Pre-dialysis patients' perceived autonomy, self-esteem and labor participation: associations with illness perceptions and treatment perceptions. A cross-sectional study

Chronic renal failure, also referred to as end-stage renal disease (ESRD; chronic kidney disease (CKD) stage V), is a permanent condition which requires renal replacement therapy (peritoneal dialysis, haemodialysis or transplantation) to maintain life. At the end of 2005, approximately 1,9 million people were receiving renal replacement therapy worldwide [1]. In January 2006, 12,038 people in the Netherlands received renal replacement therapy (737 people per million Dutch residents) [2]. ESRD is associated with specific disease and treatment aspects. Patients with ESRD often experience physical symptoms such as fatigue, pain, cramps and itching [3]. Furthermore, patients are extremely dependent on treatment and the treatment itself - dialysis in particular - places substantial behavioral and psychosocial demands on the patient. Neto et al. [4] showed that the quality of life of ESRD patients is already lowered at the initiation of dialysis treatment, which was clearly evidenced in the role limitations due to physical function and emotional function aspects. Various studies demonstrated lowered quality of life of patients with ESRD in a later phase of the dialysis treatment compared to general population samples [5–9].

Results of a literature study revealed that people with chronic renal insufficiency experience difficulties in participating in various domains of life, such as paid work, sports and other social and leisure activities [10]. It seems in particular difficult to combine dialysis treatment with a paid job: several studies found labour participation rates around 24% in dialysis patients aged below 65 [11–13]. It is notable that people with CKD who are being prepared for renal replacement therapy (pre-dialysis patients; CKD stage IV) already experience work-related problems. Results from a Dutch study showed that patients mainly drop out the labor market before the start with dialysis treatment: at the start of the treatment only 35% of the patients, aged 18 to 64 years, had a paid job compared to 61% in the general population in 1997, the year the study was carried out [14]. A Swedish study among pre-dialysis patients and patients on dialysis demonstrated that around 30% of the pre-dialysis patients and more than 50% of the dialysis patients reported stressors with respect to work and leisure time [15].

Restrictions with regard to labor participation can have serious drawbacks for a person's well-being. Work is generally good for physical and mental health and well-being, and unemployment is associated with negative health effects [16]. Moreover, participation in general is important for feelings of autonomy and self-esteem. According to Self-Determination Theory (SDT) autonomy is one of the basic psychological needs for optimal functioning [17]. Reis et al. [18] found that variations in the fulfilment of autonomy independently predicted variability in daily well-being. Factors in the person or situation that facilitate autonomy are thus expected to enhance well-being, whereas factors that detract from fulfilment of this need will undermine well-being. In the SDT view, self-esteem is a derivative or by-product of need dynamics. When the fulfilment of the need for autonomy is hindered, one's experience of self-worth is also damaged, leading to either insecure or low self-esteem [19]. The feelings of self-worth depending on a person's experience, is referred to as state self-esteem. Research showed that high as well as stable self-esteem are associated with greater psychological well-being [20].

In light of these findings it is important to uncover the factors that influence feelings of autonomy, self-esteem and labor participation in patients with CKD. Socio-demographic factors (e.g. age, educational level) and medical factors (e.g. severity of the health condition, type of treatment) obviously determine the extent to which patients with CKD participate in paid jobs. Besides these factors, psychological factors may be important for labor participation and perceived autonomy as well, in particular the way patients view their illness and treatment [10]. Braun Curtin et al. [11] demonstrated that employed dialysis patients did not feel limited by their health in the hours they worked or the kind of work in which they could engage. Unemployed patients on the other hand, perceived their illness as a barrier to work. These findings are important since both patient groups did not differ with respect to objective health indicators.

The first aim of the study was to investigate the extent to which pre-dialysis patients experience feelings of autonomy and self-esteem, and participate in the work domain. Secondly, we wished to explore the content of patients' illness and treatment perceptions, and whether these perceptions are related to patients' perceived autonomy, state self-esteem and labor participation.

The mean age of the study group (64 years) and the gender distribution (64% male) corresponds with pre-dialysis patients and patients starting dialysis in the Netherlands [33, 34]. By comparing the mean scores on the autonomy measures of the total group with the answer scale, the results indicate that patients feel less autonomous because of their health condition or otherwise. In spite of this, most patients reported a high level of self-esteem. The autonomy and self-esteem levels of the pre-dialysis patients are slightly higher than the reported levels by patients on dialysis [12].

Looking at the mean illness and treatment perceptions of pre-dialysis patients it is noticed that patients are quite worried about their illness (M = 6.9) and believe that they themselves have rather little control over their illness (M = 4.7). To compare, patients on dialysis reported mean levels of 6.3 on the 'concern' dimension and 4.9 on the 'personal control' dimension [12]. In a study of Broadbent et al. people with diabetes and people with asthma reported higher mean levels of personal control (M = 6.7) [30]. Feelings of personal control are important for dialysis patients' quality of life [35, 9]. Personal control over the illness refers to the feeling that one can influence the course of the illness and one can fit the disease and treatment into daily life. In order to manage their illness pre-dialysis patients obviously are dependent on treatment. However, this does not indicate that there are no possibilities for personal control. It is of great importance that pre-dialysis patients practice self care behaviors, such as following diets and performing daily exercise in order to optimise their health condition [36]. However, patients in this stage of the illness got the news that they have to start with renal replacement therapy in the near future, which indicates that despite of their self care activities they apparently were not able to remain sufficient renal function. This knowledge might have a negative effect on patients' personal control beliefs.

On the whole, the correlation analyses demonstrated that as patients hold more positive beliefs about their illness and their current treatment, they perceive more autonomy (both global and health related) and have a higher self-esteem. In light of these findings it is important to point out the difference between the construct of personal control and the construct of autonomy, since autonomy is often incorrectly equated with ideas of internal locus of control [37, 38]. Beliefs of personal control reflect individuals' beliefs regarding the extent to which one feels that one can control or influence an outcome, for example one's illness. However, people are autonomous when they act in accord with their authentic interests or integrated values and desires [17, 37–39]. To make the distinction more explicit, a person can experience control over carrying out a walking program, but not feel intrinsically motivated, and thus do not act in accordance with his/her own values.

The regression analyses revealed that the illness and treatment perceptions explain a substantial amount of variance in predicting both global autonomy and state self-esteem after controlling for background characteristics. These results illustrate that less perceived disruption by the treatment upon life is a significant predictor of state self-esteem. The findings furthermore suggest that less perceived impact of the treatment upon life is an important determinant of global autonomy as well. Treatment in the pre-dialysis phase in most cases includes taking pharmacotherapy and following a diet. Although these treatments are far less disruptive than dialysis treatment, the findings show that treatment already is a significant theme in this stage of the illness. Illness representations are considered to be constantly updated as new experiences and knowledge are acquired [22]. In this transition phase of treatments, in which patients receive information on all available renal replacement therapies, it therefore can be expected that patients are more occupied with treatment in general, both their current treatment as well as their future treatment.

It should be noted that a large amount of variance remained unexplained. This indicates that other factors are of influence as well, for example the extent to which people in the patient's close environment, like the patient's partner or care providers, support the patient. Moreover, health related perceived autonomy could not be predicted by the illness perceptions and treatment perceptions. An explanation for this finding might be that patients are inclined to interpret 'health' as 'physical health'. At this stage of the illness, the renal disease - in most cases - will however not be associated with severe physical symptoms, which is also reflected by the mean score on the 'identity' dimension.

Because of the relatively old age of the study group (M = 64 years), only 45 patients (42%) were of working age (18-64 years). Fifty-one percent of the patients aged between 18 and 64 years performed paid work for at least 12 h per week, which is a higher percentage compared to dialysis patients; 24% [12], though considerably lower than that of the general Dutch population between the ages of 15-64 years; 65% [40]. Thus, as suggested by Van Manen et al. [14], drop out of the labor market already occurs before patients start with dialysis treatment. Furthermore, the results show that, despite of their health condition, patients of working age place relatively high importance on carrying out a paid job. These findings point to importance and necessity of work related assistance in an early stage of the illness process. We wish to mention here that the average age of the working age group (18-64 years) was rather high (50 years) and 53% of the working age group was 50 years or older. To put this into perspective, in 2006, 32% of the Dutch people aged 20-64 years were 50-64 years [40]. Notwithstanding that, our results suggest that labour participation in pre-dialysis patients is indeed lower than in the general population. Because of the small number of patients aged 18-64 years, we could not investigate the relationships between patients' perceptions of their illness and current treatment on the one hand and employment on the other hand more thoroughly. The findings, however, do show some trends: employed patients perceive their treatment as less disruptive and their illness as better controllable by self care and medical care than unemployed patients.

A limitation of this study is the replacement of the missing values on the variable comorbidity with the mean value of the total study group. Mean substitution preserves the mean of a variable's distribution; however, mean substitution typically distorts other characteristics of a variable's distribution (i.e., variance, median) [41]. In spite of this we decided to substitute the missing values by the mean in order to be able to make maximal use of the data of all our cases. Another issue to note is the use of single-item measures in order to minimize the burden on respondents. Single-item measures are sometimes seen as less psychometrically sound than multiple-items. However, several studies show that single-item measures and their multiple counterparts are comparable [42, 43]. Moreover, Gardner et al. [42] demonstrate that a well-developed single item measure can be appropriate in avoiding common methods variance, which is often a problem with psychological measures that require respondent self-reports of attitudes, beliefs, perceptions, and the like. Furthermore, it is noteworthy that the present study had a cross-sectional design which means that no conclusions can be drawn regarding the causality of the observed relationships. Notwithstanding this limitation, our results suggest that the beliefs pre-dialysis patients hold about their illness and treatment are important factors for patients' sense of (global) autonomy and self-esteem. Finally, it should be noted that the study sample was rather small (N = 109), as well as the working age sample (N = 45). Consequently there was little statistical power to demonstrate relationships between perceptions and labor participation in particular. Future research should take this issue into account. It would be worthwhile to investigate these relationships once again in a larger sample of pre-dialysis patients.

In light of the findings it seems important that patients with severe CKD are educated by a multi-professional team, comprising of nephrologists, dialysis nurses as well as employment experts and social workers, on the possibilities to combine CKD and its treatment with daily activities, including work. By means of education, positive (realistic) beliefs might be stimulated and negative beliefs may be prevented or challenged. This might contribute to a greater sense of autonomy and self-esteem as well as to participation in general. This education should take place as soon as possible. Research suggests that interventions to change cognitions should focus on patients in an early stage of the illness process [44]. The best moment to offer interventions to alter maladaptive beliefs in patients with CKD seems to be in the pre-dialysis phase (preferably even before CKD stage IV) or at the start of renal replacement therapy, in which patients are most susceptible to change. In the Netherlands, psychological support is not yet a primary area of attention in pre-dialysis care and renal care in general. It is therefore important that interventions which focus on these psychological concepts are developed [45].