Glaucoma prevalence in the Nordic countries. Estimates based on glaucoma drug consumption.

Glaucoma prevalences in the 5 Nordic countries are estimated on basis of a) wholesale of glaucoma medicaments (Denmark, Iceland, Norway, and Sweden) and b) registered glaucoma patients receiving free medication (Finland). Prevalences are compared nationally and internationally. The estimated glaucoma prevalence is highest in Norway (2.19% related to the population greater than 40 years), lowest in Denmark (0.76% in the same age group). The prevalence in Iceland, Finland, and Sweden are 2.0, 1.94, and 1.55%, respectively. We suggest that the relatively large differences in glaucoma prevalence between the countries may be explained by geographical differences in occurrence of capsular glaucoma. The sources of error concerning prevalence estimates based on glaucoma drug consumption are discussed. Pre-supposing a balance numerically between undetected glaucoma cases and patients receiving glaucoma medication without really having glaucoma, the glaucoma drug sales statistics may be taken as fair indicators of glaucoma prevalence.