The burden of asthma in children: a European perspective

Transcription

1 PAEDIATRIC RESPIRATORY REVIEWS (2005) 6, 2 7 MINI-SYMPOSIUM: THE BURDEN OF ASTHMA The burden of asthma in children: a European perspective Felix H. Sennhauser 1, *, Charlotte Braun-Fahrländer 2 and Johannes H. Wildhaber 3 1 Department of Paediatrics, University Children s Hospital, CH-8032 Zürich, Switzerland; 2 Department of Social and Preventive Medicine, University of Basel, CH-4051 Basel, Switzerland; 3 Division of Respiratory Medicine, Department of Paediatrics, University Children s Hospital, CH-8032 Zürich, Switzerland KEYWORDS asthma prevalence; asthma control; burden of asthma; quality of life; healthcare costs Summary Asthma is the most common chronic disease in childhood, imposing a huge burden on the patient, their family and society. It is a worldwide disease with variable expression between countries and between different populations in a country. There is evidence that its prevalence has increased considerably over the last two decades and is still increasing, despite there being some indications that the increase in prevalence may have plateaued in some countries in the last few years. Better understanding of the natural course of asthma and improved asthma control can lead to a decreased burden on the patient, their family and society. The burden of asthma consists mainly of a decreased quality of life for the patient and their family, as well as high costs for society; the healthcare expenditures for asthma in developed countries are 1 2% of the total healthcare costs. ß 2005 Elsevier Ltd. All rights reserved. INTRODUCTION Depending on disease characteristics, such as prevalence, natural course and disease control, the burden of a disease can have a major impact on the patient, their family and society. Bronchial asthma is a major cause of morbidity in children in developed countries. Over recent decades, a large number of epidemiological studies investigating the prevalence of childhood asthma have documented an increase in prevalence. 1 Asthma affects about 8.6 million children in the USA. 2 In Westernised countries, it is estimated that 5 10% of children have asthma, making this * Corresponding author. Tel.: /03; fax: address: felsen@kispi.unizh.ch (F.H. Sennhauser). respiratory disorder the most common chronic disease in the paediatric population. Asthma is a chronic, complex, obstructive lung disease characterised by acute symptomatic episodes of varying bronchial constriction that occur in response to viral infections or other triggers such as allergens and exercise. 3 Paediatric asthma accounts for a large proportion of childhood hospitalisations, healthcare visits, absenteeism from day care/school and missed work days by parents. 4 Multiple factors are responsible for excessive asthma morbidity including undertreatment, lack of adherence to recommended treatment regimens, inadequate antiinflammatory medication, environmental triggers, inadequate patient/family/caretaker education and overdiagnosis (especially in the very young child). The purpose of this article is to determine the burden of childhood asthma and to define possible factors with an /$ see front matter ß 2005 Elsevier Ltd. All rights reserved. doi: /j.prrv

2 BURDEN OF ASTHMA IN CHILDREN: A EUROPEAN PERSPECTIVE 3 impact on the patient, their family and society in Europe or the USA. This report reviews the literature on asthma imposing a growing burden in terms of morbidity, quality of life and healthcare costs. BURDEN OF ASTHMA DIFFICULT TO DEFINE It is impossible to develop a single estimate for the burden of asthma. 5 Several surrogate single parameters have been used in order to quantify the burden of asthma, such as data on prevalence, severity, lung function, general practitioner and hospital attendances, treatment regimens, morbidity and mortality, quality of life, limitations in normal life, direct/ indirect costs and a few other asthma-related measures. However, these parameters only address the burden in regard to some limited aspects of the patient, their family or society. In addition, all these surrogate parameters lack a clear definition and overall acceptance for internationally comparable surveys because of the following methodological deficits. Methodological deficits affecting prevalence estimates There is no agreed definition of childhood asthma, which differs in different age groups. There are limitations to the use of questionnaires in the epidemiological measurement of childhood asthma. Objective measures of lung function only depict children with airway obstruction. This may be absent even with ongoing bronchial inflammation. Methodological deficits affecting severity estimates The measurement of asthma severity is difficult and depends on the perception of asthma by children and/or parents and on the perspective of the professional observer. Even in children with persistent asthma, the percentage with severe airway hyper-responsiveness is sometimes less than 1%. Methodological deficits affecting lung function estimates Peak expiratory flow (PEF) and forced expiratory volume in 1 s (FEV 1 ) measurements may not be a feasible assessment tool as more than 80% of children with asthma have normal PEF and FEV 1 levels. Airway hyper-responsiveness and symptoms (wheeze, chest tightness and cough) measure different abnormalities in the airways. Methodological deficits affecting care attendances and morbidity estimates It is difficult to ascertain how many paediatrician, general practitioner and hospital attendances are indicative of poorly controlled asthma. Variations in diagnostic habits have a large influence. Methodological deficits affecting quality of life and limitations in daily life estimates How quality of life or limitations in daily life are affected depends mainly on the patient s expectations, which may be greatly influenced by the cultural background. Only a limited number of validated quality-of-life questionnaires are available. Methodological deficits affecting asthmarelated cost estimates The existence of different points of view regarding costs, from the patient, the healthcare professional and organisations that provide health care. Different variables affecting costs between developed and developing countries. The precise relationship between socio-economic factors and asthma varies between countries. Different healthcare systems. Therefore, to account for methodological deficits, it seems more reasonable to define a number of parameters for the assessment of the overall burden of asthma and/or the specific burden on the patient, their family or society than to use a single surrogate parameter. To date, the overall burden of asthma can best be defined as the aggregate data from prevalence, lung function measurement, ambulatory consultations, hospital admissions, poor treatment and management, quality-of-life parameters, mortality figures and estimates of healthcare costs. PARAMETERS IN THE ASSESSMENT OF THE BURDEN ON THE PATIENT Derived from recently published surveys on disease burden, a number of different parameters may be used to assess the impact of asthma on those who have it, as follows: number of asthma-symptom days; number of night-time awakenings; number of asthma attacks; number of emergency department visits/urgent physician visits; number of hospitalisations; use of quick-relief medicines/rescue medication;

3 4 F. H. SENNHAUSER ET AL. number of oral prednisone courses; number of prescriptions; number of missed days from school; effect on quality of life; effect on lifestyle, activity and exercise; consequences on professional career; direct expenditures for medical care and medical costs; indirect costs arising from morbidity and mortality; side-effects of asthma medications (such as growth rate, candidiasis and oesophageal reflux); and epidemiological means of asthma such as prevalence rates and mortality figures. This list nicely reflects the urgent need for an overall accepted definition for the burden of asthma on the patient. This may differ with race, income, society, healthcare system and other influences. PARAMETERS IN THE ASSESSMENT OF THE BURDEN ON THE FAMILY Missed work of adult caretakers due to the child s asthma. Effect on quality of life of siblings, parents and caretakers. Effect on lifestyle and activity of siblings, parents and caretakers. Consequences on professional career of parents and/or caretakers. Direct expenditures for medical care and medical costs. Indirect costs arising from morbidity and mortality including the value of time lost from work by parents/ caretakers. times and the anticipated benefit are other aspects of costs and will influence the decision to visit a doctor. These influences might become even more important in countries with difficult employment status because of impending fear of losing the job or loss of income. Bronchial asthma adversely impacts on patients healthrelated quality of life. The genetic components in question are symptoms, physiological functions, psychological states, perceptions of current health (as a state of complete physical, mental, psycho-emotional and social well-being not merely the absence of disease), expectations of future health, satisfaction as a whole, pleasure, school/work productivity, social functioning, cultural and spiritual fulfilment, economic well-being, capacity to cope with adversity and many others (Fig. 1). 7 It has to be stressed that quality of life depends greatly on individual expectations as well as specific factors, especially regarding coping strategies (Fig. 2). Again, this list nicely reflects the urgent need for an overall accepted definition for the burden of asthma on the family. This may also differ with race, income, society, healthcare system and other influences. The burden on the patient and the family Bronchial asthma as a chronic disease is best cared for by practitioners and clinicians in an environment of therapeutic partnership with patients and families. Thus, knowledge of the nature and impact of the burden of asthma in children s lives is of crucial importance for the understanding of possible impediments to treatment and care. Derived from publications of this sort of qualitative research, there are some possible obstacles for a successful partnership between patients, parents and their doctors. 6 The cost of therapy is a general concern for the majority of patients. The capacity to afford medication is a determining factor of treatment choices. Socio-economic aspects, therefore, will influence the ways of managing financial costs, such as not buying the medication or lowering/altering the dosage in order to prolong medication use. For parents and caretakers, the necessity to take time off work, travel, waiting Figure 1 (a) The network of different interdependent aspects defining quality of life in children: crucial role of the (psychosocial) environment. (b) Despite stable physiological disease functions, the age-related (normal!) changes of external demands might destabilise quality of life, with the risk of secondary deterioration of functional parameters, especially during adolescence.

4 BURDEN OF ASTHMA IN CHILDREN: A EUROPEAN PERSPECTIVE 5 attack often influences decisions about holiday destinations, sporting activities, playing at school or with animals, socialising with friends and participating in school camps. An emotional burden, especially during adolescence, arises from the role change from wanting to be independent of help when being well to needing support from family and friends during an attack. This caring role by family members and friends might result in their absence from school, work or social activities, leading to even greater consequences and stress for them than for the asthmatics themselves. Thus, psychosocial aspects in general have an integral role in the morbidity of asthma-related quality of life an important impact on daily life of the patient, siblings and parents. Figure 2 The level of quality of life greatly depends on individual expectations as well as individual specific factors, especially regarding coping strategies. The more comprehensive understanding is of the impact of asthma on daily life, the more deficient is our knowledge of the overall burden of asthma. Various instruments are available for research in asthma-related quality of life. They all measure multiple surrogates to infer quality of life and validate the correlations between low quality-of-life scores and increased utilisation of medical services for asthma and worse outcomes in asthma. Research also documents the impact of interventions to improve the control of asthma, resulting in improved quality of life measured by symptom scores and overall costs of asthma. Available reviews of interactions between subjective measures, such as symptom scores, and objective parameters, such as physiologial lung function measurements, showed poor correlation (Fig. 3). Living with asthma has a substantial impact upon child and adult lifestyles. Both groups feel tired and frustrated by their emotions of fear and panic associated with recurrent experiences of asthma attacks. 8 The potential impact of an asthma PARAMETERS IN THE ASSESSMENT OF THE BURDEN ON SOCIETY Healthcare costs arising from asthma may be the major burden on society. Socio-economic factors are integral to asthma care. However, they do not only affect society but also the patient and their family. There are other important factors, such as the patient s absence or his or her physical or psychological limitations, which not only have a major impact on the patient and/or their family but also on group dynamics in school activities and in extracurricular activities and hence on society. Therefore, there is some overlap of parameters in the assessment of the burden on society with those parameters in the assessment of the burden on the patient and/or their family. Costs (direct and indirect expenditures). Absence from school as an impairment of long-term educational achievement. Loss of learning time. Disruption of class work. Consequences on professional career of family members. Impaired socialising opportunities. Missed recreation opportunities. Figure 3 The magnitude of changes in physiological parameters, such as lung function measures, may not reflect the magnitude in change in quality of life. The cost burden on society The economic appraisal of asthma care and therefore the cost of therapy have grown over the last few years, probably in response to healthcare-cost-containment policies. 9 Asthma-related costs include direct expenditures for medical care (hospitalisation, outpatient services, physician services and office visits) and medical costs (medication for asthma and asthma-related problems such as gastro-oesophageal reflux, oral candidiasis etc.). Indirect costs mainly include opportunity costs and arise from morbidity and mortality. Indirect costs also include the economical value of time off work by parents and caretakers of children suffering from asthma and the loss of school days. The importance of economic outcomes will continue to grow to determine whether an effective

5 6 F. H. SENNHAUSER ET AL. asthma treatment is also cost-effective and to allow health organisations to ensure appropriate use of resources. As patient satisfaction increases in importance as an outcome measure the indirect costs will gain impact with policy makers. Indirect costs are an indicator of asthma impact on individuals and families, reflecting their functioning and quality of life in the presence of the disease. 10 HOW TO REDUCE THE BURDEN OF ASTHMA It could be expected that by understanding and reducing the factors contributing to the burden of asthma, the overall burden, as well as the specific burden on the patient, their family and society, could be greatly reduced. The prevalence of asthma varies worldwide, most likely due to different genetic backgrounds as well as different exposure to various risk factors such as respiratory infections, indoor/outdoor pollution and diet. Understanding the interaction of risk factors and genetic predisposition would help in the introduction of preventive strategies and hence reduce the prevalence of the disease. Longitudinal studies aid our understanding of the natural course of asthma in well-defined populations. These studies may not only clarify the implications of long term primary, secondary and tertiary preventive strategies by also help to define more effective preventive strategies. It is generally believed that the level of disease control correlates with the overall asthma burden as well as the specific burden for the patient, their family and society. However, asthma control, as defined by national and international therapy guidelines, is not achieved in a significant number of asthmatic children. 11 This finding applies particularly to children younger than 5 years of age. In schoolaged children, highly effective medication is available but is often not taken. Patient goals of asthma control may not match the goals stated in guidelines. Reasons for this noncompliance may be various. It could be expected that the burden of asthma can be greatly reduced if overall asthma control is improved. However, it has to be cautioned that the correlation between interventional measures and benefit is not linear and has to be well balanced (Fig. 4). It has been shown that an interactive multimedia programme for asthma control and tracking can significantly improve asthma knowledge of children and caregivers, leading to fewer asthma-symptom days and a decreased number of emergency department visits. 12 Asthma education might become a major factor in reducing the burden of childhood asthma. To date, several health system barriers exist (allocation of adequate staff time, selection of instructional approaches, age-related adjustment of educational content, lack of reimbursement for patient education) that make it difficult to offer effective education programmes, especially in medical settings. Therefore, if costs for asthma care are to be further reduced, emphasis of future research and strategies should Figure 4 The amount of effort put into interventional measures does not correlate with the benefit. As such, this has to be well balanced. focus on improving the effectiveness and efficiency of primary care in the ambulatory setting. Research on factors related to the burden of asthma will certainly widen our strategy to reduce the impact and consequences of asthma on patients and families lives. Based on available evidence in published surveys, several elements can already be recommended, differing for patients, doctors and researchers: 8 eliminate exposure to tobacco smoke in the individual s home and in public; supplement traditional verbal and printed asthma education with interactive multimedia programmes; improve management strategies for patients and families by increasing their knowledge and awareness of asthma medication, asthma control, removal of barriers to adherence and treatment recommendations; increase the access to and the use of school-based health centres and ambulatory health care that is of high quality and improved continuity; adapt financial reimbursement concepts and co-payments to individual socio-economic status in order to improve medication adherence; ascertain the patient s perspective of the affordability and acceptability of medication to achieve optimal treatment compliance; explore the patient s individual ( real ) burden of asthma to form a therapeutic partnership with patient, family and caretakers; define the goal of treatment and asthma care in concordance with the patient; find efficient and effective ways to diagnose and treat children suffering from asthma; and decide on meaningful definitions of asthma, for individual care and population surveys, in order to better compare prevalence rates, severity and health outcomes with time, intervention and prevention. To date, there is no cure for asthma but the disease can be treated and controlled by good management, thus improving quality of life and lowering mortality and hospital

6 BURDEN OF ASTHMA IN CHILDREN: A EUROPEAN PERSPECTIVE 7 admissions. To further reduce the overall burden of asthma, more evidence is urgently needed for answering the following (research) questions. What responsibility for reducing the burden of childhood asthma should be borne by the patient, family, caretakers, doctors, clinicians, paramedicals, asthma associations, government and insurance companies? What is the role for protective factors in preventing the development of asthma and therefore in reducing its prevalence? What is the possible benefit of screening programmes for early intervention strategies? What is the ultimate goal and optimal outcome measure for adequate cost benefit assessment of prevention and intervention strategies? CONCLUSION Childhood asthma exerts a tremendous burden on patients, families, caretakers, society and healthcare providers. Recognising the sizeable disease burden should establish asthma as a priority area in national healthcare strategy. A better understanding of aetiology, pathogenesis, risk factors and protective influences for asthma development may improve primary, secondary and tertiary preventive measures. Improved individual targeting of existing therapies and facilitating the development of newly designed treatment options will contribute to reducing the disease burden. A holistic approach to optimal asthma care should not only include medical parameters but must integrate outcome measures of health-related well-being and quality of life and its impact on society and healthcare costs. REFERENCES 1. Global Strategy for Asthma Management and Prevention. Prevalence of Asthma. Bethesda, MD: National Heart, Lung and Blood Institute, NIH, 2002; pp American Lung Association. Prevalence Based and Revised National Health Interview Survey. Data and Statistics. November Available at: 3. Global Strategy for Asthma Management and Prevention. Natural History of Asthma. Bethesda, MD: National Heart, Lung and Blood Institute, NIH, 2002; pp Global Strategy for Asthma Management and Prevention. Mortality and Morbidity. Bethesda, MD: National Heart, Lung and Blood Institute, NIH, 2002; pp Global Strategy for Asthma Management and Prevention. Burden of Asthma. Bethesda, MD: National Heart, Lung and Blood Institute, NIH, 2002; pp Goeman DP, Aroni RA, Stewart K et al. Patients views of the burden of asthma: a qualitative study. Med J Aust 2002; 177: Morgan M, Khan DA. Asthma: epidemiology, burden and quality of life. Adv Psychosom Med 2003; 24: Woolcock A, Bastiampillai SA, Marks GB, Keena VA. The burden of asthma in Australia. Med J Aust 2001; 175: Szucs TD, Anderhub HP, Rutishauser M. Determinants of health care costs and patterns of care of asthmatic patients in Switzerland. Schweiz Med Wochenschr 2000; 130: Gergen PJ. Understanding the economic burden of asthma. J Allergy Clin Immunol 2001; 107: S445 S Kuehni CE, Frey U. Age-related differences in perceived asthma control in childhood: guidelines and reality. Eur Respir J 2002; 20: Krishna S, Francisco BD, Balas EA, König P, Graff GR, Madsen RW. Internet-enabled interactive multimedia asthma education program: a randomized trial. Pediatrics 2003; 111: