Psychological problems following ICU treatment*

Transcription

1 Anaesthesia, 2001, 56, pages 9±14 Psychological problems following ICU treatment* P. Scragg, 1 A. Jones 2 and N. Fauvel 3 1 Chartered Clinical Psychologist, Sub-Department of Clinical Health Psychology, University College London, Gower Street, London WC1E 6BT, UK 2 Clinical Psychologist, Brain Injury Rehabilitation Trust, Thomas Edward Mitton House, Belvoir Avenue, Emerson Valley, Milton Keynes MK4 2JA, UK 3 Consultant Anaesthetist and Intensivist, Magill Department of Anaesthesia, Critical Care Medicine and Pain Management, Chelsea and Westminster Hospital, London SW10 9NH, UK Summary Treatment in an intensive care unit can be stressful and may leave patients with persisting psychological symptoms that impair quality of life. This postal questionnaire study of patients who had previously been treated in a general adult intensive care unit showed that 38 (47%) of 80 patients who returned fully completed questionnaires reported clinically significant anxiety and depression as measured by the Hospital Anxiety and Depression Scale. Thirty (38%) reported significant symptoms of post-traumatic stress disorder, of whom 12 (15%) reached levels consistent with a diagnosis of full post-traumatic stress disorder as measured by the Trauma Symptom Checklist 33 and the Impact of Events Scale. We describe a new measure of psychological distress specifically related to the experience of intensive care management, the Experience after Treatment in Intensive Care 7 Item Scale, and compare it to the other scales. The Experience after Treatment in Intensive Care 7 Item Scale shows that at least a proportion of the posttraumatic stress reported was directly attributable to the experience of treatment in the intensive care unit. Keywords Critical care: psychological outcome. Stress disorders: post-traumatic; diagnosis.... Correspondence to: Dr N. Fauvel *Study undertaken at the Chelsea and Westminster Hospital Accepted: 17 June 2000 Treatment in an intensive care unit (ICU) is both stressful and psychologically traumatic for patients. A recent Australian study compared the self-reported quality of life of survivors of critical illness to a group randomly chosen from the local community [1]. This study found that survivors of critical illness have poorer perceived health and are more anxious than the general population. Although interesting and clinically useful, this study did not use recognised measures of mental disorder. Many mental disorders can arise after traumatic and stressful events, including anxiety, depression and posttraumatic stress disorder (PTSD). The symptoms of PTSD cluster into three groups. The first two are specific to the traumatic aetiology of the disorder, re-experience of the trauma and avoidance of stimuli likely to remind the patient of the trauma. Re-experience of the trauma includes intrusive memories and vivid images of the event during waking hours, which can be of such intensity that the person loses contact with their current surroundings. Nightmares of the trauma are common. Avoidance of stimuli likely to remind the patient of the trauma include avoiding conversation, places, people and activities associated with the trauma. The third symptom group consists of hyperarousal (e.g. difficulty with sleeping, concentration and irritability) and this cluster commonly occurs in other psychological disorders as well as in PTSD. Anxiety or depression may occur because of the critical illness rather than the traumatic event itself. For example, depression after ICU discharge may be due to the frustration of continuing ill health, disability or inability to work, rather than the actual injury itself. The incidence of PTSD in patients discharged from ICU was examined by Schelling [2]. This questionnaire study of 87 survivors of critical illness used a self-report scale of PTSD, the PTSD 10 Inventory [3]. Eighty of the questionnaires were returned to the investigators and the incidence of PTSD was found to be 27.5%. By comparison, the prevalence of PTSD in the general population is 2.7% for women and 1.2% for men [4]. In Schelling's study, the duration of ICU admission q 2001 Blackwell Science Ltd 9

2 P. Scragg et al. Psychological problems following ICU treatment Anaesthesia, 2001, 56, pages 9±14 was related to the PTSD 10 Inventory score. While there may be an increased incidence of PTSD in survivors, identifying whether any PTSD symptoms can be directly attributed to the ICU experience remains unexplored. Therefore, our study aimed to identify psychological distress including anxiety, depression and PTSD, using three established measures of mental disorder, amongst patients who have been treated in a general ICU. It sought to establish whether there is any significant effect of gender, age, duration of ICU stay or time since discharge from ICU on post-icu psychological distress. Using a new measure designed specifically for the study, we also sought to ascertain if any traumatic stress symptoms are directly linked to the ICU experience itself. Methods The study was approved by the Chelsea and Westminster Hospital Ethics Committee. All ICU survivors between 1 October 1995 and 1 October 1997 were identified from the hospital computer records. Patients suffering from cerebral trauma, and accidental or non-accidental injury were not studied so that the chances of PTSD from causes other than ICU management were reduced. All patients who were only briefly monitored in the High-Dependency Unit following routine operations (without complications) were also excluded. The general practitioner (GP) of each identified survivor was telephoned to check if there was any reason why it would be inappropriate to send the questionnaire (e.g. recent death of the patient). Measures A pack, including an explanatory letter, composed of four questionnaires was assembled. Part of each questionnaire is shown as an example in Appendix A. The questionnaires were all self-reported, requiring no help. Trauma Symptom Checklist-33 (TSC-33) [5] measures symptoms found in psychologically traumatised individuals. Each TSC-33 item (e.g. `Nightmares', `Feeling things are ``unreal'' ', `Feeling that you are not always in your body', and `Feeling tense all the time') is rated according to its frequency over the preceding 2 months, using a four-point scale ranging from 0 (never) to 3 (often). The Hospital Anxiety and Depression Scale (HADS) [6] is widely used in hospital settings as a screening instrument for anxiety disorders and depressive illnesses. It does not contain questions pertaining to somatic complaints, making it is less likely to be confounded by the direct effects of medical conditions. Both of the subscales (one for depression and one for anxiety) have threshold scores (. 8) above which a clinical disorder is likely. Scores from the two subscales may be combined to produce an HADS full-scale score. A full-scale score of over 12 is indicative of a clinical disorder. The Impact of Events Scale (IES) [7] is widely used for measuring post-traumatic stress. It has two subscales, the first pertaining to re-experiencing the trauma (e.g. nightmares) and the second to avoiding situations and thoughts that are associated with the trauma. Previous research [8] has shown that scores on the IES are skewed; patients who are not psychologically traumatised score close to zero. Scores on the IES subscales for intrusions and avoidance have been stratified as follows: 8 or less: mild or absent symptoms, 9219: medium level of symptoms and, 20 or more: high levels of symptoms [9±10]. Scores above 30 on the IES indicate severe psychological trauma symptoms and individuals scoring in this range are likely to meet diagnostic criteria for PTSD [11]. The Experience after Treatment in Intensive Care 7 Item Scale (ETIC-7) is a seven-item questionnaire designed specifically for this study to measure post-traumatic stress directlyassociated with the patient's experience of the ICU. To construct the questionnaire, we examined the criteria for PTSD specified in the Diagnostic and Statistical Manual of Mental Disorders [12]. This is a standard reference of psychiatric classification that is commonly used for diagnosis and research. We identified seven criteria that could be used to create questionnaire items that specifically reflect experience of ICU treatment. These criteria come from the trauma re-experiencing and trauma-stimuli avoiding symptom clusters. We did not include criteria related to hyperarousal symptoms because it was not possible to word questionnaire items specifically to reflect experience of ICU treatment. The order of questionnaires in the pack was TSC-33, HADS, ETIC-7 and finally IES. The reason that the most widely used measure of post-traumatic stress (IES) was placed immediately after the new questionnaire (ETIC-7) was so that the questions specifically related to intensive care in the ETIC-7 would `cue' the subject to think about their ICU experience as they subsequently completed the IES. Statistical analysis We compared the age, gender and duration of stay in the ICU of those subjects who returned the questionnaire with those who did not. From the returned questionnaires, data from individual items were entered into the Statistical Package for the Social Sciences (SPSS) for Windows (Release 6.1). We assessed the internal consistency of the ETIC-7 by calculating Cronbach's alpha [13]. We normalised any skewed score distributions using a square root transformation. In order to examine whether the ETIC-7 was a valid measure of post-traumatic stress, we correlated the ETIC-7 scores with the scores of the TSC-33, HADS and IES using Pearson product-moment correlation. We also used Pearson product-moment correlation as a test for association between questionnaire scores and three variables: age, duration of stay in the ICU and time since discharge from the ICU. Finally, we employed multiple regression to 10 q 2001 Blackwell Science Ltd

3 Anaesthesia, 2001, 56, pages 9±14 P. Scragg et al. Psychological problems following ICU treatment Table 1 Age and sex of sample sent questionnaire pack (numbers of individuals). Age band (years) examine whether gender, age, duration of stay in ICU, and time since discharge from the ICU might predict psychological distress as measured by the HADS, IES, TSC-33 and the ETIC-7. Results Responders Non-responders Male Female Male Female 19± ± ± and over Total n ˆ Sample demographics According to the hospital computer records, 439 patients were treated by the Chelsea and Westminster Hospital ICU between 1 October 1995 and 1 October Two hundred and twenty-two patients were suitable for the study but this was reduced to 142 after the GP had been contacted. Twelve patients had moved home and could not be contacted and a further 68 had died. No patients were deemed inappropriate by GPs for emotional or psychological reasons. Of the 142 questionnaire packs sent, 86 were returned (61%); 80 (56%) of these contained usable data (i.e. complete TSC-33, HADS and ETIC-7 but three incomplete IES questionnaires). Of the 80 returns, 42 were completed by men and 38 by women. The age of the sample ranged from 19 to 90 years, with a median age of 57.1 years. Table 1 shows the numbers of male and female responders and nonresponders stratified by age. The distribution of duration of ICU stay for the 80 patients is shown in Fig. 1; the majority of patients stayed for two or less days (33 subjects had stayed in ICU for up to 24 h and 24 subjects had stayed up to 48 h). Level of reported psychological distress The measures of anxiety and depression from the HADS were normally distributed. The IES, TSC-33 and ETIC-7 were all positively skewed and the square-root transformations were used for the subsequent correlation calculations. The mean score on the TSC-33 was 27.4 with a standard deviation (SD) of On the HADS scale, 24 (30%) of the sample scored above 8 on the depression subscale and 34 (43%) scored above 8 on the anxiety subscale. On the HADS full scale, 38 (47.5%) of the sample scored above 12. Table 2 gives the scores for the IES intrusion and anxiety Number of Patients Length of ICU stay (days) Figure 1 Distribution of duration of intensive care unit (ICU) stay (days). q 2001 Blackwell Science Ltd 11

4 P. Scragg et al. Psychological problems following ICU treatment Anaesthesia, 2001, 56, pages 9±14 Table 2 IES subscale scores (number of individuals (% of n ˆ 77)). IES intrusions IES avoidance # 8 53 (68%) 54 (70%) 9±19 18 (23%) 14 (18%) $ 20 6 (8%) 9 (12%) subscales. On the IES full scale (n ˆ 77, three questionnaires were incomplete for the IES), 12 (15.6%) of the sample (eight women and four men) scored above 30. Six were under the age of 35 years (four female and two male), three were middle-aged (two male, one female), and three were over 65 years (all female). Two of the individuals had past medical histories of psychiatric disorder. All 12 patients who scored above 30 on the IES also scored above the threshold scores on the HADS. Scores on the ETIC-7 range from zero (indicating no symptoms) to 18. The median score was 2 and the mode was zero. Fifty-six (71%) of the sample scored 4 or less, 15 (19%) scored between 5 and 8, and eight (10%) scored between 9 and 18. Cronbach's alpha for the ETIC-7 was Table 3 shows the correlations between the ETIC-7 and the IES, HADS, and TSC-33. Predictors of symptoms There was a significant correlation between the ETIC-7 score and time since discharge (r 2 ˆ 0.053, p ˆ 0.04) and a significant negative correlation between the ETIC-7 score and age (r 2 ˆ 0.048, p ˆ 0.05). There was no significant correlation between the ETIC-7 score and duration of stay in ICU. No significant correlations were found between age, duration of stay in ICU or time since discharge from ICU and the HADS total score, IES total score or TSC-33 total score. In the regression analysis, higher ETIC-7 score was associated with lower age [b ˆ , SE ˆ 0.01, t ˆ , p ˆ 0.04] and longer time since discharge [b ˆ 0.23, SE 0.02, t ˆ 2.1 p ˆ 0.04]. The sizes of the effects were similar (F (4, 74) ˆ 2.87, p ˆ 0.03) for both age and time since discharge. There was no effect of Table 3 Pearson correlations for the ETIC-7 with the IES, HADS and TSC-33. Scale r p IES total 0.5 # IES intrusions 0.57 # IES avoidance 0.39 # HADS total 0.54 # HADS anxiety 0.61 # HADS depression 0.37 # TSC-33 total 0.56 # gender or duration of stay on the ETIC-7 score. Age, gender, duration of stay and time since discharge were not significant independent predictor variables for the HADS total score, IES total score or TSC-33 total score. Discussion The response rate, 80 (56% of the total sample) usable questionnaires out of a sample of 142, is typical for selfadministered questionnaire mail surveys and generally considered adequate for analysis [14]. This postal questionnaire study of discharged ICU patients found high rates of psychological distress using measures of depression, anxiety and post-traumatic stress. Thirty-eight (47%) of the 80 patients who returned complete questionnaires scored more than 12 on the HADS full scale. They warrant expert assessment for depression or anxiety as this score is above `disorder likely' threshold. In comparison, Ormel [15] found that 24.5% of a large sample of chronic medical patients scored above 12 on the HADS. In common with most psychological screening instruments, the sensitivity of the HADS is excellent (100% in one study of medical patients [16]) but the specificity is less impressive (ranging from 73% in one study [6] to 94% in another [17]). In our patients, the mean score on the TSC-33 was 27.4, which can be compared with the mean of 17.8 (SD 9.5) for a non-clinical sample published by Elliot and Briere [18]. This suggests that, on average, discharged ICU patients reported more psychological symptoms associated with traumatic stress than other individuals. The IES scores suggest that approximately 30% of the discharged ICU patients are reporting post-traumatic stress symptoms with 15% (eight women and four men) reporting severe psychological trauma symptoms suggestive of PTSD. The sex ratio of these 12 patients suffering from PTSD is consistent with epidemiological data showing a sex ratio of 2 : 1 female/male [4, 19, 20]. The fact that only three of the 12 with likely PTSD were over 65 years of age is consistent with findings that younger people are at slightly greater risk [20]. The seven items of the ETIC-7 were found to have good internal consistency (Cronbach's alpha ˆ 0.84). Such high internal consistency is a marker of reliability, indicating that the seven items seem to measure different aspects of a single construct or concept. The ETIC-7 was derived from official Diagnostic and Statistical Manual Criteria for PTSD and so should be valid. Second, validity is reflected by agreement (i.e. correlation) between a new measure and other previously validated measures. For example, because PTSD is an anxiety disorder, a new measure of PTSD should relate to measures of anxiety (concurrent validity). Such associations were found in this study. The ETIC-7 scores showed stronger correlations with the IES and TSC-33 scores, and HADS anxiety scores than with the HADS depression scores. Finally we consider 12 q 2001 Blackwell Science Ltd

5 Anaesthesia, 2001, 56, pages 9±14 P. Scragg et al. Psychological problems following ICU treatment that these correlations, together with the high internal consistency of the ETIC-7, suggests that the total score of the ETIC-7 can be used as a measure of post-traumatic stress directly related to ICU. We employed multiple regression to examine if age, sex, duration of stay and time since discharge were related to levels of psychological distress. When the ETIC-7 score alone was used as the dependent variable, age and time since discharge were significant independent predictors: lower age and longer time since discharge were associated with higher ETIC-7 score. However, we found no significant independent predictor variables when the IES, HADS and TSC-33 scores were the dependent variables. Since the items of the ETIC-7 were written specifically to reflect post-traumatic symptoms from the ICU and, as noted above, seem to be a reasonably valid measure, this may reflect the greater sensitivity of the ETIC-7. The age effect in the multiple regression confirms that younger people are more susceptible to PTSD. The time since discharge effect suggests that the greater the length of time since leaving the ICU, the greater the distress as measured by the ETIC-7 and implies delay in onset of PTSD symptoms. In the immediate months after discharge, preoccupation with regaining physical health may distract from dwelling on the psychological impact of the ICU experience. This study, in keeping with the general PTSD research literature, suggests that only a minority of ICU survivors meet formal criteria for PTSD diagnosis. Nevertheless, it is clear that many may experience lower levels of PTSD (a `partial PTSD') while others experience strikingly high levels of anxiety and depression. Certain limitations of the study should be noted. Firstly, self-reported questionnaires often have excellent sensitivity but weaker specificity when compared with a structured psychiatric interview. Second, although the individuals who failed to return questionnaires appear to be similar in terms of basic demographics, it is possible that the current sample is not representative of the post- ICU population in general. For instance, post-icu patients with psychological problems might be more or less likely to have responded to the questionnaire than those without psychological problems. Finally, a larger sample may have allowed both better elaboration of predictive variables for psychological difficulties and allow further validation of our new ETIC-7 questionnaire. In conclusion, assessment and treatment of psychological distress in discharged ICU patients is needed because the prevalence of post-traumatic stress, depression and anxiety conditions appears to be high. At least a proportion of this psychological distress appears to be as a direct result of ICU treatment. The ETIC-7 questionnaire, specially designed for this study, appears to identify patients who are troubled or haunted by their experiences of ICU. This new questionnaire, while needing further study to establish reliability and validity, may prove to be a useful screening tool to identify patients possibly in need of emotional support following discharge from ICU. Acknowledgment We would like to thank Dr Pasco Fearon of the Department of Psychology, University College London, for statistical advice. References 1 Brooks R, Kerridge R, Hillman K, Bauman A, Daffurn K. Quality of life outcomes after intensive care: Comparison with a community group. Intensive Care Medicine 1997; 23: 581±6. 2 Schelling G, Stoll C, Haller M et al. Health-related qualityof life and posttraumatic stress disorder in survivors of the acute respiratory distress syndrome. Critical Care Medicine 1998; 26: 651±9. 3 Holen A, Sund A, Weisaeth L. Questionnaire for screening disaster victims. Acta Psychiatrica Scandinavica, 1989; 80: Stein MB, Walker JR, Hazen AL, Forde DR. Full and partial posttraumatic stress disorder: Findings from a community survey. American Journal of Psychiatry 1997; 154: 1114±19. 5 Briere J, Runtz M. The Trauma Symptom Checklist (TSC- 33): Early data on a new scale. Journal of Interpersonal Violence 1989; 4: 151±63. 6 Zigmund AS, Snaith RP. The Hospital Anxiety and Depression Scale. Acta Psychiatrica Scandinavia 1983; 67: 361±70. 7 Horowitz M, Wilner N, Alvarez W. The Impact of Event Scale: a measure of subjective stress. Psychosomatic Medicine 1979; 41: 209±18. 8 Briere J, Elliott DM. Clinical utility of the Impact of Events Scale: Psychometrics in the general population. Assessment 1998; 5: 171±80. 9 Eelsland S, Weisarth L, Sund A. The stress upon rescuers involved in an oil rig disaster, `Alexander L. Kielland' Acta Psychiatrica Scandinavica 1989; 355: S38± Hytten K, Hasle A. Fire fighters: a study of stress and coping. Acta Psychiatrica Scandinavica 1989; 355: S50±5. 11 Robbins I, Hunt N. Validation of the IES as a measure of the long-term impact of war trauma. British Journal of Health Psychology 1996; 1: 87±9. 12 American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, 4th edn. Washington, DC: American Psychiatric Association, Cronbach LJ. Coefficient alpha and the internal structure of tests. Psychometrika 1951; 16: 297± Barker C, Pistrang N, Elliott R. Research Methods in Clinical and Counseling Psychology. London: Wiley, Ormel J, Kempen G, Penninx B, Brilman EI, Beekman AT, VanSonderen E. Chronic medical conditions and mental health in older people: disability and psychosocial resources mediate specific mental health effects. Psychological Medicine 1997; 27: 1065± Silverstone PH. Poor efficacy of the Hospital Anxiety and Depression Scale in the diagnosis of major depressive disorder in both medical and psychiatric patients. Journal of Psychosomatic Research 1994; 38: 441±50. q 2001 Blackwell Science Ltd 13

6 P. Scragg et al. Psychological problems following ICU treatment Anaesthesia, 2001, 56, pages 9±14 17 Barkczak P, Kane N, Andrews S, Clay JC, Bretts T. Pattern of psychiatric morbidity in a genitourinary clinic: a validation of the Hospital Anxiety and Depression Scale (HADS). British Journal of Psychiatry 1988; 152: 698± Elliot DM, Briere J. Sexual abuse trauma among professional women: validating the Trauma Symptom Checklist-40 (TSC-40). Child Abuse and Neglect 1992; 16: 391±8. 19 Kessler RC, Sonnega A, Bromet E, Hughes M, Nelson CB. Post-traumatic stress disorder in the National Comorbidity Survey. Archives of General Psychiatry 1995; 52: 1048± Breslau N, Davis GC, Andreski P, Peterson EL, Schultz LR. Sex differences in post-traumatic stress disorder. Archives of General Psychiatry 1997; 54: 1044±8. Examples items from the IES Below is a list of comments made by people after stressful life events. Please read each item, indicating how frequently each comment was true for you during the past seven days. If they did not occur during that time, please circle the `not at all' answer Please circle answer closest to the way you feel Not at all Rarely Sometimes Often Any reminder brought back feelings about it I stayed away from reminders about it Pictures about it popped into my mind I tried not to think about it Appendix A The Trauma Symptom Checklist-33 (TSC-33), Impact of Events Scale (IES) and Hospital Anxiety and Depression Scale (HADS) are copyright and we give examples together with details of where they may be purchased. We are happy for the ETIC-7 to be freely reproduced. Example items from the TSC-33 How often have you experienced each of the following in the last 2 months? Both the IES and the HADS may be purchased from The NFER-Nelson Publishing Company Ltd, Darville House, 2 Oxford Road East, Windsor, Berks. SL4 1SF, UK. The questionnaires are supplied with scoring keys and guidance on interpreting the scores. Experience after Treatment in Intensive Care 7 Item Scale (ETIC-7) Below is a list of problems that people sometimes experience after treatment in Intensive Care. Please read each statement and circle the answer that best describes how often that problem has bothered you in the last 2 months. Please circle answer closest to the way you feel Not at all Rarely Sometimes Often Please circle answer closest to the way you feel Not at allrarelysometimesoften Insomnia (trouble getting to sleep) Feeling isolated from others `Flashbacks' (sudden, vivid, distracting memories) Anxiety attacts Nightmares `Spacing out' (going away in your mind) A copy of the complete TSC-33 may be obtained by purchasing Stamm BH. Measurement of Stress, Trauma, and Adaptation. Maryland, USA: Sidran Press, Example items from the HADS Read each item and place a firm tick in the box opposite the reply which comes closest to how you have been feeling in the past week. Tick one box in each section. I get sort of frightened feeling as if something awful is about to happen: Very definitely and quite badly A Yes, but not too badly A A little, but it doesn't worry me A Not at all A I have lost interest in my appearence: Definitely A I don't take as much care as I should A I may not take as much care A I take as much care as ever A 1. Have you had upsetting thoughts or images about your time in the Intensive Care Unit that came into your head when you didn't want them to? Have you experienced `flashbacks' which make you feel as if you are back in the Intensive Care Unit? Have you felt upset when you were reminded of your stay in the Intensive Care Unit? Have you had bad dreams or nightmares about your time in the Intensive Care Unit? When reminded of your stay in the Intensive Care Unit, does it make you feel anxious or unwell (for example, heart racing or thumping, nausea, sweating)? Have you tried not to think about, talk about, or have feelings about your time in the Intensive Care Unit? Have you tried to avoid activities, people or places that remind you of the Intensive Care Unit (for example, doctors appointments, visiting hospital or television programs about hospitals)? Do you have any comments that you would like to add? 14 q 2001 Blackwell Science Ltd