Abstract
Purpose :
To report the progression of primary angle closure disease (PACD), in a South Indian population, after 6 years of follow-up
Methods :
At the baseline Chennai Glaucoma Study, all participants with PACD were advised laser peripheral iridotomy (LPI). After the procedure, they were reviewed for the assessment of patency of LPI, angle status and intraocular pressure (IOP). Six years later they were followed up in the Chennai Eye Disease Incidence Study. We used International Society of Geographical and Epidemiologic Ophthalmology classification for the definition of PACD and studied rates of progression. Progression to primary angle closure (PAC) was defined as the development of peripheral anterior synechiae (PAS) and/or elevated IOP; disc or field changes to diagnose progression to primary angle closure glaucoma (PACG). For the analysis, subjects who had bilateral cataract surgery in the interim were excluded, if one eye was operated the contralateral phakic eye was included. Uni and multivariate analysis for risk factors (age, gender, IOP, ocular biometry and vertical cup disc ratio) was performed.
Results :
At the baseline, there were 727 subjects with PACD, of which 391 subjects were examined for the follow up study. Of these 317 subjects (Rural: 134 (42.2%), Urban: 183 (57.8%)) were eligible for the current study. There were 117(36.9%) male and 200(63.1%) female subjects. At the baseline, 234(73.8%) subjects were diagnosed as primary angle closure suspect (PACS), 55(17.4%) PAC and 28(8.8%) PACG. Following LPI a transient rise in IOP occurred in 42 (13.5%) subjects who were treated with anti-glaucoma medications. Seven (2.2%) subjects with PACD refused LPI. At the follow-up, 32 subjects (10.09%, 95% CI: 6.77 – 13.40) had progression; of these, 29/234 (12.39%, 95% CI: 8.16 – 16.61) progressed from PACS to PAC and 3/55 (5.45%, 95% CI: - 0.54 – 11.44) from PAC to PACG. None progressed from PACS to PACG. On logistic regression, baseline IOP (tertiles: <15mmHg, 15 to 18 mmHg, >18mmHg) of 15 to 18mmHg (OR: 4.28, 95% CI 1.30 – 14.09, p=0.02) and more than 18mmHg (OR: 6.65, 95% CI: 2.11 – 20.94, p=0.001) was found to be a significant risk factor for disease progression.
Conclusions :
In the PACD spectrum despite LPI one tenth of the patients can progress to the next stage over six years. Higher intraocular pressure at baseline was a significant risk factor.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.