. Additionally, many RA patients need care and help at home, which is mostly provided by informal caregivers. The slow, progressive nature of the disease creates long-term dependency on family and friends. Spouses or partners, in particular, are expected to bear a large proportion of the burden of caregiving [7].

The concept of caregiver burden has been investigated widely, both in general and among caregivers of specific groups of patients. Studies in this field reveal that caring for an individual with disability is burdensome and stressful, which contributes to lower quality of life, psychiatric morbidity and early mortality of the caregiver [8].

Previous studies have investigated variables that could explain or predict the burden as perceived by caregivers. It has been shown that caregiver burden can be explained or predicted by three types of factor: patient characteristics, caregiver characteristics and objective caregiver burden, e.g. the number of care tasks to perform [9]. The relation between caregiver burden and these factors has been studied for caregivers of mentally ill patients [10], stroke patients [11], cancer patients [12] and RA patients [1315]. The association between caregivers’ age and caregiver burden yielded mixed findings. Some studies found that younger caregivers experienced a greater burden than older caregivers [10, 11], and in others no association between caregivers’ age and caregiver burden could be determined [10, 11]. Regarding caregivers’ gender, educational level and family income, no relation with caregiver burden was shown for informal caregivers of mental patients and stroke patients [10, 11], while among informal caregivers of cancer patients high caregiver burden was associated with low family income [12]. Furthermore, higher caregiver burden was associated with decreased physical health of the patients, caregivers’ depression, and the amount of care provided [1012]. It was found that caregiver burden was lower if professional support was received [10].

Regarding caregiver burden in RA, a greater caregiver burden was associated with worse mental health of both the patient and the caregiver, and lower health status of the patient [13], with worse expectancies of arthritis-related symptom control of the patient [14], with worse caregiver’s physical health and with higher objective caregiver burden [15].

These studies among caregivers of RA patients investigated an overall level of caregiver burden and did not differentiate among the various dimensions of caregiver burden. Because of the need for a multidimensional approach to caregiver burden, the Caregiver Reaction Assessment (CRA) has been developed [16] to assess caregiver burden in five dimensions, including both positive and negative burdens of caregiving. This multidimensional approach gives the opportunity to plan specific intervention strategies for caregivers.

In this study, we assessed caregiver burden among partners of patients with RA, using the CRA, and we determined patient characteristics, partner characteristics and objective burden variables that explain subjective caregiver burden, to find markers to identify partners who are vulnerable to developing substantial subjective burden. The results of this study could be used to develop specific intervention strategies for partners of patients with RA in order to prevent or decrease the negative burden of caregiving.


    Patients and methods
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
Study population
The present study was performed in 2001 and was the third follow-up of a longitudinal study on health and health-care among patients with RA that started in 1997 among 882 patients. The patients were selected from the register of a large rheumatology out-patient clinic in Amsterdam and five associated out-patient clinics. Inclusion criteria were at least 16 yr of age and meeting the 1987 revised American College of Rheumatology (ACR) criteria [17]. The medical ethical committee of the Slotervaart Hospital Amsterdam approved the study design. All patients signed informed consent.

For the present study, 683 patients were asked whether they received informal care from their partner or others. If the patient received informal care from their partner, the patient and his or her partner were asked to participate in the present study. Patients who were lost to follow-up, from 1997 to 2001, because of death or relocation (n = 41), were significantly older (P = 0.001) than participants, but no differences were found regarding gender or educational level. No differences were found between patients who withdrew consent in this period (n = 158) and the follow-up respondents (n = 683) regarding age, gender or educational level.

Data collection
Data were collected by two self-report questionnaires, one for the partner and one for the patient. Information on disease duration was abstracted from the patients’ files.

Partner variables
Sociodemographic characteristics
Sociodemographic characteristics were age and gender.

Health status
Health was assessed with the EuroQoL questionnaire [18, 19]. This questionnaire consists of five dimensions of health (mobility, self-care activities, ADL, pain/discomfort, and anxiety/depression), each with three answers: ‘no problems’, ‘moderate problems’ and ‘extreme problems’. Because of low numbers in the ‘extreme problems’ category, the answering categories of each of the dimensions were recoded for analyses into 0 (no problems) and 1 (moderate or extreme problems).

Patient variables
Sociodemographic characteristics and health status
The assessment of the sociodemographic characteristics and health status of the patient was identical to that for the partner.

Disease duration
The disease duration of the patient was abstracted from the patient’s files.

Professional home care
Patients were asked whether they received professional home care (yes/no), and whether they were on a waiting list for professional home care (yes/no).

Objective caregiver burden
The objective caregiver burden consisted of the tasks required to care for the patient (care tasks, home tasks, help tasks), time spend on these tasks, care duration and the number of care days a week.

Care tasks comprised ‘help with personal care’, ‘help with toilet care’, ‘help with moving indoors’ and ‘help with eating/drinking’. Home tasks included ‘fixing food or drinks’, ‘house cleaning’, ‘doing laundry/ironing/sewing’ and ‘shopping’. Help tasks were ‘help with moving outdoors’, ‘accompanying or helping with visits or day trips’, ‘accompanying or helping with health-care visits’, ‘taking care of adaptations in the home’, and ‘financial business’. Partners were asked whether they performed any care tasks (yes/no), any home tasks (yes/no) or any help tasks (yes/no) and how much time they spent on these tasks. Time per type of task was summed to compute a total time score. Care tasks were determined in minutes per day, and home tasks and help tasks in hours per day.

Care duration was defined as the total time in years for which the partner gave care to the patient. Care days referred to the number of days per week on which the partner performed care tasks, home tasks or help tasks.

Subjective caregiver burden
Subjective caregiver burden was assessed with the Dutch version of the CRA [16, 20]. The CRA was developed and validated in the USA among caregivers of persons with all types of chronic physical and mental impairments [16], and the Dutch version was also found to be valid among caregivers of colorectal cancer patients [20]. The CRA consists of 24 items on five dimensions that assess both the positive (‘care-derived self-esteem’) and the negative (‘lack of family support’, ‘financial problems’, ‘disrupted schedule’ and ‘loss of physical strength’) burden of caregiving, as described in Table 1. Each item is rated on a five-point scale, ranging from ‘strongly disagree’ to ‘strongly agree’. For each dimension, a total score was computed as the average of the item scores, ranging from 1.0 to 5.0. A score of 1.0 represents ‘no derived self-esteem’ on the positive dimension, and ‘no burden’ on the negative dimensions.


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TABLE 1. Dimensions of the Caregiver Reaction Assessment (CRA) [16]

 
Statistics
All analyses were performed using SPSS 10.0 for Windows (SPSS, Chicago, IL, USA). Frequency tables and descriptive statistics were assessed for all variables. To determine the relation between each of the five dimensions of subjective caregiver burden, the Spearman correlation statistic ({rho}) was computed. We defined correlations of {rho} >= 0.4 as being relevant for reporting in the text.

To be able to interpret the absolute outcome values of the CRA, these values were compared with those of informal caregivers of patients with other chronic illnesses, namely cancer patients [21] and patients with dementia [22]. These other CRA values were abstracted from the literature.

To identify the effect of the variables mentioned above on subjective caregiver burden, a multivariate linear regression model was built for each of the five dimensions of subjective caregiver burden. By stepwise regression, partner variables, patient variables and objective caregiver burden variables were selected as the independent variables. Variables were included in the model if their contribution to the model was statistically significant (if P < 0.05). A maximum of six variables was accepted in each model. The effect sizes are expressed as the beta (ß) value, i.e. the regression coefficient of the linear model, and the 95% confidence interval (CI).


    Results
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
Study population
Of the 683 eligible patients, 33 were lost because of relocation to an unknown address (n = 12) and death (n = 21). Of the remaining 650 patients, 242 (37.2%) received informal care from their partner. Of these caregiving partners, 134 (55.4%) responded. No significant differences regarding age and disease duration were found between patients for whom the partner had responded and patients for whom the partner had not responded. Partners of female patients were more likely to respond than partners of male patients ({chi}2 = 39.3, P < 0.001). Patients for whom the partner had responded significantly more often had problems with mobility ({chi}2 = 32.6, P < 0.001), self-care activities ({chi}2 = 27.3, P < 0.001) and ADL ({chi}2 = 31.9, P < 0.001), and suffered more often from pain/discomfort ({chi}2 = 18.2, P < 0.001) than patients for whom the partner had not responded. No differences could be found for anxiety/depression between these two patient groups ({chi}2 = 2.9, P = 0.089).

Partner and patient variables
The characteristics of patients and their partners are shown in Table 2. The mean age of the patients (n = 134) was 61.9 yr (range 28.1–84.9; S.D. 13.0) and that of their partners was 62.7 yr (range 32.5–86.8; S.D. 12.9). Women constituted 84.3% of the patients (n = 113).


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TABLE 2. Characteristics of patients with RA and their caregiving partners (n = 134)

 
The mean disease duration of the patients was 12.7 yr (range 3.0–59.8; S.D. 9.0). Only three patients (2.3%) did not suffer from pain/discomfort; 93 (69.9%) did not suffer from anxiety/depression. Regarding the other EuroQoL dimensions, no problems were reported in mobility, ADL and self-care activities by 15 (11.2%), 20 (14.9%) and 64 (48.1%) patients respectively. On these five dimensions of health, partners were more healthy than patients. Of the partners, 69 (53.1%) did not suffer from pain/discomfort, and 103 (78.0%) did not suffer from anxiety/depression. No problems with ADL, mobility and self-care activities were reported by 93 (71.0%), 95 (71.4%) and 120 (91.6%) partners respectively. Regarding professional home care, 34 patients (25.6%) received home care and nine patients (6.9%) were on a waiting list for this service.

Objective caregiver burden
Objective caregiver burden consisted of care tasks for 40.3% of the partners (n = 54), of home tasks for 97.0% (n = 130) and of help tasks for 77.6% (n = 104) (Table 3). Care tasks took on average 41.78 min a day to accomplish. For home tasks and help tasks, on average 2.58 h (S.D. 2.45) and 0.75 h (S.D. 0.83) a day were needed respectively. Partners were giving care over an average of 11.4 yr (S.D. 8.7) and almost 6 days a week (S.D. 2.06).


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TABLE 3. Objective caregiver burden among partners of RA patients (n = 134)

 
Subjective caregiver burden
The score on the positive dimension of caregiver burden, self-esteem, was on average 4.21 (range 1.6–5.0; S.D. 0.66) (Table 4). The mean scores on the negative burden dimensions were 3.28 (range 1.0–5.0; S.D. 0.53) for a disrupted schedule, 2.50 (range 1.0–5.0; S.D. 1.07) for lack of family support, 2.36 (range 1.0–5.0; S.D. 1.21) for financial problems, and 2.27 (range 1.0–4.5; S.D. 1.13) for the loss of physical strength.


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TABLE 4. Subjective caregiver burden (CRA) among partners of RA patients (n = 134), partners of patients with colorectal cancer (n = 148) [21] and informal caregivers of patients with dementia (n = 93) [22]; data are mean (95% CI)

 
Compared with the burden levels of the partners of patients with colorectal cancer, partners of RA patients derived a similar level of self-esteem, but statistically significantly higher levels on all four negative burden dimensions (Table 4). In comparison with caregivers of patients with dementia, partners in our study experienced statistically significantly higher levels of self-esteem and loss of physical strength, but a similar level of burden as a result of disrupted schedule.

Correlation between subjective caregiver burden dimensions
Some correlations between subjective caregiver burden and partner variables, patient variables and objective caregiver burden variables were higher than 0.4. Self-esteem was negatively correlated with lack of family support (r = –0.425) and loss of physical strength (r = –0.507). Lack of family support was positively correlated with financial problems (r = 0.405) and with loss of physical strength (r = 0.622), and financial problems and loss of physical strength were positively correlated (r = 0.588) (data not shown).

Impact of partner, patient and objective burden variables on subjective caregiver burden
The amount of variance explained (R2) by the multivariate regression models varied from 21.5% for self-esteem to 49.5% for loss of physical strength (Table 5). Giving care to a patient with RA decreased the self-esteem of the partner if the partner had problems with ADL (ß = –0.534; 95% CI –0.770, –0.297) and if the patient received home care (ß = –0.330; 95% CI –0.575, –0.086) (Table 5).


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TABLE 5. Impact of partner and patient variables and objective caregiver burden on the subjective caregiver burden among caregiving partners (n = 134) of patients with RA (multivariate stepwise regression)

 
Lack of family support caused a greater burden if the partner had problems with mobility (ß = 0.803; 95% CI 0.402, 1.204), if the patient had problems with self-care activities = 0.709; 95% CI 0.334, 1.085), if the partner performed help tasks (ß = 0.542; 95% CI 0.030, 1.053), and as the number of care days a week was higher (ß = 0.150; 95% CI 0.057, 0.242). This burden was lower if more time was spend on home tasks (ß = –0.115; 95% CI 0.192, –0.038).

Financial problems resulted in a greater subjective burden if the partner reported problems with mobility (ß = 1.012; 95% CI 0.524, 1.500) and if the patient had problems with self-care activities (ß = 0.755; 95% 0.336, 1.174). The scores on this dimension, however, decreased as the age of the patient increased (ß = –0.026; 95% –0.043, –0.010).

The schedule of the partner was more disrupted with lower age of the patient (ß = –0.008; 95% –0.015, –0.001), if the partner performed care tasks (ß = 0.310; 95% CI 0.122, 0.497) and help tasks (ß = 0.479; 95% CI 0.210, 0.748) and with increasing number of care days per week (ß = 0.083; 95% CI 0.037, 0.130).

Loss of physical strength of the caregiver was higher if the partner had problems with mobility (ß = 0.835; 95% CI 0.403, 1.267) or suffered from pain/discomfort (ß = 0.722; 95% CI 0.335, 1.110), if the patient had problems with self-care activities (ß = 0.474; 95% CI 0.127, 0.820) or ADL (ß = 0.596; 95% CI 0.068, 1.124), and if the partner performed help tasks (ß = 0.516; 95% CI 0.032, 1.000).


    Discussion
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 
We investigated the extent of subjective burden among partners of patients with RA on various dimensions. We found that caregiver burden is common among partners of patients with RA, and we identified partner and patient variables and objective caregiver burden variables that explained the variation in subjective caregiver burden.

Partners derived, on average, high self-esteem as a result of giving care. The dimension ‘self-esteem’ measures the extent to which caregiving imparts self-esteem, which implies that partners found, to a large extent, positive aspects in providing care. Negative aspects of subjective caregiver burden were to a large degree caused by a disrupted schedule and to a smaller degree by a lack of family support, financial problems and loss of physical strength. Given the results of the correlation analyses, patients who reported higher self-esteem perceived fewer financial problems and less loss of physical strength.

In comparison with caregivers of patients with dementia [22], partners in our study experienced higher levels of self-esteem and loss of physical strength, but a similar level of burden as a result of disrupted schedule. The relatively high levels of burden on the ‘loss of physical strength’ dimension among partners of RA patients could be caused by the way caregiver and patient were related. Our study focused on the partners of patients with RA, whereas in the study among caregivers of dementia patients the caregivers were related to the patient in various ways, such as partner, adult offspring, other family member and friend, and only 24% lived with the patient. Not living with the patient might result in less loss of physical strength, which is in concordance with previous results that caregivers who live with the patient experience a greater burden than caregivers who do not [23]. Nijboer et al. [21] studied burden levels of caregiving partners of colorectal cancer patients up to 6 months after discharge of the patient from hospital. Compared with the burden levels of the partners of these cancer patients, partners of RA patients derived a similar level of self-esteem but higher levels on all four negative burden dimensions. Partners in our study provided care for a longer period than the partners of the cancer patients (i.e. 11.4 yr vs a maximum of 6 months). Negative experiences resulting from giving care may increase as the duration of care provision increases.

We found that health variables of partner and patient, as measured with the EuroQoL questionnaire [19], and objective burden variables could explain a considerable part of the variance (21.5–49.5%) of all five dimensions of subjective caregiver burden, as assessed with the CRA. Problems of the patient with self-care activities and ADL and problems of the partner with mobility or pain/discomfort had a very large impact on negative levels of subjective caregiver burden. It is to be expected, therefore, that these health parameters of both patient and partner will have a considerable predictive value for the development of high levels of subjective caregiver burden in partners of RA patients. These findings are in concordance with the results of Chenier [24], who has shown in a review that decreased functional abilities of the patient was positively correlated with caregiver burden. Moreover, in our study group, more than 20% of the partners suffered from moderate or extreme anxiety/depression and almost 50% suffered from moderate or extreme pain/discomfort, which might, at least partly, indicate the straining effect of providing long-term care.

Age and gender of the partner had no influence on subjective caregiver burden. Previously, it was shown that younger caregivers experience greater burden than older caregivers [25] and that women exhibit greater burden than men [2527]. Our results, however, could not confirm these findings. It is notable that we had relatively more male caregivers in our study than the other studies had.

In general, studies investigating caregiver burden among partners, adult children, other relatives and friends, each caring for elderly or chronically ill patients, have shown considerable burden levels in these caregivers. If we apply our findings to the general Dutch population [28], informal caregiving would concern almost 80 000 informal caregivers in the Netherlands, for RA only. It is expected that caregiver burden will increase significantly in the years to come, due to the ageing of the population, the ensuing rise of chronic patients and the shortage of personnel in nursing and caring professions in The Netherlands [29].

The shift of health-care to the ambulatory care setting has resulted in a dramatic increase in the burden placed on a patient’s family. Despite this, caregiver burden is greatly underidentified by, for instance, primary care physicians [30]. Although researchers have not reached consensus on the effect of caregiving on the caregiver’s long-term health [31], it was shown that informal caregivers who report a burden are at greater risk of adverse health outcomes [8, 1013, 15]. Family physicians should, therefore, be aware of negative signals from informal caregivers to prevent them becoming patients themselves. As an example of an initiative to support informal caregivers, several years ago a new organization was founded in The Netherlands as a support group for informal caregivers [32]. This organization [Landelijke Organisatie van Mantelzorgers (LOT)] was founded to support informal caregivers and help them when problems arise, exist or increase.

Some remarks on our results are necessary. First, because most of the caregiving partners in our study were male (82.1%) and some studies have shown that female caregivers perceive greater burden [1012], our results might present an underestimation of the caregiver burden. Secondly, many caregiving partners did not respond, while the patients they cared for did respond. On the one hand, these partners might have perceived high levels of caregiver burden and, hence, could not find the time or strength to participate in the questionnaire survey. This might have led to underestimation in our results. On the other hand, these non-responding partners might have perceived caregiving to the patient as self-evident, which might have led to overestimation in our results. Thirdly, the CRA provides no overall burden score, which makes it difficult to reach a conclusion regarding overall caregiver burden. Moreover, no cut-off point for substantial burden is available for the CRA, which makes it difficult to distinguish between groups of informal caregivers with and without substantial burden. Fourthly, the RA patients included in this study might have suffered from comorbidity, as many patients with RA report comorbidity [3335]. We are, therefore, unable to conclude that the levels of caregiver burden observed among the partners of these RA patients are solely attributable to RA and not also to other illnesses. Fifthly, previous studies on informal care in RA have shown that various psychological factors, such as self-efficacy, coping and feelings of optimism and pessimism, influence caregiver burden [14, 15]. In this study we did not elaborate on these psychological factors, but focused on more objective variables in relation to subjective caregiver burden.

In conclusion, partners found, to a large extent, positive aspects of providing care to the RA patient. Negative aspects of subjective caregiver burden were predominantly caused by a disrupted schedule and to a smaller degree by a lack of family support, financial problems and loss of physical strength. In addition, partners who derived greater self-esteem from caregiving perceived fewer financial problems and less loss of physical strength. Problems of RA patients in self-care or ADL are to a large extent related to higher negative levels of caregiver burden among partners.

The results of this study could be used for identifying partners at risk of high negative burden and may lead to the development of support strategies to prevent or decrease high levels of negative caregiver burden and to increase the focus of caregivers on the positive aspects of caregiving. Preventing or decreasing high levels of negative caregiver burden is necessary, because caregiver burden contributes to adverse health outcomes [8, 1013, 15]. Changing the focus of caregivers towards positive aspects of caregiving results in lower levels of depression, lower levels of negative caregiver burden and better self-assessed health in the caregiver [36]. Further research may help to establish evidence-based interventions by developing either specific support strategies for caregiving partners of patients with RA or specific care programmes for RA patients. Such interventions may strengthen the sustainable care provided at home.


    Acknowledgments
 
This study was supported financially by the Dutch Arthritis Association (het Nationaal Reumafonds) and the Netherlands Organization for Health Research and Development—Medical Sciences (ZON-MW; grants 940-32-002 and 945-10-044).

Conflict of interest

The authors have declared no conflicts of interest.


    References
 Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 References
 

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Submitted 20 December 2002; Accepted 19 March 2003