Children with asthma have a lower health related quality of life (HRQoL) than healthy children 123 and children with severe asthma report an even lower HRQoL compared to children with mild asthma 2. Quality of life has been defined as the individuals' perception of their position in life in the context of the culture and value systems in which they live, in relation to their goals, expectations, standards and concerns 4. Naturally health related quality of life stands for the quality of life in relation to one's health. A better understanding of the different aspects of, and influences on HRQoL is necessary to be able to offer optimal psychosocial-care to children with asthma.

Stress and negative emotions of a chronic illness such as asthma often result in anxiety, depression and anger which affect HRQoL 5. At the same time, coping-style appears to be an important psychosocial moderator between stress and negative emotions on the one hand, and HRQoL on the other hand 6. Individual differences in coping with a chronic illness are described by several theories of stress and emotion 7. One of these theories is the cognitive-appraisal model of Lazarus and Folkman 8. With their theory they show that a person confronted with a stressor firstly evaluates this stressor and secondly determines his or her emotional or behavioural reaction. That is, the person evaluates whether there is potential harm or benefit (primary appraisal) and consequently decides what can be done to deal with the situation (secondary appraisal). An event is appraised as stressful when primary appraisals exceed secondary appraisals, and by using coping processes a person might be able to reduce this stress 8.

Derived from this cognitive-appraisal model an extended model for coping with a chronic disease was developed by Maes, Leventhal and de Ridder 5. Figure 1 shows this extended stress-coping model. Based on the model, other life events, disease characteristics, disease-related events, and demographic characteristics are linked to the appraisal of demands and goals. Furthermore, all factors are directly or indirectly related to coping behaviour, which itself is also moderated by external – and internal resources. Finally, all these factors together contribute to psychological, social and physical consequences (HRQoL) trough coping.

To our knowledge only a few studies investigated the extended stress-coping model in total 91011. In a sample of adult heart patients, tentative proof was found for the model in total 910. Moreover, Röder et al. 11 investigated this stress-coping model in children with asthma in a school context. In their study three different disease-related stressors were included: problems with school work, shortness of breath and rejection by peers. It appeared that all three stressors contributed to the explanation of differences found in psychosocial functioning. However, interrelations between the different factors in the prediction of HRQoL remained unclear.

The aim of our study is to further explore predictors of HRQoL with the stress-coping model resulting towards a better understanding of HRQoL of children with asthma in a general context.

The aim of the present study was to further explore predictors of HRQoL of children with asthma. This study is, to our knowledge, the first study that investigated predictors of HRQoL in children with asthma within the context of other predictors. With this study a first step is made in investigating predictors of HRQoL while taking other predictors in account. Since most studies investigate only direct relations between predictors and HRQoL it is difficult to compare results of these studies to the results found in the present study.

In the present study, tentative support was found for the notion that the stress-coping model reflects most of the relationships between the included predictors and HRQoL for children with asthma. Besides coping, no other predictors appeared to have a direct relation with HRQoL. In contrast to our results, Röder et al. 11 found more direct predictors of HRQoL besides coping. Yet, in their study concepts and variables were independently investigated and a restriction was made by investigating factors related to a school context. Several other studies also found direct predictors of HRQoL such as severity of asthma 12320. However the problem is that they also concentrated only on the direct relations between HRQoL and severity of asthma.

Several non-significant associations were found in the model. Non-significant associations imply that the parameters do not differ from zero and could be deleted from the model. However, such a decision should be based primarily on theoretical considerations 21. Since Maes et al. 5 postulated that internal and external resources have a relationship with coping, it was decided to keep the non-significant associations in the model.

In the present study, most support was found for the axis of the stress-coping model. Disease characteristics, appraisal of the disease, coping, and quality of life are all significantly related to each other. This part of the extended stress-coping model might be seen as a representation of the theory of Lazarus and Folkman 8, which indicates that this study possibly reveals some tentative support for this theory.

Furthermore, avoidance coping strategy of the child had only little influence on HRQoL. This finding seems to confirm Hesselink et al. 22 who found that an avoidance coping strategy was important for predicting quality of life for adult patients with asthma. However, by including emotional reaction as coping style in their study, the effect of avoidance disappeared as well 22. In the present study, we included both avoidance and emotional reaction as coping strategies. Possibly, the association between emotional reaction and quality of life is that strong, that it obscured the association between avoidance and quality of life.

For patients with chronic obstructive pulmonary disease (COPD) perceptions of personal control was related to better HRQoL 23. It might be possible that in the present study children with a tendency to use emotional reaction as coping strategy felt that they had less control over their disease, which might have lead to a worse HRQoL.

Finally, the finding that children with more treatment experience fewer limitations might possibly be explained by undertreatment. Both physician under-prescription of inhaled corticosteroids and the underuse by children is associated with higher hospitalisation rates and less asthma control 24. It is known that children with asthma do not use their inhaled corticosteroids as often as they should 25.

The points described above should be made with caution due to some methodological limitations. First, the questionnaires used in this study were not originally created to specifically measure the constructs of the stress-coping model. In future studies it would be desirable to put effort in developing variables specially for predicting the factors as described by Maes et al. 5. Indicating factors with more than one predictor would be desirable as well.

Secondly, some of the aspects in the model had to be left out. In regard to the small sample size, too many parameters had to be estimated when all associations of the extended stress-coping model were included 26. In future studies a larger sample size is needed to investigate all aspects of the extended stress-coping model. Despite the exclusion of some of the aspects of the model, the power to detect a model without a good fit remained small; < 0.20 27. As a consequence, the low values of the test statistics might either reflect correctness of our model or lack of sensitivity to error 21. On the other hand, the similarity of results with regression analyses gives some support to the results from the path-analysis.

Furthermore, the children recruited are from 4 different countries, so that the results might be affected by cultural or language differences. Data from the parents were received from the mothers in 69 of the 87 cases. It could be expected that answers given by fathers are different. However in this study no difference were found between answers given by the parents except for education, compared to the fathers, mothers were higher educated.

It would be worthwhile to explore whether similar results hold for children followed several years. Lanfolt et al 28 found that HRQoL significantly increased over a year. However their study focussed on children diagnosed with cancer.

The findings described in this study are specific for children with asthma, it remains uncertain how this generalises to other patient groups. For example, the finding that emotional reaction as coping strategy negatively influences HRQoL might turn out to be positive for other patient groups. The efficacy of a particular coping strategy is likely to depend on the nature of the stressful situation. Emotion-focused coping are associated with lower levels of distress in situations that are not controllable 29. Since asthma is controllable with effective management 30 emotion focussed coping might have a negative influence on HRQoL. Furthermore this study was conducted by children between seven and 12 years old. For adolescents adherence to prescribed medication and attack management is low 31. This difference in adherence between age groups might quite possible have influence on the relation between severity of the disease, treatment and the limitations that one experience.

Regarding to the coping strategy, in this study relation was found between one or two parent families and the use of emotional reaction as coping strategy. Most likely for adult patients the impact of their growing up in one or two parent families is smaller than for children living in this situation.

The results of this study gave tentative support for the notion that the stress-coping model reflects most of the relationships between the included predictors and HRQoL for children with asthma. A first step is made in identifying predictors of quality of life for children with asthma. However, future research is necessary to analyse the model and with that predictors of quality of life further. Although our results are preliminary, it seems that the factors suggested by this model are important and should be taken into account when designing optimal psychosocial-care interventions.

HRQoL Health Related Quality of Life

DISABKIDS DISABility KIDS project

CODI COping with a DIsease

KINDL the revised children quality of life questionnaire

The author(s) declare that they have no competing interests.

HMK developed the core idea and was involved with the DISABKIDS project which made it possible to use the data from this project. SB and YP conducted the literature search. YP performed the statistical analyses; all authors were involved in the interpretation of the results. YP wrote the first draft of the paper. All authors revised the first draft critically and gave final approval of the version published.