Myopic refractive shift caused by incident cataract: the Blue Mountains Eye Study.
OBJECTIVE
To assess the myopic shift in refraction caused by incident cataract in the Blue Mountains Eye Study (BMES) population.


METHODS
Five-year prospective follow-up of the BMES, initially performed in 1992. After 5 years, 2335 survivors (75.1%) of 3654 baseline BMES participants were re-examined. Refractive change was assessed by age, sex, incident cataract type and baseline refraction. Slit-lamp and retroillumination lens photographs were graded for presence of incident cataract and signs of previous cataract surgery. Objective and subjective refractions were performed.


RESULTS
In a multivariate model, age (p < 0.0001), incident nuclear cataract (p < 0.0003), hyperopia (p < 0.0009), incident posterior subcapsular cataract (p < 0.0027) and incident cortical cataract (p < 0.025) were factors associated with a relatively modest myopic refractive shift (0.34 diopters). Baseline myopia and gender were not associated with refractive change over the follow-up period. A myopic shift in refraction occurred most frequently in older (> or = 70 years) than younger (< 70 years) participants.


CONCLUSIONS
Older age, baseline hyperopia and all types of incident cataract were principal factors found associated with myopic refractive shift over 5 years in an older population.
Panchapakesan
Jai
J
Department of Ophthalmology, Centre for Vision Research, University of Sydney, Westmead Hospital, NSW, Australia.
Rochtchina
Elena
E
Mitchell
Paul
P
D000368:Aged; D000369:Aged, 80 and over; D002386:Cataract / Q000145:classification / Q000150:complications* / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000453:epidemiology / Q000209:etiology*; D009517:New South Wales; D011446:Prospective Studies; D012029:Refraction, Ocular