Asthma in Adolescence: Is There Any News

ASTHMA IN ADOLESCENCE: IS THERE ANY NEWS?

1 2 Diletta de Benedictis MD Andrew Bush MD

1 Department of Mother and Child Health, Azienda Ospedaliera, Perugia, Italy

2 Department of Pediatrics, Imperial College, London, UK; Department of Pediatric Respiratory

Medicine, National Heart and Lung Institute, London, UK and Department of Pediatric Respiratory

Medicine, Royal Brompton & Harefield NHS Foundation Trust, London, UK

Correspondence to: Diletta de Benedictis, MD Reparto di Neonatologia e Terapia Intensiva Neonatale, Ospedale Santa Maria della Misericordia S. Andrea delle Fratte 06156 Perugia, Italy Email: [email protected] Tel.0039-075-5786465 Fax. 0039-075-5783630

Keywords: asthma, adolescence, medication adherence, education.

AB was supported by the NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust and Imperial College London

ASTHMA IN ADOLESCENCE

1 ABSTRACT

Asthma is a chronic disease that has a significant impact on quality of life, which is particularly important in adolescence. We will discuss aspects of epidemiology, the clinical spectrum, diagnostics and management of asthma in adolescence. In particular we will highlight the psychological implications of having asthma during this developmental period. Data published in the past ten years, since we last reviewed the subject, will be the main focus of this paper.

The care of the teenager with asthma should take into account the rapid physical, emotional, cognitive and social changes that occur during normal adolescence. The diagnostic process may be more difficult since teenagers tend to deny their illness. Thus, both under-diagnosis and under- assessment of asthma severity may lead to under-treatment and potentially avoidable morbidity and even mortality. Conversely, teenagers may be misdiagnosed as having asthma or their asthma severity may be overestimated leading to inappropriate and sometimes excessive treatment.

Educational programs, environmental avoidance measures, proper use of medications along with a skilled approach and a caring attitude of health providers are all very important for successful management.

2 ABBREVIATIONS

INTRODUCTION

Asthma is a common illness in the teenage years and there is a high risk of complications1.

Under-recognition, over-treatment, erratic self-medication, along with other specific “age-linked” issues such as denial of disease severity, poor adherence with medication and risk-taking behaviors, are real threats to the wellbeing of adolescents with asthma2,3,4. Despite teenagers’ overt preference for secrecy and annoyance at adult prying, the forward-looking and healthy part of the developing adolescent psyche seeks genuine relationships with adults who can help them5. The purpose of this review is to discuss the changes in the epidemiology, assessment and management of asthma in adolescents, in order to update our previous review2.

3 PREVALENCE AND BURDEN OF THE DISEASE

Respiratory disorders are the sixth main cause of disability worldwide in people aged 10–24 years and asthma is estimated to be responsible for 346.000 deaths worldwide every year6.

The UK National Review of Asthma Deaths (NRAD https://www.rcplondon.ac.uk/projects/outputs/why-asthma-still-kills) found that 46% of deaths could have been avoided if patients had been better managed in the year before they died. In particular people did not receive key elements of routine care, prescribing errors were widespread, asthma attacks were poorly managed and people with severe asthma were not always referred to a specialist when they should have been. The overall quality of the asthma care received by those that died was judged to reflect good practice for just 4% of 19 years old or under. Several aspects of care were well below the expected standard for 46% of young people7. The findings of NRAD are extremely disappointing as potentially preventable factors were identified in over 60% of the asthma deaths studied. The Australian New South Wales Child Death Review Team annual report

(2013) revealed that there has been an increase in asthma deaths in children aged up to 17 years.

Among these, low socioeconomic status, poor follow-up care, poor adherence to medication, lack of written asthma action plans and exposure to tobacco smoke were the main risk factors8. By contrast, some countries, particularly Finland and Brazil9,10, have reduced asthma attacks and deaths to a minimum so substandard care and outcomes are not inevitable. Severe asthma management remains a major global problem, particularly in areas where recommended treatments are not available or affordable, or where it is undiagnosed or inadequately treated because of the lack of training of health care professionals11,12.

ASTHMA RISK FACTORS DURING GROWTH

The natural course of asthma is heterogeneous and dynamic13,14. Remission is common, mainly in late adolescence, with reported rates from 16% to 60%15. Mild disease before

4 adolescence, male sex, only minor airway inflammation and the absence of allergic sensitization have been associated with an increased probability of remission, but the impact of heredity, gender, smoking, and sensitization to specific allergens remains uncertain16-19. On the other hand, important risk factors for pubertal asthma include early airway obstruction, sensitization to furry animals, more severe asthma, parental rhinitis, being the firstborn child, and perinatal familial stress20-24.

Crump et al. found that extreme preterm birth (23-27 weeks' gestation) is associated with an increased risk of asthma (or at least, an airway disease) at least into young adulthood25. Moreover survivors with bronchopulmonary dysplasia (BPD) have significant impairment of respiratory function and quality of life persisting into adulthood26,27. Low birth weight was associated with asthma diagnosis in mid-childhood with symptoms persisting into adult life28.

There is good evidence that both the incidence and prevalence of asthma vary by gender and that these differences in sex prevalence change with age29. Asthma has a higher prevalence in boys before puberty and in women in adulthood, with adult females having a higher risk of having severe asthma, in addition to a greater susceptibility to the effects of smoking.

No single straightforward mechanism can explain the gender differences, but several etiologies have been proposed, including gender specific dysanaptic lung growth (a mismatch of the changes in airway size and lung size with growth), female and male hormonal influences, genetic susceptibility, immune response, and differences in consultation practices30-33.

To some extent, the differences in diagnosed asthma really reflect disparities in symptom prevalence, but Wright et al. showed that this could be compounded by the fact that health seeking behaviour also differs by gender, with girls being less likely to be taken to the doctor if they have infrequent wheeze. Further, girls who see the physician for wheeze are significantly less likely to be labelled as having asthma and to receive medication for it; moreover the lag time between diagnosis and treatment is greater for girls34.

Limited evidence also suggests that response to inhaled corticosteroid may be gender-specific, being female predisposing to decreased odds of having uncontrolled persistent asthma35; the reasons

5 for this are unclear36.

Changes in lung structure and function at key life stages such as puberty suggest a modulatory role of sex steroids in the phenomenon of asthma transitions. Indeed there is increasing recognition that sex hormones have biological and pathophysiological actions in peripheral, non-reproductive organs, including the lung37. The epidemiological data showing increased post-pubertal asthma in women suggest detrimental effects of female sex hormones. During childbearing years this appears to occur at a time when estrogen is actually at its lowest circulating concentration and progesterone is at its highest38. Moreover some women with moderate asthma observe relief of their premenstrual exacerbations taking oral contraceptives thus suppressing large fluctuations in circulating hormones; there is no simple relationship between sex steroids and asthma in women33. These data suggest complex, sometime synergistic, sometimes opposing effects of sex steroids. Considerably more work is needed to better understand the complex signalling of sex steroids and how this is affected by age, gender, type of steroids, relative local and circulating concentrations, receptor expression patterns, cell types, crosstalk and interaction between hormones, duration of exposure and disease type and status. Overall, these are important issues to consider in order to explore novel therapeutic avenues in the context of precision medicine on the basis of gender39.

Obesity has emerged as an important risk factor for asthma40-42 and it has been found to increase disease severity in asthmatic subjects and to impair disease control43-46. Although many cases of asthma are characterised by the presence of eosinophilic airway inflammation, some asthma phenotypes are pauci-inflammatory47. The relationship between obesity, which is known to be a pro-inflammatory condition in its own right, (below) and airways disease is controversial.

Adipose tissue expresses pro-inflammatory proteins such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP), that may modify both airway inflammation48 and the response to glucocorticoids49. Leptin increases with increased adiposity and has pro- inflammatory effects. In contrast, Adiponectin, which has anti-inflammatory properties, decreases with increasing adiposity50. Some obese patients diagnosed with asthma do not appear to have

6 airway inflammation51-55 However others have suggested that obesity enhances airway inflammation56-59, thus mechanisms underlying obesity-related airway disease are not well understood, and may involve at least two phenotypes, inflammatory and pauci-inflammatory60,61.

The relationship between obesity and breathlessness is also complex62. Several hypotheses have been proposed, including the effects of obesity on chest wall mechanics, the development of a pro- inflammatory state, an increased prevalence of comorbidities, such as genetic, developmental, hormonal and neurogenic influences63, changes in serum concentrations of adipokines64 and deconditioning related to lack of physical activity or lifestyle choices.

In addition, an age/phenotype dependent association was found in the Severe Asthma Research

Program; children with early onset asthma became obese, whereas there was no significant relationship between increasing body mass index and asthma duration among obese children with late onset asthma65, however this last is still debated66,67.

Studies evaluating the interaction of gender and obesity on asthma morbidity, mainly involving adults, have suggested that the deleterious effects of obesity on asthma severity are greatest in women68-71. Kattan et all. found that asthma outcome among adolescents was adversely affected by adiposity in females with worse asthma control, more asthma exacerbations, and lower FEV1/FVC, but not in males; whereas for males, but not for females, adiponectin had a protective effect independent of adiposity72. Notably, adipokines may mediate the association between obesity and asthma in a gender-specific fashion.

As well as the above intrinsic risk factors, asthma incidence and severity may also depend on the influence of extrinsic factors like environmental pollution and cigarette smoking73-75.

Despite even occasional smoking being more risky for adolescents with asthma, the smoking rate in this vulnerable population remains high76. Early passive smoke exposure, in utero or during infancy, has been recently demonstrated to influence the development of allergic disease up to adolescence77.

In patients with established asthma, tobacco smoking is associated with an accelerated decline in lung function, less responsiveness to treatment with corticosteroids and less well-controlled

7 asthma78-81.

Electronic cigarettes (e-cigs) have increased in popularity because they have been reported to contain fewer carcinogens than traditional cigarettes, cause less acute lung effects in healthy individuals and to possibly help with smoking cessation82. Polosa et all. suggested that use of e-cigs as a substitute for smoking is associated with improvements in asthma outcomes83. However, e-cigs are not harmless as they contain formaldehyde and other toxins about which very little is known.

Moreover the most significant health concerns involve the “vaping” (use of devices to breathe in substances from e-cigs as vapour rather than smoke) of cannabinoids by teenagers, as e-cigs have given young cannabis smokers a new method of inhalation84. Smoke-free legislation has led to substantial reductions in hospital attendances for asthma. Together with the health benefits in adults, this and other studies provide strong support for WHO recommendations to create smoke-free environments85. The Tucson cohort has also recently demonstrated that parental and active smoking act synergistically to increase lung function deficits in people from age 16 to 26 years86.

DIAGNOSTIC ISSUES

There are many potential pitfalls that need to be continuously kept in mind in the diagnosis and management of adolescents with asthma, particularly if the response to treatment is unexpectedly poor. There may be the tendency among teenagers to deny their illness, even when there is a previous history of asthma, leading to under-diagnosis, under-assessment and under- treatment, failure to appreciate risk and potentially avoidable morbidity.

On the other hand it is well documented that asthma severity may also be overestimated, leading to inappropriate and over-treatment of the disease87. Indeed there is often a discrepancy between the level of reported symptoms and physical findings or objective measures of asthma.

A good history is crucial, along with a complete physical examination, conducted paying specific attention to any sign that could suggest other possible diagnoses, with objective documentation of variable airflow obstruction, atopy, and ideally FeNO. Important diagnostic traps are particularly

8 likely to occur in the adolescent age group3. It is essential to consider the many conditions which may mimic asthma in adolescents with shortness of breath88.

A common symptom in adolescents is exercise-induced dyspnoea (EID). Possible causes of

EID, along with poor cardio-pulmonary fitness, are exercise induced bronchoconstriction (EIB)89,90 and exercise-induced laryngeal obstruction (EILO), where the airﬂow at the level of the larynx is obstructed during physical exertion91-93. The prevalence of EIB and EILO in a general population of adolescents was respectively 19.2% and 5.7%, with no gender differences. Almost half of the participants with EILO also had EIB, so EILO and EIB often co-exist. Approximately half of the subjects reporting EID had neither EIB nor EILO and unexplained EID was more common in boys94. A retrospective review of exercise tests in 142 adolescents presenting with EID found that only 11 (9%) of 117 (who had EID) had evidence of EIB95.

There is an increasing recognition that often adolescents with asthma restrict their physical activity for different reasons including theirs or their parent’s health beliefs, and knowledge and attitudes of teachers and sporting coaches about asthma, its management and symptom perception96,97. Physical activity has a beneficial role in the respiratory health of people with asthma. Even thought the evaluation is difficult because of heterogeneity among available studies, adolescents with low activity levels seem to have an increased risk of new-onset asthma and a higher risk of current asthma/or wheezing98. Moreover some studies in patients with EIB demonstrated that peak expiratory flow was improved substantially by training99. Due to the heterogeneity of physical training intervention type, duration, intensity, frequency, primary outcome measures, methods of assessing outcome measures, and study designs there is still no definite conclusion; however, some findings suggest physical training may reduce airway inflammation in asthmatics, with a decrease in blood levels of C-reactive protein, malondialdehyde and serum IgE , exhaled nitric oxide, and sputum cell counts. Physical activity leading to improved fitness should become part of a goal orientated management strategy by schools, families and health care professionals. Exercise induced asthma should be regarded as a marker of poor control, and asthma therapy adjusted.

9 Breathlessness due to deconditioning indicates a need to increase fitness. Neither is an excuse for inactivity. If the cause of exercise-related symptoms in an adolescent is physical deconditioning, a training program is likely to provide positive beneﬁts100,101. Lack of exercise, in addition to the risk of over-diagnosis of asthma, may have an important potential impact on the development of obesity as well as on the social interaction with peers102. Moreover EID can also have other causes such as restrictive abnormalities, primary hyperventilation, cardiac disease and congenital malformations103,104.

Chinellato et al. reported an association between EIA and vitamin D levels105. In addition it has been demonstrated that low serum levels of vitamin D correlate with increased airway remodeling and risk of exacerbation in children with severe asthma106,107, however, in the VIDA study, vitamin D supplementation failed to result in improvement in asthma control in adults108.

Longitudinal studies and interventional trials in individuals with low serum vitamin D are urgently needed to evaluate the effect of supplementation on asthma control, because cross-sectional investigations cannot determine whether vitamin D deficiency is responsible for reduced lung function in asthmatics or whether asthma associated lifestyles, such as less outdoor exercise and thus decreased exposure to sunlight or decreased dietary intake, are responsible for lower serum vitamin D levels109.

Vocal cord dysfunction (VCD), which overlaps with EILO, is also frequently misdiagnosed as asthma in adolescents. Symptoms include dyspnoea, chest tightness, cough, throat tightness, wheezing or voice change110. Social stressors are frequently identified and many adolescents are reported to over-achieve in terms of excellent academic or athletic performances111. It often mimics

EIB112, and may coexist with asthma in up to 50% of cases, thus increasing difficulties in the diagnosis113-115. VCD can be intermittently symptomatic and the characteristic flattening of the inspiratory flow volume curve is very often missing when symptoms are absent. It should be suspected on the basis of clinical symptoms in any patient in whom asthma treatment fails, especially if there are no symptoms when the patient is asleep. Confirming the diagnosis involves

10 the direct visualization of abnormal vocal cord motion while the patient is symptomatic116. Since timing of performing airway evaluation during an acute episode may be problematic, a simple clinically-centered index has been recently proposed to facilitate the diagnosis, but validation studies are needed117.

A critical issue in adolescence is psychogenic cough, which is often inappropriately treated with asthma medications118,119. Typical characteristics to consider in differential diagnosis are its absence during sleep or concentration, predominance in female sex and in patients with high achieving school performances.

PSYCHOLOGICAL ISSUES

Adolescents with chronic conditions are more likely to exhibit risky behaviors as compared to their healthy peers120. Greater depressive feelings decrease adolescents' ability to refrain from smoking and a diagnosis of asthma is also independently associated with higher levels of depressive feelings which in turn decrease functioning121. As well as the challenges of normal development, adolescents with asthma reported higher levels of social anxiety, compromised self-concept and excess suicide-related behaviour than their non-asthmatic peers122-126.

Moreover the relationship between asthma and psychological morbidity may be confounded by poor asthma control; children with well-controlled asthma had no increased risk of anxiety, depression and poor self-esteem compared with their peers127. Hence, evaluation of overall health status should incorporate quality-of-life measures such as health-related quality of life (HRQoL)128-

There are multiple reports of Beta-2-agonist inhaler misuse and abuse, by both asthmatic and nonasthmatic individuals. 27% of young people to whom an asthma inhaler had been prescribed reported having intentionally used it excessively and one-third of all adolescents had used an asthma inhaler without a prescription. Potential reasons for this misuse may be related to the perceived benefits of sympathetic stimulation. In general, inhaler misusers had signiﬁcantly higher

11 rates of cigarette, alcohol, and marijuana and other illicit drug use than inhaler non-users and users131.

MANAGEMENT GOALS

Effective transition between pediatric and adult care improves long-term outcomes. ‘Ready

Steady Go’ is a structured programs with positive benefits132. The program involves creating an individual transition plan based on generic items to which condition specific issues are added133. Both pharmacological and non-pharmacological strategies are important in adolescents’ asthma management, including allergen avoidance, patient education, regular monitoring of lung function with an asthma plan and the use of asthma control tests and asthma diaries. Promoting smoking cessation and avoidance of environmental tobacco smoke is important.

While there are a few reports of a reduced severity in EIA symptoms post-training 134,135, the majority of studies demonstrate no change in the occurrence or degree of EIA100. However, a number of these studies have reported some reductions in hospitalisations, wheeze frequency, school ab- senteeism, doctor consultations and medication usage. It is, therefore, recommended that children and adolescents with asthma should participate in regular physical activity. This may improve asthma management and associated general health benefits, whilst minimising inactivity-related health risks102. Moreover in young people with asthma swimming is proposed to be superior to other forms of exercise due to the humidified and warm air, low pollen count exposure and hydrostatic pressure on the thoracic wall136, however, some studies have raised concerns in relation to the potential pro-asthmatic effect of chlorinated pools137.

Having asthma may be perceived by the adolescent as making them different to their peers and may be denied, hidden or ignored. This can often result in non-adherence to treatment plans and predispose adolescents to poor asthma control138.Adolescents should be seen separately, so that sen- sitive issues can be discussed privately. They should be encouraged to self-manage their asthma,

12 medication regimens should be tailored to the adolescent’s lifestyle and reviews arranged regularly so that the medication regimen can be adjusted.

The basic management steps for asthma are well summarized in international guidelines4,139, while most research activity about individualized treatment is focused on severe asthma. First line preventive treatment should be with ICS. When a moderate dose of ICS fails to achieve good control of asthma, addition of a long-acting Beta2 agonist (LABA), preferably as a combination

ICS/LABA inhaler, improves clinical asthma outcomes and reduces the number of exacerbations, and achieves asthma control in more patients, more rapidly and at a lower dose of ICS than ICS given alone. Fixed combination inhalers may increase adherence and ensure that the LABA is always accompanied by ICS140. A recent pharmacological strategy to improve asthma management is the use of single maintenance and reliever therapy (SMART) with a single inhaler containing a corticosteroid (budesonide) and a LABA (formoterol) for regular maintenance treatment, but also for ad- ditional 'rescue' use on an as-needed basis141,142. This strategy provides reduction in exacerbations and improvements in asthma control at lower doses of ICS compared with conventional therapy.

Patients must be trained on how to use inhalers and their techniques need to be checked frequently.

The prescription of spacers is particularly problematic in adolescents as the devices are often con- sidered “babyish”. Hence dry powder or breath activated devices to ensure adequate drug delivery to the lower airway may be preferable143.

Short-acting Beta-2-agonists are the treatment of choice for relieving symptoms during asthma attacks. The concept of preventive medicine is often barely meaningful to this age group; teenagers are more willing to take medications when they feel ill. Because short-acting Beta-2-agonists work quickly to reduce symptoms, patients sometimes overuse them instead of using the controller medications. But overuse, misuse or abuse of quick-relief medicines may reduce their future effective-

13 ness as well as leave airway inflammation untreated and increase the risk of cardiovascular adverse effects.

Adherence to prescribed treatment in adolescents is a challenge and medication non-adherence in these patients is alarmingly high. Approximately 50% of patients on long-term therapy for asthma fail to take medications as directed at least part of the time144. Rhee et al. divide barriers to adherence in adolescents into four main types: negative perceptions regarding treatment and providers, cognitive difficulty in following medical advices, social barriers and a tendency for denial and underestimation of asthma symptoms145,146. During adolescence many factors, such as health beliefs, organizational skills and self-regulatory behavior contribute significantly to adherence. Teenagers often report fear of side effects, busy schedules and the bad taste of ICS as barriers to adherence147.

Active listening is the best basis for successful support. An empathetic approach should be used to identify beliefs and behaviors that may be barriers for optimal treatment. Techniques alone cannot successfully equip somebody for the task of having an effective relationship with another human being; a genuine acceptance of the particular state of mind of teenagers is crucial. Communi- cating with adolescents can be very demanding. Privacy should be ensured and clinic posters should relate to teenage interests. If doctors are to gain trust from these patients, they should have a holistic approach, not only tackling asthma management. It is fundamental to listen nonjudgmentally and give recommendations for medical reasons, not moral or value-based reasons. It never works to try to be ‘on their level’ or try to impress teenagers; they need their doctor not to be a peer but a worthy professional adult5.

It is increasingly important to consider the impact of social media. While social media provide new opportunities for adolescents to improve socialization skills, creativity, and expression, they also introduce new risks like the “cyber bullying” linked to social anxiety and depression148,149.

Many electronic health records now offer patient-centred portals that provide opportunity for pa-

14 tient-physician interaction and education, which makes these innovations a potentially powerful tool to improve adolescent asthma care150. Education is an ongoing process and should be an integral part in most consultations. The essential components for this include: skills training to use devices effectively, encouraging adherence with medications, appointments and other medical recommendations, within an agreed management strategy, asthma information, training in guided self-management, a written asthma action plan to show how to recognize and respond to worsening asthma and regular review by a health care provider151. Multiple internet resources are now available (Table 2), which are very useful, but these should be customized for the needs of the individual during consultation.

Patients who receive an interactive, comprehensive education program have improved their quality of life have a better management of asthma and better control of the disease compared with those receiving just the usual care. In a recent study on school-based asthma interventions significant improvements were seen in asthma symptoms, rescue inhaler use, health care utilization, school absen- teeism, and physical activity limitations152. An interactive group education program offered to children with asthma at school has merit as a practical, cost-effective, peer-supportive approach to improve health outcomes153.

Basic interventions (Table 3) include simplifying medication regimens and maintaining continuity of care with the same provider, providing asthma self-management, education sessions and individualized asthma action plans154. Creating a partnership with patients through a shared decision-making (SDM) approach, in place of a clinician decision making (CDM) approach, may be effective with adolescents155. Moreover higher levels of family support were found to ameliorate negative attitudes toward medications and health care providers and were associated with improvement in asthma control145Interventions involving “reminders” to take medications may be helpful, as this group frequently blames forgetfulness for non-adherence147.

15 CONCLUSIONS

Progress is being made on management of asthma in adolescence (Table 4). At least in developed countries, most adolescents with asthma should lead a normal life. Unfortunately, sometimes young people still have impaired quality of life because of their disease and some even die because of unacceptably poor standards of care. So clinicians in the field need to raise standards.

Good asthma control is not about the newest treatment, but it is about getting the basics right: getting the diagnosis right; giving an appropriate level of treatment; and making sure the adolescent and family understand the disease. Although adolescents with asthma can be very challenging, unsuccessful treatment often results from failings of clinicians. The young person needs to understand the condition and its treatment and to adhere to treatment, understanding that lifelong therapy may be needed. Time spent on discussion is very worthwhile. Many patients (and many doctors), have low expectations of what can be achieved with appropriate therapy. The young person’s expectations must be raised, including that high level sports and good school attendance are possible, provided they can comply with their asthma management plan.

The main problem with adolescents is poor adherence, and more research is needed to develop helpful strategies. Incentive-based medication adherence interventions can be very effective, but are yet understudied. The development of interventions which lead to sustained, not merely short-term adherence, is a significant challenge. When poor asthma control is related to poor adherence, the use of electronic devices for preventer inhalers, for example with audiovisual reminders, is one way whereby improved adherence could be achieved. Moreover electronic monitors provide objective and detailed adherence data and may be useful in assessing inhaler competence. Strong peer support networks can help adolescents deal with the day-to-day struggles that having asthma forces them to face. Social isolation and gaps in social support, particularly from peers, is a longstanding problem, and is especially pertinent for adolescents. Online support intervention through asthma chat rooms or forums can be a very powerful way to minimise isolation. Social media plays an increasing role in adolescents’ daily lives and caregivers should

16 learn how to deploy them to improve interactions. However further research is needed to systematically measure their impact on health, develop evidence-based frameworks and achieve validated interventions using social media to improve adherence. Finally, the physician’s main effort should be directed to win the trust of their teenage patients and develop individualized programs to achieve good asthma outcomes whilst facilitating the normal developmental tasks of puberty and adolescence.

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