Abstract
Purpose:
In Japan, there have been few studies which have analyzed the prescription of contact lenses on a large scale of Japanese subjects by sex and age group, detailing the year of prescription, longitudinally and in detail. Therefore, we made an 8 year-large scale epidemiological study analyzing approximately 930,000 eyes of Japanese contact lens users and the prescription of approximately 5,840,000 boxes of various contact lenses by sex, age groups and the year of the prescription.
Methods:
The subjects of this research is the 930,742 eyes of men and women aged 7-96 who had a medical examination for a prescription of contact lenses at Okada Eye Clinic in Yokohama, Japan; and 5,843,617 boxes of contact lenses which were prescribed between January 2005 and December 2012.
Results:
The number of the contact lenses prescribed was 5,843,617 boxes in total: 2,156,239 boxes prescribed to men; 3,687,378 boxes prescribed to women. The type of the contact lenses which was prescribed the most was the 1-day contact lenses, followed by the 2-week contact lenses. Also, by analyzing the adjustment mean value of the number of various contact lenses prescribed per eye longitudinally and comparing the trend by sex and age group, 1-day and 1-month contact lenses significantly increased in both sexes (p<0.0001). On the other hand, prescription of the 2-week contact lenses significantly decreased in both sexes, but the change in refraction was small (p<0.0001). 1-day and 1-month contact lens prescription had a tendency to increase, and by analysis of sex and age group, 1-month contact lenses significantly increased in almost all age groups. Also, 1-day contact lens prescriptions significantly increased in men in the age group of 30-49, and in both sexes in the age group of 25-49.
Conclusions:
Following 8 years prospective research and longitudinal analysis by sex and age group of various contact lenses in Japan, both 1-day and 1-month contact lens prescription significantly increased in both sexes. Furthermore, prescription of 1-day contact lenses increased in the middle age groups of the 30s and the 40s, and 1-month contact lens prescriptions increased in nearly all age groups.
Keywords: 477 contact lens