A new study has found a link between the activity levels of elderly people who have just been released from the hospital and the risk that they will require readmission within 30 days.

The investigation draws on data collected from 111 patients aged 65 and older, each of whom was fitted with a “step activity monitor” during his or her hospital stay. Worn on the patient’s ankle, the pager-sized device counted every step the person took during hospitalization and for a week after discharge. 

“We’re using activity here as a biomarker, similar to the way you might use blood pressure,” said University of Texas Medical Branch at Galveston assistant professor Steve R. Fisher, lead author of a paper in Journals of Gerontology A. “While we can’t say whether activity is a cause or effect in these cases, we can use it as a marker to tell us whether a person is at high risk and we need to intervene.”

Geriatricians want to reduce readmissions among the elderly because hospitalization can actually endanger their health by reducing activity levels and contributing to debilitating muscle loss. Hospitals have an additional motivation: in October 2012, Medicare began financially penalizing hospitals with higher than expected 30-day readmission rates for certain diagnoses.

Patients in the study who were rehospitalized also walked markedly less during their hospital stay.

Fisher envisions hospitals using inexpensive electronic pedometers to monitor elderly patient activity in the hospital and for a brief period after discharge. 

“If you suffer congestive heart failure, a nurse will call you during the first week home to ask how whether you’ve gained any weight, because an increase in water retention can be a sign that CHF is exacerbating,” Fisher said. “This is the same kind of principle: we want to know how much people are moving around, because we want to know whether they’re going downhill. The key is to avoid re-hospitalization that often starts a cascade of events that leads to debility.” 

Other authors of the paper include Yong-Fang Kuo, Mukaila A. Raji, James S. Goodwin, Glenn V. Ostir, Gulshan Sharma, Amit Kumar and Kenneth J. Ottenbacher. This research was supported by the National Institutes of Health.