Prevalence of cataract type in relation to axial length in subjects with high myopia and emmetropia in an Indian population.
OBJECTIVE
To compare the prevalence of different types and densities of age-related cataract in subjects with high myopia and emmetropia in an Indian urban clinic-based population.


METHODS
Prospective, observational, clinic-based case-control study.


METHODS
An observational case-control study of 800 healthy eyes was undertaken at Iladevi Cataract & IOL Research Center, Ahmedabad, India. Subjects with high myopia (axial length [AXL], > or = 26.0 mm; n = 400 eyes) and those with emmetropia (AXL, 21.0 to 23.99 mm) were examined (n = 400 eyes). The type of cataract was categorized as: nuclear, cortical, or posterior subcapsular cataract (PSC). Nuclear density was measured based on the Emery and Little classification.


RESULTS
In all the age groups (40 years of age or more), nuclear cataract was encountered more often in subjects with high myopia (odds ratio, 3.8; 95% confidence interval, 2.9 to 5.2; P < .001); PSC and mixed cataracts were encountered frequently in subjects with emmetropia (P < .001). Prevalence of nuclear cataract was higher in subjects with high myopia with increasing AXL when compared with other types of cataract (P < .001). In all the age groups, the nuclear density was significantly higher than grade 3 in subjects with high myopia when compared with those with emmetropia (P < .001 in those younger than 70 years; P = .003 in those older than 70 years).


CONCLUSIONS
Nuclear cataract was associated strongly with high axial myopia. The density of the cataract was higher in the high myopia group. No association was observed between PSC or cortical cataract and high axial myopia.
Praveen
Mamidipudi R
MR
Iladevi Cataract & IOL Research Center, Raghudeep Eye Clinic, Ahmedabad, India.
Vasavada
Abhay R
AR
Jani
Urvi D
UD
Trivedi
Rupal H
RH
Choudhary
Prakash Kumar
PK
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001837:Body Weights and Measures; D016022:Case-Control Studies; D002386:Cataract / Q000145:classification / Q000453:epidemiology*; D005123:Eye / Q000473:pathology*; D005260:Female; D006801:Humans; D007194:India / Q000453:epidemiology; D007904:Lens Cortex, Crystalline / Q000473:pathology; D007907:Lens Nucleus, Crystalline / Q000473:pathology; D008297:Male; D008875:Middle Aged; D047728:Myopia, Degenerative / Q000453:epidemiology*; D015995:Prevalence; D011446:Prospective Studies; D014505:Urban Population / Q000706:statistics & numerical data