Medical Benefits of a Peripheral Vascular Screening Program
Article Outline
We present preliminary results and analysis of a screening program that has been offered at a community-based hospital since July 2004. The program includes a quick carotid ultrasound study, abdominal aortic ultrasound imaging, and measurement of bilateral ankle/brachial indices (ABI). From July 2004 through January 2006, 1,719 patients were screened, including 1,094 (64%) women and 652 (36%) men. The majority of carotid screens were normal; however, 28.9% (497 patients) had 15-40% stenosis, 1.4% (24 patients) had 40-60% stenosis, and 0.3% (six patients) had >60% stenosis. Sixteen patients (1%) had infrarenal aortic dilation (>3 cm), and an abnormal ABI (<0.90) was detected in at least one limb in 100 patients (5.8%). No procedures resulted from carotid screening; however, two patients underwent urgent repair for 9.3 and 7.5 cm diameter abdominal aortic aneurysms. Abnormal ABI in conjunction with symptoms led to arteriography in three patients, one of whom had iliac stent deployment. This nonselective vascular screening program attracted many new patients into the health-care system. The open/endovascular procedure yield was low, but early disease detection was significant, causing numerous patients to be referred for additional testing and risk factor modification programs. These preliminary data suggest that community-based vascular screening programs play a key role in early vascular disease detection and provide the potential for prevention of disease progression while, at the same time, building sustainable business for hospitals and physicians.
Introduction
Many Americans over age 50 have peripheral arterial disease (PAD). This atherosclerotic disease process may lead to stroke, abdominal aortic aneurysm (AAA) rupture, and limb loss. Until symptoms arise or a critical problem is serendipitously discovered via imaging for another disease process, most patients and even physicians are not aware of this silent syndrome. Early detection of PAD can be life- and limb-saving as well as provide the potential for prevention of disease progression. Selective screening for PAD based on specific risk factors results in the highest yield of significant atherosclerotic findings.1, 2, 3, 4, 5, 6, 7 However, nonselective screening programs may also be able to identify a sizable number of at-risk patients with modifiable atherosclerotic risk factors or threatening arterial lesions. Vascular screening has been aggressively marketed and offered at St. Joseph Hospital in Orange County, CA, since July 2004. In this report, we present preliminary results and analysis of this voluntary nonselective screening program.
Methods
The screening program at the Vascular Institute (VI) of St. Joseph Hospital is entirely voluntary, and the patient charge is $95. The noninvasive laboratory where the screenings are performed is certified by the Intersocietal Commission for the Accreditation of Vascular Laboratories, and the program has received approval by the Institutional Review Board. This peripheral vascular screening program includes a quick carotid ultrasound study to detect plaque and to estimate the degree of stenosis based on high-resolution B-mode imaging, abdominal aortic ultrasound imaging to detect aortic dilation, and measurement of bilateral ankle/brachial indices (ABIs) to detect lower extremity ischemia. A 20-min block of laboratory time is allotted for each patient, and this includes 15 min of technician time. One exam room is reserved for up to four 2 hr blocks of time to accommodate the screening studies. Depending upon need, one room is usually scheduled in this fashion as many as 2 days per week. Sources of patient referrals include newspaper advertisements, event flyers, and hospital newsletters, as well as previously screened patients and local physicians.
The studies are initially interpreted by an ultrasound technician with oversight from three noninvasive laboratory-experienced vascular surgeons, who are part of the VI. Estimated degree of carotid stenosis is stratified into normal (<15%), mild (15-40%), moderate (40-60%), and severe (>60%) based on B-mode imaging of identified plaque. The abdominal ultrasound and lower extremity ABI are considered to be abnormal when the infrarenal aortic diameter is ≥3 cm and the ABI is <0.90. Postscreening results are reviewed with a full-time VI registered nurse who has experience and training in risk factor modification as this relates to PAD. PAD awareness is discussed, and the need for lifestyle modification is reinforced, including a low-fat/-cholesterol diet, regular exercise, and smoking cessation. Patients with abnormal results are referred to one of three VI vascular surgeons on a rotating basis. The VI nurse also makes recommendations regarding secondary physician referral if requested by the patient and encourages patients to acquire a primary-care physician so that a fasting lipid panel can be checked in addition to a baseline hemoglobin A1C, electrocardiogram, etc. Demographic features were not originally recorded during this pilot study. However, they are now recorded for each patient in addition to tracking of postscreening referral pattern, additional studies ordered, and procedures performed as a result of such screening. Statistical analysis was performed using SPSS 14.0 for Windows (SPSS Inc., Chicago, IL).
Results
From July 2004 through January 2006, 1,719 patients were screened, including 1,094 (64%) women and 652 (36%) men. The mean age was 62 years for women and 65 years for men (P < 0.001). The number of patients screened per month averaged 94, with a range of 35-186. The majority of carotid quick screens were normal (69.4%); however, 28.9% had 15-40% stenosis, 1.4% (24 patients) had 40-60% stenosis, and 0.3 % (six patients) had >60% stenosis. Sixteen patients (1%) had dilation (>3 cm) of their infrarenal aorta, and an abnormal ABI (<0.90) was detected in at least one limb in 100 patients (5.8%).
No procedures resulted from carotid screening; however, two patients underwent urgent repair for 9.3 and 7.5 cm diameter AAAs. The rest of the AAAs ranged 3.1-4.9 cm in diameter. Two of these patients are undergoing work-up for elective repair, and the rest are being followed with repeat periodic imaging. Abnormal ABI in conjunction with symptoms led to arteriography in three patients, one of whom had iliac artery stent deployment. Forty-six and 94 additional diagnostic tests were ordered for abnormal screening results in 2004 and 2005, respectively. The majority (60%) of screened patients were referred back to their primary-care physician, but 8% were referred to vascular surgery and 2% to cardiology. Thirty percent of screened patients had had no physician/health-care contact within the 12 preceding months.
Discussion
PAD is a prevalent atherosclerotic disease process that affects millions of Americans and is associated with significant morbidity and loss of life.7, 8, 9 The consequences of undiagnosed and untreated PAD include nonfatal but debilitating thromboembolic ischemic events, increased mortality, and decreased quality of life. Despite these potentially devastating outcomes, PAD has not yet emerged as a major focus of public health awareness efforts.7 In the absence of a national PAD education and detection program, increased diagnostic efforts in community-based programs may be able to identify a sizable number of at-risk patients with modifiable atherosclerotic risk factors or threatening arterial lesions.7 This is particularly important as clinical examination findings are not independently sufficient to include or exclude the diagnosis of PAD with certainty.8
Clearly, selective screening based on readily known and identifiable risk factors for PAD will have the highest yield of significant arterial findings.1, 2, 3, 4, 5, 6, 7 In a community-based stroke screening program, Rockman and colleagues1 discovered that occult carotid artery stenosis was a commonly diagnosed disease among patients aged over 60 with a history of either hypertension, heart disease, or cigarette smoking or a family history of stroke. Screening for AAA and carotid occlusive disease has also been shown to be cost-effective and to compare favorably with screening programs for other disorders in adults.3, 4, 5 Establishing a diagnosis of PAD based on focused risk factors and clinical findings is important because of prognostic and therapeutic implications. However, a nonselective patient-driven program such as ours does uncover the occasional life-threatening peripheral vascular problem and appears to be quite useful from a patient health-care awareness perspective.
Notwithstanding the medical benefits of a PAD screening program, a successful program requires a medical director who has program oversight and functions as the liaison between the VI and hospital administration, dedicated personnel (physicians, nurses, and ultrasound technicians), and an ongoing commitment from hospital administration. In our case, the screening program, which is an integral part of the VI, was built on the backbone of an existing Women's Health Center (WHC). The program was launched 1 year after opening the WHC and followed this existing business model. Existing personnel were used for the new screening program, with additional support staff added as needed. We utilized similar educational materials and marketing techniques and incorporated the call center to streamline patient appointments. In essence, basic requirements for a PAD screening program include personnel (program manager, nurse, program secretary, marketing support staff, and business development person), space (exam room, reception area, and office space), equipment (ultrasound machine, laboratory, electrocardiogram machine, etc.), and educational materials (pre/postscreening packets, handouts, and flyers).
The revenue generated from the screening fee does not fully cover the total noninvasive laboratory unit cost to the facility, although it does cover the direct personnel costs of the VI nurse and ultrasound technician. However, gross margin total dollars into the St. Joseph health-care system is quite significant if the screening study is considered as port of entry for those patients who went on to have additional care within the hospital. While not the original intent of the vascular screening program, this finding does demonstrate that a well-subscribed community outreach program can build sustainable business for hospitals and physicians.
We have also recognized a halo effect as a result of the screening program. Thirty percent of screened patients had had no physician/health-care contact within the 12 preceding months. Yet, after screening, many of these patients requested an appointment with a primary-care physician and were equally as eager to participate in risk factor and lifestyle modification. These additional physician visits in conjunction with further vascular and cardiac testing help to build sustainable business for our health-care system. Finally, the VI was recently awarded a grant from Edwards LifeSciences (Irvine, CA) to provide free screens to seniors on fixed incomes, underserved populations in Orange County, and individuals with low incomes.
Conclusions
This nonselective vascular screening program attracted many new patients into our health-care system. The open/endovascular procedure yield was low, but early disease detection was significant, causing numerous patients to be referred for additional testing and risk factor modification programs. These preliminary data suggest that vascular screening programs play a key role in early vascular disease detection and provide the potential for prevention of disease progression while, at the same time, building sustainable business for hospitals and physicians.
References
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Presented at the 24th Annual Meeting of the Southern California Vascular Surgical Society, Temecula, CA, May 5-7, 2006.
PII: S0890-5096(07)00082-9
doi:10.1016/j.avsg.2006.10.015
© 2007 Annals of Vascular Surgery Inc. Published by Elsevier Inc All rights reserved.
