Study: Low lifetime recreational activity may increase prevalence of PAD

New research published in the August 2011 issue of the Journal of Vascular Surgery®, the official publication of the Society for Vascular Surgery®, indicates that there may be a connection between low lifetime recreational activity (LRA) and increased peripheral arterial disease (PAD). PAD narrows the leg arteries, reducing blood flow to the limbs. Approximately eight to 12 million people have PAD which impairs the ability to walk and reduces the quality of life.

Research co-author John P. Cooke, MD, PhD, is a professor of medicine at Falk Cardiovascular Research Center at Stanford University Medical Center in Stanford, CA. Dr. Cooke noted that the relationship between LRA and the risk of developing PAD had been unknown.

"Our study is the first to reveal that a person's level of recreational activity is associated with whether or not they develop PAD," said Dr. Cooke. "We studied 1,381 patients between April 2004 and January 2008 who were referred to either Stanford or Mt. Sinai Medical Center in New York City for elective coronary angiography. Our goal was to understand what environmental or genetic factors increased the risk for PAD. In the current study, we wanted to know if a lifetime of recreational activity would protect against developing PAD."

PAD was defined as ankle-brachial index (ABI) less than 0.9 at the time of presentation or a history of revascularization of the lower extremities regardless of ABI measure. "We used a validated physical activity questionnaire to retrospectively measure each patient's LRA," he said. "We assessed the amount of recreational activity that people had engaged in during their adult life. Our LRA questionnaire assessed the frequency and duration over their lifetime that each individual engaged in vigorous activity such as jogging, moderate activity such as golf, and light activity such as strolling. Statistical analyses were used to assess the independent association of LRA to ABI and the presence of PAD."

Evidence of PAD was present in 19 percent (258 patients) of the patients. The least active patients had a significantly lower average ABI. A higher proportion had PAD (25.6 percent compared to 13.7 percent of non-sedentary patients). Also, they had greater diastolic blood pressure and were more likely to be female.

In a regression model, including traditional risk factors and LRA, multivariate analysis showed: age, female gender, fasting glucose, cumulative years of tobacco pack use, systolic blood pressure and serum triglycerides were independent negative predictors of ABI. Patients who reported no regular LRA had a 1.5 increased chance of having PAD after corrected for other cardiovascular risk factors.

"In our study, there was a group of people who engaged in absolutely no recreational exercise," said Dr. Cooke. "These individuals were more likely to develop PAD later in life compared with others who engaged in any recreational activity.

"Our study adds important new information regarding the association of recreational activity and the prevalence of PAD. Although it is well-known that patients with PAD are sedentary, it was not known if this was a cause or an effect of PAD. Our study indicates that people who are sedentary during their lifetime are more likely to develop PAD. The LRA questionnaire may be a useful clinical screening tool for PAD risk. Based on out study, it seems likely that people who regularly engage in recreational activity (even mild exercise such as strolling) throughout their lives are much less likely to develop lifestyle-limiting and limb threatening PAD."