Following prevalence of myopia in a large Swiss military cohort over the last decade: where is the European "myopia boom"?

Purpose Myopia prevalence is increasing globally, with the highest rates found in Asia. Data from European countries is scarce. We aimed to investigate whether the prevalence of myopia is rising in our meridians. Methods Data from male military conscripts for the recruitment period of 2008–2017 were retrospectively analyzed. Year of recruitment, conscripts’ birth year, visual acuity, refractive status (spherical equivalent), and spectacle wear (yes/no) were available. Results The dataset contained data of a total of 355,657 male conscripts, who had been recruited in the years 2008 to 2017. The mean number of conscripts per year was 35,566 (MD = 35,440, SD = 1249), reaching a minimum number of 33,998 conscripts in 2017 and a maximum of 37,594 in 2011. Mean age at recruitment was 19.7 years (MD = 19.0 years, SD = 1.1 years). Overall, the number of conscripts wearing spectacles remained stable over the observation time; on average 29.6% (n = 10,540; MD = 10,472; SD = 492) of conscripts wore glasses at recruitment. Of 21.8% (n = 77,698) of conscripts, data on the refractive status was available: The mean spherical equivalent for both right and left eyes was -2.3D (MD = -2 D, SD = 2.4 D). No decrease in mean spherical equivalent per recruitment year was noted over the observation period. Estimated myopia prevalence reached an average of 27.5% (SD = 0.8%) and did not increase during the observation period. Conclusion In summary, no change in spherical equivalent refractive errors of male Swiss army conscripts was found for the years 2008–2017. Equally, the percentage of spectacle wearers (MN = 29.6%) and estimated myopia prevalence (MN = 27.5%) did not significantly increase during the observation time.