Around 2.5 million people aged 65 and older are treated in the ER for falls each year, but researchers who took part in a Massachusetts General Hospital study warn not to automatically assume that "older" means they took a tumble because they're feeble, clumsy, or suffering from poor eyesight or dementia.

Instead, per the Telegraph, there may be a more surprising cause, scientists announced at the Infectious Diseases Society of America's annual meeting: an infection. Urinary tract, bloodstream, and respiratory infections are the most common culprits when infections are involved—all of which can often lead to dizziness, low blood pressure, and other symptoms that may precipitate a fall, a press release notes.

The release adds that while it's currently unclear how many falls are actually caused by infection—estimates based on previous research range from 20 to 45 percent —researchers wanted to find out what kinds of infections afflicted those who had fallen because of them.

How the study was conducted, per Forbes: Reviewing the hospital's medical records from 2000 to 2014, researchers whittled its group of subjects down to 161 patients who had suffered a fall and been determined to have a coexisting systemic infection (CDI).

Of the 161, 44 percent had a UTI, almost 40 percent had a bloodstream infection, and 23 percent had a respiratory infection, the release notes; meanwhile, almost 6 percent had a heart valve infection.

What made the results of the study somewhat surprising: A majority of the subjects (56 percent) had few or no common symptoms of an infection, leading to 41 percent of them being misdiagnosed initially.

And while many warnings are coming out of the study advising caretakers not to make assumptions about their elderly loved ones' falls, the younger set doesn't get off scot-free: About 20 percent of the subjects who fell because of an infection were under the age of 65, the Telegraph notes.

(Now we need to look into why older people are falling more often.)

This article originally appeared on Newser: Study Finds Surprising Reason Behind Many Falls

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