People who wait more than six months for cataract surgery may experience vision loss, reduced quality of life and more falls, a review of international studies suggests.

Cataracts are the most common eye disorder in North America. With cataracts, the lens loses its clearness, interfering with vision. About half of people between 55 and 64 and 85 per cent of people over 75 will develop cataracts when they are monitored over a 10-year period, a Wisconsin study suggests.

"It would be like looking through a cloud," said study author Dr. William Hodge, an associate professor of ophthalmology at the University of Ottawa Eye Institute.

"The colours go, detail goes and there's a lot of glare often with cataracts, so it's very tough under intense lighting conditions, [such as] driving at night."

Cataracts are treated with surgery under local anesthetic. The procedure involves removing the cloudy lens and replacing it with a clear plastic lens.

In Tuesday's Canadian Medical Association Journal, Hodge and his colleagues reviewed 27 studies on waiting times for cataract surgery, aiming to find out when the wait crosses over from being inconvenient to harming health and quality of life.

The cost of waiting

"Patients who waited more than six months to receive cataract surgery experienced more vision loss, a reduced quality of life and had an increased rate of falls compared with patients who had wait times of less than six weeks," the study's authors concluded.

The difference between waiting times of six weeks and six months remains a grey area that hasn't been well studied, which makes it difficult to define reasonable benchmarks, the researchers said.

Most jurisdictions in Canada have set a 16-week maximum waiting time for cataract surgery — the time-frame recommended by the Canadian Ophthalmological Society and the Wait Times Alliance, which provides advice to federal, provincial and territorial governments on medically acceptable waiting-time benchmarks

But statistics on waiting times for cataract surgery do not take into account the long time that may pass between visiting a family doctor and followup with a specialist. The first wait may even exceed the time from surgical booking to surgery, the study's authors said.

The Wait Times Alliance acknowledged that a patient's wait begins once a primary care provider decides a diagnostic test or clinical intervention is needed, the researchers added.

Last week, the alliance gave provinces and territories a grade of B overall for cataract surgery waits, up from C last year.

The extra effort could help shorten waits in the next couple of years. Over the next 10 to 15 years though, demand for cataract surgery could grow as baby boomers age and the number of ophthalmologists decline, said Dr. Lorne Bellan, chair of the alliance.

With files from the Canadian Press