Abstract
BACKGROUND: As the impact of daily step counts on the risk and burden of various non-communicable diseases (NCDs) in older adults remains unclear, we investigated this association using wearable device data from a large, diverse cohort. METHODS: We conducted a prospective cohort study using the All of Us Research Program, including 2969 older adults (≥55 years) who wore Fitbit devices. Fitbit data were linked with electronic health records, and follow-up continued until July 1, 2022, to assess daily step counts and NCDs. We estimated the new-onset risks (adjusted-hazard ratios [aHRs]) and burdens (years lived with disability [YLDs]) for 105 NCDs. RESULTS: Of the 2969 participants aged ≥55, participants were categorized into a control group with ≥6000 step counts (mean [SD] age, 66.4 [6.9] years; female, 1243 [62.7%]) and a low-step counts with <6000 steps (67.9 [7.4]; 710 [72.1%]). Lower daily step counts were associated with increased risk and/or burden across various NCDs. First, for cardiovascular disease (aHR, 1.17 [95% CI, 1.04-1.33]; YLD, 85.2 [28.9-141.4] per 100,000 populations), chronic respiratory disease (1.23 [1.08-1.40]; 138.5 [4.7-272.3]), digestive diseases (1.18 [1.04-1.34]; 116.9 [37.3-196.4]), and diabetes and kidney diseases (1.29 [1.11-1.51]; 186.3 [11.8-360.7]), lower step counts were linked to both increased risk and burden. Second, for neurological disorders, mental disorders, and substance use disorders, lower-step counts were associated with a higher risk but not burden. Third, for neoplasms and sense organ disorders, lower-step counts were linked to higher burden without changes in risk. CONCLUSIONS: This study provides real-world evidence supporting the critical role of daily step counts in reducing the risk and/or burden of NCDs.