Functional decline common, persistent among older adults hospitalized with influenza

In a study of older adults hospitalized with influenza and other acute respiratory illnesses, functional decline was common, and persistent and catastrophic for some, researchers reported in the Journal of the American Geriatrics Society.

“Even though we often think of influenza in terms of its short-term impact, a substantial proportion of older adults hospitalized with influenza will suffer longer-term declines in function, which can greatly affect their quality of life, independence and care/support needs,” Melissa K. Andrew, MD, PhD, associate professor in the division of geriatric medicine at Dalhousie University in Halifax, Nova Scotia, Canada, told Healio.

The prospective observational study included 925 patients (mean age, 79 years; 56.1% women) who were enrolled in the Serious Outcomes Surveillance Network of the Canadian Immunization Research Network during the 2011 to 2012 influenza season. Patients were admitted to one of 40 hospitals across seven Canadian provinces with influenza and other acute respiratory illnesses.

Frailty was measured using a frailty index and functional status was measured using the Barthel index, with moderate persistent functional decline defined as a clinically meaningful loss of 10 or more to less than 20 points on the 100-point index. Catastrophic disability was defined as a loss of 20 or more points, which was equivalent to full loss of function in two domains or need for assistance in four domains, according to the study background.

Thirty-seven percent of patients had laboratory-confirmed influenza. Patients with influenza demonstrated lower baseline function (Barthel index, 77 vs. 86.9; P < .001) and higher frailty (frailty index, 0.23 vs. 0.2; P < .001) compared with patients with other acute respiratory illnesses, the researchers reported. Higher baseline frailty was associated with increased odds of functional decline, catastrophic disability and death.

At 30 days after discharge, 18.2% of patients experienced a clinically meaningful functional loss, with half experiencing a catastrophic disability, according to the study.

The association between functional decline and catastrophic disability and frailty was the same for patients with influenza and patients with other acute respiratory illnesses, the researchers wrote.

In total, 78 patients died (12.1% with influenza and 6.2% with other acute respiratory illnesses), 8.2% of patients experienced persistent moderate functional decline and 9.9% of patients experienced catastrophic disability.

“We should consider functional outcomes in clinical settings and research studies for influenza and other respiratory illnesses and infections. Preventing the infection and hospitalization in the first place, including through vaccination, is critical,” Andrew said. “We need more consistent consideration of functional measures and outcomes in research on influenza and other respiratory illnesses and infections both in clinical trials and real-world settings. This will be important for many conditions, including COVID-19.”

For more information:

Melissa K. Andrew, MD, PhD, can be reached at mandrew@dal.ca.

Reference:

Press Release.