Glaucoma a risk factor for onchocerciasis, study shows

A positive association between onchocerciasis and glaucoma was found in a study in West Africa, according to a recent report.

The study’s authors, Peter Egbert, MD, and colleagues, note that their findings underline the importance of the eradication of onchocerciasis from West Africa.

Onchocerciasis, a blinding disease that affects an estimated 18 million people worldwide, is typically found in tropical regions, with more than 99% of cases occurring in sub-Saharan Africa.

The subjects of the study were patients at the Bishop John Ackon Christian Eye Centre in Ghana who were undergoing either trabeculectomy for advanced glaucoma or extracapsular extraction for cataracts. All patients were given a skin-snip biopsy for onchocerciasis.

A cross sectional case-control study found that the prevalence of onchocerciasis was 10.6% in those with glaucoma and 2.6% in those with cataracts, according to the authors. After adjusting for age, region of residence and sex, the subjects with glaucoma were found to have three times the odds of testing positive for onchocerciasis, the authors said.

“Little is known about the role of onchocerciasis infection in chronic progression diseases of the eye, such as glaucoma,” the study authors said.

The study is published in the July issue of British Journal of Ophthalmology.

An editorial in the same issue notes that in the World Health Organization’s most recent assessment of worldwide causes of blindness, “onchocerciasis may have made the list for the last time” at No. 8, because of eradication efforts, while glaucoma has moved up to the No. 2 spot.