- Email: [email protected]
Illness beliefs of patients on home parenteral nutrition (HPN) and their relation to emotional distress
ARTICLE IN PRESS Clinical Nutrition (2005) 24, 896–903
http://intl.elsevierhealth.com/journals/clnu
ORIGINAL ARTICLE
Illness beliefs of patients on home parenteral nutrition (HPN) and their relation to emotional distress Do ´nal G. Fortunea,b,, Jacqui Vardenb, Sophie Parkerc, Lindsay Harperb, Helen L. Richardsc, Jon L. Shafferb a
Department of Behavioural Medicine, Hope Hospital, Salford, UK Intestinal Failure Unit, Hope Hospital, Salford, UK c Academic Division of Clinical Psychology, Wythenshawe Hospital, University of Manchester, UK b
Received 8 April 2005; accepted 20 May 2005
KEYWORDS Intestinal failure; HPN; Psychology; Beliefs; Distress
Summary Background and aims: Intestinal failure (IF) is likely to be the source of significant emotional distress for patients; however, little is known about the system of beliefs held by patients on home parenteral nutrition (HPN) that may underpin such distress. The present study aimed to: (1) examine the ‘common-sense’ representation of IF in patients on HPN; (2) investigate whether there were any differences in such representations with regard to primary diagnosis, clinical history or aspects of treatment; and (3) test the relative importance of psychological, disease and treatment factors in accounting for IF-specific emotional outcome (feelings of anger, upset, anxiety, low mood, and fear). Methods: Sixty-one patients with IF on HPN completed an assessment of their beliefs about causes of their condition, consequences, symptoms experienced, personal and treatment control, chronicity and recurrence, and emotional representations (feelings of anger, upset, anxiety, low mood, and fear). Standard clinical information was also gathered from patients. Results: Neither primary diagnosis, age, duration since start of HPN, number of nights on HPN, gender, presence of a stoma, or age at onset of HPN showed any significant differential effect on emotional representations. The principal predictors of emotional representations were: (1) poorer appraisals of patients’ ability to exert personal control over aspects of their condition and treatment; and (2) the perception that the condition and treatment makes little sense to the patient (illness coherence).
Corresponding author. Department of Behavioural Medicine, Clinical Sciences Building, Hope Hospital Stott Lane, Salford M6 8HD,
UK. Tel.: +44 161 206 5588; fax: +44 161 206 5589. E-mail address: [email protected] (D.G. Fortune). 0261-5614/$ - see front matter & 2005 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved. doi:10.1016/j.clnu.2005.05.015
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Conclusions: The current study demonstrates that the illness and their treatments per se are insufficient to account for patients’ emotional distress. Rather, cognitive variables, chiefly beliefs about personal control and illness coherence account for more of the variance in emotional outcome than any other clinical or health-related variable assessed in the current study. & 2005 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
Introduction There is a paucity of relevant research on the extent of psychological difficulties encountered by patients with intestinal failure (IF) despite the significant challenges the condition can bring for patients and their families.1,2 Patients commonly report feeling a burden to others, feeling isolated, experiencing a loss of sexual drive and lowered energy levels as significant factors that contribute to impairment in their quality of life.1 Moreover the additional complications of home parenteral nutrition (HPN) can result in greater numbers of HPN-treated patients being socially isolated, feeling a nuisance or burden to others, and having less self-confidence relative to patients treated by means other than HPN.3 Whilst this data provides a helpful description of the burden of HPN in IF patients, it does not provide much information in terms of risk and protective factors for the emergence of distress, or the nature of patients beliefs about their condition. Burgeoning psychological research has demonstrated that patients with various conditions actively construct a complex cognitive representation of their condition and treatment.4–6 Cognitive representations about a condition are based on generic memorized information about health and illness, information patients will receive in the medical domain, and lay information from family and friends and from the wider media. The major attributes of illness representation are essentially oriented around eight dimensions of patients’ experience: (i) beliefs about meaning of symptoms, (ii) beliefs about the chronicity or recurrence of the condition, (iii) beliefs about the severity of consequences, (iv) ideas about personal control of patients illness and treatment, (v) confidence in current treatments, (vi) the extent to which the condition makes sense to the patient, (vii) perceived causes of the condition, and (viii) patients emotional response to their condition. Previous studies have demonstrated that illness perceptions have been found to predict psychological well-being in chronic fatigue syndrome, rheumatoid arthritis and irritable bowel syndrome,7–9 self-management of diabetes and osteoarthritis,10,11 and return to work after myocardial infarction.12 This study is the
first to conduct a multidimensional investigation of illness representations in IF patients on HPN. The purpose of the present study was therefore to examine the ‘common-sense’ representation of IF in patients on HPN. Secondly, to examine whether there were any differences in such representations with regard to primary diagnosis, clinical history or aspects of treatment. Thirdly we set out to test the relative importance of psychological, disease and treatment factors in accounting for IF-specific emotional outcome.
Patients and methods Patients with IF attending the Home Parenteral Nutrition Out-patient clinic at Hope Hospital, Manchester, UK, were invited to participate in the study. Patients were eligible to participate if they were aged between 18 and 75 years and had a current diagnosis of IF. Patients were not eligible to participate if they were diagnosed with any axis II psychiatric disorder (DSM-IV).13 A total of four patients failed to meet inclusion criteria. The study was approved by Salford and Trafford Local Research Ethics Committee.
Assessment procedures Participants completed the Revised Illness Perception Questionnaire (IPQ-R)14 as an assessment of patients beliefs about their condition. This interview schedule provides an assessment of patients’ beliefs about their condition. The measure has been widely used in medical and surgical populations.7–12,14,15 Beliefs about intestinal failure The IPQ-R14 consists of nine sub-scales which, in this study, included: (i) Illness identity—beliefs about the frequency and meaning of symptoms, (ii) Time-line—beliefs about the chronicity of the condition, (iii) Time-line cyclical—beliefs about recurrence of the condition,
ARTICLE IN PRESS 898 (iv) Consequences—beliefs about the severity of the condition’s consequences, (v) Personal control—ideas about the degree of personal control patients hold over their condition and treatment, (vi) Treatment control—confidence in current treatments, (vii) Illness coherence—the extent to which the condition makes sense to the patient, (viii) Causal attributions—perceived causes of the condition, and (ix) Emotional representations—patients emotional response to their condition (comprising feelings of anger, upset, anxiety, low mood, and fear). An adjusted mean score (sum of the scale items divided by the number of items) was calculated, with a possible maximum of five for each sub-scale to permit comparison with other published studies using this assessment.
Clinical history Data collected included primary diagnosis, presence or absence of a stoma, age at onset of HPN, duration since onset of HPN, and number of nights per week on HPN.
Statistical analysis As the data was normally distributed, parametric statistics were employed. Pearson’s correlation was used to investigate relations between variables. Differences in means were analysed by t-test and analysis of variance models (ANOVA) as appropriate. The principal research question as to whether medical or cognitive psychological factors accounted for more of the variance in emotional representations (outcome) was undertaken by stepwise multiple regression.
D.G. Fortune et al. SD 13.5), and length of time on HPN ranged from 1 year to 15 years (mean 5.6 years, SD 4.6). Ten percent of patients were on HPN for two nights or less, 32% for four nights or less, 64% for six nights or less and a further 36% for seven nights. The mean number of nights patients spent on HPN per week was five. Patients who were invited to participate and declined (42% n ¼ 44) were broadly similar to participants in terms of age (t ¼ 1:49, P ¼ 0:14), age at onset of HPN (t ¼ 1:31, P ¼ 0:19), presence of a stoma (t ¼ 1:94, P ¼ 0:10), or duration on HPN (t ¼ 1:21, P ¼ 0:21). The primary diagnosis was divided into three categories; inflammatory bowel disease (n ¼ 27; 44%), vascular occlusion (n ¼ 16; 26%), and other (n ¼ 18; 30%) comprising volvulus, cancer sequelae (e.g., Duke’s C, radiation enteritis) and adverse surgical events (e.g., perforation of uterus, avulsion of small bowel from mesentery). Seventy-five percent of patients had a stoma. The most commonly reported symptoms currently experienced by patients as part of the condition were loss of strength, recurrent weight loss, nausea and pain (Fig. 1). The most commonly cited beliefs held by patients about particular causes of their condition were in relation to chance or bad luck, poor medical care in the past, and stress (Fig. 2). Causal beliefs were grouped according to conceptual and empirical models into psychological beliefs, beliefs about risk, beliefs about cause being due to a chance occurrence, and immunity.
Breathlessness Forgetfulness Itching Lost Strength Dizziness Sleep Difficulties Upset Stomach Headaches Wheeziness Sore Eyes
Results
Stiff Joints Fatigue
A total of 105 patients were invited to participate in the study. Eventual participants included 61 patients (36 female and 25 male). This number represents 54% of patients under the care of the Intestinal Failure Unit at Hope Hospital, Salford, UK. Participants were aged between 18 and 70 years (mean 51; SD 13). Patients’ age at onset of their condition ranged from 14.3 to 66 years (mean 44;
Weight loss Nausea Sore throat Pain 0
20
40
60
80
100
Figure 1 Symptoms patients associate with their condition.
ARTICLE IN PRESS Illness beliefs and emotional distress in HPN patients
Comparison of profile of HPN patients with previously published studies using the IPQ-R Table 1 displays IPQ-R assessment scores of present HPN sample for comparison with published IPQ-R scores from patients with systemic sclerosis (SSc),15 chronic pain,14 and psoriasis.16 Scores in the table suggest that of the four patient groups, HPN patients had the highest emotional representation scores (poorest emotional outcome), held the strongest belief that their condition would have a chronic course (timeline), and scored the lowest on beliefs in personal control and treatment control of their condition. Furthermore, HPN patients reported greater number Immunity Personality Accident/Injury Smoking Alcohol Ageing Emotional State
899 of symptoms, and yet had the strongest beliefs that the condition and its treatment made sense to them (illness coherence). They scored lower than patients with SSc or chronic pain syndrome (psoriasis patients were not assessed by this subscale) on beliefs that psychological factors were responsible for the onset of their condition, or that risk factors such as diet, or hereditary were responsible.
Gender differences There were no significant differences between men and women participants on age (t ¼ 0:17, P ¼ 0:82), duration on HPN (t ¼ 0:02, P ¼ 0:98), age at onset (t ¼ 0:82, P ¼ 0:41), primary diagnosis (w2 ¼ 1:74, P ¼ 0:41), or presence of a stoma (w2 ¼ 0:93, P ¼ 0:50). Women were less likely to report confidence in the ability of treatment to control their condition (t ¼ 2:28, P ¼ 0:02). There were no other significant differences between men and women on the strength of beliefs held (t’so1:55, P40:12).
Overwork Family Problems Mental Attitude
Stoma
Own Behaviour Pollution Poor Medical care Chance/Luck Diet/Eating Habits Germ/Virus Hereditary Stress 0
10
20
30
40
50
Figure 2 Beliefs about causes of intestinal failure.
60
Presence of a stoma did not significantly affect patients’ beliefs about frequency of symptoms, beliefs about causes, chronicity or recurrence, severity of consequences, personal control, treatment control, or emotional representations (t’so 1:47, P40:14). Whilst there was a trend for patients with a stoma to report lower illness coherence this did not reach statistical significance (t ¼ 1:76, P ¼ 0:08).
Table 1 Descriptive statistics (mean scores and standard deviations) for illness perception questionnaire (IPQ-R) dimensions in HPN patients and patients with systemic sclerosis,15 chronic pain,14 and psoriasis.20 Illness perceptions Emotional representations Time-line Time-line cyclical Consequences Personal control Treatment control Illness coherence Illness identity (symptoms) Causal attributions Psychological causation Immunity Risk Chance or bad luck
HPN
SSc
3.25 4.40 3.00 3.50 2.96 2.85 3.72 7.19
(0.84) (0.58) (0.99) (0.50) (0.77) (0.69) (0.86) (3.40)
11.55 6.70 14.81 5.18
(4.19) (2.50) (3.45) (1.74)
Chronic pain
3.05 (0.99) 4.22 (0.63) 3.46 (0.99) 3.76 (0.76) 2.89 (0.72) 2.97 (0.64) 3.14 (0.97) 7.0 (3.30) 15.02 8.54 15.23 5.41
(4.28) (2.42) (4.31) (1.39)
Psoriasis
3.21 3.85 3.21 3.90 3.07 2.88 2.67 6.19
(0.69) (0.73) (0.97) (0.64) (0.66) (0.67) (0.95) (2.40)
3.19 4.13 3.43 3.34 3.20 3.55 3.26 5.43
12.48 5.98 15.32 6.54
(5.21) (2.45) (4.79) (1.82)
— — — —
(0.84) (0.60) (0.75) (0.82) (0.83) (0.56) (1.15) (2.72)
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Primary diagnosis ANOVA demonstrated an effect of primary diagnosis (IBD, vascular occlusion, or mixed category) on perceptions about the recurrent nature of the condition, such that patients with vascular occlusion held significantly stronger beliefs that they would experience similar events in the future when compared both with patients with IBD and the mixed category (time-line cyclical—F 2;58 ; ¼ 7:84, P ¼ 0:001). In addition patients with IBD when compared with patients with other primary diagnoses reported a significantly greater frequency of general, non-specific symptoms rather than symptoms specific to their condition (F 2;58 ¼ 4:38, P ¼ 0:01). There was no further effects of primary diagnosis on beliefs (F’so2:09, P ¼ 0:13), on duration with HPN (F 2;58 ¼ 0:58, P ¼ 0:56), or age at onset of HPN (F 2;58 ¼ 0:12, P ¼ 0:98). A new variable, duration on HPN was created by dividing the participants into two groups around a median split in the data (4 years 8 months). Emotional representations did not differ as a function of duration on HPN (t ¼ 0:63, P ¼ 0:53). Understandably, patients who were on HPN for less than 5 years, were significantly less likely to believe that their condition would be chronic or enduring (t ¼ 2:76, P ¼ 0:01), and were significantly more likely to hold stronger beliefs in the ability of treatment to effect control of the condition (t ¼ 2:13, P ¼ 0:01) than patients who were on HPN for longer. Furthermore, patients who were on HPN for longer than 4 years 8 months reported a stronger belief that the condition had greater coherence for the patient (t ¼ 3:50, P ¼ 0:001).
Univariate associations Table 2 shows the correlation matrix. Emotional representations were associated with stronger beliefs in the severity of consequences of patients’ condition, a stronger illness identity (more symptoms experienced), stronger beliefs in personal control, and greater confidence in treatment control. No other variable was significantly associated with emotional representations.
Predictors of emotional representations In order to provide a more stringent test of the associations and to provide statistical control for the shared variance between variables measured, stepwise multiple regression was performed on the data. Emotional representations was the
D.G. Fortune et al. dependent variable, and variables which showed zero order correlations of greater than Po0:05 (see Table 2), were entered into the regression analysis. Thus the cognitive variables of beliefs about the severity of consequences, confidence in treatment control, illness coherence, and beliefs about personal control were the predictor variables in the analysis. (Table 3) Results suggest that stronger emotional representations are best predicted by patients reporting less illness coherence and by having weaker beliefs in personal control over their condition. These two variables account for 26% of the variance in emotional representations. Beliefs about the severity of the consequences of HPN, or confidence in treatment control did not account for any significant variance in emotional representations in the regression analysis. Further clinical variables (primary diagnosis, presence of a stoma, or duration on HPN) were not directly associated with emotional representations.
Discussion This study has demonstrated that emotional representations (feelings of anger, upset, anxiety, low mood, and fear) held by patients with IF on HPN were best predicted by the extent to which the condition and treatment makes sense to the patient, and their beliefs that they have some personal agency or control over aspects of their condition. The results of this study form part of a growing body of research demonstrating that the clinical severity of a condition or the vagaries of a treatment tend to be the poorest predictors of patients’ emotional outcome. Similar results demonstrating the primacy of patients’ thoughts and beliefs over disease-oriented factors has been reported in conditions ranging from skin disease,4 rheumatic diseases,15 cancer,17 cardiac disease,12 and neurological conditions.18 This consensus in results across different conditions is due to the fact that patients are not passive objects upon which disease impacts. Rather they are active processors of information about external states and internal events, who construct a comprehensive and complex model of their condition in an attempt to make sense of their condition and its treatment. Any potential effects of disease, illness or treatment on patients are therefore mediated by patients psychological model. This assertion is commensurate with the clinical observation that some patients can be distressed by objectively minor illness vagaries, whilst other patients seem to cope better with comparatively more severe costs.
0.19 0.11 0.07 0.36** 0.38** 0.26* 0.32* 0.01 0.06 0.08 0.09 0.07 0.14 0.04 0.14
1
0.12 0.28* 0.48** 0.08 0.02 0.19 0.03 0.09 0.03 0.06 0.01 0.01 0.02 0.19
2
Correlation matrix for study variables.
Emotional representations Illness identity (symptoms) Time-line Time-line cyclical Consequences Personal control Treatment control Illness coherence Psychological causes Immunity causes Chance or bad luck causes Risk causes Age Duration on HPN Age at Onset of HPN Number of nights feeding
*Po0:05. **Po0:01.
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.
Table 2
0.13 0.12 0.36** 0.48** 0.17 0.08 0.02 0.18 0.03 0.05 0.36** 0.09 0.14
3
0.29* 0.01 0.02 0.15 0.11 0.14 0.15 0.01 0.47** 0.09 0.36* 0.09
4
0.22 0.23 0.09 0.11 0.07 0.14 0.15 0.18 0.04 0.06 0.14
5
7
8
9
10
11
12
13
14
15
0.59** 0.05 0.05 0.05 0.10 0.05 0.07 0.05 0.06 0.18 0.18 0.12 0.03 0.14 .06 0.03 0.10 0.19 0.58** 0.35** 0.25 0.06 0.10 0.07 0.07 0.11 0.09 0.14 0.11 0.24 0.29* 0.04 0.20 0.12 0.17 0.01 0.05 0.04 0.10 0.22 0.12 0.05 0.14 0.92** 0.40** 0.19 0.13 0.07 0.09 0.18 0.24 0.01 0.08 0.02 0.12
6
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Table 3 Regression analysis testing the significance of change in explained variance on emotional representations. Variable
R
Adj R2
R2 change
F change
df
P
B
Personal control Illness coherence
0.41 0.53
0.16 0.26
0.17 0.11
11.99 9.10
1, 58
0.001 0.004
0.43 0.34
A further interesting finding concerns the result that patients who were on HPN for longer than 5 years reported a stronger belief that the condition made increased sense for the patient, despite the attendant difficulties that being on HPN for longer can bring. It is therefore likely that the broad clinical observation that patients who are on HPN for longer tend to do better emotionally than patients with a shorter treatment duration3,19 results from the association between duration and an increased sense of illness coherence. Results also demonstrated that patients with vascular occlusion held significantly stronger beliefs that they would experience similar events in the future when compared with patients with IBD and the mixed category. While their emotional representation scores were higher than the other two groups, this did not reach statistical significance. Nonetheless, these patients with vascular occlusion are likely to demonstrate increased anticipatory anxiety as beliefs about future-oriented threat tend to be crucially involved in the development and maintenance of clinically relevant anxiety states. HPN patients when compared with previously published data from SSc, chronic pain and psoriasis were doing poorer emotionally, reported more symptoms, had less personal control but higher illness coherence. Given the importance of both personal control and illness coherence in emotional outcome found in the current study, ways of preserving illness coherence and increasing personal control for HPN patients deserves investigation. It is important to recognize that emotional representations are not necessarily synonymous with diagnostic categories of dysthymia, major depression or anxiety disorders. Indeed recent research has suggested that over one third of HPN patients have levels of anxiety and over one quarter levels of depression, of sufficient severity to be classified as clinically significant cases.20 Whilst the majority of patients will not meet diagnostic criteria, a significant additional number will be experiencing adverse emotional representations as they strive to adjust to their condition and
its treatment. Such levels of distress, whilst perhaps not fully warranting a diagnostic category are nonetheless difficult to negotiate and challenge for patients and their families and are likely to significantly interfere with treatment and wellbeing. While the number of patients participating in the study was higher than previous studies3,19 the overall response rate of patients from the possible participant pool agreeing to participate was somewhat lower. Unlike other studies we did not send out reminders to patients, which is likely to have influenced the numbers of patients participating. However, patients were broadly similar in terms of age, age at onset, presence of a stoma and duration on HPN so we can be quite confident about generalizing these finding to the larger pool of HPN patients under our care. There is a need for further investigation of mediating factors not simply as it pertains to patients but also in relation to key family members. There is indeed burgeoning evidence that carers representations in other chronic and stigmatizing conditions can either help or hinder patients. Moreover, divergence in beliefs about chronic and stigmatizing conditions between patients and their spouses tends to be associated with depression in patients and worry in their spouses.16 Further research is also required to evaluate the effects of specifically targeting psychological interventions to patients implicit model of their condition, which has begun to be evaluated in other chronic conditions.21 In conclusion, the current study has demonstrated a central role for illness coherence and personal control in moderating the emotional representations of patients on HPN. Knowledge of the importance of these factors requires an approach to provision of information that is appropriate to the needs of the individual patient and is constantly assessed and delivered in a manner that promotes both coherence and personal control.22 The relationship between psychological factors, disease and illness therefore become critical for optimizing standard treatment and for accurately evaluating treatment outcomes.
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Acknowledgments Our thanks to the patients who agreed to participate in this study.
11.
12.
References 1. Carlsson E, Bosaeus I, Nordgren S. Quality of life and concerns in patients with short bowel syndrome. Clin Nutr 2003;22:445–52. 2. Smith C. Quality of life in long-term total parenteral nutrition patients and their family caregivers. J Parenter Enteral Nutr 1993;17:501–6. 3. Jeppesen PB, Langholz E, Mortensen PB. Quality of life in patients receiving home parenteral nutrition. Gut 1999;44:844–52. 4. Fortune DG, Richards HL, Griffiths CEM, Main CJ. Psychological stress, distress and disability in patients with psoriasis: Consensus and variation in the contribution of illness perceptions, coping and alexithymia. Br J Clin Psychol 2002;41:157–74. 5. Leventhal H, Diefenbach M, Leventhal E. Illness cognition: Using common-sense to understand treatment adherence and affect-cognition interactions. Cognitive Ther Res 1992; 16:143–63. 6. Brownlee S, Leventhal H, Leventhal EA. Regulation, selfregulation, and construction of the self in the maintenance of physical health. In: Boekaerts M, Pintrich PR, Zeidner M, editors. Handbook of self-regulation. San Diego, CA: Academic Press; 2000. p. 369–416. 7. Heijmans M, De Ridder D. Assessing illness representations of chronic illness: explorations of their disease-specific nature. J Behav Med 1998;21:485–503. 8. Murphy H, Dickens C, Creed F, Bernstein R. Depression, illness perception and coping in rheumatoid arthritis. J Psychosom Res 1999;46:155–64. 9. Rutter CL, Rutter DR. Illness representations, coping and outcome in irritable bowel syndrome (IBS). Br J Health Psychol 2002;7:377–91. 10. Hampson SE, Glasgow RE, Foster LS. Personal models of diabetes among older adults: relationship to self-manage-
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http://intl.elsevierhealth.com/journals/clnu
ORIGINAL ARTICLE
Illness beliefs of patients on home parenteral nutrition (HPN) and their relation to emotional distress Do ´nal G. Fortunea,b,, Jacqui Vardenb, Sophie Parkerc, Lindsay Harperb, Helen L. Richardsc, Jon L. Shafferb a
Department of Behavioural Medicine, Hope Hospital, Salford, UK Intestinal Failure Unit, Hope Hospital, Salford, UK c Academic Division of Clinical Psychology, Wythenshawe Hospital, University of Manchester, UK b
Received 8 April 2005; accepted 20 May 2005
KEYWORDS Intestinal failure; HPN; Psychology; Beliefs; Distress
Summary Background and aims: Intestinal failure (IF) is likely to be the source of significant emotional distress for patients; however, little is known about the system of beliefs held by patients on home parenteral nutrition (HPN) that may underpin such distress. The present study aimed to: (1) examine the ‘common-sense’ representation of IF in patients on HPN; (2) investigate whether there were any differences in such representations with regard to primary diagnosis, clinical history or aspects of treatment; and (3) test the relative importance of psychological, disease and treatment factors in accounting for IF-specific emotional outcome (feelings of anger, upset, anxiety, low mood, and fear). Methods: Sixty-one patients with IF on HPN completed an assessment of their beliefs about causes of their condition, consequences, symptoms experienced, personal and treatment control, chronicity and recurrence, and emotional representations (feelings of anger, upset, anxiety, low mood, and fear). Standard clinical information was also gathered from patients. Results: Neither primary diagnosis, age, duration since start of HPN, number of nights on HPN, gender, presence of a stoma, or age at onset of HPN showed any significant differential effect on emotional representations. The principal predictors of emotional representations were: (1) poorer appraisals of patients’ ability to exert personal control over aspects of their condition and treatment; and (2) the perception that the condition and treatment makes little sense to the patient (illness coherence).
Corresponding author. Department of Behavioural Medicine, Clinical Sciences Building, Hope Hospital Stott Lane, Salford M6 8HD,
UK. Tel.: +44 161 206 5588; fax: +44 161 206 5589. E-mail address: [email protected] (D.G. Fortune). 0261-5614/$ - see front matter & 2005 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved. doi:10.1016/j.clnu.2005.05.015
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Conclusions: The current study demonstrates that the illness and their treatments per se are insufficient to account for patients’ emotional distress. Rather, cognitive variables, chiefly beliefs about personal control and illness coherence account for more of the variance in emotional outcome than any other clinical or health-related variable assessed in the current study. & 2005 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
Introduction There is a paucity of relevant research on the extent of psychological difficulties encountered by patients with intestinal failure (IF) despite the significant challenges the condition can bring for patients and their families.1,2 Patients commonly report feeling a burden to others, feeling isolated, experiencing a loss of sexual drive and lowered energy levels as significant factors that contribute to impairment in their quality of life.1 Moreover the additional complications of home parenteral nutrition (HPN) can result in greater numbers of HPN-treated patients being socially isolated, feeling a nuisance or burden to others, and having less self-confidence relative to patients treated by means other than HPN.3 Whilst this data provides a helpful description of the burden of HPN in IF patients, it does not provide much information in terms of risk and protective factors for the emergence of distress, or the nature of patients beliefs about their condition. Burgeoning psychological research has demonstrated that patients with various conditions actively construct a complex cognitive representation of their condition and treatment.4–6 Cognitive representations about a condition are based on generic memorized information about health and illness, information patients will receive in the medical domain, and lay information from family and friends and from the wider media. The major attributes of illness representation are essentially oriented around eight dimensions of patients’ experience: (i) beliefs about meaning of symptoms, (ii) beliefs about the chronicity or recurrence of the condition, (iii) beliefs about the severity of consequences, (iv) ideas about personal control of patients illness and treatment, (v) confidence in current treatments, (vi) the extent to which the condition makes sense to the patient, (vii) perceived causes of the condition, and (viii) patients emotional response to their condition. Previous studies have demonstrated that illness perceptions have been found to predict psychological well-being in chronic fatigue syndrome, rheumatoid arthritis and irritable bowel syndrome,7–9 self-management of diabetes and osteoarthritis,10,11 and return to work after myocardial infarction.12 This study is the
first to conduct a multidimensional investigation of illness representations in IF patients on HPN. The purpose of the present study was therefore to examine the ‘common-sense’ representation of IF in patients on HPN. Secondly, to examine whether there were any differences in such representations with regard to primary diagnosis, clinical history or aspects of treatment. Thirdly we set out to test the relative importance of psychological, disease and treatment factors in accounting for IF-specific emotional outcome.
Patients and methods Patients with IF attending the Home Parenteral Nutrition Out-patient clinic at Hope Hospital, Manchester, UK, were invited to participate in the study. Patients were eligible to participate if they were aged between 18 and 75 years and had a current diagnosis of IF. Patients were not eligible to participate if they were diagnosed with any axis II psychiatric disorder (DSM-IV).13 A total of four patients failed to meet inclusion criteria. The study was approved by Salford and Trafford Local Research Ethics Committee.
Assessment procedures Participants completed the Revised Illness Perception Questionnaire (IPQ-R)14 as an assessment of patients beliefs about their condition. This interview schedule provides an assessment of patients’ beliefs about their condition. The measure has been widely used in medical and surgical populations.7–12,14,15 Beliefs about intestinal failure The IPQ-R14 consists of nine sub-scales which, in this study, included: (i) Illness identity—beliefs about the frequency and meaning of symptoms, (ii) Time-line—beliefs about the chronicity of the condition, (iii) Time-line cyclical—beliefs about recurrence of the condition,
ARTICLE IN PRESS 898 (iv) Consequences—beliefs about the severity of the condition’s consequences, (v) Personal control—ideas about the degree of personal control patients hold over their condition and treatment, (vi) Treatment control—confidence in current treatments, (vii) Illness coherence—the extent to which the condition makes sense to the patient, (viii) Causal attributions—perceived causes of the condition, and (ix) Emotional representations—patients emotional response to their condition (comprising feelings of anger, upset, anxiety, low mood, and fear). An adjusted mean score (sum of the scale items divided by the number of items) was calculated, with a possible maximum of five for each sub-scale to permit comparison with other published studies using this assessment.
Clinical history Data collected included primary diagnosis, presence or absence of a stoma, age at onset of HPN, duration since onset of HPN, and number of nights per week on HPN.
Statistical analysis As the data was normally distributed, parametric statistics were employed. Pearson’s correlation was used to investigate relations between variables. Differences in means were analysed by t-test and analysis of variance models (ANOVA) as appropriate. The principal research question as to whether medical or cognitive psychological factors accounted for more of the variance in emotional representations (outcome) was undertaken by stepwise multiple regression.
D.G. Fortune et al. SD 13.5), and length of time on HPN ranged from 1 year to 15 years (mean 5.6 years, SD 4.6). Ten percent of patients were on HPN for two nights or less, 32% for four nights or less, 64% for six nights or less and a further 36% for seven nights. The mean number of nights patients spent on HPN per week was five. Patients who were invited to participate and declined (42% n ¼ 44) were broadly similar to participants in terms of age (t ¼ 1:49, P ¼ 0:14), age at onset of HPN (t ¼ 1:31, P ¼ 0:19), presence of a stoma (t ¼ 1:94, P ¼ 0:10), or duration on HPN (t ¼ 1:21, P ¼ 0:21). The primary diagnosis was divided into three categories; inflammatory bowel disease (n ¼ 27; 44%), vascular occlusion (n ¼ 16; 26%), and other (n ¼ 18; 30%) comprising volvulus, cancer sequelae (e.g., Duke’s C, radiation enteritis) and adverse surgical events (e.g., perforation of uterus, avulsion of small bowel from mesentery). Seventy-five percent of patients had a stoma. The most commonly reported symptoms currently experienced by patients as part of the condition were loss of strength, recurrent weight loss, nausea and pain (Fig. 1). The most commonly cited beliefs held by patients about particular causes of their condition were in relation to chance or bad luck, poor medical care in the past, and stress (Fig. 2). Causal beliefs were grouped according to conceptual and empirical models into psychological beliefs, beliefs about risk, beliefs about cause being due to a chance occurrence, and immunity.
Breathlessness Forgetfulness Itching Lost Strength Dizziness Sleep Difficulties Upset Stomach Headaches Wheeziness Sore Eyes
Results
Stiff Joints Fatigue
A total of 105 patients were invited to participate in the study. Eventual participants included 61 patients (36 female and 25 male). This number represents 54% of patients under the care of the Intestinal Failure Unit at Hope Hospital, Salford, UK. Participants were aged between 18 and 70 years (mean 51; SD 13). Patients’ age at onset of their condition ranged from 14.3 to 66 years (mean 44;
Weight loss Nausea Sore throat Pain 0
20
40
60
80
100
Figure 1 Symptoms patients associate with their condition.
ARTICLE IN PRESS Illness beliefs and emotional distress in HPN patients
Comparison of profile of HPN patients with previously published studies using the IPQ-R Table 1 displays IPQ-R assessment scores of present HPN sample for comparison with published IPQ-R scores from patients with systemic sclerosis (SSc),15 chronic pain,14 and psoriasis.16 Scores in the table suggest that of the four patient groups, HPN patients had the highest emotional representation scores (poorest emotional outcome), held the strongest belief that their condition would have a chronic course (timeline), and scored the lowest on beliefs in personal control and treatment control of their condition. Furthermore, HPN patients reported greater number Immunity Personality Accident/Injury Smoking Alcohol Ageing Emotional State
899 of symptoms, and yet had the strongest beliefs that the condition and its treatment made sense to them (illness coherence). They scored lower than patients with SSc or chronic pain syndrome (psoriasis patients were not assessed by this subscale) on beliefs that psychological factors were responsible for the onset of their condition, or that risk factors such as diet, or hereditary were responsible.
Gender differences There were no significant differences between men and women participants on age (t ¼ 0:17, P ¼ 0:82), duration on HPN (t ¼ 0:02, P ¼ 0:98), age at onset (t ¼ 0:82, P ¼ 0:41), primary diagnosis (w2 ¼ 1:74, P ¼ 0:41), or presence of a stoma (w2 ¼ 0:93, P ¼ 0:50). Women were less likely to report confidence in the ability of treatment to control their condition (t ¼ 2:28, P ¼ 0:02). There were no other significant differences between men and women on the strength of beliefs held (t’so1:55, P40:12).
Overwork Family Problems Mental Attitude
Stoma
Own Behaviour Pollution Poor Medical care Chance/Luck Diet/Eating Habits Germ/Virus Hereditary Stress 0
10
20
30
40
50
Figure 2 Beliefs about causes of intestinal failure.
60
Presence of a stoma did not significantly affect patients’ beliefs about frequency of symptoms, beliefs about causes, chronicity or recurrence, severity of consequences, personal control, treatment control, or emotional representations (t’so 1:47, P40:14). Whilst there was a trend for patients with a stoma to report lower illness coherence this did not reach statistical significance (t ¼ 1:76, P ¼ 0:08).
Table 1 Descriptive statistics (mean scores and standard deviations) for illness perception questionnaire (IPQ-R) dimensions in HPN patients and patients with systemic sclerosis,15 chronic pain,14 and psoriasis.20 Illness perceptions Emotional representations Time-line Time-line cyclical Consequences Personal control Treatment control Illness coherence Illness identity (symptoms) Causal attributions Psychological causation Immunity Risk Chance or bad luck
HPN
SSc
3.25 4.40 3.00 3.50 2.96 2.85 3.72 7.19
(0.84) (0.58) (0.99) (0.50) (0.77) (0.69) (0.86) (3.40)
11.55 6.70 14.81 5.18
(4.19) (2.50) (3.45) (1.74)
Chronic pain
3.05 (0.99) 4.22 (0.63) 3.46 (0.99) 3.76 (0.76) 2.89 (0.72) 2.97 (0.64) 3.14 (0.97) 7.0 (3.30) 15.02 8.54 15.23 5.41
(4.28) (2.42) (4.31) (1.39)
Psoriasis
3.21 3.85 3.21 3.90 3.07 2.88 2.67 6.19
(0.69) (0.73) (0.97) (0.64) (0.66) (0.67) (0.95) (2.40)
3.19 4.13 3.43 3.34 3.20 3.55 3.26 5.43
12.48 5.98 15.32 6.54
(5.21) (2.45) (4.79) (1.82)
— — — —
(0.84) (0.60) (0.75) (0.82) (0.83) (0.56) (1.15) (2.72)
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Primary diagnosis ANOVA demonstrated an effect of primary diagnosis (IBD, vascular occlusion, or mixed category) on perceptions about the recurrent nature of the condition, such that patients with vascular occlusion held significantly stronger beliefs that they would experience similar events in the future when compared both with patients with IBD and the mixed category (time-line cyclical—F 2;58 ; ¼ 7:84, P ¼ 0:001). In addition patients with IBD when compared with patients with other primary diagnoses reported a significantly greater frequency of general, non-specific symptoms rather than symptoms specific to their condition (F 2;58 ¼ 4:38, P ¼ 0:01). There was no further effects of primary diagnosis on beliefs (F’so2:09, P ¼ 0:13), on duration with HPN (F 2;58 ¼ 0:58, P ¼ 0:56), or age at onset of HPN (F 2;58 ¼ 0:12, P ¼ 0:98). A new variable, duration on HPN was created by dividing the participants into two groups around a median split in the data (4 years 8 months). Emotional representations did not differ as a function of duration on HPN (t ¼ 0:63, P ¼ 0:53). Understandably, patients who were on HPN for less than 5 years, were significantly less likely to believe that their condition would be chronic or enduring (t ¼ 2:76, P ¼ 0:01), and were significantly more likely to hold stronger beliefs in the ability of treatment to effect control of the condition (t ¼ 2:13, P ¼ 0:01) than patients who were on HPN for longer. Furthermore, patients who were on HPN for longer than 4 years 8 months reported a stronger belief that the condition had greater coherence for the patient (t ¼ 3:50, P ¼ 0:001).
Univariate associations Table 2 shows the correlation matrix. Emotional representations were associated with stronger beliefs in the severity of consequences of patients’ condition, a stronger illness identity (more symptoms experienced), stronger beliefs in personal control, and greater confidence in treatment control. No other variable was significantly associated with emotional representations.
Predictors of emotional representations In order to provide a more stringent test of the associations and to provide statistical control for the shared variance between variables measured, stepwise multiple regression was performed on the data. Emotional representations was the
D.G. Fortune et al. dependent variable, and variables which showed zero order correlations of greater than Po0:05 (see Table 2), were entered into the regression analysis. Thus the cognitive variables of beliefs about the severity of consequences, confidence in treatment control, illness coherence, and beliefs about personal control were the predictor variables in the analysis. (Table 3) Results suggest that stronger emotional representations are best predicted by patients reporting less illness coherence and by having weaker beliefs in personal control over their condition. These two variables account for 26% of the variance in emotional representations. Beliefs about the severity of the consequences of HPN, or confidence in treatment control did not account for any significant variance in emotional representations in the regression analysis. Further clinical variables (primary diagnosis, presence of a stoma, or duration on HPN) were not directly associated with emotional representations.
Discussion This study has demonstrated that emotional representations (feelings of anger, upset, anxiety, low mood, and fear) held by patients with IF on HPN were best predicted by the extent to which the condition and treatment makes sense to the patient, and their beliefs that they have some personal agency or control over aspects of their condition. The results of this study form part of a growing body of research demonstrating that the clinical severity of a condition or the vagaries of a treatment tend to be the poorest predictors of patients’ emotional outcome. Similar results demonstrating the primacy of patients’ thoughts and beliefs over disease-oriented factors has been reported in conditions ranging from skin disease,4 rheumatic diseases,15 cancer,17 cardiac disease,12 and neurological conditions.18 This consensus in results across different conditions is due to the fact that patients are not passive objects upon which disease impacts. Rather they are active processors of information about external states and internal events, who construct a comprehensive and complex model of their condition in an attempt to make sense of their condition and its treatment. Any potential effects of disease, illness or treatment on patients are therefore mediated by patients psychological model. This assertion is commensurate with the clinical observation that some patients can be distressed by objectively minor illness vagaries, whilst other patients seem to cope better with comparatively more severe costs.
0.19 0.11 0.07 0.36** 0.38** 0.26* 0.32* 0.01 0.06 0.08 0.09 0.07 0.14 0.04 0.14
1
0.12 0.28* 0.48** 0.08 0.02 0.19 0.03 0.09 0.03 0.06 0.01 0.01 0.02 0.19
2
Correlation matrix for study variables.
Emotional representations Illness identity (symptoms) Time-line Time-line cyclical Consequences Personal control Treatment control Illness coherence Psychological causes Immunity causes Chance or bad luck causes Risk causes Age Duration on HPN Age at Onset of HPN Number of nights feeding
*Po0:05. **Po0:01.
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.
Table 2
0.13 0.12 0.36** 0.48** 0.17 0.08 0.02 0.18 0.03 0.05 0.36** 0.09 0.14
3
0.29* 0.01 0.02 0.15 0.11 0.14 0.15 0.01 0.47** 0.09 0.36* 0.09
4
0.22 0.23 0.09 0.11 0.07 0.14 0.15 0.18 0.04 0.06 0.14
5
7
8
9
10
11
12
13
14
15
0.59** 0.05 0.05 0.05 0.10 0.05 0.07 0.05 0.06 0.18 0.18 0.12 0.03 0.14 .06 0.03 0.10 0.19 0.58** 0.35** 0.25 0.06 0.10 0.07 0.07 0.11 0.09 0.14 0.11 0.24 0.29* 0.04 0.20 0.12 0.17 0.01 0.05 0.04 0.10 0.22 0.12 0.05 0.14 0.92** 0.40** 0.19 0.13 0.07 0.09 0.18 0.24 0.01 0.08 0.02 0.12
6
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Table 3 Regression analysis testing the significance of change in explained variance on emotional representations. Variable
R
Adj R2
R2 change
F change
df
P
B
Personal control Illness coherence
0.41 0.53
0.16 0.26
0.17 0.11
11.99 9.10
1, 58
0.001 0.004
0.43 0.34
A further interesting finding concerns the result that patients who were on HPN for longer than 5 years reported a stronger belief that the condition made increased sense for the patient, despite the attendant difficulties that being on HPN for longer can bring. It is therefore likely that the broad clinical observation that patients who are on HPN for longer tend to do better emotionally than patients with a shorter treatment duration3,19 results from the association between duration and an increased sense of illness coherence. Results also demonstrated that patients with vascular occlusion held significantly stronger beliefs that they would experience similar events in the future when compared with patients with IBD and the mixed category. While their emotional representation scores were higher than the other two groups, this did not reach statistical significance. Nonetheless, these patients with vascular occlusion are likely to demonstrate increased anticipatory anxiety as beliefs about future-oriented threat tend to be crucially involved in the development and maintenance of clinically relevant anxiety states. HPN patients when compared with previously published data from SSc, chronic pain and psoriasis were doing poorer emotionally, reported more symptoms, had less personal control but higher illness coherence. Given the importance of both personal control and illness coherence in emotional outcome found in the current study, ways of preserving illness coherence and increasing personal control for HPN patients deserves investigation. It is important to recognize that emotional representations are not necessarily synonymous with diagnostic categories of dysthymia, major depression or anxiety disorders. Indeed recent research has suggested that over one third of HPN patients have levels of anxiety and over one quarter levels of depression, of sufficient severity to be classified as clinically significant cases.20 Whilst the majority of patients will not meet diagnostic criteria, a significant additional number will be experiencing adverse emotional representations as they strive to adjust to their condition and
its treatment. Such levels of distress, whilst perhaps not fully warranting a diagnostic category are nonetheless difficult to negotiate and challenge for patients and their families and are likely to significantly interfere with treatment and wellbeing. While the number of patients participating in the study was higher than previous studies3,19 the overall response rate of patients from the possible participant pool agreeing to participate was somewhat lower. Unlike other studies we did not send out reminders to patients, which is likely to have influenced the numbers of patients participating. However, patients were broadly similar in terms of age, age at onset, presence of a stoma and duration on HPN so we can be quite confident about generalizing these finding to the larger pool of HPN patients under our care. There is a need for further investigation of mediating factors not simply as it pertains to patients but also in relation to key family members. There is indeed burgeoning evidence that carers representations in other chronic and stigmatizing conditions can either help or hinder patients. Moreover, divergence in beliefs about chronic and stigmatizing conditions between patients and their spouses tends to be associated with depression in patients and worry in their spouses.16 Further research is also required to evaluate the effects of specifically targeting psychological interventions to patients implicit model of their condition, which has begun to be evaluated in other chronic conditions.21 In conclusion, the current study has demonstrated a central role for illness coherence and personal control in moderating the emotional representations of patients on HPN. Knowledge of the importance of these factors requires an approach to provision of information that is appropriate to the needs of the individual patient and is constantly assessed and delivered in a manner that promotes both coherence and personal control.22 The relationship between psychological factors, disease and illness therefore become critical for optimizing standard treatment and for accurately evaluating treatment outcomes.
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Acknowledgments Our thanks to the patients who agreed to participate in this study.
11.
12.
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