Abstract
Purpose: :
To investigate the prevalence of pseudoexfoliation (PEX) in subjects of three different areas in China.
Methods: :
All citizens, aged ≥50 yrs, of Shangliu village, Shenyang city (latitude 41ºN); Miaolin village, Sanya city (latitude 18ºN) and Liujiapn village, Taiyuen city (latitude 38ºN) were offered eye examinations. Some 274 (50.5% of eligible) in Shenyang, 558 (79.6% of eligible) in Sanya and 690 (91.3% of eligible) in Taiyuen were examined. All subjects from Shenyang and Taiyuen were Han Chinese. In Sanya, 34.4% of subjects were Han Chinese, 65.6% were Lie Chinese.Diagnosis of PEX was made by slitlamp examination both in dilated and un-dilated pupil as central disc and peripheral band on the anterior lens capsule.
Results: :
After excluding eyes with corneal opacity, aphakia and pseudophakia,, there were 233 subjects (59.9±8.2 years old) in Shenyang, 533 (61.2±10.8 years old) in Sanya and 689 (60.8±8.9 years old) in Taiyuen. The number of cases with PEX were one (0.4%)(Male 61 years old) in Shenyang, 13 (2.4%)(Male one 74 years old, Female 12 69.5±11.7 years old) in Sanya and none in Taiyuen. Of all three locations, PEX was found in just two cases in Han Chinese (0.2%). In Sanya, the prevalence of PEX was significantly higher in Lie Chinese (12 cases, 3.4%) than in Han Chinese (1 case, 0.5%) (p<0.05). Of all 14 PEX cases, there were 9 cases of unilateral PEX and 5 cases of bilateral PEX. There were no cases of intraocular pressure of over 21mmHg and only one case had glaucoma-like optic disc change.
Conclusions: :
Prevalence of PEX is very low in Han Chinese in three climatically different places. This may suggest that genetic factors are more important than environmental factors in development of PEX.
Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • clinical (human) or epidemiologic studies: natural history • clinical (human) or epidemiologic studies: outcomes/complications