Central Corneal Thickness Variances Among Different Asian Ethnicities in Glaucoma and Nonglaucoma Patients

Abstract

Objective: To compare the central corneal thickness (CCT) between different ethnicities and particularly Asian subethnic groups that may contribute to the different glaucoma diagnoses using the optical low-coherence reflectometry technique. Methods: A retrospective study of 6 years including 1512 eyes of 929 patients of the Beckman vision center, University of California, San Francisco from 2011 to 2017 had their biometric parameters, including CCT, measured with the Lenstar. Patients were categorized into African Americans, Caucasians, Hispanics, Pacific Islanders, and Asians. Asians were further subcategorized into Chinese, Vietnamese, Koreans, Filipinos, and Japanese. Results: Among 1356 patients who had their CCT measured by Lenstar from 2011 to 2017, 1512 eyes of 929 patients were included. The study population included 462 Caucasians (52.96%), 60 African Americans (6.46%), 92 Hispanics (9.9%), 32 Pacific Islanders (3.44%), 130 Chinese (13.99%), 52 Filipinos (5.6%), 37 Vietnamese (3.98%), 34 Koreans (3.66%), and 30 Japanese (3.23%). African Americans had the thinnest CCT with a mean of 518.62±40.3 followed by Asians with a mean of 539.29±34.1. Among the Asian study sample, the Chinese had the thinnest CCT with a mean of 537.66±32.5. CCT was adjusted for age, sex, glaucoma diagnosis, diabetes status, and prostaglandin analogs use for >12 months. Conclusions: Optical low-coherence reflectometry is a widely used technology, which can measure CCT. Our study confirms that African Americans have the thinnest corneas followed by Asians. In the latter group, relatively thin CCT may partly explain their high rates of normal-tension glaucoma.

A multiethnic genome-wide analysis of 44,039 individuals identifies 41 new loci associated with central corneal thickness

“…For this study, our GERA sample consisted of 18,129 individuals from four ethnic groups (79.9% non-Hispanic white, 7.5% Hispanic/Latino, 8.4% East Asian, and 4.2% African American) with a measured CCT (Table 1). In our GERA sample, African Americans had thinner CCTs on average than other groups, consistent with previous reports [5][6][7] .…”

“…Reduced CCT is a feature of keratoconus 1 , and, by some accounts, is associated with an increased risk of primary open-angle glaucoma (POAG) [2][3][4] . Epidemiological observational studies have implicated demographic and clinical risk factors that influence CCT, including, sex, glaucoma diagnosis, and ethnicity [5][6][7][8] . Individuals of African ancestry have thinner CCT but also increased POAG risk, and have worse visual field damage and disease progression compared to other populations [5][6][7]9,10 .…”

“…Epidemiological observational studies have implicated demographic and clinical risk factors that influence CCT, including, sex, glaucoma diagnosis, and ethnicity [5][6][7][8] . Individuals of African ancestry have thinner CCT but also increased POAG risk, and have worse visual field damage and disease progression compared to other populations [5][6][7]9,10 . It is, however, not clear whether the observed variation in CCT confounds, or directly contributes to the greater glaucoma burden in African ancestry populations.…”

Incidence and Risk Factors of Corneal Endothelial Failure after Phacoemulsification in Patients with Fuchs Endothelial Corneal Dystrophy: A 13-Year Retrospective Cohort

“… 19 It should be noted that pachymetry values can vary with gender and age, and differ between ethnic groups as well as measurement techniques. 20 , 21 Therefore, to apply this extended criteria in different clinical settings should be considered with caution. Although, all patients in our cohort had pre-operative CCT values that complied with the guideline, we found that 9 (9.57%) patients eventually developed CEF within the 10 years of follow-up period, corresponding to the incidence rate of 26 per 1000 person years.…”

Reference values of the central corneal thickness with different refractive errors for the adult Egyptian population

“…It is reported to be thinner in elders and African-Americans than in whites [6,7]. Some studies showed that men had thicker corneas [8,9]. So, this study aimed to give reference values of the central corneal thickness with different refractive errors for the adult Egyptian population.…”