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studies conducted throughout the United Kingdom, Australia and New 7-ealand, (Robertson,
Heycock et al. l99l; Peat, van den Berg et al. 1994; Rona, Chinn et al. 1995; Mitchell and
Asher 1997; Asher and Grant 2006). In the 'Global Burden of Asthma' report (GINA 2004)
the proportion of the population said to have 'clinical' asthma in New Zealand is given as
l1.l%o and in England (the country I did the research reported in this thesis) is given as
l5.3%o. The case fatality rate for asthma is 4.6/100,000 asthmatics in New Zealand and
3.211N,000 asthmatics in England. In the 2006 ranking for asthma mortality from one
(highest) to 68 (lowest) New Zealand appears at 17 and England at 26. The International
Study of Asthma and Allergies in Childhood (ISAAC), (Weiland, Bjorksten et al.2004) and
the European Community Respiratory Health Survey (ECRHS), (Anonymous 1996) asked
about self reported wheezing in the previous twelve months as one of their core questions,
having demonstrated this had good specificity and sensitivity for diagnosis of asthma. In 13-
14 year old children, England and New Tnaland were ranked six and seven out of 84 countries
where the listing was from one being the highest percentage of positive responses to 84 being
lowest percentage of positive responses (Anonymous 1998). Furthermore, New Zealand
ranked second when the symptom prevalence of wheeze in 13-14 year olds was determined
by responses to a video questionnaire in 44 countries (Anonymous 1998).
In addition to community prevalence, asthma is a major cause of hospital admissions for
children, particularly noticeable in younger age groups. Admission rates had been increasing
through the 1970s, 1980s and early 1990s (Anderson, Bailey et al. 1980; Jackson and Mitchell
1983; Mitchell 1985; Hyndman, Williams et al.1994) with possible stabilisation or reduction
in the most recent years (Kemp and Pearce t997; British Thoracic Society 20OI; Akinbami
and Schoendorf 2002). There were two major epidemics of asthma mortality and New
7-ealand featured highly in both. The first mortality increase was observed in several countries
through the 1960s and included Australia, England, Norway, Scotland, Wales and New
7*,aland. The second epidemic was seen in New 7*,aland alone when mortality rates reached
4.1/100,000, which appeared linked to the use of the relatively non-selective B-2 agonist
'Fenoterol'. A 'Fenoterol' case control study was undertaken which looked at ll7 patients
between 5-45 years dyrng of asthma between 1981 and 1983. Each index case was matched
with four controls and the use of 'Fenoterol' gave a relative risk of death of 1.59, slightly
higher in females at 1.65 compared to males at l.M. However it was greater in the patients
who were less than 20 years of age with an odds ratio of 2.08 (Crane, Pearce et al. 1989).
Fenoterol was subsequently withdrawn from the drug tariff and, coinciding with the greatly
reduced use after 1990, there was a significant reduction in the number of deaths (Crane,