But researchers now suggest that clinicians, family members and caregivers consider another offender: infections.
Bloodstream, urinary and respiratory infections are the most common culprits for infection-related falls, according to a study presented Friday in San Diego at an annual meeting on infectious diseases known as IDWeek.
The findings by researchers at the Massachusetts General Hospital in Boston also suggest that while these falls may be more common among those 65 and older, they shouldn't be overlooked in younger people: 20 percent of patients in the study were younger than 65.
Many people, including family members, caregivers and even some clinicians, don't recognize the connection. People can fall because an infection may cause low blood pressure and make someone feel lightheaded or dizzy, or because it adds to confusion in older patients with dementia, according to the researchers.
Farrin A. Manian, a clinician educator at Massachusetts General Hospital and the study's principal investigator, said in an e-mail that he hoped the study could increase awareness of falls as "being a potential manifestation of an infection" for both the public and health-care workers.
"Ultimately, we hope that the public can also become more attentive to subtle signs of infections in some patients, the elderly in particular, so that perhaps these infections can be diagnosed and treated before the fall actually occurs," he said.
Researchers analyzed 161 patients who went to the emergency room at Massachusetts General Hospital because they fell and were subsequently diagnosed with a coexisting infection. Clinicians did not initially suspect infection in 41 percent of the patients because the majority had few, if any, obvious signs, such as fever.
"Over the years I've been struck by the fact that some of the more serious infections I treated were in people who came to the hospital because they fell," Manian said. "Even though many of the patients had vague early signs of an infection, such as weakness, or lethargy, it was the fall that brought them in."
There has been previous research about the association of infections with falls, but those focused primarily in the elderly with dementia and urinary tract infections or people who lived in institutions, he said. The new study is the first to systematically look at the relationship between infections and falls in a general population. Nearly 80 percent of the patients in the study were living at home.