In patients with pulmonary arterial hypertension (PAH), daily step count as measured by a wrist-worn accelerometer—the Fitbit ChargeHR—correlates with patients’ 6-minute walk distance (6MWD) and their ability for self-care, according to data presented in Washington, DC, in late May at the American Thoracic Society 2017 International Conference. These researchers from the Cleveland Clinic concluded, therefore, that the Fitbit ChargeHR may be useful in measuring activity and change over time in these patients.
“There are a lot of us, and our patients, commonly wearing devices like the Fitbit or different kinds of activity monitors. They give us a lot of information. And all of us look at our phones or our devices, and look at how many steps we are walking, what our heart rate is, things like that,” said lead author Sameep Sehgal, MD, pulmonary clinical care fellow, Respiratory Institute, Cleveland Clinic, Cleveland, OH. “We wanted to see if we could use these devices to monitor our patients with lung disease,” he added.
Dr. Sehgal and his colleagues prospectively assessed the use of a wrist accelerometer, the Fitbit ChargeHR, to determine its value as a monitoring tool in PAH patients. They presented their initial 2-week data, and will continue their study.
They enrolled 30 ambulatory patients with WHO group I PAH (mean age: 50.49 years; mean 6MWD: 368.6 mm; mean WHO functional class [FC]: I in 10%, II in 46%, III in 36%, IV in 2%), who wore a Fitbit ChargeHR until their next follow-up visit. During these visits, researchers recorded 6MWD test, and conducted physical exams, WHO functional class stratification, and, if clinically indicated, serum biomarker and echocardiography (ECHO) testing.
In the first 2 weeks, mean daily step count and peak daily 6MWD step counts (r=0.44, P=0.01) correlated with baseline 6MWD. Dr. Sehgal and colleagues also found that mean daily step count correlated with patient ability for self-care, but not with mobility, usual care, anxiety, or pain.
These researchers also observed no correlation between either daily step count or 6MWD with NTproBNP levels and ECHO parameters, including right atrial (RA) dilatation, left atrial (LA) dilatation, right ventricular (RV) function, and right ventricular systolic pressure (RVSP).
“It’s too soon to use the Fitbit and similar devices in clinical practice, but I think—going forward—there will be a role for activity monitors in patients. There is a lot that needs to be sorted out before we do this, things like: What is the right device? What are the parameters we look at? Who is going to monitor all of this?” said Dr. Sehgal.
“So there’s a lot more to be done before it hits prime time, but what I suggest as the next step is to start including activity monitors in clinical trials, get more data, and see what is the best way to use it. So watch out for the next few years; maybe a Fitbit or similar devices will be a part of clinical practice,” he concluded.