Anisometropia is independently associated with both spherical and cylindrical ametropia.

Title
Anisometropia is independently associated with both spherical and cylindrical ametropia.
Source
Investigative Ophthalmology & Visual Science. 46(11):4024-31, 2005 Nov.

PURPOSE:

To explore the associations between anisometropia and spherical ametropia, astigmatism, age, and sex.

METHOD:

Associations between the prevalence and magnitude of anisometropia with age, sex, spherical power, and cylindrical power, were assessed in a group of 90,884 subjects attending optometry practices in the United Kingdom.

RESULTS:

Logistic regression analyses that included all subjects or just those aged 20 to 40 years showed that spherical ametropia and astigmatism were independently associated with anisometropia. Anisometropia was relatively stable between the ages of 20 and 40 years, but then became more common with age, in myopes from the age of 40 years onward and in hyperopes from the age of 70 years onward. Sex was not associated with anisometropia to a clinically significant extent.

CONCLUSIONS:

This is the first study to show an independent association between anisometropia and both spherical ametropia and astigmatism. The results also suggest that the previously noted increased prevalence of anisometropia with age occurs later in hyperopes than in myopes, once other covariates have been controlled for.

Anisometropia : A condition in which the refractive power of one eye differs from that of the other.