Fall risk may rise after cataract surgery

An opthalmologist removes a cataract from an eye (Jay Directo, AFP/Getty Images)

NEW YORK (Reuters Health) - Contrary to some past research, a new study finds that elderly adults who have cataract surgery could face an increased risk of falls and fractures in the next year - at least if they have only one eye done.

The increase was seen mostly in patients age 80 and up, and researchers say it's not clear what factors - related to the surgery or not - might explain the added risk.

A cataract is a clouding of the eye's lens, usually caused when proteins in the lens condense into clumps with age. Some studies, but not all, have suggested that cataract removal curbs older adults' risk of falls and bone breaks.

In the new study, researchers looked at records for more than 15,000 Australian adults who'd had a first-time cataract surgery.

Overall, 600 were hospitalized for a fall-related hip fracture or other injury - either during the year before or the year after the eye surgery. And the risk, it turned out, was greater in the year after.

There were 273 hospitalizations in the year before surgery, and 352 in the year after.

When the researchers accounted for some other factors - like a patient's age and other medical conditions - the risk of hospitalization was 27 percent higher in the year after cataract surgery.

The findings, reported in the Journal of the American Geriatrics Society, conflict with a U.S. study published just last month.

That study reviewed Medicare records for one million older Americans with cataracts. It found that those who had cataract surgery had a somewhat lower risk of breaking a bone in the following year, versus those who did not have surgery.

(See Reuters Health story of July 31, 2012 http://reut.rs/QtQx21).

But there are differences in the study groups that may help explain the conflicting findings, according to Lynn B. Meuleners, of Curtin University in Perth, Australia, who led the new study.

For one, she said in an email, her study looked at patients who'd had cataract surgery in only the "first eye." In Western Australia, where the study was done, people typically wait six months to a year to have their second eye treated, if needed.

Meuleners suspects that may be a factor in the higher fall risk after surgery. If people had "lopsided vision" after single-eye surgery, that might have made them more prone to falls.

"It may also have been due to wearing old glasses and having poor vision in the corrected eye because of the glasses, and poor vision in the other eye due to cataract," Meuleners explained.

"One would expect better vision if both eyes had successful cataract surgery in a short period of time - generally 2 to 6 weeks," Meuleners said. "Therefore, ‘both eye' patients may have lower risk of falls if vision is a risk factor."

The U.S. Medicare study, she noted, did not look separately at patients who'd had surgery in only one eye or had both eyes done with a short wait in between.

According to the U.S. National Eye Institute, the typical wait time between two cataract surgeries is four to eight weeks.

It seems logical that cataract surgery could prevent some fall-related injuries, since vision problems are considered a risk factor for older people's falls.

But so far, research findings have been mixed as to whether that's true.