Original Article

Avoidance of Allergens by The Patients with Bronchial Asthma

D Behera*, Sukhpal Kaur**, D Gupta*, SK Verma***

*Department of Pulmonary Medicine; **National Institute of Nursing Education; ***Department of Psychiatry, Postgraduate Institute of Medical Education and Research; Chandigarh, India.
Received : 24.4.2007; Revised : 19.3.2008; Accepted : 3.4.2008

Abstract

Objectives: Association between environmental allergens and bronchial asthma is well established. A great number of substances found in the environment can precipitate or aggravate respiratory symptoms in asthmatics. Avoiding allergens is recognized as an integral part of management. Through various educational interventions the patients can be taught various measures to avoid these allergens. The present study was undertaken to evaluate the impact of ‘self care manual’ an educational intervention on the avoidance of various environmental allergens.
Methods: The total enrolled patients were 523 of which 260 were included in the study group to whom ‘self care manual’ was given and 263 in the control group with no access to self care manual. A fourteen items interview schedule consisting of three parts was administered. The first two subparts were in the form of checklist to know the various allergens which were inducing symptoms in the patients and weather they could avoid these triggers. The third part which was open ended was administered to know their ways of avoiding these triggers. All the patients were followed up at 2 weeks, 6 months and at 1 year.
Result: Mean age of the subjects in both the groups was 36.72 ±11.52 years and 34.33± 12.86 years respectively. Both the groups were comparable on majority of the socio-demographic variables. The number of patients whose symptoms were aggravated by a particular triggering factor reduced significantly on each successive visit in the study group. Almost all the patients started avoiding their triggers in follow-ups in the study group. In control group this change was only for few triggers. More and more patients started using inhalers on exposure to dust or triggering weather conditions. They started slowing down for exercises and diverted their attentions against triggering emotional situations.
Conclusion: Patient education should be an essential component in the overall management of bronchial asthma. Control of asthma symptoms is better achieved with avoidance of allergens. This can be accomplished by emphasizing these facts particularly with the use of self care manuals. ©

Introduction

Despite advances in therapeutic modalities, prevalence of asthma and other allergic diseases have increased recently. The reasons for these trends are complex. Association between environmental allergens and asthma is well established. Both indoor and outdoor allergens can trigger asthma but the indoor allergens can be particularly problematic as population in most of the developed countries have moved indoor and their homes have become more airtight with less ventilation creating ideal conditions for the house dust mite to multiply. Severity of asthma is related to allergen exposure. In the French Alps, where exposure to house dust mite allergens is low, people have a lower prevalence of allergy to mites and asthma than those at sea level where exposure to house dust mite is high.1 The various indoor allergens studied are cockroaches, house dust mites, molds, cat, dog and mouse allergens.2-8
Allergen avoidance is recognized as an integral part of the overall management of asthmatic patients and is one of the four primary goals of good asthma management recommended in all asthma guidelines.9 Asthmatic patients may be sensitized to number of allergens, asthma morbidity can be reduced when exposure to even a single indoor allergen is reduced. In one of the studies avoidance of house dust mite by applying liquid nitrogen to mattresses and bed room carpets was studied. There was a significant reduction in the live mites, improvement in the symptom score and also in the Peak Expiratory Flow Rate in the avoidance group than the control group.10 However to improve adherence to allergen avoidance the patients need to be provided with concentrated education on various measures. Without formal education programme patients do not use mattress covers and with the usual clinic based educational efforts 17% installed mattress cover.11 The present study was undertaken to evaluate the impact of an educational intervention on the avoidance of various environmental allergens that trigger the symptoms in patients with bronchial asthma and also to identify the measures taken by them to avoid these triggering factors.

Material and methods

The study was conducted in the outpatient clinics of the department of Pulmonary Medicine, Post Graduate Institute of Medical Education and Research Chandigarh. A total of 523 patients were included in the study. Using a Random Number table the selected patients were allocated to two groups-(i) study group (260 patients) to whom educational intervention in the form of a ‘self care manual’ was provided and (ii) control group (263 patients) with no access to the ‘self care manual’. Self-care manual contained detailed information regarding various types of indoor and outdoor allergens and the preventive measures they should take to avoid these triggers. An interview schedule (14 items) comprising of three parts was used. These items were cigarette smoke, smoking, dust, hot/humid weather, pollens, cold weather, fungus/molds, domestic cooking, and change of weather, drugs, emotions, exercise, odours and smoke. The first part was whether the symptoms of the subjects were induced and/or aggravated by exposure to various triggers. The second part was that if they could avoid these triggers, and how they could avoid these triggers i.e. the ways of avoiding, were included in subpart three. The first two parts were in the form of checklist and the third part was open ended as the subjects were asked regarding their ways of avoiding these triggers. All the study group patients were asked to report for the follow up at 2 weeks, 6 months and at one year. The detailed methodology has already been published.12-13 Data was analyzed using descriptive and inferential statistics.

Results

Follow up: In both the groups (study and control), 240(92.31%) and 240(91.25%), 212(81.54%) and 210(79.85%), 204(78.46%) and 194(73.76%) patients, completed the 2 week, 6 month and 1 year follow up respectively.
Demographics: The mean age of the subjects in both the groups was 36.72 ±11.52 years and 34.33± 12.86 years respectively. As per the duration of the illness 74(36.27%) from the study group and 73(37.63%) from the control group had asthma for the last 1-5 years. The two groups were comparable on majority of the socio-demographic variables.
Triggers of bronchial asthma: The number of patients whose symptoms were aggravated / triggered by a particular triggering factor reduced significantly on each successive visit. In study group this trend was similar for all the triggers. However in control group, a significant reduction in the number of patients occurred from first to subsequent visits for cigarette smoke, hot and humid weather, pollens and cold weather, while there was no significant difference for other triggers.13
Details of triggers: Table 1 shows the types of odours, medications, emotions, and physical activities that used to precipitate / aggravate the symptoms in bronchial asthma patients. About half of the patients in both the groups had problem with all the type of odour. However, strong odour was precipitating symptoms in majority of the patients in both the groups. About one fourth of the patients were having their symptoms started when they were excessively laughing or due to sadness. About half of the patients were having their symptoms initiated when they were having some mental tension. In more than 50% of the patients brisk walking was predominantly precipitating symptoms among all the types of physical exertion.
Ways of avoiding triggers: Significantly more (almost 100%) patients started avoiding their triggers in follow up as compared to first visit in study group, whereas this change was significant only for three triggers (hot and humid weather, pollens and change of weather) in control group. In the study group the number of patients who started avoiding cigarette smoke increased from 90.73% at first visit to 94% at 2 weeks follow up to 100% each at 6 months and 1 year follow up (χ2=16.53, p<0.001). The corresponding figures for control groups were 95.6%, 96.6%, 94.7% and 98.4% (χ2=2.54, NS). A similar change occurred in study group for avoiding dust with percentage of affected patients who started avoiding exposure to dust increases from 84% to 86.86%, 87.43% and 92.49% (χ2=34.57%. p<0.001) with an insignificant change in control group from 84% at first visit to 86.86%, 87.43% and 9.49% (χ2=6.01,NS) respectively on the three follow up visits. Similar successive improvement in percentages of affected patients in study group were observed regarding avoiding hot and humid weather, pollens, cold weather, change of weather, fungi/molds, emotions, exercise, odour and smoke. More and more patients had started using inhalers on exposure to dust and triggering weather conditions. They also started slowing down for exercise and diverted their attention against triggering emotional situations. There was no change in the ways of avoiding the triggers against two triggers (cooking fumes and fungi) in study group and four triggers (fungi, emotions, odour and smoke) in control group.

Discussion

As there is a lot of misconception and a good amount of misinformation in general public regarding causes of bronchial asthma, they keep on avoiding dietary and other items which in fact have no role to play in either the causation or management of bronchial asthma. Rather this must be offering a lot of confusion, agony and frustration to these ignorant and misinformed patients. An understanding of disease in bronchial asthma as in any other chronic disease goes a long way to ameliorate their sufferings. Giving written information helped the patients to identify their triggers and they started avoiding them with successful outcome. The inference goes that without proper knowledge of the disease simple drug treatment in asthma remains an inadequate approach. Providing right information not only empower them to understand their disease in an appropriate way, but in fact it also helps in the optimum utilization of drug management. In the current study the knowledge scores were significantly higher at all the three follow up visits as compared to baseline in the study group patients. In both the groups the symptom score decreased at all the follow up visits.13 It was observed that the number of patients whose symptoms were aggravated/triggered by a particular triggering factor reduced serially on each successive visit. This trend was similar in case of every trigger in study group and this reduction in the number of subjects was statistically significant for each trigger (except medicine, where the number remained the same as every body was avoiding incriminating medicines). More and more subjects during follow up adopted the strategies to avoid the contact with the triggers. But such significant reduction was more in the study subjects as compared to control subjects. Huss et al14 gave verbal/written and computer assisted guidance to asthma patients allergic to dust mite. The instructions were regarding avoidance measures in house dust allergy. Their intervention resulted in better environmental control measures like encasing mattresses and pillows, removing carpeting and upholstered furniture, laundering bedding in hot water and controlling indoor temperature and humidity. There was a significant decline in mattress mite allergens. Mean symptom score decreased by 26% and there was a lesser use of medication. In a meta-analysis15 done on control measures in the management of asthma, it was concluded that the total number of patients who improved after intervention (41/113) was similar to the control group patients (38/117). In the current study one subject from the study group having pets had given his dog away to his friend. The similar findings have been depicted by Oliveira et al16 that before the intervention 48.3% of the patients avoided triggers and carried out environmental control, this percentage increased to 74.1% after the program. Similarly Ringsberg et al17 found that in the intervention group, all the patients knew that smoking and certain flowers could cause deterioration of their asthma. Before attending the asthma school 5/20 patients in the intervention group knew that certain drugs should be avoided and after attending 13/20 had the knowledge. In the same study in the intervention group 4/20 gave their pets after attending the asthma school and in the control group one person bought a new pet. Exposure to the programme increased the belief that preventive action should be taken before doing the exercises. In the current study, significant improvement in control group for a few trigger was probably affected by their sensitization due to administration of same questionnaire as it might have given them an idea to identify and thus avoid culprit triggers.
As the cost of asthma management is increasing day by day, the best approach to the treatment of asthma should be an integrated approach in which the usual treatment should be accompanied by environmental control of the allergens to which the patient is sensitized.

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