Why do Finland and Sweden differ when it comes to trends in asthma medication and hospitalisation for children aged 0-4 years?

Abstract

The 1980s saw a drastic reduction in the number of children hospitalised for asthma in Scandinavia, and this mirrored the increased use of inhaled corticosteroids (ICS) by those aged 5-19.1, 2 In contrast, wheezing remained common in Swedish children aged 0-4 years,2 as ICS were less effective in this age group. The number of days that children and adolescents aged 5-19 spent in hospital due to asthma, from 2005 to 2014, remained low in Finland and Sweden.3 In addition, paediatric deaths from asthma were very rare in both countries.4, 5 Early Swedish studies carried out by my group on asthma hospitalisation, and the use of asthma medication, were mainly based on regional data.1, 2 However, Scandinavian patient and drug registers now allow us to study the trends in these at a national level. It is interesting to study changes in asthma medication in its own right, but there is a particular clinical interest in relating these data to measures of asthma morbidity. In this issue of Acta Paediatrica, Kivistö et al report the findings of a study that used national register data to explore paediatric trends in dispensed asthma medication in Finland and Sweden from 2006 to 2017.6 The study provides a valuable complement to the authors’ previous report on paediatric asthma hospitalisation in the two countries from 2005 to 2014.3 The current study shows similarities between Finland and Sweden, as well as some differences. The dispensing trends for ICS for children and adolescents aged 5-9, 10-14 and 15-19 years were similar in Finland and Sweden. However, children aged 0-4 years were 1.5 times more likely to be given ICS if they lived in Sweden. This may reflect the fact that Swedish clinicians often treated viral wheeze episodes with short periods of high-dose ICS, starting at the first sign of a cold and then for 7-10 days. In contrast, leukotriene receptor antagonists were more commonly dispensed in Finland. The difference between the countries probably reflects that Finnish paediatricians were less inclined to use ICS for those aged 0-4 than their Swedish colleagues and, to a greater extent, preferred leukotriene receptor antagonists. The number of children who were dispensed short-acting beta-2-agonists (SABA) increased in both countries, particularly in children aged 0-4 years and those living in Finland. The increase in this youngest age group is not easily explained, but one factor could be that the higher prevalence of ICS dispensing in Sweden lowered the need for SABA. My clinical experience is that ICS are often less efficacious in young wheezers, and it is not surprising that hospital admissions for wheezing illness have remained quite common in children aged 0-4.2, 3 Furthermore, it could explain why treatment is still very much based on symptom relief with beta agonists. Having said that, it does not explain the increased use of relievers. Although there was still a high absolute incidence of hospitalisation among young wheezers in Finland and Sweden from 2005 to 2014,3 Kivistö et al noted a decrease in hospitalisation for asthma for those aged 0-4 years, especially in Finland. One explanation could be that there was a shortage of facilities for in-patient treatment, possibly combined with an active desire to treat the youngest children at home with metered dose inhalers and a spacer.7 A logical consequence of this would have been increased prescriptions for SABA. If so, the increase in SABA dispensing would have been a consequence of the decline in hospitalisation, rather than an explanation for why it happened. The drug registers that Kivistö et al used are often called prescribed drug registers. However, this is not a completely accurate term, as the data they contain are based on medication that was actually dispensed by pharmacies rather than prescribed by clinicians. Although most parents would pick up medicine prescribed for their child, these figures cannot be regarded as reflecting medication that was prescribed or taken. Electronic prescriptions have been mandatory in Finland since 2017 and Sweden is moving towards this, although their advanced plans have been temporarily postponed.8 Once the drug registers are based on just electronic prescriptions, they will be able to provide full data on prescribed medication. Various registers could then be linked at a national level and focus on associations between prescriptions, dispensed medication and hospitalisation. Of course, we still would not know whether the prescribed and collected medication had been taken. In the meantime, studies like the ones reported by Kivistö et al in this area provide useful information on the ongoing trends, based on the best data that are currently available.3, 6 The author has no conflicts of interest to declare.