Research

Should we be worried about glaucoma? Why the prevalence of glaucoma is variably reported

Anthea Worley^a1 and Karen Grimmer-Somers^a1 c1

^a1 Centre for Allied Health Evidence, University of South Australia, City East Campus, North Tce, Adelaide, SA 5000, Australia

Abstract

Aim This paper reports on a recent review of the prevalence of glaucoma, and identifies factors that impact on its variable reporting.

Background Glaucoma is a recognized chronic degenerative health problem worldwide, in which approximately two-thirds of sufferers are undiagnosed. Therefore it is important to better quantify glaucoma prevalence to plan adequate resources for effective risk screening, diagnosis, management and prevention. Accurate prevalence data also assist in determining the nature of relationships between glaucoma and putative risks.

Methods A comprehensive search of peer-reviewed databases was conducted to identify and critically appraise secondary evidence published between 2002 and 2007. Glaucoma definitions, prevalence, incidence and risk factor data were extracted and compared in the context of their population descriptors.

Findings There was no standard definition of glaucoma or standard population descriptors (age, ethnicity, country) utilized by either the primary studies included in the secondary evidence or as inclusion criteria in the secondary evidence. Prevalence for glaucoma of between 1–4% was commonly reported. Despite this, the influence of age and ethnicity on glaucoma prevalence within specific populations was repeatedly highlighted. There was consistency across studies of the decreased risk of white (European) populations compared with other ethnic groups. There was an exponential increase in prevalence of glaucoma over decades of increasing age. There were limited Australian data; however, prevalence of open-angle glaucoma is comparable with international figures. There is a clear need for worldwide agreement on standard epidemiological descriptors of glaucoma, using standard population frameworks, terminology and age groups.

(Received December 16 2008)

(Accepted July 11 2009)

Key words

• glaucoma;
• incidence;
• metasynthesis;
• prevalence;
• risk factors

Correspondence:

^c1 Correspondence to: Karen Grimmer-Somers, Centre for Allied Health Evidence, University of South Australia, City East Campus, North Tce, Adelaide, SA 5000, Australia. Email: Karen.Grimmer-Somers@unisa.edu.au