Longer Fitbit records show stronger links to disease
Year-long step counts were linked to 389 existing and 61 new disease outcomes, versus 271 and 33 for one-day counts.
An observational study analysed 11 million days of Fitbit data from 29,303 participants in the All of Us Research Program. Researchers compared daily step counts, peak stepping rates and heart rate per step across measurement windows ranging from one day to one year.
They examined links with more than 700 disease outcomes that arose later and more than 1,400 already present. Longer measurement windows yielded stronger, more stable associations, although the activity measures were closely correlated. Differences between links to existing and later disease suggested that activity measures may act both as early markers of disease and as risk factors.
Why it matters
For healthy aging, an important question is whether activity patterns signal emerging disease or point to future risk.
Caveats
This observational study could not establish whether activity affected disease risk or developing disease changed activity. The findings came from All of Us participants with Fitbit data.
