Lower extremity peripheral artery disease (PAD) affects 10 million adults in the US and increases the risk of mortality and leg amputation. Since it has broad implications for quality of life and maintenance of independent living, the impact of PAD on physical activity and function is of great interest. To characterize the impact of PAD on free-living daily physical activity and examine the value of objective assessment of daily physical activity for PAD management, diagnosis and risk stratification, we propose to evaluate enrollees of the Hispanic Community Cohort Study/Study of Latinos (HCHS/SOL). Participants who were originally studied during 2008-2011 will complete a return in person visit during 2019-2021. Through comprehensive clinical assessment of lower extremity blood vessels, multi-day accelerometry and physical function testing, we address the hypothesis that PAD will be identifiable by suboptimal usual activity patterns including longer sedentary time, higher activity fragmentation and diurnal patterns of activity. The study will also determine the prognostic value of 7-day physical activity, above and beyond self-reported leg symptoms and clinic-based physical function, to predict PAD-associated major health outcomes. Finally, duplex ultrasound of leg arteries in combination with other study assessments will be used to better resolve the population with indeterminant results on peripheral arterial disease clinical test. Results will help to guide the application of both clinical screening protocols and mobile technologies to identify, predict and intervene upon major health sequalae associated with PAD.
This ancillary study to Hispanic Community Health Study/Study of Latinos (HCHS/SOL), an NIH-sponsored community based cohort, proposes to measure resting ankle-brachial index (ABI), toe-brachial index (TBI), ankle waveforms, post-exercise ABI (if resting ABI ?1.4), and leg symptoms as indicators of peripheral artery disease (PAD) as well as 7-day accelerometry (Actigraph) and walking endurance (2-min walk) to assess physical activity and function among ~6,000 individuals aged 45 years and older during HCHS/SOL visit 3 (between 2019-2021). In a subsample of 720 participants with borderline low ABI 0.9-1.0, duplex ultrasound will be conducted as a reference for significant leg artery stenosis. This project will provide robust evidence for the contribution of PAD to reduced physical activity in the community as well as insights on how continuous monitoring with a wrist-worn wearable device would help risk classification in PAD and the diagnostic approach of PAD.
