Phenotypic features of Chinese family members with primary angle closure

Objective: To describe ocular phenotypic features in Chinese families with primary angle closure (PAC). Design: Prospective cohort study. Participants: 428 individuals of 103 eligible families. Methods: Probands identified in clinic and their relatives were examined. Measurements included intraocular pressure, anterior chamber depth, lens thickness, axial length, and gonioscopic features related to the anterior chamber angle. Electroretinogram (ERG) testing for dark and light adaptation on both eyes of each individual examined was also obtained. Results: There were 144 PAC affected patients (33.7%), 60 suspects (14%), and 224 unaffected individuals (52.3%). There were more than 2 affected members in 51 families (49.5%). Compared with unaffected individuals, affected individuals were more likely to be female, have shallower peripheral and central anterior chamber depths, narrower angles, thicker lenses, and shorter axial lengths (p < 0.001). Affected patients and suspects had similar axial lengths (p > 0.05). Compared with unaffected individuals, affected and suspect individuals showed ERG adaptation abnormalities (p < 0.05). Of 45 unaffected individuals with mean axial length r 22.00 mm (10.51%), 20 individuals (4.67%) showed ERG adaptation abnormalities similar to affected patients and suspects (p > 0.05). Conclusions: Patients with PAC were significantly more likely to be female, have shorter axial length, and have thicker lenses compared with unaffected individuals. PAC suspects showed similar axial lengths to affected individuals. ERG abnormalities mainly occurred in affected patients and suspects, but also occurred in unaffected individuals with short axial length.