Open-angle glaucoma and blood groups. The Barbados Eye Study
M. C. Leske, B. B. Nemesure, Q. He, N. Mendell and A. Polednak
University Medical Center at Stony Brook, NY, USA.
OBJECTIVE: To evaluate the association of open-angle glaucoma (OAG) with
ABO, Rh and Duffy blood groups in the population-based Barbados Eye Study.
DESIGN: Case-control study. SETTING AND PARTICIPANTS: A subset of black
Barbados Eye Study participants, which included 199 OAG cases and 1063
controls. DATA COLLECTION: ABO, Rh and Duffy blood groups were determined
as part of a comprehensive study visit, which included assessment for OAG
through perimetry, fundus photography, and ophthalmologic examination.
OUTCOME MEASURES: Comparison of blood groups between OAG cases and nonOAG
controls, expressed as odds ratio and 95% confidence intervals. RESULTS:
Associations were found with the Duffy Fya+ group, which is more frequent
in white than black populations. In Mantel-Haenszel analyses, OAG was
positively associated with Duffy Fya+ in men (odds ratio, 2.67; confidence
interval, 1.52 to 4.69) and in persons with intraocular pressure more than
21 mm Hg (odds ratio, 3.32; confidence interval, 1.49 to 7.38). Logistic
regression analyses confirmed these findings (interaction of Duffy Fya+ and
male gender, P = .01; interaction of Duffy Fya+ and intraocular pressure, P
= .04). No associations between OAG and the ABO or Rh blood groups were
seen. CONCLUSIONS: The associations with Duffy Fya+, which had not been
reported previously in a black population, support the involvement of
genetic factors in OAG. However, the lack of association between OAG and
blood group markers of African ancestry is inconsistent with a genetic
explanation for the differences in OAG prevalence between blacks and
whites. Our findings suggest gene-environment interactions in OAG, to be
explored by further studies of OAG and Fy markers by racial group and
gender.
