The Prevalence of Diabetic Retinopathy in Indigenous Versus Non-Indigenous Populations in Canada: A Systematic Review and Meta-Analysis

Theme: Global and public health ophthalmology
What: Global and public health ophthalmology
Part of: CAPHGO: Global Eye Care - Challenges beyond VISION 2020 with 2030 in Sight / CAPHGO: Soins oculaires mondiaux Défis au-delà de VISION 2020 avec 2030 en ligne de mire
When: 6/2/2024, 02:00 PM - 03:30 PM
Where: Room | Salle 714 B

Abstract

Purpose: Indigenous Canadians disproportionately suffer from higher rates of diabetes and diabetes-related complications compared to non-Indigenous Canadians. Previous studies evaluating the rates of diabetic retinopathy in Indigenous and non-Indigenous Canadians have demonstrated conflicting results. The purpose of this investigation is to compare the prevalence of diabetic retinopathy (DR) in adult Indigenous Canadians compared to non-Indigenous Canadian patients with diabetes.

Study Design: Systematic review and meta-analysis.

Methods: This systematic review was registered, and all analyses were pre-specified on PROSPERO (CRD42023464825). Ovid MEDLINE, EMBASE, and Web of Science Databases were searched from inception until July 30^th, 2023, for studies evaluating the prevalence of DR in Indigenous or non-Indigenous Canadian diabetics. Two independent reviewers in duplicate reviewed all titles, abstracts, and full texts, performed data extraction, and conducted risk of bias assessments according to the Joanna Briggs Institute Appraisal Checklist for Prevalence Studies. 

The prevalence between groups for the following outcomes were compared: a) any stage of DR, b) diabetic macular edema (DME), c) proliferative diabetic retinopathy (PDR), d) vision-threatening diabetic retinopathy (VTDR), e) PDR complications. 

Meta-analyses and multivariable meta-regressions were performed using Freeman Tukey double arcsine transformation and random-effects modelling. Analyses were performed in R (version 4.3.1).

Results: Sixteen studies comprising 17,989 individuals were included. The studies reporting prevalence rates in Indigenous individuals included younger patients (50.9 years vs. 57.7 years; p=0.009), had a higher proportion of females (0.63 vs. 0.53; p=0.007), and had lower appraisal scores (79% vs 93%; p=0.025).

There was no difference between groups in the prevalence of DR (0.33 vs. 0.30; p=0.788), prevalence of DME (0.04 vs. 0.04; p = 0.591), or prevalence of PDR (0.02 vs 0.03; p=0.314). The rate of VTDR was higher in the Indigenous group (0.14 vs 0.06; p=0.021). No study reported rates of PDR complications.

Post-hoc analyses evaluating the prevalence of DR between groups remained non-significant after adjusting for age (p=0.272), and appraisal score (p=0.087).

Conclusion:

There was no difference in the prevalence of DR, PDR, or DME in Indigenous and non-Indigenous groups. The rate of VTDR was higher in the Indigenous group suggesting that Indigenous patients have more severe disease. Studies of indigenous individuals included younger patients and had lower methodologic quality scores thus potentially underestimating the disease burden in the indigenous population.

Building on current efforts to deliver high-quality, culturally appropriate care targeted at reducing risk factors and removing barriers to care in Indigenous communities must remain a public health priority.

 

Presenter(s)

Presenting Author: Keean Nanji

Additional Author(s):

Felicia Tai, McMaster University

Michele Zaman, Queen's University

Jane Jomy, Univeristy of Toronto

David Mikhail, University of Toronto

Mark Phillips, McMaster University, Department of Health Research Methods, Evidence and Impact, 1280 Main Street West, Hamilton, Ontario, Canada

Dena Zeraatkar, McMaster University, Department of Health Research Methods, Evidence and Impact, 1280 Main Street West, Hamilton, Ontario, Canada

Tien Wong, Singapore Eye Research Institute, Singapore National Eye Centre, Singapore

Sobha Sivaprasad, NIHR Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK

Charles Wykoff, Retina Consultants of Texas, Houston, Texas, Blanton Eye Institute, Houston Methodist Hospital, Houston, Texas, USA

Varun Chaudhary, McMaster University, Department of Health Research Methods, Evidence and Impact, 1280 Main Street West, Hamilton, Ontario, Canada

---