"The strongest evidence is for exercise that contains multiple components such as strength and balance training, whether carried out in groups or prescribed for people in their homes," Lesley Gillespie and Clare Robertson, who worked on the new research review, told Reuters Health by email.

"These programs appear to reduce the number of falls experienced by about on average 30 percent and the number of people falling by about 20 percent," they said.

About a third of Americans over 65 fall each year, resulting in nearly 20,000 deaths and more than two million emergency room visits, according to the U.S. Centers for Disease Control and Prevention.

With the right interventions, those numbers could be much lower, suggest the new findings, published Wednesday in The Cochrane Library.

Gillespie and Robertson, both at the University of Otago in Dunedin, New Zealand, and colleagues looked at 159 studies with more than 79,000 seniors who had been randomly assigned to a fall prevention program, a program not designed to decrease falls, or no intervention at all.

While some studies have suggested vitamin D supplements might help stave off falls by boosting muscle strength, the researchers found that wasn't the case, based on 16 studies with more than 29,000 participants.

Some interventions to treat vision problems, such as adjusting to new glasses, also increased the risk of falls.

Studies with thousands of participants showed exercise, including Tai Chi, effectively cut the risk of falling. So did home safety assessment and modification, especially when carried out by an occupational therapist.

A $28 BILLION PROBLEM

According to data released earlier this year by the CDC, nearly 38,000 Americans 65 and older are treated in ERs each year after tripping on a rug or a carpet. More than a third of the falls happen in the bathroom.

Ways to make your home safer include removing things like papers and books from the floor and stairs, getting rid of small rugs or taping them to the floor, improving lighting around the house, having grab bars in the bathroom and using non-slip mats in the bathtub, the agency says.

Gillespie and colleagues also found a trial including 93 participants that showed taking seniors off psychiatric medications lowered the rate of falls by two-thirds.

Another trial showed cataract surgery in women prevented falls, as did getting a pacemaker for people with a heart problem called carotid sinus hypersensitivity.

"If someone is worried about falling they should talk to their family physician or any health professional they are attending as there may be a specific cause or causes that can be addressed," the researchers added in their email.

The CDC estimates that the medical costs of falls exceed $28 billion a year. A recent study from Florida suggests a workshop-based community fall prevention program can be implemented for an average of $325 per completer over the first year and $176 the following year.

Although curbing falls might go a long way toward preventing broken bones, which can take a large toll on elderly people's health, the researchers say the exact effect on fractures is unclear.

"Our results were not particularly informative regarding fracture prevention as not all studies included this outcome," the note.

SOURCE: bit.ly/UKfeFR The Cochrane Library, September 12, 2012.

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