Undetected glaucoma is highly prevalent in diverse communities across the globe and may be more common in Africa and Asia, recent research published online in Ophthalmology suggests.

The investigation, a systemic review and analysis of population-based studies, found that, globally, more than half of all glaucoma cases were previously undetected in each geographical region.

Of note: in 2020, about 44 million POAG cases were undetected, of which approximately 77% came from residents of Africa and Asia.

“We predicts that 67 million people with POAG will likely be undetected by 2040 if the current detection rate remains unchanged and no effective public health policy changes are implemented,” the authors wrote in their paper.

Regionally, Africa and Asia had higher odds of undetected glaucoma compared to Europe. Additionally, countries with low human development index rates (HDI, less than 0.55) had higher proportions of undetected manifest glaucoma compared to countries with medium to very high HDI (0.55 or more).

Although the odds of undetected manifest glaucoma were lower in countries with medium to very high socioeconomic development, more than 70% of cases remain undetected, on average. The reasons behind undetected glaucoma cases are not simply a matter of country income and development, which are factors associated with more robust healthcare infrastructures, access to quality healthcare services and better health outcomes, the authors suggest. Instead, the causes derive from a complex interplay of many factors such as individual, community and policy-level shortcomings.

The study identified 61 articles from 55 population-based studies from 1990 to 2020 that included roughly 189,000 participants. Of these, approximately 7,000 had manifest glaucoma and about 6,000 suffered from undetected glaucoma.

“Our study shows that a large proportion of glaucoma cases are undetected across communities worldwide, and more so in regions that are more vulnerable to the disease, of which the reasons are multifaceted,” the researchers wrote in their paper. “This calls for a holistic approach that emphasizes the need for collaboration and integration. The problem of glaucoma detection is not new, and its ill effects will only exacerbate with continued inertia. Therefore, it is time to take action.”

Soh ZD, Yu M, Betzler BK, et al. The global extent of undetected glaucoma in adults: a systematic review and meta-analysis. Ophthalmology. April 15, 2021 [Epub ahead of print].