Tripped up by a bug: Infection may cause falls, especially in older people, study suggests

Bloodstream, urinary and respiratory infections are the most common culprits for infection-related falls, according to the Massachusetts General Hospital study. The findings also suggest that while these falls may be more common in the elderly, they shouldn't be overlooked in younger people: 20 percent of patients in the study were younger than 65.

"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," said Farrin A. Manian, MD, MPH, principle investigator of the study, a clinician educator in the Division of General Medicine at Massachusetts General Hospital in Boston and a visiting associate professor at Harvard Medical School. "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."

Although it's unclear how many falls are caused by infection overall -- other research puts the number between 20 and 45 percent -- it's clear that many people, including family members, caregivers and even some healthcare providers, don't recognize the connection. People can fall because the infection may cause low blood pressure -- and therefore lightheadedness and dizziness -- or because it adds to confusion in older patients with dementia, according to the researchers.

Researchers analyzed 161 patients who went to the emergency room because they fell and were subsequently diagnosed with a coexisting infection. Of those, 71 (44.1 percent) had a urinary tract infection, 64 (39.8 percent) had a bloodstream infection, 37 (23.0 percent) had a respiratory infection and 9 (5.6 percent) had an infection of the heart valve. A coexisting infection was not initially suspected in 41 percent of the patients, likely because the majority (56 percent) had only one or none of the common signs of infection such as fever, rapid respiration rate, rapid heart rate, or abnormal white blood cell count. Specifically, only one in five had a fever and one in four did not have any criteria for significant inflammatory response.

The findings suggest that family members, care givers and healthcare providers shouldn't rush to judgement about the cause of a fall, particularly in an older person, and should consider whether the person was ill or not feeling well before the incident happened to ensure the patient is diagnosed appropriately and can receive timely treatment.