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ORIGINAL ARTICLE
Year : 2007  |  Volume : 24  |  Issue : 2  |  Page : 45-50 Table of Contents   

Randomized controlled study of CBT in bronchial asthma


1 Department of Chemical Psychology NIMHANS, Bangalore., India
2 Department of Chest Medicine, St. John's Medical College Hospital Bangalore., India
3 Department of Bio-statistics, National Institute of Mental Health and Neuro Sciences (NIMHNAS), Bangalore., India
4 Department of Clinical Psychology, National Institute of Mental Health and Neuro Sciences (NIMHNAS), Bangalore., India

Correspondence Address:
Naveen Grover
Department of Clinical Psychology, NIMHANS, Banglore-29.
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0970-2113.44209

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   Abstract 

The aim of the present study was to find out efficacy of cognitive behavior therapy, as an adjunct to standard pharmacotherapy, in bronchial asthma. In a random­ized two-group design with pre-and post assessments, forty asthma patients were randomly allotted to two groups: self management group and cognitive behavior therapy group. Both groups were exposed to 6-8 weeks of intervention, asthma self management program and cognitive behavior therapy. Assessment measures used were-Semi structured interview schedule, Asthma Symptom Checklist, Asthma di­ary, Asthma Bother Profile, Hospital Anxiety & Depression Scale, AQLQ and Peak Expiratory Flow Rate. Within group comparison showed significant improvement in both groups at the post assessment. Between group comparisons showed that CBT group reported significantly greater change than that of SM group. Cognitive behavior therapy helps in improving the managment of asthma.

Keywords: CBT, QOL, Psychological, Asthma, Management


How to cite this article:
Grover N, D'Souza G, Thennarasu K, Kumaraiah V. Randomized controlled study of CBT in bronchial asthma. Lung India 2007;24:45-50

How to cite this URL:
Grover N, D'Souza G, Thennarasu K, Kumaraiah V. Randomized controlled study of CBT in bronchial asthma. Lung India [serial online] 2007 [cited 2019 Oct 18];24:45-50. Available from: http://www.lungindia.com/text.asp?2007/24/2/45/44209


   Introduction Top


Bronchial asthma causes considerable financial burden to nations and to individuals. Financial constraints caused due to expense of treatment and curtailed family activities may lead to break down and disintegration of families [1] . Presence or fear of symptoms may cause asthma patients to avoid physical activities and social situations they might otherwise enjoy. It is difficult to arrive at a psychiatric diagnosis of depression in asthma, although self-reports of the condition are common [2] . Chronic nature of the disease and unpredictability and intensity of acute episodes can substanially lower patient's health-related quality of life (HRQL) [3] .

From 1980s onwards, a number of self-management programs have been developed and evaluated for both pediatric and adult asthma that integrate asthma education with drug therapy as a part of the program [4],[5],[6] . Despite emerging consensus about the role of psychological factors in asthma morbidity [7] , there are very few studies [8],[9] addressing psychological factors in management of adult asthma. In India, Grover et al [10] , in a preliminary study, addressed psychological factors in management of asthma and found that cognitive behavior therapy was effective in improving anxiety, depression, quality of life and management of asthma. Present study is an improvement and replication of previous study by Grover et al [10] .


   Material and Methods Top


Aim of the present study was to evaluate efficacy of cognitive behavior therapy (CBT) in management of bronchial asthma. Specific objectives were to find out efficacy of CBT in dealing with asthma related symptoms in reducing distress and in enhancing quality of life of patients with asthma.

A randomized before and after-intervention two-group design was adopted. A sample of 40 patients meeting inclusion and exlusion criteria was taken up from Chest Medicine Out Patient Department, St. John's Medical College and Hospital, Bangalore.

Inclusion Criteria

  • Individuals with diagnosis of asthma [11]
  • Individuals in age range of 18-45 years
  • Individuals having at least 2-years duration of illness
  • Individuals with working knowledge of Hindi/ English


Exclusion Criteria

  • Patients with other medical conditions involving breathing difficulties
  • Presence of other medical conditions such as coronary heart disease, diabetes, or hypertension
  • Patients with clinical history of psychiatric illness
  • History of exposure to structured psychological intervention


Tools Used

Semi-structured Interview Schedule (SSIS) : This was developed to obtain scociodemographic data, clinical history and asthma specific informaiton.

Asthma Symptom Cheklist (ASC) : It measured nature and severity of various symptoms generally seen in asthma and patient's emotional reactions to asthma symptoms. It has 16 items with severity to be measured on 1 4-point scale. High score indicates more severity of symptoms.

Asthma Diary (A [5] ) : Patients were provided with asthma diary to record asthma symptoms and use of quick relief medications. On each visit, information recorded was checked with patient and missing information was elicited. Patients were to record a numeric value (score) for each symptom everyday based on operational definitions provided in diary.

Asthma Bother Profile (ABP [12] ) : Asthma bother profile items are of two kinds : 15 bother items and 7 management items. Subjects respond on a six-point scale. High score in bother section indicates more bother. Seven "management items" assess patient's confidence of asthma knowledge, perception of quality of care and confidence in their ability to manage an asthma attack. High score on these items indicates poor asthma management.

Hospital Anxiety & Depression Scale (HADS [13] ) : HADS is a reliable, valid and practical tool for identifying anxiety and depresson in medical patients. It is a 14 items scale scored on a 4-point scale. High score indicates more severity of symptoms.

Asthma quality of life questionnaire (AQLQ [3] ) : AQLQ contains 32 items in four domains : activities domain, asthma symptoms domain, emotional functions domain, and environmental exposure domain. Patients are asked to indicate how they have been during the last two weeks on a 7-point scale. Lower score indicates greater impairment in quality of life.

Peak Expiratory Flow Rate (PEFR) : It was used as an outcome measure in this study. It was measured with the help of mini Wright peak flow meter in every session. The patient blew three times in the meter. Best of three values was recorded as patient's PEER in each session.

Procedure

Ethics
: Protocol of the study was presented to and approved by Ethical Committees of NIMHANS and SJMCH Bangalore. Nature and procedure of study was explained to each patient. Written informed consent of patients wastaken. Patients were informed that they could opt out of study, if they wished so, at any point of time without giving any reason.

Data Collection : It was done over 23 months, from Nov. 1999 to Oct. 2001. A total of 190 patients were contacted. Following is the break up of number of cases that were contacted :

Total contacted - 190

Did not satisfy age criteria - 38

Did not satisfy language criteria - 23

Other medical conditions - 5

Outside Bangalore - 11

Refused to participate - 20

Wanted to enroll on some other time - 20

No contact after the first contact - 15

Left the city - 6

Dropout - 12

Completed the study - 40

Assignment of patients to two groups : After informed consent and baseline assessment, patients were randomly allotted, using random number table, to two groups­self-managment (SM) group and cognitive behaviour therapy (CBT) group. In addition to standard medical management, SM group was provided with asthma self­managment program (ASMP) and CBT group was provided with cognitive behaviour therapy. Post-intervention assessment was carried out in both groups after 6-8 weeks, at completion of interventions. Patients were not using any antidepressant/antianxiety medication during the intervention.

Details of Therapeutic Procedures

Asthma Self-Management Program (ASMP)
: SM Group

Program was based on information obtained from National Institute of Health, U.S.A. [14],[15] , modified to suit present population, as well as from literature on asthma. Program was tailored to individual needs based on assessment of the patient. Program was conducted in 10 sessions of 1-hour each spread over 6-8 weeks duration. It included :

a) Asthma education : Discussion on nature of asthma and asthma medications and teaching of skills to use inhalers, spacer and PEF meter.

b) Training in self-managment behaviour such as identification and avoidance of triggers. Training of skills involved-Breaking task into smaller parts, modeling to show correct way to do task, differential reinforcement for correct and incorrect Behaviour, looking at improvement as a gradual process, and emphasis on over learning and homework assignments.

c) Guided self-management : Guided self-managment plan included-daily dose of preventive therapy (controller medication), name and dose of bronchodilator that should be taken to relieve symptoms (reliever medication), advice on how to recognize signs that suggest deteriorating control, advice on how to treat worsening asthma, including advice about how and when to seek medical attention.

d) Self-monitoring : Self-monitoring was an inherent component of ASMP. Patients were monitoring their symptoms and use of medication in an asthma diary.

e) Discussion on negative emotions and asthma : Brief discussion focused on experience of negative emotions due to asthma and effect of general stress on asthma illness.

f) Breathing exercises [16] : Breathing exercises were taught, checked and corrected in each session. Patients were provided with booklet on breathing exercises, which clearly showed procedure of breathing exercises and they were asked to practice it at home everyday.

g) Behavioral counselling to significant others : Patient's significant others were provided with asthma education and disussions were carried out to identify and modify their inappropriate reactions to patient's illness.

Cognitive Behaviour Therapy (CBT) : CBT Group

Cognitive behavior therapy consisted of 15 sessions of 1-hr each spread over 6-8 weeks duration. Therapy was tailored to individual needs based on assessment of patients. It contained following components :

a) ASMP : Details of ASMP are given under SM l group.

b) Cognitive restructuring [17] : Cognitive restructuring involved identification and restructuring of negative thoughts, feelings and beliefs about themselves ("I am letting others down"; "I am trouble to others"; "I am loosing control over myself'), about their illness ("I have an illness without cure"; "Having asthma is a sign of weakness"; "I am going to get attack at crucial times") and maladaptive cognitive appraisal of the potential stressores.

c) Skills training : Focus of skills training was on two kinds of skills -problem solving skills training and social skills (assertion) training.

Problem solving skills training : Problem solving is a means of identifying problem and looking for feasible solutions. Patients were taught various steps involved in problem solving and were encouraged to apply these skills to problems directly linked to triggering asthma symptoms such as suggesting for hiring a personal vehicle on a sharing basis to go for work (to avoid dust), suggesting to change sitting arrangement of smokers and non-smokers at work place.

Social skills (assertion) training : Patients were trained to communicate, without fear or denial, about their asthma with others. Skills were provided to ask people, at home and/or at work, not to smoke in their presence or to ask spouse not to use strong perfumes while together. Focus of skills training was also on teaching patients how to get help from others and to minimise effect of asthma on their interpersonal relationship.

d) Imaginary rehearsal : Patients were provided with opportunity to rehearse skills in imagination in sessions. Similar exercises were given as homework assignments.

e) Role-plays : Role-plays were carried out in the sessions to practice various skills taught in therapy. It involved patients engaging in role-play with therapist of various situations in which they faced problems Some of the situations involved were : communicating with doctor, getting an attack, problem at work place, communicating with spouse and problems at interpersonal relationships.

f) Weekly activity schedule : Main focus was to increase patient's involvement in adaptive behavior (e.g. physical exercise) and to decrease involvement in maladaptive behavior (e.g. smoking). It involved identifying a target activity, identifying present involvement in activities, setting up goals, reviewing and modification of goals.

g) Homework assignments : Homework assignments were given to patients to practice skills learned in sessions. It included involving in imaginary rehearsal and role­ plays at home. Homework assignments were reviewed at beginning of each session and further assignments were given at the end of each session.


   Statistics Top


Analysis of data was done using Statistical Package for Social Sciences 10.0 Version for Windows (SPSS 10.0). On AQLQ, a change of 0.5 was taken as "minimal important differnce"; a change of 1.0 was taken as "moderate change" and a change of 1.5 and above was taken as "large change" in quality of life [18] . Data from asthma diary was analysed using repeated measures Analysis of Variance (ANOVA). Scores for asthma symptoms were calculated by taking average score of each week for each symptom separately. Similarly, scores for quick-relief medication were calculated by taking average number of puffs used in each week. Within group comparison was made to see improvement over the weeks by comparing each week's average score with baseline (week 1) average score. Group's average PEFR score was calculated for each session. Improvement in groups' average PEFR scores over sessions is representedon a "line graph."

Analysis to find out efficacy of intervention was carried out on two lines : within-groups comparison and between-groups comparison. Before-intervention scores were compared with after-intervention scores within groups, using paired t-test, to evaluate improvement in each group. Mean change (after-intervention score-before-­intervention score) scores were compared between groups, using independent t-test, to evaluate efficacy of CBT over ASMP. Level of significance was taken as .05 and all comparisons were made under two-tailed hypothesis. Criteria of minimal important change was used for within groups analysis on AQLQ [18] . However, Juniper et al [8] do not favor the use of criteria of minimal important change for between groups analysis. Thus, between groups analysis was made from mean change scores, as done in the case of other variables.


   Results Top


To find out homogeneity of groups, two groups were compared on sociodemographic variables, clinical variables and on baseline assessment scores using t-test (in case of continuous variables) and Chi-square test (in case of dichotomous variables). Both groups were comparable on sociodemographic and clinical variables such as age, sex, marital status, education, religion, occupation, family history of asthma, work loss, hospital admission, duration of illness and emergency room visits. Groups were not comparable on baseline assessment on ABP-B (p<.01), ASC (p<.05) and HADS (p<.01).

In within groups comparison, both groups patients reported significant improvement in asthma symptoms [Table 1] and [Table 2], asthma bother, anxiety, depression [Table 2] and asthma quality of life [Table 3]. Thus, it is clear that, CBT as well as ASMP were effective in improving management of asthma.

In [Table 2], week 1 score was taken as the baseline value and a pair-wise comparison was carried out with remaining 5 weeks scores. There was significant reduction in wheezing (p<.01). In the similar way there was significant reduction in breathlessness (p<.01), chest tightness (p<.01), cough (p<.01), and use of quick relief medication (p<.01). Results were similar in both groups from asthma diary.

The results from the between groups comparison [Table 4] showed that CBT group patients reported more improvement in asthma symptoms (p<.01), asthma bother (p<.05), anxiety, depression (p<.01) and in asthma quality of life (p<.05) than that of SM l group patients. There was a trend for greater improvement favoring CBT group on asthma diary and PEER [Figure 1].

Follow-up analysis : Follow-up was not a planned phase in present study. It was done for as many patients as possible. Follow-up, after 12-weeks of post-interventiion assessment, could be possibe for 17 patients, 7 from SM group and 10 from CBT group. Within groups analysis was carried out comparing post-pintervention assessment and follow-up asssesment scores using paired t-test. Sm group patients maintained their improvement over 12-weeks follow-­up. CBT group patients, on the other hand, continued to improve further on bother (p<.01), anxiety and depression (p<.01), asthma symptoms (p<.05) and quality of life (P<.05). Follow-up findings emphasized the efficacy of both ASMP and CBT in management of asthma and, at the same time, highlighted better outcome of CBT over ASMP.


   Discussion Top


Groups were not comparable on baseline assessment on ABP-B (p<.01). ASC (p<.05) and HADS (p<.01). It was observed that this difference was because of the dropouts in study. Difference disappeared when comparison was carried ut including dropts. Patients in both groups reported high distress. Patients with asthma have been reported to show higher levels of anxiety and depression as compared to normal controls and other illness patients [2],[3],[4],[5],[6],[7],[8],[9],[10],[1],[12],[13],[14],[15],[16],[17],[18],[19] .

Kotses et al [6] reported improvement in asthma symptoms following a group self-management program similar to present study. They emphasized on use of cues from asthma diary as a signal to initiate self-management behavior to control asthma. In present study, although, the same was not emphasized, it was observed that patients by themselves used information from asthma diary to initiate self-management behavior to control asthma. Present study patients seem to prove the observation made by Kazdin [20] that self-monitoring of behavior might actually produce a change in behavior in a desired direction.

In present study, improvement was more prominent following CBT than that of Snyder et al 4 group self­-management study. It could be because of the content of CBT and the fact that patients in present study (Snyder et al conducted two marathon sessions of 2½ hours each) got more opportunities (13-15 sessions) to review their self-management behavior, which led to better control of asthma.

Maes and Schlosser [8] , comparing CBT with a control group, and Colland [23] , comparing CBT with a self management program with children reported findings similar to present study. However, asthma symptoms were not measured in Colland's study. Present study extended findings of Colland's study by showing that CBT was effective in reducing asthma symptoms. Further, present study extended efficacy of CBT in adult asthma patients.

Present study findings were different than Sommuruga et al [9] no difference in decrease in distress in CBT group compared to a control group. Their study involved in-patients in a rehabilitation set-up. They, however, attributed improvement in both groups to rehabilitation approach per se, not to CBT.

Improvement in QOL in present study was larger than reported by previous studies following self-management programs [24],[25]. These studies reported minimal to moderate change (change of .5 to <1.5) on AQLQ. One of the reasons may be that programs used in these studies were not as intensive and comprehensive as CBT used in present study. Turner et al [24] . studied effect of written action plans and Shah et al [25] . studied effect of peer led education program in groups.

There have been studies reporting efficacy of combination of CBT and standard pharmacotherapy over standard pharmacotherapy only in improving asthma symptoms, pulmonary functions [9],[10] and distress [10] , and self management programs reporting improvement in asthma knowledge, asthma control [21] , depression [6] , and bother [22] . Present study adds more to that and reports efficacy of CBT over self-management program.

As stressed by International consensus guidelines for asthma management [14],[15] asthma education and self management were common elements in both groups. However, to achieve an improvement in asthma related symptoms, a change in self-management behavior is required, specifically, improved knowledge has to be translated into a change in behavior. In present study, homework assignments to practice self-management behavior at home and review of these skills in sessions ensured change in self-management behavior of patients, thus, leading to significant improvement in both groups.

Better outcome in CBT group in present study can be understood by Padesky and Mooney's [26] simple bidirectional understanding of psychological processes underlying any human behavior. They highlighted four inter-related aspects (cognitive, behavioral, affective and physiological), core aspect of CBT, of human behavior and asserted that change in any one of these aspects affects all of the others. So, managing anxiety and distress lead to cheerfulness which lead to positive outlook which lead to constructive behavior such as increased compliance which lead to better management of illness and which in turn lead to decreased anxiety and distress and so on.

Follow-up findings showed that CBT group patients were able to apply self-management skills more effectively, able to handle their negative emotions and were able to experience a better QOL than SM group patients, after completion of therapy.

Present study had limitations. Follow-up could not be done for all patients, it was possible only for some patients, which restricts findings of study. Information on lung funcitns such as FEV1 could have given more information. FEV1 was planned initially but was dropped later because of time and financial constraints.

In conclusion, present study findings prove the efficacy of cognitive behavioral intervention in management of asthma. It is to be seen whether this gain in improvement over self-management program is cost-effective or not.

 
   References Top

1.Creer TL, Ipacs J, Creer PP. Changing behavioral and social va-i bles at a residential treatment facility for childhood asthma.J Asthma 1983; 20:11-15.  Back to cited text no. 1    
2.Lyketsos GC, Karabetsos A, Jordanoglou J, Liokis T, Armagianidis A, Lyketsos CG. Personality characteristics and dysthymic states in bronchial asthma. Psychotherapy and Psychosomatics 1984;41:177-85.  Back to cited text no. 2    
3.Juniper EF, Guyatt GH, Ferrie PJ, Epstein RS. Evaluation of impairment of health-related quality of life in asthma:developmetn of a questionnaire for use in clinical trials. Thorax 1992;47:76-83.  Back to cited text no. 3    
4.Snyder SE, Winder JA, Creer TJ. Development and evaluation of an adult asthma self-management program: Wheezers Anonymous.J Asthma 1987; 24:153-158.  Back to cited text no. 4    
5.Creer TL, Kotses H, Reynolds RVC. Living with asthma: Part II. Beyond CARIH. J Asthma 1989; - 26:31-51.  Back to cited text no. 5    
6.Kotses H, Bernstein IL, Bernstein DI, Reynolds RV, Korbee L, Wigal JK, et al. A self-management program for adult asthma. Part I : Development and evaluatioin . J All Cli Imm 1995; 95: , 529-540.  Back to cited text no. 6    
7.Wright RJ, Rodriguez S, Cohen M. Review of psychosocial stress and asthma : an integrated biopsychosocial approach. Thorax 1998;53: ' 1066-1074.  Back to cited text no. 7    
8.Maes S, Scholesser M. Changing health behaviour outcomes in asthmatic patients: a pilot intervention study. Soc Sci Med 1988;26:359-64.  Back to cited text no. 8    
9.Sommaruga CD, Spanevello A, Migliori GB, Neri M, Callegari S, Majani G. The effects of cognitive behavioural intervention in asthmatic pz-atients. Monaldi Arch Chest Dis 1995; 50: 398-402.  Back to cited text no. 9    
10.Grover N, Kumaraiah V, Prasadrao PSDV, D'Souza G. Cognitive behavioural intervention in bronchial asthma. J Asso Physi India 2002; 50:896-900.  Back to cited text no. 10    
11.American Thoracic Society. Standards for the diagnosis and care of patients with chronic obstructive pulmonary disease (COPD) and asthma. Am Rev Res Dis 1987; 136.225-244.  Back to cited text no. 11    
12.Hyland ME, Ley A, Fisher DW, Woodward V. Measurement of psychological distress in asthma and asthma management programmes. Bri J Clin Psy 1995; 34: 601-611.  Back to cited text no. 12    
13.Zigmond AS, Snaith RP. The Hospital Anxiety and Depression Scale. Acta Psych Scan 1983; 67:361.  Back to cited text no. 13    
14.Global initiative for asthma. A practical guide for public health officials and health care professionals. (National Institutes of Health Publication No. 96-3659A). Bethesda MD: NIH 1995.  Back to cited text no. 14    
15.National Heart, Lung and Blood Institute. Guidelines for the diagnosis and management of asthma. (NIH Publication No. 97­ 4051A). Bethesada : NIH 1997.  Back to cited text no. 15    
16.Nagarathana R, Nagendra HR. A new light for asthmatics. Bangalore: VK Yoga Prakashna 1998.  Back to cited text no. 16    
17.Meichenbaum DH, Deffenbacher JL. Stress inoculation training. Counse'ing Psychol 1988; 16:69-90.  Back to cited text no. 17    
18.Juniper EF, Guyatt GH, Willan A, Griffith LE. Determining a minimal important change in a disease specific quality of life questionnaire. J Cli Epi 1994; 47: 81-87.  Back to cited text no. 18    
19.Centanni S, Di Marco F, Castagna F, Boveri B, Casanova F, Piazzini A. Psychological issues in the treatment of asthmatic patients. Respir Med 2000; 94: 742-749.  Back to cited text no. 19    
20.Kazdin AE. Self-monitoring and behavioural change. In MJ Mahoney & CE Thoresen (Eds.), Self-control: Power to the person. Monetay, CA: Brooks/cole 1974.  Back to cited text no. 20    
21.Kotses H, Stout C, McConnaughy K, Winder JA, Creer TL. Evaluation of individualized asthma self-management programs. J Asthma 1996; 33:113-118.  Back to cited text no. 21    
22.Wilson SR, Scamagas P, German DF, Hughes GW, Lulla S, Coss S,et al. A controlled trial of two forms of self-management education for adults with asthma. Am J Med 1993; 94:564-576.  Back to cited text no. 22    
23.Colland VT. Learing to cope with asthma: A behavioural self­ management program for children. Patient Edu Coun 1993; 22: 141-152.  Back to cited text no. 23    
24.Turner MO, Taylor D, Bennett R, Fitzgerald JM. A randomized trial comparing peak expiratory flow and symptom self-management plans for patients with asthma attending a primary care clinic. Am J Respir Crit Care Med 1998;157: 540-546.  Back to cited text no. 24    
25.Shah S, Peat JK, Mazurski EJ, Wang H, Sindhusake D, Bruce C, et al. Effect of peer led programme for asthma education in adolescents: Cluster randomised controlled trial. Bri Med J 2001; 322.583.  Back to cited text no. 25    
26.Padesky CA, Mooney KA. Presenting the cognitive model to clients. Int Cog Ther Newsletter 1990; 61:13-14.  Back to cited text no. 26    


    Figures

  [Figure 1]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]


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