Prostaglandin analogs (PGAs) have long been a first-line treatment for glaucoma, yet previous research has cautioned that this drug class could cause some unwanted side effects, including uveitis and cystoid macular edema (CME). However, upon review of limited prospective investigations, a new study in the British Journal of Ophthalmology found PGA-associated CME and uveitis were rare complications.

Researchers from Canada did a systematic review of 214 studies (23,232 patients) that evaluated topical PGAs in patients with ocular hypertension or open-angle glaucoma. They found the incidence of uveitis or CME among PGA users was very low, only 0.22% and 0.09%, respectively, notes researcher Chloe Gottlieb, MD, of the University of Ottawa Eye Institute. Of those that developed CME, 98% had recent ocular surgery, aphakia or a subluxed IOL.

“We feel that there is a lack of supportive data showing a cause-effect relationship of CME or uveitis associated with PGA use,” Dr. Gottlieb says. “Data suggests that PGAs could be used in the majority of non-surgical patients without concern of causing CME or uveitis.”

The studies that reported uveitis did not comment on whether the affected eyes were pseudophakic or phakic. For the patients with CME, 35.2% were pseudophakic, 23.5% had previous history of uveitis and 11.8% had previous retinal vein occlusions. These factors may contribute to a higher susceptibility of developing CME, the study suggests.

Of note: A higher frequency of both uveitis and CME were found among latanoprost users compared with bimatoprost. Additionally, 21 case studies reported CME in 48 eyes in 43 patients, and 47 of 48 eyes (97.9%) had previous incisional ocular surgery.

The case studies reported reversibility in all eyes affected with CME or uveitis either after discontinuation of PGAs alone or with medical treatment, the study reports.