Could older Australians soon reach for eye drops instead of reading glasses?

Presbyopia — a difficulty in focusing on near objects and text — develops for all as they age, leading many to need reading glasses. Now, a study suggests the solution could lie in the use of special eye drops two or three times a day. This is according to a retrospective study of 766 patients, the majority of whom were found to be able to read an extra two, three or more lines on the Jaeger chart — used for testing near visual acuity — after using specially formulated eye drops, an improvement that was sustained for up to two years.

“We conducted this research due to the significant unmet medical need in presbyopia management,” said Dr Giovanna Benozzi, Director of the Center for Advanced Research for Presbyopia in Buenos Aires, Argentina. “Current solutions such as reading glasses or surgical interventions have limitations, including inconvenience, social discomfort, and potential risks or complications.

Dr Giovanna Benozzi.

“There is a group of presbyopia patients who have limited options besides spectacles, and who are not candidates for surgery; these are our primary focus of interest. We sought to provide robust clinical evidence supporting an innovative pharmacological solution to offer patients a non-invasive, convenient and effective alternative.”

Developed by Benozzi’s father, the late Dr Jorge Benozzi of the same centre, the eye drops contain a combination of two active agents: pilocarpine — a drug that constricts the pupils and contracts the ciliary muscle controlling the eye’s accommodation for seeing objects at varying distances — and diclofenac — a non-steroidal anti-inflammatory drug that reduces inflammation and the discomfort that pilocarpine often causes.

The eye drops were administered to patients twice a day, usually on waking and again approximately six hours later, with an optional third dose if symptoms recurred or additional visual comfort was needed. Divided into three groups, the patients consisted of 373 women and 393 men (with an average age of 55), and were to receive one of three eye drop formulations. There was a fixed dose of diclofenac in each formulation, but concentrations of pilocarpine were 1%, 2% and 3%.

“Our most significant result showed rapid and sustained improvements in near vision for all three concentrations. One hour after having the first drops, patients had an average improvement of 3.45 Jaeger lines. The treatment also improved focus at all distances,” Benozzi said. “Impressively, 99% of 148 patients in the 1% pilocarpine group reached optimal near vision and were able to read two or more extra lines. Approximately 83% of all patients maintained good functional near vision at 12 months. Importantly, no significant adverse events like increased intraocular pressure or retinal detachment were observed.”

No patients discontinued the treatment and adverse side effects were mild — the most common being temporary dim vision, which occurred in 32% of cases, irritation when the drops were instilled (in 3.7%) and headache (in 3.8%). The improvement in the patients’ vision was sustained for up to two years, with a median duration of 434 days. The study is said to be significant as the first systematic evaluation comparing three different pilocarpine concentrations in combination with diclofenac. That it is a retrospective, single-centre study is a limitation, which could limit the generalisability of the findings and introduce selection bias.

Top image credit: iStock.com/RossHelen