Purpose
The last major systematic review on POAG prevalence was published a decade ago. Many new studies have emerged, and the definition of glaucoma in population surveys has changed. We performed a systematic search and meta-analysis on POAG prevalence. We aim to study: the relationship of POAG prevalence with age, gender and ethnicity, the trend in POAG prevalence through time, the effect of study design factors on prevalence, and to estimate the global prevalence and case burden of POAG.
Methods
A systematic search was performed on MEDLINE, EMBASE and Web of Science up to October 2014. Studies reporting POAG prevalence in population surveys which performed optic disc assessment on all subjects were included. Multi-level binomial logistic regression of log-odds of POAG was used to examine the effect of age and gender amongst populations of different geographic and ethnic origins, adjusting for study design factors over time.
Results
Data were available from 82 studies (37 countries, 215870 participants, 5413 POAG cases). All ethnic groups showed a log linear increase in POAG prevalence with age. Blacks showed the highest POAG prevalence, at 5.2 % (95%CI 3.6,6.8%) at 60 years, rising to 12.2% (95%CI 8.6,15.8%) at 80 years. Increase in POAG prevalence per decade of age was greatest among Hispanics (2.31, 95%CI 2.12,2.52) and Whites (1.97, 95%CI 1.83,2.11), and lowest among East and South Asians (1.48, 95%CI 1.39,1.57; 1.56, 95%CI 1.31,1.86 respectively). Men were more likely to have POAG than women in all ethnic groups (1.32, 95%CI 1.23,1.42). Surveys performed in 1960-1979 reported significantly lower POAG prevalence than those after year 2000 (0.48, 95% CI 0.22, 0.93), possibly reflecting changing definitions of glaucoma. Studies that performed visual field tests on all participants had a higher POAG prevalence compared to those with visual fields data in a sub-set. An estimated 49.4 million people (95%CI 47.2, 51.7 million) were affected by POAG in 2010, rising to 64.1 million (95%CI 61.3, 66.8 million) in 2020. The increase will be more rapid in developing countries than Europe and North America due to population expansion.
Conclusions
This study provides the most comprehensive and current evidence on POAG prevalence. Our prevalence estimates are more precise than previous published data due to the large dataset. The results will be useful to healthcare planning.