Abstract
Purpose: :
To quantify and characterize the prevalence of pseudoexfoliation syndrome in patients of Ethiopian descent. Pseudoexfoliation syndrome (PEX) is associated with open-angle glaucoma and has long been known to have a high prevalence in certain ethnic groups, such as Scandinavians. Our clinic in Washington D.C. sees a large population of Ethiopians and it has been noted anecdotally that PEX appears frequently in these patients, but no previous population-based studies have been done.
Methods: :
In a retrospective study, 172 Ethiopian patients seen in clinic during the calendar year 2010 were identified using the electronic medical record. The charts were reviewed to determine the prevalence of PEX and its associations with age, gender, cup-disc ratio, intraocular pressure (IOP), open-angle glaucoma diagnosis, optical coherence tomography (OCT) data, and treatments employed.
Results: :
The mean age of the 172 patients was 56.0 ± 13.4 years (range 22-81 years). There were 16 patients in which PEX was noted (9.30%); 11/16 of these had bilateral involvement (68.8%). The prevalence of PEX was significantly associated with increasing age; the youngest patient diagnosed was 54, and of those patients age 60 or higher, the prevalence increased to 18.75%. PEX was strongly associated with glaucoma, with 8/16 PEX patients vs. 11/156 non-PEX patients carrying a glaucoma diagnosis (p <0.000001). An additional 5/16 PEX patients were glaucoma suspects. There was no difference in the rates of PEX between males (7/74 (9.46%)) and females (9/98 (9.18%)) (p =0.95). Additionally, there was a significant increase in C/D ratio in eyes with PEX (0.596 ± 0.258) compared to those without (0.401 ± 0.172392) (p <0.0001). There was no significant difference in mean IOP (13.0 ± 2.83 vs. 13.56 ± 2.67) (p =0.43); however, the PEX group included 4 patients post-trabeculectomy, as well as average of 2.14 IOP lowering medications per glaucoma diagnosis. Patients with PEX showed significantly more OCT nerve fiber layer thinning (68.11µ ± 18.66) than patients without (87.66µ ± 21.44) (p <0.05)
Conclusions: :
The prevalence of PEX among Ethiopian patients is high and is associated with significant risk of secondary glaucoma. Further study is indicated to elucidate possible genetic linkages between the Ethiopian population and other high-risk groups; e.g. to see if the high-risk haplotype of LOXL1 associated with PEX in Scandinavians is also present in Ethiopians, and to investigate if other risk-conferring genes may be located.
Keywords: clinical (human) or epidemiologic studies: prevalence/incidence