Abstract 12537: Sedentary Behavior is a Stronger Risk Factor Than Diabetes for Incident Peripheral Artery Disease: Data From the Henry Ford Exercise Testing (FIT) Project

Abstract

Introduction: Age, diabetes (DM) and smoking are risk factors related to developing peripheral artery disease (PAD). Little is known about the strength of the association of sedentary behavior (SB) or fitness relative to traditional risk factors, and the risk of PAD. Hypothesis: SB and fitness are independently related to risk of PAD, but their relative contribution is less than DM and smoking. Methods: We assessed 41,268 patients (pts) (age= 55±12 yr, 51% male, 64% white) from the Henry Ford Exercise Testing (FIT) who completed a clinically ordered exercise stress test between January 1991 and June 2009. Fitness (metabolic equivalents of task, METs) was estimated from peak treadmill speed and grade. Patients were asked about current exercise habits and coded as sedentary if not performing regular aerobic mode exercise. Patient self-report and medical records were used to determine smoking history and DM. Those with established PAD at the time of testing were excluded. ICD9 codes 440.XX and 443.9 identified first incidence of PAD from test date up to June 2010. Using multivariable Cox regression (Wald X 2 , α <0.05) we report on the top 5 predictors of time to incident PAD in ALL pts and stratified by race. Results: During a median follow-up of 7.1 yr (IQR 4.2-11.1 yr) there were 2,596 (6%) incident diagnoses of PAD. Wald X 2 values were rank ordered (Table). SB and fitness were independently related to time to incident PAD. SB ranked the 3 rd strongest variable for both ALL (HR=2.5 [2.2, 2.9]) and WHITE pts (HR=2.5 [2.1, 2.9]). For BLACK pts SB ranked 2 nd (HR=2.7 [2.1, 3.6]), above DM and smoking. Fitness ranked 5 th for ALL and BLACK pts, and 6 th in WHITE pts. Conclusion: In ALL pts, and WHITE and BLACK pts separately, SB was strongly associated with time to incident PAD, and explained more of the variation in incident PAD than DM. In BLACK pts SB was also stronger than smoking. Further research is needed to clarify the role of SB as a potential emerging modifiable risk factor for the development of PAD.