Changing prevalence of current asthma and inhaled corticosteroid treatment in the UK: population based cohort 2006-2016.

BACKGROUND: Asthma is the most common respiratory disorder in the UK, yet we have incomplete knowledge on the prevalence of current disease, treatment and exacerbations.

METHODS: We used UK electronic healthcare records, 2006-2016, to estimate the prevalence of current asthma by year, gender and age (<5, 5-11, 12-17, 18-24, 25-54 and ≥55 years), and the proportion prescribed inhaled corticosteroids (ICS) and additional asthma-therapy, treated for exacerbations and other asthma care markers.

RESULTS: Overall current asthma prevalence was 6.5% in 2016 (7.2% in 2006). Prevalence fell in those under 45 years. The lowest prevalence and largest absolute decrease was in children under 5-years. In 2016, 80% of current asthma patients were managed on ICS, (65% in 2006); this increase occurred in all ages, primarily due to an increase in low-dose ICS. During this time there was an increase in all age-groups in the proportion prescribed additional asthma-therapy, treated for an exacerbation within primary care, given an annual asthma review or management plan. Hospitalised exacerbations showed minimal change over time.

CONCLUSION: Asthma remains highly prevalent and a significant healthcare burden. In those with a diagnosis, there was an increase in ICS prescriptions and treatment of exacerbations across all age-groups. This may reflect a trend towards more aggressive asthma management within primary care. An apparent decline in prevalence was observed in those aged under 45 years, particularly in children under 5 years.