Issues in adolescent asthma: what needs? · play or gamesperiods are to help identify un-diagnosed asthma in teenagers. A survey of adolescent athletes suggested that screening followed

Thorax 1996;51(Suppl 1):S13-S17

Issues in adolescent asthma: what are theneeds?

John F Price

Although asthma is increasing in teenagers itis often not recognised. This may be partly dueto a lack of perception of the disease and partlyto a reluctance to seek medical advice. A greaterawareness of asthma in schools and healthchecks for teenagers in general practice mayhelp to improve diagnosis. In addition, strat-egies to discourage cigarette smoking should betargeted at young people with asthma. Asthmaeducation is important, but in itself will notresolve the non-compliance with treatment that

Asthma education is important, but initself will not resolve the non-

compliance with treatment that iscommon in adolescents.

is common in adolescents. Treatment plansneed to be negotiated, not dictated, and aremore likely to succeed with parental and peergroup support. One barrier to compliance is a

general antagonism to regular daily medication.Teenagers are more likely to comply with onceor twice daily regimens than with treatmentthree or four times daily. Inhaled broncho-dilator therapy is preferred to oral therapy,although oral anti-inflammatory compoundsmay have advantages in compliance.

Department ofChild Health,King's College Schoolof Medicine andDentistry,London, UKJ F Price

Recognition of asthmaThere are several reasons why asthma oftengoes unrecognised and tends to be undertreatedin teenagers. Disraeli (British statesman andwriter, 1804-81) is alleged to have said that"youth is a blunder", a phrase that epitomisesthe traditional adult concept of adolescence as

Table 1 Prevalence of asthma in adolescents

Country Year of study Age (years) Prevalence (%)

New Zealand' 1991 12-15 32-38Australia2 1992 12-15 16-5Netherlands3 1989 10-23 19Finland4 1991 15-16 2-8

Table 2 Mortality due to asthma in the UK between 1990 and 1992'Age (years)

0-4 5-9 10-14 15-19

Population (millions) 3 54 3-26 3-13 3-11Boys 22 9 31 50Girls 12 5 12 37Total 34 14 43 87

a disagreeable period of turmoil, awkwardness,rebelliousness, and unpredictability, to betolerated then quickly forgotten. The otherfamiliar aphorism detrimental to the care ofadolescents is that "children grow out of theirasthma". Asthma is almost as common inadolescence as it is in young children and morecommon than it is in adults. In New Zealand32-38% of 12-15 year olds had experiencedwheezing illness during the year preceding thestudy.' Diagnosed asthma occurred in 16-5%of Australian children of the same age.2 In theNetherlands the figure was 19% for a groupaged 10-23 years.3 There are approximately4-2 million teenagers in the UK (8-4% of thetotal population). If the prevalence of asthmain this group is the same as it is in The Neth-erlands, then more than 800 000 of them haveasthma. In Scandinavia the prevalence ofasthma in adolescents is low. However, in Fin-land it increased from 1% in 1977 to 2-8% in1991 (table 1).4

Fortunately, asthma deaths are uncommonin adolescents, but in the UK between 1990and 1992 three times as many children aged10-14 years and six times as many aged 15-20years have died ofasthma as those aged between5 and 10 years. Furthermore, asthma deathswere more frequent in boys than girls, but thegap narrowed in the late teens (table 2).5The discrepancy between the data in table 1

- which indicates a prevalence of wheezingillness of over 30% in New Zealand obtainedusing video techniques and a standardised writ-ten questionnaire' - and that of 16-5% fordiagnosed asthma in Australia2 suggests thatasthma may be underdiagnosed in youngpeople. Further evidence comes from the studyof the prevalence of asthma in young people inThe Netherlands. Screening by questionnaireand spirometry identified 19% of the popu-lation studied as having asthma, but asthmahad been recognised by the general practitionerin less than half of them. Male sex, a pasthistory of "bronchitis", and a family history ofatopy increased the likelihood of recognitionof asthma.3 Possible reasons for the failure todiagnose asthma are that young people mayhave poor perception of asthma symptoms orthat they may be reluctant to consult theirdoctor about them.

It is well known that some patients withasthma are unaware of airways obstruction orunderestimate the degree of its severity. Al-though no studies specific to teenagers havebeen carried out, Rubinfeld and Pain in-vestigated the perception ofwheezing by adultsin whom asthma was induced by bronchialchallenge. Some were found to be quite un-

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aware of any symptoms when their forced ex-piratory volume in one second (FEV1) was lessthan 50% ofpredicted values. Others felt mildlywheezy with an FEVy of less than 30% ofpredicted.6Four years ago Market and Opinion Re-

search International (MORI) carried out aqualitative survey of adolescents with asthmaon behalf of the UK National Asthma Cam-paign.7 Forty six young people with asthmaaged 13-16 years were recruited from schoolsthroughout the UK. Groups of between sixand nine individuals took part in topic guideddiscussions. It emerged that only two of the46 attended an asthma clinic, only 25 hadundergone peak flow measurement at sometime, and most had poor knowledge of theirasthma and limited understanding of its man-agement. Furthermore, many relied heavily onpharmacists to explain their medication. Thesurvey revealed a reluctance by these teenagersto visit their general practitioner or attend out-patient clinics.One place where undertreated or un-

diagnosed asthma might be recognised is atschool. About half of all school age childrenwith asthma are unable to complete gamesperiods because of asthma.8 Unfortunately,many teachers in the UK have little knowledgeof the relationship between asthma and ex-ercise. In one survey over half of the teachersquestioned considered that asthmatic childrenwere less competent at sporting activities butfew were aware that this was because the phys-ical activity provoked wheezing or that it couldbe prevented by pretreatment with a i agonistbronchodilator.9 Teachers need more struc-tured information if their observations duringplay or games periods are to help identify un-diagnosed asthma in teenagers. A survey ofadolescent athletes suggested that screeningfollowed by formal exercise testing might beone way of identifying asthma. Previously un-recognised exercise-induced asthma was foundin 29% of adolescent athletes identified bymedical history and spirometry to be at risk.'lFormal exercise testing has the disadvantagethat it is very time consuming if applied to largenumbers of children. Also, it may not revealasthma that has been asymptomatic for severalmonths."An alternative approach is to invite adoles-

cents to general practices for health checks.This offers the opportunity both for recognisingasthma and for giving advice about other healthissues such as diet, physical activity, contra-ception, alcohol consumption, and cigarettesmoking.The willingness of young people to attend

health checks was tested recently in three UKgeneral practices - one in an inner city area,another in a country town, and a third in arural area. The aim of this particular study wasto address the issue of cigarette smoking but theinvitation made no special mention ofsmoking.Up to three invitations were sent out to eachindividual. Perhaps surprisingly, the responseof 13, 15, and 17 year olds was very positiveand 73% of those invited attended for check-ups.12

This and another study of screening of adol-escents in general practice, which achieved a50% attendance on a single invitation, 3 suggestthat, if approached personally, teenagers arewilling to listen to advice about their health.An unexpected bonus, expressed by the prac-tice staff who conducted the first study, wasthe opportunity to begin a good adult-typerelationship with the teenagers based on theconcept of a healthy lifestyle.'2

Self-image and risk takingThe adolescent environment is wider and oftenmore hostile than that of the younger child. Tobe able to cope with the new environmentadolescents must develop certain attributessuch as personal autonomy and reduced de-pendency on parents and family, which is nat-ural in early childhood, and increased intimacywith peers based on a combination of pre-adolescent experiences and newly acquiredautonomy. At the same time adolescents aredriven by and must respond to new and power-ful sexual impulses. The fierce desire to achieveindependence from pre-adolescent family tiesis matched by an intense aversion to beingdifferent from the peer group. An almost in-evitable consequence of this is risk taking be-haviour which tests new boundaries inrelationships with family and peers.

Asthma may make it more difficult foradolescents to arive successfully at

competent adulthood ...

Asthma may make it more difficult for adol-escents to arrive successfully at competentadulthood for several reasons including: (1)continued dependency on parents becauseadolescents and their parents attend outpatientor asthma clinics together and parents sharethe management ofthe adolescent's disease; (2)coughing or wheezing during physical activitysuch as sport and dancing; and (3) the need touse highly visible treatment which makes youngpeople with asthma different from their friendsand may lead to isolation. In addition, thedesire not to be seen taking treatment maycontribute to non-compliance with the treat-ment.

Investigation of self-image, self-esteem, andcognitive and emotional disturbance in asth-matic adolescents has produced differingresults. One study using the Offer Self-ImageQuestionnaire failed to demonstrate anydifferences between asthmatic adolescents seenin a private outpatient allergy practice and non-asthmatic controls. In fact, the self-image ofthe asthmatic girls was better in some respectsthan that oftheir non-asthmatic counterparts. 4On the other hand, a study of 12-18 year oldswith chronic diseases including asthma, usinga questionnaire compiled from the Beck De-pression Inventory and the Rosenberg Scale ofSelf-Esteem, found they had higher depression

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Issues in adolescent asthma: what are the needs?

scores and lower self-esteem than healthy agematched controls.'5 All of the children in thesecond study had been admitted to hospital atleast twice during the previous year and so mayhave represented a group with more severedisease than in the first study. This impressionis borne out by the results of a third studywhich showed that teenagers with mild asthmadid not have any greater cognitive or emotionaldisturbance than those without asthma. How-ever, irrational beliefs, anxiety, depression, andhostility were strongly associated with severeasthma.'6

Cigarette smoking is a common risk takingactivity in teenagers. Most adult smokers takeup smoking as teenagers and the earlier childrenstart smoking the less likely they are to give itup.'7 A survey conducted in the UK in 1990concluded that 27% of girls and 26% of boysin the fifth year of secondary school (aged15-16 years) were smoking regularly (at leastone cigarette per week).'8 Cigarette smoking isalmost as common among adult asthmatics asit is in non-asthmatic subjects. Adolescentswith asthma past or present may represent agroup particularly likely to take up smoking. Aquestionnaire used to discover perceptions andbeliefs about smoking in 13-16 year olds re-vealed that those with a past history of asthmahad a more positive attitude towards cigarettes,a self-image more closely linked with their per-ception of smokers, and a stronger intentionto become smokers themselves than non-asth-matics.'9The penalties for taking up smoking at a

young age, such as increased risk of lungcancer,20 reduced asthma control and, for girlswho smoke during pregnancy, a major risk ofabnormal lung function in their infants,2' areirrefutable. A general awareness of these dan-gers does not seem to be sufficient to discourageteenagers from smoking. Other strategies areneeded and it is encouraging that many teen-agers seem to welcome an initiative from theirgeneral practitioners. Counselling in early adol-escence by family doctors and practice nursescould potentially reduce the uptake of cigarettesmoking by young asthmatic patients. Theinitial response of adolescents who attendedhealth checks in the general practice studydescribed earlier was that 60% of the smokersmade an agreement with the practice doctor ornurse to give up smoking.'2

The diagnosis of asthma ... is likelyto provoke intense emotions and beliefs

in adolescents.

Education and complianceAn approach that assumes that the teenagerwill follow the clinician's directions if asthmais explained and treatment recommendationsdemonstrated is often unsuccessful." In-telligence, education, and the ability to under-stand information about the nature of asthmabears little relationship to compliance. Even

when clear written advice is given, as many as75% of asthmatics do not take their medicationcorrectly."The diagnosis of asthma, whether symptoms

have just developed or the asthma is long-standing but previously unrecognised, is likelyto provoke intense emotions and beliefs inadolescents. It may be very difficult to expressthese concerns either to parents or to doctorsand reactions may take the form of anger, self-blame, fear, reduced sense of self-esteem, ordenial. Most teenagers prefer to view asthmaas episodic and find it hard to accept the needto take regular medication. A vital first stepin management is to discover the teenager'sanxieties about asthma and its treatment. Ques-tions inviting a yes or no answer do not achievethis and open ended questions such as "Whatworries you about having asthma?" or per-missive questions such as "Lots of teenagerstell me that they are unhappy about takingtreatment every day. What sort of things worryyou about taking treatment regularly?" arelikely to be much more revealing."4 This sortof discussion helps to establish a two-way flowof information that moves towards the ne-gotiation of a contract ofmanagement betweenthe physician and the teenager. Negotiation isimportant because it will give the teenager someauthority and less of a feeling that asthmaand its treatment will impede progress towardsadulthood. Where possible the clinician shouldenlist the involvement and support of parentsin such negotiations as effective parental in-volvement in the healthcare of teenagers willimprove compliance with treatment regimens.

Asthma management is also morelikely to succeed if it is combined with

... peer support.

Asthma management is also more likely tosucceed if it is combined with that most power-ful ofinfluences - peer support. Support groupsgive the opportunity for teenagers with asthmato share the burden of their illness and to seehow others cope with their parents and peersas well as with their asthma attacks. An exampleis the "Support for Asthma Youth" initiativesponsored by the Asthma and Allergy Found-ation of America. Each group has a core ofteenagers with asthma supported by a res-piratory nurse or asthma educator and a phys-ician who gives advice. This particular networkproduces written and telephone advice andorganises group sessions to increase the under-standing of asthma. The group sessions alsooffer the opportunity to share practical tips onasthma management. As adolescents employsome of the learning tools of childhood, in-cluding play, the most effective methods foreducation have proved to be role play andlearning games. Information in the form ofbooklets and videos is a useful supplement to,but not a substitute for, personal contact. Thesame applies to treatment plans. A plan ofasthma management once worked out with the

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Price

Table 3 Partnership in asthma management

Recognise expectations and concernsNegotiate contracts, enlist family supportKeep the treatment plan simpleWrite down what to do if the asthma gets worse, improves, or

there is an attackReview and reward efforts

teenager and his parents should be writtendown. Simple treatment plans are the mosteffective. They need to contain three essentialelements: what to do if the asthma gets worse,how to reduce treatment if the asthma im-proves, and how to manage an acute attack.This gives teenagers some responsibility forand control over their disease, but they alsoneed to know when to seek medical help (table3).

TreatmentAdministration of asthma medication directlyto the airways by inhaler confers the greatadvantage that small doses can be given, thusreducing the risk of side effects. The largevolume (750 ml) spacer device with a one-wayvalve is an efficient, easy to use delivery system.However, for teenagers, it is cumbersome andembarrassing. It cannot be carried un-obtrusively and, in the teenager's bedroom, itis immediately obvious to friends. The un-modified metered dose inhaler (MDI) is mucheasier to conceal and tends to be more popularwith teenagers. Unfortunately it is seldom usedproperly. More than two thirds of adults2526and half of children27 with asthma do not usethe correct method even after instruction.A study of MDI use by junior paediatric

medical staff in a New York teaching hospitalhighlights the problem. When asked to dem-onstrate inhalation via an MDI 48% did notshake the inhaler and 40% failed to exhalebefore use; 29% actuated the inhaler more thanonce during a single breath and 54% did nothold their breath after inhalation.28 This lackof knowledge and expertise among asthmaticsand clinicians is striking, but it is probable thateven those teenagers who know how to use theMDI correctly do not do so when they are withtheir peers. Although small and convenient tocarry, the MDI becomes very obvious if theproper inhalation technique is used - first ex-haling, then inhaling with the head tilted back,and finally holding the breath after inhalation.We have little specific information about thetechniques used by teenagers to inhale med-ication via MDIs, but the least easily observedmethod is certainly not the most efficient.

Table 4 Preventive medication for asthma (France,Germany, Italy, USA, UK)

Age (years)

0-9 10-19 20+

Population (%) 13 12 75Prescriptions (%)

Cromoglycate 46 22 78Inhaled corticosteroids 10 12 78Ketotifen 36 15 49Theophylline 4 5 91

Source IMS AG (1994).

Two other factors likely to influence thewillingness of teenagers to take medication arefrequency of administration and concern aboutside effects. Four classes of compound arewidely used for regular or preventive med-ication in children and adolescents withasthma: sodium cromoglycate, inhaled cortico-steroids, ketotifen, and theophylline. Thereare wide variations in prescribing habits indifferent countries but when data from France,Germany, Italy, USA, and the UKwere pooled,22% of all prescriptions for cromoglycate, 12%for inhaled corticosteroids, 15% for ketotifen,and 5% for theophylline were for 10-19 yearolds who comprise about 12% of the totalpopulation (table 4). It is recommended thatsodium cromoglycate be taken four times aday. There must be considerable doubt aboutcompliance with a regimen with such a highfrequency of administration.29 Compliancewith a regimen of inhaled prophylactic med-ication in 9-16 year olds was found to beinversely related to the number of doses pre-scribed per day. The percentage of days whenmedication was taken as prescribed decreasedfrom 71% for twice daily medication to 18%for four times daily medication.30

Inhaled corticosteroids are currently themost effective treatment for moderate andsevere asthma in all ages and need be takenonly twice daily. However, compliance withinhaled corticosteroid treatment may be in-fluenced by anxiety about side effects. Suchconcerns about possible adverse effects, par-ticularly effects on growth, are often expressedby the parents of young children with asthma;we do not know whether this is something thatalso worries teenagers. A physiological delay inthe onset of puberty is often seen in asthmaticpatients irrespective of the severity of diseaseor its treatment. It is conceivable that asthmaticteenagers who are smaller and less well de-veloped than their peers might worry moreabout the possible adverse effects of treatmenton their growth. However, what little evidencewe have in adolescent asthma suggests thatfears on growth suppression by inhaled corti-costeroids during adolescence are unfounded.In a multicentre study in The Netherlands3'the growth of 40 asthmatic teenagers treatedwith budesonide 0 6 mg/day for a median of22 months was compared with the growth ofasthmatic and non-asthmatic controls. Asth-matic boys grew more slowly than their age-matched non-asthmatic peers irrespective ofwhether or not they were taking inhaled corti-costeroids. This is compatible with their havinga later onset of pubertal growth. However, thegrowth rate of asthmatic boys and girls treatedwith inhaled corticosteroids was no differentfrom that ofthose who received only a fi agonistbronchodilator." Young people may also as-sociate "steroids" with the androgenic varietyused by some athletes. Although these anxietiesabout the side effects of inhaled corticosteroidsare without foundation, they may still be abarrier to compliance.

Oral compounds that are taken only twicedaily have potential advantages for treatmentcompliance in teenagers. This may help to

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Issues in adolescent asthma: what are the needs?

Table 5 What are the needs?

Health checks, general practitioners, and schoolsNon-smoking strategyPeer support groupsAgreed, simple, written treatment plansJoint clinics for severe disease

explain the frequent prescription of ketotifento asthmatic adolescents. Although useful inatopic pre-schoolchildren, clinical trials havenot shown this compound to be highly effectivein older children and adults. Its popularity mayin part be attributed to ease of administration.Slow-release theophyllines have the same ad-vantage of ease of administration, but the needfor frequent dose adjustment during rapid pu-bertal growth32 makes their use impractical inmany teenagers.The leukotriene receptor antagonists, which

are likely to become available on prescriptionfor adults and adolescents in the near future,are also orally active. Our understanding ofthe role of the leukotrienes in childhood andadolescent asthma is still rudimentary. Levelsof cysteinyl leukotrienes are raised during andone month after asthma attacks in young chil-dren, so one can speculate that upregulationof the arachidonic acid metabolic pathway maycontribute to persistent inflammation of theairways in young asthmatics." We must awaitthe outcome of appropriate clinical trials beforewe know whether leukotriene receptor ant-agonists have a place in the treatment ofyoungpeople with asthma. Certainly, an orally activeprophylactic agent that can be taken twice a

day is likely to appeal to teenagers, and mayimprove compliance.

Concluding remarksIn the UK most children with asthma do notattend hospital clinics and continuity of care isprovided by their general practitioner. How-ever, those with severe asthma, most of whomwill not grow out of their symptoms, needhospital-based care as well. As they progress

through adolescence teenagers become in-creasingly uncomfortable in paediatric wardsand outpatient clinics. They need clinics wherethey can meet the chest physician who will takeon their care before they transfer to a clinic foradults (table 5).

Adolescent asthmatic patients are adistinct group ofpatients withdifferent treatment requirementsfrom either paediatric or adult

patients.

Adolescent asthmatic patients are a distinctgroup of patients with different treatment re-

quirements from either paediatric or adultpatients. It is important that physicians re-

cognise adolescent needs and the importance of

regular health checks, smoking, peer pressure,and the negotiation of treatment plans in thisgroup of patients.

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