Asymmetric refraction in an older population: the Blue Mountains Eye Study.
OBJECTIVE
To describe prevalence and associations of asymmetric refraction in an older population.


METHODS
All participants in the Blue Mountains Eye Study had comprehensive eye examinations, including refraction. Spherical equivalent (SEq = sum sphere +.5 cylinder), in diopters, defined refractive error. Refractive asymmetry was assessed in phakic participants; anisometropia was defined as > or =1.0 diopters SEq difference between eyes.


RESULTS
Anisometropia was present in 14.7% of participants. Mean refractive asymmetry (in diopters) in persons aged <60 years was 0.43; 60 to 69 years, 0.51; 70 to 79 years, 0.72; and 80+ years, 0.88. Prevalence and severity of anisometropia increased with age (P <.001), increasing ametropia or astigmatism. Associations included older age, cataract, and increasing ametropia. Myopic participants >-3.0 diopters had the highest anisometropia prevalence.


CONCLUSIONS
Refractive asymmetry was associated with age, increasing ametropia, and cataract.
Guzowski
Magdalena
M
University of Sydney Department of Ophthalmology, Centre for Vision Research, Westmead Hospital and the Westmead Millennium and Save Sight Institutes, Westmead NSW, Australia.
Fraser-Bell
Samantha
S
Rochtchina
Elena
E
Wang
Jie Jin
JJ
Mitchell
Paul
P
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D015858:Anisometropia / Q000453:epidemiology* / Q000209:etiology; D002386:Cataract / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009517:New South Wales / Q000453:epidemiology; D015995:Prevalence; D012029:Refraction, Ocular