Association of accelerometer-derived step volume and intensity with hospitalizations and mortality in older adults: A prospective cohort study

Purpose: This study aimed to examine the associations of accelerometer-derived steps volume and intensity with hospitalizations and all-cause mortal-ity in older adults.Methods: This prospective cohort study involved 768 community-dwelling Spanish older adults (78.8 +/- 4.9 years, mean +/- SD; 53.9% females) from the Toledo Study for Healthy Aging (2012-2017). The number of steps per day and step cadence (steps/min) were derived from a hip-mounted accelerometer worn for at least 4 days at baseline. Participants were followed-up over a mean period of 3.1 years for hospitalization and 5.7 years for all-cause mortality. Cox proportional hazards regression models were used to estimate the individual and joint associations between daily steps and stepping intensity with hospitalizations and all-cause mortality.Results: Included participants walked 5835 +/- 3445 steps/day with an intensity of 7.3 +/- 4.1 steps/min. After adjusting for age, sex, body mass index (BMI), education, income, marital status and comorbidities, higher step count (hazard ratio (HR) = 0.95, 95% confidence interval (95%CI: 0.90-1.00, and HR = 0.87, 95%CI: 0.81-0.95 per additional 1000 steps) and higher step intensity (HR = 0.95, 95%CI: 0.91-0.99, and HR = 0.89, 95%CI: 0.84-0.95 per each additional step/min) were associated with fewer hospitalizations and all-cause mortality risk, respec-tively. Compared to the group having low step volume and intensity, individuals in the group having high step volume and intensity had a lower risk of hospitalization (HR = 0.72, 95%CI: 0.52-0.98) and all-cause mortality (HR = 0.60, 95%CI: 0.37-0.98).Conclusion: Among older adults, both high step volume and step intensity were significantly associated with lower hospitalization and all-cause mortality risk. Increasing step volume and intensity may benefit older people.

Automated summary

The study found that higher step volume and step intensity were significantly associated with lower risk of hospitalizations and all-cause mortality in older adults. Increasing step volume and intensity may benefit older people.