Myopia prevalence in Finland doubled from 1930s to 1950s birth cohorts and is linked to educational attainment
Marja‐Liisa Franssila, Klaus Nordhausen, Jukka Moilanen, Niko Setälä, Olavi PärssinenAbstract
Purpose
The purpose of this study is to investigate the prevalence of myopia and factors associated with the increase of myopia prevalence in Finland between two generations and discuss the reasons why myopia has not increased similarly as in many Asian countries.
Methods
A questionnaire assessing factors potentially related to myopia was sent out in 1983 to all residents born in 1957 (aged 26 at the time) and 1937 (aged 46) residing in the Jyväskylä region in Central Finland. Myopia was defined based on questionnaire responses. The association between myopia and factors such as age group, sex, level of basic education, time spent on near work, TV watching and outdoor activity was analysed using univariate analyses and multiple logistic regression models.
Results
In the univariate analysis, the prevalence of myopia in 26‐year‐old Finns was 33.6%, while for 46‐year‐olds, it was 14.9%. In a multivariate logistic regression model, the factors most strongly associated with myopia were higher educational attainment, being born in 1957, and female sex. The lowest unadjusted prevalences for myopia were observed in 26‐ and 46‐year‐old men with a basic school education (8.6% and 7.9%), while the highest prevalences were found in 26‐ and 46‐year‐old women with a higher‐secondary school education (52.7% and 36.0%). The adjusted prevalence of myopia was higher in the younger age group across all sex and education categories. In the multivariate logistic regression model, higher education, a birth year of 1957 and female sex were the factors best predicting myopia.
Conclusion
Myopia prevalence among 25‐year‐olds was approximately double that of 46‐year‐olds in this study. This is likely associated with an increase in educational attainment, underscoring a role of education in the development of myopia within this population. The general improvement in living conditions has probably also had an impact on the change.