Abstract MP087: Relation of Risk Factor Profile at Baseline and 39-Year Follow-up to Peripheral Arterial Disease - - The Chicago Healthy Aging Study (CHAS)
Background: Low burden of CVD risk factors (RF) at younger ages is associated with substantially reduced risk for future clinical CVD events. There is no information available regarding associations of long-term patterns in RF profile, from young adulthood to older age, with prevalence at older age of low ankle brachial index (ABI), a marker for peripheral arterial disease (PAD).
Methods: Using data from the Chicago Healthy Aging Study (CHAS), we assessed associations of patterns in RF profile -- from baseline (1967-73) to follow-up (2007-10) -- with prevalence of PAD at follow-up (see Table for definitions of RFs and RF groups). ABI was calculated as the ratio of Doppler recorded systolic pressures in the lower and upper extremities, and categorized as follows: low ABI/PAD (ABI<1.00) vs. normal (1.00 ≤ABI ≤1.40). Participants with an ABI >1.40 (n=24) were excluded from the analysis.
Results: The study sample consisted of 1,340 participants (27.8% women, 9.2% African Americans) ages 24-45 years, free of major ECG abnormalities and MI at baseline. After 39 years of follow-up, 15.5 percent of persons with no adverse baseline RF levels remained RF-free at follow-up (Group A). The prevalence of PAD was lowest in this Group A (3.7%) and highest (19.9% -- 5 times higher) in Group E, with ≥2 RFs at both baseline and follow-up (p-value < .001). Likewise, with adjustment for baseline age, sex, ethnicity, education, and minor ECG abnormalities, the odds for PAD in Group A was lowest compared with other groups. Further, decrease in number of RFs from baseline to follow-up (Group C) was associated with lower likelihood for PAD compared to increase in number of RFs over time (Groups B and D) and to presence of ≥2 RFs at both baseline and follow-up (Group E).
Conclusion: Long-term absence of risk factors is associated with lowest prevalence of PAD at 39 year follow-up. Greater risk factor burden in young adulthood and development of risk factors over decades were both associated with greater likelihood of PAD later in life.
- © 2012 by American Heart Association, Inc.