Determinants and risk factors for central corneal thickness in Japanese persons: the Funagata Study.

Abstract

To examine the association between glucose metabolism and central corneal thickness (CCT) in Japanese adults.
A sub-sample of 322 Japanese adults participating in the Funagata Study was included in this analysis. CCT was measured using a specular microscope. Glucose metabolism was examined using 75-g oral glucose tolerance test. Mean differences in CCT (μm) and 95% confidence intervals were estimated with univariate, age-sex-adjusted and multivariate models using multiple linear regression.
The mean (± standard deviation) age of the study sample was 63.7 ± 11.4 years and 44% were men. The mean fasting plasma glucose (FPG), 2-hour post-load plasma glucose (2hPG) and haemoglobin A1c (HbA1c) concentrations were 96.8 ± 12.6mg/dl, 123.6 ± 41.2mg/dl and 5.3 ± 0.4%, respectively. CCT was normally distributed in the study sample, and the mean CCT was 544.7 ± 34.6μm. After multivariate adjustment, characteristics associated with increased CCT were 2hPG and HbA1c concentrations, impaired glucose tolerance, diabetes, body weight or body mass index and current smoking.
Impaired glucose tolerance, diabetes, obesity and current smoking are associated with increased CCT. Additional studies are required to examine whether interventions to affect these characteristics may reduce CCT.