PARTNERS: A CROSS-SECTIONAL STUDY

Researchers for the PAD Awareness, Risk, and Treatment: New Resources for Survival (PARTNERS) program investigated the feasibility of detecting peripheral arterial disease using the ABI in an office-based practice.1 They hypothesized that this disease, particularly when compared with cardiovascular disease, is underdiagnosed and undertreated in terms of both risk modification and use of antiplatelet therapies. Main outcome measures included frequency of PAD detection, physician and patient awareness of PAD diagnosis, and treatment intensity in patients with PAD relative to those with other forms of CVD.      A total of 6,979 subjects aged 70 years or older (or aged 50–69 years if they had a history of smoking or diabetes or both) were screened at one of 350 local primary-care sites. They provided a medical history and underwent ABI measurement with a 5-mHz Doppler device. ABIs were obtained as follows: Systolic blood pressures (SBPs) of the upper and lower extremities were measured while subjects were lying supine; the higher of the two ankle SBPs was divided by the higher of the two brachial SBPs to arrive at the ABI. PAD was defined as an ABI in either leg of 0.90 or lower.     Among 6,417 evaluable subjects, 1,527 (24%) had CVD only, 825 (13%) had PAD only, 1,040 (16%) had both PAD and CVD, and 3,025 (47%) had neither. Among patients with PAD, 457 (55%) were newly diagnosed; among those with PAD and CVD, 366 (35%) were newly diagnosed with PAD. Thus, a diagnosis of new PAD (based on an ABI <0.90) was more likely in subjects without other evidence of CVD than in those with other signs of CVD. In this study, PAD was as common in women as in men, and was detected at high rates in all national regions and in all races (isolated PAD was particularly common in blacks, however). Primary Study Message Kenneth Ouriel, MD, commented that “…the primary message of this study is instructive: PAD is an important marker for systemic atherosclerosis, is easily diagnosed by the Doppler ankle-brachial index within a primary-care setting, and, once identified, should prompt the institution of preventive measures such as lipid reduction, platelet inhibition, and control of hypertension.”2 Only 8.7% of PAD-only subjects had classic Rose claudication. Atypical leg symptoms were much more common, affecting about 50% of this subgroup. Whereas 83% of subjects with a prior PAD diagnosis were aware of the diagnosis, only 49% of their physicians had recognized the diagnosis at the time of screening.  Smoking-cessation interventions were prescribed more frequently for PAD subjects than for CVD subjects. Diabetes was managed similarly in all groups. Treatment of other risk factors (eg, hyperlipidemia, hypertension) was generally more aggressive in subjects with CVD than in those with PAD. Antiplatelet medications (primarily aspirin) were used by a significantly smaller proportion of subjects with new PAD (33%) or prior PAD (54%) than of those with CVD only (71%).  The study authors concluded that PAD is highly prevalent in the primary-care setting, and is easily detected with an ABI measurement during routine office visits. Physicians using a classic history of claudication alone to detect PAD are likely to miss 85% to 90% of PAD cases. Study data also corroborated that patients with PAD are at high risk for other manifestations of atherosclerotic disease, which would likely be reduced by appropriate lifestyle and pharmacologic interventions initiated by primary-care practitioners. References 1. Hirsch AT, Criqui MH, Treat-Jacobson D, et al. Peripheral arterial disease detection, awareness, and treatment in primary care. JAMA. 2001;286:1317-1324. 2. Ouriel K. Detection of peripheral arterial disease in primary care. JAMA. 2001;286:1380-1381.