Prevalence of primary angle closure glaucoma in the last 20 Years: A meta-analysis and systematic review.

Author: Zhang N, Wang J, Chen B, Li Y, Jiang B.

Geographical coverage: Africa; Asia; Europe; South and North America; Oceania

Sector: Burden of disease

Sub-sector: Epidemiology; prevalence

Equity focus: Not reported

Study population: Adults with primary open angle glaucoma (POAG)

Review type: Epidemiology review

Quantitative synthesis method: Meta-analysis

Qualitative synthesis method: Not applicable

Background

Glaucoma is a major global health burden and a leading cause of irreversible blindness. Primary open angle glaucoma is projected to affect nearly 80 million adults by 2040. Its prevalence varies with age, sex and location. Earlier meta-analyses synthesised studies from 1960 to 2014. Numerous new studies justify an updated estimate.

Objectives 

To provide an up‑to‑date global prevalence of POAG (2000–2020) and explore associated risk factors.

Main findings

POAG remains a vision‑threatening disease affecting an estimated 68.56 million adults (aged ≥ 40 years) worldwide in 2020.

Fifty population‑based studies (198 256 participants) met the inclusion criteria. Overall pooled prevalence was 2.4 % (95 % confidence interval [CI] 2.0–2.8). Prevalence rose with age from 1.1 % (40–49 years) to 9.2 % (≥ 80 years) and was higher in men (relative risk 1.28). Geographical variation was evident: Africa (4.0 %) had the highest prevalence and Oceania (1.8 %) the lowest.

Methodology 

PubMed, Embase and Web of Science were searched for English‑language, population‑based cross‑sectional or cohort studies published between January 2000 and October 2020. Two reviewers independently screened, extracted data and assessed quality with the Quality in Prognosis Studies tool. Random‑effects meta‑analysis generated pooled estimates; heterogeneity was evaluated with the I² statistic and publication bias with contour‑enhanced funnel plots, p‑curve analysis and Egger’s test.

Applicability / external validity

Sparse data from South America, Oceania and North America may limit global representativeness; inclusion of broader open‑angle glaucoma definitions may slightly overestimate prevalence.

Geographic focus

Included studies were conducted in Africa, Asia, Europe, South and North America, and Oceania.

Summary of quality assessment
Medium confidence: the search was limited to English‑language studies and excluded‑study lists and risk‑stratified results were not provided.