Determinants of Respiratory Health

Respiratory symptoms and diseases are common, and behind them are numerous factors such as environmental exposures, habits, and genetics. Our aim was to analyse the impact of socioeconomic and physical determinants and individual behaviour on respiratory health at the population level by comparing language groups in Western Finland and childhood environments in Western and Southern Finland. With knowledge of the risk factors of respiratory diseases, there is a possibility to prevent the development of respiratory disease.

The study was based on the cross-sectional FinEsS postal survey sent in February 2016 to a random sample of 8,000 persons aged 20 to 69 years in Western and Southern Finland. The response rate was 52.5% in Western Finland and 50.3% in Southern Finland. Analyses comparing language groups included 3,864 subjects from the Western Finland cohort, of which 2,780 (71.9%) were Finnish speaking and 1,084 (28.1%) were Swedish speaking. Analyses comparing childhood environment included 3,767 subjects, of which 2,143 (56.9%) were exposed, and 1,624 (43.1%) were not exposed to childhood farming environment. Southern Finland survey was used to validate childhood environment comparisons and combined data from Western and Southern Finland for prevalence estimates and age-standardised prevalence rates.

Our study showed that Finnish speakers had a higher prevalence of dyspnoea mMRC ≥2 than Swedish speakers, meaning they had to walk slower than other people of their age on the level because of breathlessness. Dyspnoea mMRC ≥2 odds were higher with smoking and obesity, whereas native language or skill level did not increase the odds. Finnish speakers had higher body mass index (BMI); were physically inactive; smoked more often; had more frequent occupational exposure to vapours, gases, dust, or fumes (VGDF); and had lower socioeconomic status based on occupation than Swedish speakers.

Finnish speakers were more likely to be diagnosed with chronic obstructive pulmonary disease (COPD), diabetes, heart failure, reflux disease, chronic kidney disease, and painful conditions than Swedish speakers. Asthma prevalence was 11.5% in both language groups. The prevalence of multimorbidity was higher for Finnish speakers aged from 60 to 69 years than Swedish speakers. In younger age groups, asthma prevalence was higher for Swedish speakers. Subjects who were smokers, obese, or physically inactive, and those with lower skill levels had higher odds for multimorbidity than others. We proposed a tool for patient education that describes the relationship among smoking, inactivity, and obesity to multimorbidity. Those with childhood exposure to farming smoked less, exercised more, had lower socioeconomic status based on occupation, and had more occupational exposure to VGDF than those with non-farming childhood. Prevalence of allergic rhinitis was lower among those with childhood exposure to farming environment than those without this exposure. In contrast, prevalence of longstanding nasal congestion was higher in those subjects with farming than non-farming childhood environment. Childhood exposure to farming environment influenced the age at asthma diagnosis. The odds for asthma were lower before and higher after the age of 40 years with childhood exposure to farming environment.

Late-diagnosed asthma is associated with NSAID-exacerbated respiratory disease (N-ERD). Estimated prevalence of N-ERD was 1.4% in Finland. Heredity and cumulative exposure to smoking, passive smoking, or occupational exposure to VGDF were associated with higher odds for N-ERD. Childhood exposure to farming environment increased the age standardised rate of N-ERD by 1.2 times when compared to non-farming childhood environment.

To conclude, our research showed that both belonging to a language group or growing up in a farm was associated with behaviour, socioeconomic status, and environmental factors at a population level, and this affected the respiratory health. Respiratory health inequalities and preventable differences in outcomes do exist in our study populations. These differences might remain undetected when looking at disease prevalence of asthma or multimorbidity alone.