Subclinical Peripheral Arterial Disease is Highly Prevalent in Mexican Americans and is Associated with Decreased Walking Ability

The risk factors and symptoms for subclinical lower extremity peripheral arterial disease (PAD) have not been well characterized in Hispanics, and even less in Mexican Americans. This is despite common cardiovascular risk factors, such as diabetes and obesity, being prevalent in these populations. The aim of this study was to assess the multivariate PAD associations, describe the symptoms of subclinical PAD, and characterize the walking impairment in a population sample of Mexican American adults in Cameron County, Texas. The Cameron County Hispanic Cohort (CCHC) is a prospective, randomly- ascertained, population-based cohort that assesses demographic and clinical characteristics from MA households in Cameron County, Texas. In addition to a detailed clinical history and examination, participants underwent measurement of bilateral ankle brachial indices (ABI) using a Smartdop® 30EX V Doppler (Koven Tech, St. Louis, MO). The higher and lower of the two pedal pressures for each limb were used for calculating ABI-High and ABI-Low, respectively. ABI was calculated by dividing the pedal pressures by the higher of the two brachial pressures. The Walking Impairment Questionnaire was used to assess leg pain symptoms, walking speed, and walking distance. The San Diego Claudication Questionnaire was used to screen for the presence of different leg pain categories. Data were obtained from 394 subjects; 253 (55.7%) were female. Mean age was 54.1 ± 1.3, 26.7% had diabetes, and 9.9% were smokers. The prevalence of PAD using ABI-High and ABI-Low was 3.5% and 10.6%, respectively. The prevalence of poorly compressible arteries (ABI-High \u3e 1.4) was 4.3%. Age was independently associated with PAD (ABI- High) and male gender was associated with poorly compressible arteries. PAD (ABI-Low) was not associated with any risk factors. There were no significant differences between the prevalence of leg pain symptoms in participants with PAD (ABI-High) and participants without PAD. Participants in the PAD (ABI-High) group had significantly lower walking speed and walking distance scores compared to non-PAD participants. Older age, obesity, and hypertension were associated with lower walking distance and walking speed. PAD (ABI-High) was only associated with decreased walking distance. This is one of the first population-based studies to assess the prevalence, risk factors, and symptoms of early, subclinical PAD in MAs. The at-risk cohort had a PAD prevalence that is higher than previously reported by the population-based Hispanic Community Health Study – Study of Latinos. The significant differences in walking speed and walking distance scores between participants who have subclinical PAD and participants with normal ABIs highlight the early decline in walking ability experienced by individuals with incipient PAD even when no leg pain symptoms are present