Wearable devices like Fitbits and Apple Watches can be used to estimate exercise capacity and determine the health status of patients, says a new study.

Determining how far patients with pulmonary disease can walk in six minutes has long been an effective clinical tool to help physicians determine their exercise capacity, as well as to aid in predicting health outcomes and mortality.

The new research suggests that devices like Fitbits and Apple Watches can replace the standardised six-minute walk distance test, which is usually conducted in a clinical setting.

Data from wrist-worn step trackers may be used in clinical care at higher intervals to effectively monitor patient progress and disease management, said the study.

“For patients, this means we can track their progress more frequently in a manner that’s less expensive and more convenient than current standardised testing,” said lead investigator of the study Denitza Blagev from Intermountain Healthcare in the US.

The six-minute walk distance is an important, objective standard used to assess exercise capacity.

Patients walk for six minutes and, then based on how many metres they cover in that time, physicians can predict outcomes and mortality for patients with chronic obstructive pulmonary disease (COPD) and cardiovascular diseases.

“Normally, the 6WMD (six-minute walk distance) test is done every few months or once a year. Now, we may be able to measure patients on a regular basis and know if we need to intervene if their estimated 6WMD by step count changes,” said Blagev.

In the study, researchers conducted a 12-week, blinded, randomised, cross-over trial with 52 patients, a group that included adults with a history of respiratory problems during periods of elevated air pollution. Wrist step counters tracked patient steps for those 12 weeks and patients also filled out respiratory symptom questionnaires.

Researchers found they could effectively estimate a patient’s six-minute walk distance results by using step counters, instead of having patients come in a clinical setting to do the test.

“Instead of having one measurement every few months, you could have weekly measurements, and have information at disease progression at more frequent intervals. This is a significant improvement and enhanced convenience for our patients,” said Blagev.

Findings from the study were were presented on Sunday at the European Respiratory Society International Congress meetings in Madrid.