Factors Associated with Long-term Intraocular Pressure Fluctuation in Primary Angle Closure Disease: The CUHK PACG Longitudinal (CUPAL) Study

Carol Y. Cheung, Sophia Ling Li, Noel Chan, Mandy Oi Man Wong, Poemen Pui Man Chan, Isabel Lai, Nafees Baig, Shaoying Tan, Xiaofei Man, Fangyao Tang, Yu Meng Wang, Clement C. Tham

Research output: Journal article publicationJournal articleAcademic researchpeer-review

4 Citations (Scopus)


Purpose: To determine the demographic, ocular, and systemic factors associated with long-term intraocular pressure (IOP) fluctuation in primary angle closure disease (PACD). Methods: This prospective cohort study included 422 PACD eyes from 269 Chinese patients, including 274 primary angle closure glaucoma (PACG) eyes and 152 primary angle closure/primary angle closure suspect (PAC/PACS) eyes. Long-term IOP fluctuation defined as the SD of all IOP measurements over 2 years (at least 5 measurements in total). Chinese patients with PACD were recruited and followed up 3 monthly. Eyes with IOP-lowering surgery or lens extraction performed within the 2-year study period were excluded. Patient demographics, received treatments, ocular biometry, retinal nerve fiber layer thickness, and systemic factors (eg, hypertension, smoking) were evaluated. Generalized estimating equations adjusting for inter-eye correlation were used to determine the associations. Results: Eyes with PACG had significantly higher IOP fluctuation than PAC/PACS (2.4±1.2 versus 2.1±0.9 mm Hg; P=0.04). In the multivariate analysis with PACG eyes, higher baseline IOP (P<0.001), greater number of IOP-lowering medications (P<0.001), previous trabeculectomy (P=0.002), and current smoking (P=0.03) were significantly associated with larger IOP fluctuation, whereas diabetes mellitus was associated with lower IOP fluctuation (P=0.03). Among PAC/PACS eyes, younger age group (P<0.001), male sex (P=0.002), and higher baseline IOP (P<0.001) were significantly associated with larger IOP fluctuation. Conclusions: PACG eyes have greater IOP fluctuation than PAC/PACS eyes. Certain demographic, ocular, and systemic factors are associated with IOP fluctuation in PACD eyes.

Original languageEnglish
Pages (from-to)703-710
Number of pages8
JournalJournal of Glaucoma
Issue number8
Publication statusPublished - 1 Aug 2018
Externally publishedYes


  • affecting factors
  • IOP fluctuation
  • Key Words: long-term IOP
  • PACD

ASJC Scopus subject areas

  • Ophthalmology

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