Genetic effects on refraction and correlation with hemodynamic variables: a twin study

Area of Science:

• Ophthalmology
• Cardiovascular Science
• Genetics

Background:

• Spherical equivalent (SE) is a common refractive error.
• Previous research has not established a link between SE and cardiovascular morbidity.
• Understanding the interplay between ocular and cardiovascular health is crucial.

Purpose of the Study:

• To investigate the heritability of spherical equivalent (SE).
• To examine the association between SE and hemodynamic parameters, indicative of cardiovascular health.
• To determine if SE and cardiovascular parameters share common genetic or phenotypic factors.

Main Methods:

• A cohort of 132 Hungarian twins underwent autorefractokeratometry for SE measurements.
• Oscillometry was performed using a TensioMed Arteriograph to assess hemodynamic parameters.
• Heritability analyses and correlation studies were conducted, adjusting for age and sex.

Main Results:

• Heritability estimates for right and left SE were substantial (82.7% and 89.3%, respectively), indicating a major genetic component.
• Unshared environmental factors accounted for the remaining variation in SE.
• Weak, age-dependent correlations were observed between bilateral SE and parameters such as augmentation index, aortic pulse wave velocity, and blood pressure, but these associations were not strong.

Conclusions:

• The findings confirm the significant heritability of spherical equivalent.
• Spherical equivalent does not appear to be associated with altered hemodynamics or accelerated arterial aging.
• There is no evidence of phenotypic or genetic overlap between SE and the investigated hemodynamic parameters.