Risk of acute angle-closure and changes in intraocular pressure after pupillary dilation in patients with diabetes.

BACKGROUND: To evaluate the risk of AAC and intraocular pressure (IOP) changes in diabetic patients after pupil dilation. METHODS: This cross-sectional study enrolled 2,287 diabetic patients among community residents in Guangzhou, China. All participants underwent routine pupil dilation unless they had a history of glaucoma. IOP was measured using a non-contact tonometer before and one hour after pupil dilation with tropicamide 0.5% and phenylephrine 0.5% eye drop. The proportion of AAC and changes in IOP after pupil dilation were evaluated. RESULTS: Only one of the 2,287 participants (0.04%) with diabetes developed post-dilation AAC. The mean pre and post-dilation IOP in the right was 16.1 ± 2.7 and 16.5 ± 2.8 mmHg (P < 0.001); mean pre and post-dilation IOP in the left was 16.5 ± 2.7 and 16.8 ± 2.8 mmHg (P < 0.001). Sixty-one participants (2.7%) showed an increase in IOP ≥ 5 mmHg and 25 participants (1.1%) showed a post-dilation IOP > 25 mmHg, including 11 participants (0.5%) who had both an increase in IOP ≥ 5 mmHg and post-dilation IOP > 25 mmHg. Lower pre-dilation IOP (OR = 0.827; 95% CI, 0.742-0.922; P = 0.001) and shallower anterior chamber depth (ACD) (OR = 0.226; 95% CI, 0.088-0.585; P = 0.002) were significant risk factors for an increase in IOP ≥ 5 mmHg in multivariate logistic regression analysis. CONCLUSIONS: The risk of developing AAC after pupil dilation in diabetic patients was very low. Lower pre-dilation IOP and shallower ACD are risk factors for increased post-dilation IOP.