The increase of asthma prevalence has levelled off and symptoms decreased in adults during 20 years from 1996 to 2016 in Helsinki, Finland

Abstract

Background: Mortality and hospitalization due to asthma have decreased in many European countries, but asthma symptoms still cause a lot of morbidity and costs. Objectives: We evaluated prevalence trends of asthma, asthma symptoms and allergic rhinoconjunctivitis in adults aged 20-69 years during a 20-year period from 1996 to 2016 in the city of Helsinki, the capital of Finland. Methods: Three cross-sectional postal surveys were conducted in random population samples 10 years apart. In 1996, 2006 and 2016, a total of 6062 (response rate 75.9%), 2449 (61.9%) and 4026 subjects (50.3%) took part, respectively. Results: In all responders, the prevalence of physician-diagnosed asthma was 6.6% in 1996, 10% in 2006 and 10.9% in 2016. The prevalence increased from 1996 to 2006, but stabilized from 2006 to 2016, both in men and women and in smokers and non-smokers. The prevalence of current asthma (8.5% in 2006 and 8.8% in 2016) and of asthma with rhinoconjunctivitis (7.6% in 2006 and 7.5% in 2016) remained also at the same level. Allergic rhinoconjunctivitis decreased significantly from 2006 (42.7%) to 2016 (39.0%, p = 0.004). Those with physician diagnosed asthma reported significantly less symptoms in 2016 compared to 2006 and 1996, although there was no change in smoking habits or medication use. Young asthmatics (20-29 years) without rhinoconjunctivitis reported least symptoms. Conclusion: Previously observed increase of physician-diagnosed asthma prevalence in adults seems to be levelling off in Helsinki, and patients have fewer symptoms than 20 years ago. In addition, allergic rhinoconjunctivitis is less frequent than 10 years earlier.

Differences in diagnostic patterns of obstructive airway disease between areas and sex in Sweden and Finland - the Nordic EpiLung study

“…In the current study, the prevalence of physiciandiagnosed asthma was higher in both Sweden and Finland than in the 1990s when the prevalence was 7.8% in Sweden and 5.9% in Finland (7,36). However, in Northern Sweden an ongoing increase was reported from 1996 to 2006 and further to 2016 (7), while in Helsinki an increase in asthma diagnosis was found until 2006 (9), but leveling until 2016 (11). The introduction of the Finnish asthma program (12) and the implementation of asthma/COPD clinics and national guidelines in Sweden (46) may have contributed to better recognition of asthma in primary healthcare, which might be reflected in our findings.…”

“…In Finland, the study was performed in Helsinki, the capital of Finland located in the southern part of the country, where 50.3% (n ¼ 3,998) responded (11) and in Sein€ ajoki-Vaasa, an area in western Finland, where 52.5% (n ¼ 4,173) responded (40).…”

“…In Sweden, both an increase and a leveling of prevalence of physician-diagnosed asthma have been reported during the last decades (7,8,10). In Helsinki in Finland, the prevalence of physician-diagnosed asthma increased until the 2000s (9) but leveled during the last decade (11). This increase in prevalence in Finland may be associated with an increased awareness of asthma in primary health care attributed to the implementation of a specific national asthma program (12).…”

“…Although respiratory symptoms are common in the general population (27)(28)(29)(30), some studies suggest a decreasing or leveling trend of respiratory symptoms, chronic bronchitis (CB) and obstructive lung diseases during the last decades (7,8,10,11,25,31,32). This decrease is partly a result of a decrease in tobacco smoking (7,8,31).…”

Helsinki by nature: The Nature Step to Respiratory Health

“…For example, in 2013–2015, the prevalence of use of allergy diets decreased by 43% in day care centres in the Helsinki Capital area [65 ]. The Finnish disease surveillance system is showing signs that the epidemic is slowing down as the asthma and allergic rhinitis prevalence is levelling off [66 ]. Experience shows that medical communities and societies can lessen the disability and costs caused by these disorders and improve public health.…”