An observational study in Primary Angle-Closure Glaucoma, sponsored by Zhongshan Ophthalmic Center, Sun Yat-sen University. Not yet recruiting. Open to participants aged 70 Years to 100 Years. Per ClinicalTrials.gov, last updated 2024-03-28.
Sponsored by Zhongshan Ophthalmic Center, Sun Yat-sen University · Observational
Primary angle-closure glaucoma (PACG) is one of the major causes of blindness affecting more than 20 million patients worldwide. The goals of this observational cohort study are to investigate the 20-year incidence of PACG in Chinese population aged 50 years and to develop prediction models for the long-term risk of progression from primary angle-closure suspect (PACS) to PACG.
Primary angle-closure glaucoma (PACG) is potentially a devastating disease, responsible for half of glaucoma-related blindness worldwide, especially in East Asia. Primary angle-closure suspect (PACS), which is characterized by appositional angle closure, is the earliest stage of primary angle closure diseases and can finally progress to PACG. Thus, identifying PACS eyes at risk of angle closure is crucial for its management. However, the natural history of progression from PACS to PACG and its prediction models are still limited in long-term longitudinal studies. Meanwhile, visual impairment poses a significant global public health burden along with the accelerating trend of aging, it is imperative to further evaluate the visual impairment among the elderly population.
The Liwan Eye Study was a population-based study initiated in 2003. The decision to select Liwan District for the survey was taken because of its stable, older population and a socioeconomic profile representative of Guangzhou as a whole. At baseline, 1405 eligible subjects aged 50 years and older completed a comprehensive eye examination and a questionnaire interview regarding education, income, hypertension and diabetes mellitus. To improve the monitoring of PACS and prevent vision loss associated with PACG, the purposes of this observational cohort study are to investigate the 20-year incidence of PACG in Chinese population aged over 50 years, develop prediction models that include eye characteristics, demographic features, ocular imaging characteristics, and genetic factors for the long-term risk of progression from PACS to PACG. Moreover, we aim to investigate the 20-year change in visual impairment and associated factors.
91 studies on the registry are indexed under Glaucoma, Angle-Closure; 17 are open to participants now.
This study's planned enrollment of 600 is above the median of 225 across 32 observational studies indexed under Glaucoma, Angle-Closure.
Browse Glaucoma, Angle-Closure studies →Zhongshan Ophthalmic Center, Sun Yat-sen University is the lead sponsor of 164 studies on the registry; 80 are open to participants now.
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All participants who will be follow-up in this study are from the Liwan Eye Study. At baseline, study subjects were enrolled in Liwan District, Guangzhou. (Liwan District is 1 of 10 administrative districts in Guangzhou, with a population of 514,600.) The decision to select this district for the survey was taken because of its stable, older population and a socioeconomic profile representative of Guangzhou as a whole. Individuals aged 50 years or more who had been resident in the selected study districts for more than 6 months were considered eligible during the enumeration. A total of 1405 eligible subjects were identified from the register.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Primary angle-closure suspect (PACS), which is characterized by appositional angle closure, is the earliest stage of primary angle closure diseases and can finally progress to primary angle-closure glaucoma (PACG).
The 20-year incidence of primary angle-closure glaucoma (PACG) in Chinese population aged over 50 years
The presence of PACG is determined by visual acuity, intraocular pressure, anterior segment optical coherence tomography (AS-OCT). The incidence of PACG is defined as the number of new cases of PACG divided by the number of individuals without PACG at baseline.
Time frame: 20-year
The development of prediction models for the long-term risk of progression from primary angle-closure suspect (PACS) to primary angle-closure glaucoma (PACG)
Prediction model performance was assessed by discrimination and calibration.Discrimination was evaluated using the ROC curve and area under the curve (AUC) or C-statistics. Calibration was visualized through calibration plots and evaluated using the Hosmer-Lemeshow goodness-of-fit test (HL test).
Time frame: 5-year, 10-year, 20-year
The 20-year incidence of visual impairment in Chinese population aged over 50 years
Visual acuity (VA) will be measured using the Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR illiterate E VA chart. Visual impairment is defined as VA \<20/60 \& ≥20/400, and blindness is defined as VA\<20/400 in the better-seeing eye.
Time frame: 20-year
No study locations are listed for this record.
Plan to share: Yes — Available on request. The datasets generated from the current study will be available upon request from Dr Wei Wang (wangwei@gzzoc.com) after the study is completed.
Supporting information: Study protocol
Access criteria: For access to the data, please contact the principal investigator after the study is completed.
No publications or documents are linked to this record.
Start is estimated for Mar 2024; primary completion for Sep 2024, 6 months later.
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This study is not yet recruiting, as verified in Mar 2024. You cannot join it, but the record below documents what was studied.
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Zhongshan Ophthalmic Center, Sun Yat-sen University →