0
We're unable to sign you in at this time. Please try again in a few minutes.
Retry
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
Retry
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Original Investigation |

Relationship Between Regional Spending on Vascular Care and Amputation Rate FREE

Philip P. Goodney, MD, MS1,2; Lori L. Travis, MS3,4; Benjamin S. Brooke, MD, PhD1; Randall R. DeMartino, MD, MS1; David C. Goodman, MD, MS2; Elliott S. Fisher, MD, MPH2; John D. Birkmeyer, MD2
[+] Author Affiliations
1Section of Vascular Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire
2Dartmouth-Hitchcock Medical Center, Dartmouth Institute for Health Policy and Clinical Practice, Lebanon, New Hampshire
3Center for Outcomes Research and Evaluation, Maine Medical Center, Portland
4Center for Health Outcomes and Policy, University of Michigan, Ann Arbor
JAMA Surg. 2014;149(1):34-42. doi:10.1001/jamasurg.2013.4277.
Text Size: A A A
Published online

Importance  Although lower extremity revascularization is effective in preventing amputation, the relationship between spending on vascular care and regional amputation rates remains unclear.

Objective  To test the hypothesis that higher regional spending on vascular care is associated with lower amputation rates for patients with severe peripheral arterial disease.

Design, Setting, and Participants  Retrospective cohort study of 18 463 US Medicare patients who underwent a major peripheral arterial disease–related amputation during the period between 2003 and 2010.

Exposure  Price-adjusted Medicare spending on revascularization procedures and related vascular care in the year before lower extremity amputation, across hospital referral regions.

Main Outcomes and Measures  Correlation coefficient between regional spending on vascular care and regional rates of peripheral arterial disease–related amputation.

Results  Among patients who ultimately underwent an amputation, 64% were admitted to the hospital in the year prior to the amputation for revascularization, wound-related care, or both; 36% were admitted only for their amputation. The mean cost of inpatient care in the year before amputation, including costs related to the amputation procedure itself, was $22 405, but it varied from $11 077 (Bismarck, North Dakota) to $42 613 (Salinas, California) (P < .001). Patients in high-spending regions were more likely to undergo vascular procedures as determined by crude analyses (12.0 procedures per 10 000 patients in the lowest quintile of spending and 20.4 procedures per 10 000 patients in the highest quintile of spending; P < .001) and by risk-adjusted analyses (adjusted odds ratio for receiving a vascular procedure in highest quintile of spending, 3.5 [95% CI, 3.2-3.8]; P < .001). Although revascularization was associated with higher spending (R = 0.38, P < .001), higher spending was not associated with lower regional amputation rates (R = 0.10, P = .06). The regions that were most aggressive in the use of endovascular interventions were the regions that were most likely to have high spending (R = 0.42, P = .002) and high amputation rates (R = 0.40, P = .004).

Conclusions and Relevance  Regions that spend the most on vascular care perform the most procedures, especially endovascular interventions, in the year before amputation. However, there is little evidence that higher regional spending is associated with lower amputation rates. This suggests an opportunity to limit costs in vascular care without compromising quality.

Figures in this Article

Health care costs attributable to critical limb ischemia, the most severe form of peripheral arterial disease (PAD), have been estimated at nearly 5 billion dollars annually for Medicare patients.1,2 Moreover, with the advent of less invasive endovascular techniques, the use of revascularization procedures for critical limb ischemia has increased 4-fold since 2003.3 Therefore, many believe that, in recent years, vascular care aimed at preventing amputation has become increasingly intensive and expensive.4

However, the costs of revascularization for patients who are at risk for amputation, as well as the costs of the amputation procedure itself, remain uncertain. These costs vary significantly according to the type of treatments patients receive. For example, a “plain old” balloon angioplasty requires catheters that cost a few hundred dollars each, whereas the newer atherectomy devices, drug-coated balloons, and other endovascular adjuncts can exceed several thousand dollars for each artery treated.5 Second, although leg bypass surgery is spared the device-related costs of endovascular interventions, the resultant hospital stay nearly always spans several days and is a significant expense.68 And third, the costs related to the amputation procedure itself remain uncertain, and patients undergoing amputation commonly have postoperative complications and a prolonged hospital stay.9,10 A description of spending patterns for patients at risk for amputation, as well as a delineation of relationships between spending on vascular care and amputation risk, may help to guide physicians and policy makers toward establishing value-based guidelines for the treatment of severe PAD.

Therefore, we characterized Medicare spending related to severe PAD in the year prior to amputation, including costs related to the amputation procedure itself. To ensure that we studied vascular care provided to patients with the most severe form of PAD, rather than the discretionary treatment of claudication, we studied the care provided to patients in the year prior to major limb amputation as a result of PAD. Using data from across hospital referral regions as our unit of analysis,11 we examined risk-adjusted relationships between spending and amputation risk.

Database

We used Medicare claims (2003-2010) to identify patients with severe PAD, and then we examined the costs associated with vascular care in the year prior to amputation. We used Current Procedural Terminology codes to define both revascularization procedures and leg amputation procedures (above and below knee only) commonly utilized in the care of patients with severe PAD12 (eAppendix in Supplement). As in prior work, we also ensured that all patients had International Classification of Diseases, Ninth Revision diagnosis codes for PAD and underwent a major above- or below-knee amputation—an indicator of critical limb ischemia.3,13 We recorded the procedure and the age, sex, and race of the beneficiary receiving the procedure. Vital status was determined using the Denominator file, which contains information about eligibility by year for Part B and information about age, sex, and race of eligible beneficiaries (Figure 1).

Place holder to copy figure label and caption
Figure 1.
Data on Patients, Procedures, and Hospitalization Cost From the Year Prior to Amputation in Our Cohort
Graphic Jump Location

We excluded patients younger than 66 years of age, to allow a 1-year “look-back” for comorbidity assessment. Similarly, records with missing values for sex, age, and race strata were also removed from the analysis. We recorded comorbidities, including hypertension, diabetes mellitus, coronary disease, renal insufficiency, cerebrovascular disease, congestive heart failure, and malignancy, measured both individually and in aggregate using the Charlson comorbidity score. We identified each patient's zip code of residence and hospital referral region, as described by the Dartmouth Atlas of Health Care.11 Among the 20 058 patients in our data set, cost data were unavailable in Medicare claims for 1595 patients (8%). These patients were excluded from our analysis; however, they had characteristics similar to those patients who remained in our cohort.

Studying Cost in the Year Prior to Amputation

The severity of PAD can vary significantly, from claudication to limb-threatening ischemia and gangrene. To study a population of patients whose extent of PAD was as similar as possible,13 we examined vascular care during the year prior to amputation. By intent, the extent of PAD is similar across patients studied in this manner because the risk of 1-year limb loss for the entire cohort is 100%.4,14 As reported in prior work,13 the use of this exposure variable (vascular care in the year prior to amputation) allows us to study care aimed specifically at the treatment of severe PAD, rather than the discretionary treatment of claudication.14

Calculating Price-Adjusted Medicare Spending in the Year Prior to Amputation

We studied inpatient costs during the year prior to amputation, including costs related to revascularization, wound debridement, and management of cellulitis. This encompassed both diagnostic (such as a diagnostic angiogram) and therapeutic invasive vascular procedures. We also studied costs incurred during the amputation procedure itself. Spending was aggregated at the level of the hospital referral region, as defined in the Dartmouth Atlas of Health Care.11 Costs were then adjusted for regional differences in Medicare payments, adjusted for inflation given the year of the procedure, and reported as “price-adjusted” Medicare spending.15

Calculating Population-Based Regional Major Leg Amputation Rate

The population-based regional amputation rate was calculated across hospital referral regions, using the total number of major amputations as the numerator and the total number of patients in the region (determined from the midyear census estimate) as the denominator. Toe amputations and forefoot amputations were not considered in this analysis.

Examining Relationships Between Regional Spending and Rates of Amputation

After defining regional spending in the year prior to amputation and calculating population-based regional rates of major amputation, we examined the associations between these 2 variables. These associations were displayed using scatterplots between the exposure variable and the outcome variable, at the regional level. Correlation coefficients were calculated between the exposure and the outcome.

To adjust for differences in patient characteristics across regions, we generated quintiles of spending and population-based amputation rates, and we adjusted for differences in comorbidities and Charlson comorbidity scores across quintiles of spending using backward stepwise logistic regression models. Models were adjusted for patient-level comorbidities as outlined in Table 1, and a cutoff of P < .20 was established for model inclusion. We censored regions where fewer than 11 amputations occurred, in accordance with guidelines regarding preservation of patient confidentiality from the Centers for Medicare and Medicaid Services. All calculations were performed using SAS (SAS Institute) and Stata (StataCorp). Institutional review board approval was obtained from the Committee for Protection of Human Subjects from the Geisel School of Medicine at Dartmouth in Hanover, New Hampshire.

Table Graphic Jump LocationTable 1.  Characteristics of Vascular Amputees in 2007-2009 Medicare Claims, by Quintile of Spending in Year Prior to Amputation on Revascularization/Hospitalization
Patient Characteristics, Revascularization, and Hospitalization Rates

We identified 18 463 patients who underwent a major PAD-related amputation between 2003 and 2010. Overall, patients had a mean age of 78 years, and 51% of the patients were male. Patients commonly had a history of diabetes (49%), heart failure (35%), and coronary disease (14%) (Table 1).

Within this cohort, 11 785 patients (64%) were hospitalized during the year prior to amputation, while the remaining 36% were not admitted for a PAD-related reason during this same period. Of the 11 785 patients admitted to the hospital, 2762 (23%) underwent an inpatient revascularization procedure, and 2491 (21%) had a debridement procedure performed during a hospital admission in the year prior to amputation.

Overall, Amputation-Specific, and Revascularization-Based Spending

The mean total cost of inpatient vascular care in the year prior to amputation, including costs related to the amputation procedure itself, was $22 405 (95% CI, $22 145-$22,666) per patient. The hospital referral regions with the lowest mean spending on overall inpatient care in the year prior to amputation were Bismarck, North Dakota ($11 077 [95% CI, $7399-$14 754]); Lebanon, New Hampshire ($13 206 [95% CI, $8870-$17 541]); and Meridian, Mississippi ($14 120 [95% CI, $10 320-$17 921]). Costs in the year prior to amputation were highest in Paterson, New Jersey ($35 040 [95% CI, $23 658-$46 421]); Ridgewood, New Jersey ($38 070 [95% CI, $7123-$69 017]); and Salinas, California ($42 613 [95% CI, $14 041-$71 185]) (Figure 2).

Place holder to copy figure label and caption
Figure 2.
National Map (A) and Histogram (B) Demonstrating Regional Spending on Vascular Care and Hospitalizations in the Year Prior to Amputation, by Hospital Referral Region
Graphic Jump Location

The mean regional spending on revascularization or debridement (exclusive of the amputation) in the year prior to amputation was $8316 (95% CI, $8150-$8483) per patient. The regions with the lowest mean spending on revascularization or debridement were Muncie, Indiana ($1277 [95% CI, $60-$5582]); Duluth, Minnesota ($3342 [95% CI, $1141-$5542]); and Topeka, Kansas ($4199 [95% CI, $1445-$6953]). The regions with the highest mean spending were St Paul, Minnesota ($14 063 [95% CI, $4698-$23 427]); Toledo, Ohio ($14 107 [95% CI, $9763-$18 450]); and Harlingen, Texas ($14 120 [95% CI, $10 553-$17 686]).

The mean spending for the amputation procedure itself was $14 088 (95% CI, $13 898-$14 278) per patient. The regions with the lowest mean spending on amputation-related hospitalization were Lebanon, New Hampshire ($8368 [95% CI, $6076-$10 659]); Meridian, Mississippi ($9408 [95% CI, $7333-$11 484]); and Bismarck, North Dakota ($9541 [95% CI, $6382-$12 700]). The hospital referral regions with the highest mean spending on the amputation procedure itself were Paterson, New Jersey ($22 725 [95% CI, $12 859-$32 590]); Rapid City, South Dakota ($25 448 [95% CI, $3605-$47 292]); and Salinas, California ($30 039 [95% CI, $12 195-$47 884]).

Variation in the Proportion of All Costs Related to Revascularization

The proportion of all costs related to hospitalizations for revascularization, cellulitis, or debridement represented less than 10% of all costs in many regions, such as Pueblo, Colorado (7%); Grand Junction, Colorado (9%); and Redding, California (10%). However, revascularization and other procedural care represented more than 50% of all costs in Waterloo, Iowa (51%); Burlington, Vermont (52%); and Sun City, Arizona (53%). In 90 of the 307 hospital referral regions, more than 40% of spending in the year prior to amputation was attributable to revascularization, rather than wound care or the amputation procedure itself. There was a positive correlation between the proportion of patients treated with revascularization and the costs incurred in the year prior to amputation (R = 0.38, P < .001) (Figure 3).

Place holder to copy figure label and caption
Figure 3.
Scatterplot Depicting the Relationship Between Regional Spending Rates and Regional Revascularization Rates in the Year Prior to Amputation
Graphic Jump Location
Differences in Patient Characteristics, by Quintile of Spending

We examined differences in patient characteristics between high- and low-spending regions, across quintiles of spending (Table 1). In regions where spending was highest (mean spending of $27 395), patients undergoing an amputation were more likely to be African American (14% in very slow spending regions and 20% in very high spending regions) and were slightly more likely to have coronary artery disease (13% in very slow spending regions and 15% in very high spending regions). Charlson comorbidity scores were slightly higher in regions where spending was highest (3.0 in very slow spending regions and 3.6 in very high spending regions). As shown in Table 1, although many of these differences were statistically significant given our large sample, clinical differences in patients across quintiles of spending were small.

Use of Invasive Vascular Care, by Quintile of Spending

In regions with higher spending, patients were more likely to be treated with invasive vascular care. For example, patients in higher spending regions were more likely to undergo a vascular procedure, such as a diagnostic or therapeutic angiogram, or an open surgical procedure (12.0 procedures per 10 000 patients in the lowest quintile of spending and 20.4 procedures per 10 000 patients in the highest quintile of spending; P < .001) (Figure 4).

Place holder to copy figure label and caption
Figure 4.
Differences in Revascularization and Nonrevascularization Care, Across Quintile of Hospital Spending in the Year Prior to Amputation
Graphic Jump Location

Adjustment for age, sex, race, diabetes, cardiac, and renal disease across quintiles of spending on vascular care accentuated these differences. Overall, patients living in regions in the highest quintile of spending were more than 3 times as likely to undergo a vascular procedure compared with patients in regions in the lowest quintile of spending (adjusted odds ratio for receiving a vascular procedure, 3.5 [95% CI, 3.2-3.8]; P < .001) (Table 2). Similar trends were seen in both crude and adjusted analyses when individually examining open surgical revascularizations, therapeutic endovascular interventions, and diagnostic angiograms (crude rates are shown in Figure 4, and adjusted odds ratios are demonstrated in Table 2). We also found that regions where spending on vascular procedures was high also had high spending on the amputation procedure itself (R = 0.82, P < .001).

Table Graphic Jump LocationTable 2.  Multivariable Models Demonstrating the Likelihood of a Patient Undergoing Vascular Procedures, Across Quintiles of Spending, as Well as the Likelihood of Being in the Highest Quintile of the Amputation Rate
Correlation Between Spending and Amputation Rate, by Region

Despite the direct correlation between procedural care and overall spending, we did not find a direct relationship between overall spending in the year prior to amputation and regional amputation rate (R = 0.10, P = .06) (Figure 5). Even in risk-adjusted comparisons, there was no significant relationship between the likelihood of being in the highest quintile of the amputation rate and the overall spending rate (adjusted odds ratio, 0.95 [95% CI, 0.9-1.1]; P = .38) (Table 2).

Place holder to copy figure label and caption
Figure 5.
Scatterplot Depicting the Relationship Between Regional Spending Rates and Regional Amputation Rates
Graphic Jump Location

Across practice patterns, the regions that were most aggressive in the use of endovascular interventions (in the highest 20th percentile) were likely to have a high-spending rate (R = 0.42, P = .002) and a high amputation rate (R = 0.40, P = .004). Conversely, regions that were not aggressive in the use of endovascular interventions (in the lowest 20th percentile) were not likely to be in the highest quintile of the amputation rate (R = 0.10, P = .36).

In this descriptive analysis, we demonstrate that the costs of inpatient care in the year prior to amputation for patients with critical limb ischemia are more than $20 000 per patient for inpatient care alone. Furthermore, these costs vary more than 2-fold across hospital referral regions in the United States. Much of this variation is driven by differences in the use of revascularization treatments, rather than differences in patient characteristics or costs related to the amputation itself. Moreover, there is little evidence to suggest that higher spending on invasive vascular care, especially endovascular care, in the year prior to amputation is associated with lower regional rates of amputation.

An accurate measurement of the true cost of critical limb ischemia is difficult.2,16,17 Nonetheless, prior studies have examined the inpatient costs of vascular care. For example, the Reduction of Atherothrombosis for Continued Health (REACH) Registry investigators studied the 2-year costs of 25 763 patients with systemic atherosclerosis.18,19 For patients who underwent revascularization or amputation, the costs easily averaged more than $10 000 per patient during the 2 years following enrollment in the registry—a cost much higher than the cost for those patients with mild coronary disease. European patients enrolled in the REACH Registry also demonstrated high costs when they required revascularization or amputation, but the magnitude of these costs was much less than in the United States.20 Finally, investigators from Minnesota extrapolated costs from statewide data to estimate that vascular care in the United States exceeds several billion dollars annually.2 Therefore, although our study is limited to only patients in Medicare, it provides estimates that are consistent with prior work and provides national-level detail for each individual region of the United States.

In our study, some regions spent less than $13 000, on average, in the year prior to amputation, whereas other regions spent $30 000 or more in the year prior to amputation. Using these “natural experiments,” we found little evidence to suggest that the most expensive strategies are associated with better outcomes. Although we acknowledge the well-known weaknesses of administrative claims,21,22 the patients were roughly similar in many important demographic and comorbidity variables across strata of spending, and adjustment for any statistical differences had little impact on our findings. Therefore, it appears unlikely that these large differences in spending can be explained simply by differences in patient characteristics.

This suggests that an important opportunity exists, given the right kind of evidence, to save money while still providing high-quality care for patients with severe PAD. Although much of this necessary evidence will come from clinical trials,23,24 examination of the cost and effectiveness of these treatments in “real-world” settings will be important as well.3,9,25 National registries, such as the Society for Vascular Surgery's Vascular Quality Initiative,26 the National Surgical Quality Improvement Program,27 and the National Cardiovascular Data Registry,28 will need to incorporate the right end points. This means measuring both efficacy and cost to determine which strategies are effective in limiting amputation risk in patients with critical limb ischemia, in the most cost-effective manner.

Prior work by our group14 and others29,30 has suggested that more vascular care—as measured by any type of diagnostic or therapeutic vascular procedure in the year prior to amputation—is related to lower risks of amputation.14 Are these findings discordant with those reported herein? We believe not. Dramatic differences in cost can exist and are related to the manner in which patients with critical limb ischemia are treated. For example, patients treated with a plain old balloon angioplasty or a single surgical revascularization will incur much lower costs than patients receiving multiple rounds of atherectomy, drug-eluting balloons, or other more expensive endovascular adjuncts.3134 And, moreover, other strategies—such as primary amputation—may be the most cost-effective for patients with little chance of success with those kinds of treatment. Overall, however, our current analyses found that the highest spending rates—and the highest amputation rates—occurred in regions where multiple endovascular interventions were commonly used.

Different interpretations of the spending patterns described in our study are plausible as well. For example, one might argue that a region could provide high-quality preventive and invasive vascular care, and thereby prevent many patients from ever requiring amputation. Within a region like this, overall spending on vascular care would be high, and amputation rates would be low. However, we found few regions where spending and the overall intensity (measured by the number of procedures13) of vascular care were high and where the amputation rates were low. In fact, only 3 of 307 regions (Fort Lauderdale and Fort Myers, Florida, and Madison, Wisconsin) fit this description. Therefore, although plausible, this alternative explanation does not appear to represent an alternative explanation for our findings.

Our study has several important limitations. First, our work considered only inpatient costs and did not directly capture outpatient care. This outpatient care includes care that may be provided in wound care centers, outpatient angiography suites, and ambulatory imaging centers,3537 and complexities exist in differentiating and categorizing these different types of outpatient treatment centers. Even though the significant burden of comorbidities carried by patients with critical limb ischemia most commonly necessitates hospital-based care, vascular care is increasingly provided in outpatient settings.38,39 Our future work will consider not only hospital-based care but also care that is provided in ambulatory environments.

Second, our observational data set derives from administrative claims, and therefore it cannot provide patient-level clinical detail as to the extent of PAD or surgical-level specifics at the time of revascularization, such as the absolute number of patients in each region with any symptoms of PAD. However, our cohort was purposefully designed to consider only those patients with the most severe PAD, such that all patients studied had a limb-loss rate of 100%, an algorithm reflected in our prior publications.4,13,14 A further understanding of these mechanisms in patients who do not ultimately undergo amputation requires examination in clinically detailed cohorts, such as those from national registries. Third, because sidedness is not indicated on Medicare claims, we cannot be sure that revascularization procedures and amputations all occurred on the same limb. However, prior work by our group suggested that differential sides occur in fewer than 10% of procedures.40

Medicare spending on patients with severe PAD varies more than 2-fold across the United States, and the regions where spending is the highest perform the most revascularization procedures in the year prior to amputation. And although our prior work suggests that access to revascularization is a key component in preventing amputation, our current analysis offers little evidence to suggest that more expensive vascular care offers a marginal advantage over less expensive vascular interventions.14 In the current era of accountable care organizations, in which quality and cost must be equally considered,4143 saving money and preventing amputation appear to be 2 achievable and complementary goals.

Accepted for Publication: March 21, 2013.

Corresponding Author: Philip P. Goodney, MD, MS, Section of Vascular Surgery, Dartmouth-Hitchcock Medical Center, 1 Medical Center Dr, Lebanon, NH 03766 (philip.goodney@hitchcock.org).

Published Online: November 20, 2013. doi:10.1001/jamasurg.2013.4277.

Author Contributions: Dr Goodney had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Goodney, Goodman, Fisher, Birkmeyer.

Acquisition of data: Goodney, Travis.

Analysis and interpretation of data: Goodney, Brooke, DeMartino, Birkmeyer.

Drafting of the manuscript: Goodney, Birkmeyer.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Goodney, Travis, Brooke, Birkmeyer.

Obtained funding: Goodman, Fisher, Birkmeyer.

Administrative, technical, or material support: Goodney, Birkmeyer.

Study supervision: Goodney, DeMartino.

Conflict of Interest Disclosures: None reported.

Funding/Support: Dr Goodney was supported by a K-08 Career Development Award from the National Heart, Lung, and Blood Institute (grant 1K08HL05676-01) and an American Vascular Association/American College of Surgeons Supplemental Funding Award.

Role of the Sponsor: The funding agencies had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication.

Previous Presentation: This paper was presented at the Quality, Cost, and Outcomes Research Conference of the American Heart Association; May 9, 2012; Atlanta, Georgia.

Additional Contributions: We thank Jonathan S. Skinner, PhD, for his critiques and insights during the preparation of this work.

Peacock  JM, Keo  HH, Yu  X,  et al.  The incidence and health economic burden of critical limb ischemia and ischemic amputation in Minnesota: 2005-2007 [abstract 5788]. Circulation. 2009;120:S1148.
Peacock  JM, Keo  HH, Duval  S,  et al.  The incidence and health economic burden of ischemic amputation in Minnesota, 2005-2008. Prev Chronic Dis. 2011;8(6):A141.
PubMed
Goodney  PP, Beck  AW, Nagle  J, Welch  HG, Zwolak  RM.  National trends in lower extremity bypass surgery, endovascular interventions, and major amputations. J Vasc Surg. 2009;50(1):54-60.
PubMed   |  Link to Article
Holman  KH, Henke  PK, Dimick  JB, Birkmeyer  JD.  Racial disparities in the use of revascularization before leg amputation in Medicare patients. J Vasc Surg. 2011;54(2):420.e1-426.e1.
PubMed   |  Link to Article
Health Quality Ontario.  Stenting for peripheral artery disease of the lower extremities: an evidence-based analysis. Ont Health Technol Assess Ser. 2010;10(18):1-88.
PubMed
Cronenwett  JL, Likosky  DS, Russell  MT, Eldrup-Jorgensen  J, Stanley  AC, Nolan  BW; VSGNNE.  A regional registry for quality assurance and improvement: the Vascular Study Group of Northern New England (VSGNNE). J Vasc Surg. 2007;46(6):1093-1101; discussion 1101-1102.
PubMed   |  Link to Article
Nguyen  LL, Lipsitz  SR, Bandyk  DF,  et al.  Resource utilization in the treatment of critical limb ischemia: the effect of tissue loss, comorbidities, and graft-related events. J Vasc Surg. 2006;44(5):971-975, discussion 975-976.
PubMed   |  Link to Article
Siracuse  JJ, Giles  KA, Pomposelli  FB,  et al.  Results for primary bypass versus primary angioplasty/stent for intermittent claudication due to superficial femoral artery occlusive disease. J Vasc Surg. 2012;55(4):1001-1007.
PubMed   |  Link to Article
Goodney  PP, Nolan  BW, Schanzer  A,  et al; Vascular Study Group Of Northern New England.  Factors associated with death 1 year after lower extremity bypass in Northern New England. J Vasc Surg. 2010;51(1):71-78.
PubMed   |  Link to Article
Bradbury  AW, Adam  DJ, Bell  J,  et al; BASIL trial Participants.  Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL) trial: a description of the severity and extent of disease using the Bollinger angiogram scoring method and the TransAtlantic Inter-Society Consensus II classification [published correction appears in J Vasc Surg. 2010;52(6):1751]. J Vasc Surg. 2010;51(5 suppl):32S-42S.
PubMed   |  Link to Article
The Dartmouth Atlas of Health Care. http://www.dartmouthatlas.org. Accessed October 29, 2013.
CPT Editorial Panel—AMA/Specialty Society RVS Update Process. http://www.ama-assn.org/resources/doc/cpt/cpt-ruc-calendar.pdf. Accessed October 29, 2013.
Goodney  PP, Travis  LL, Nallamothu  BK,  et al.  Variation in the use of lower extremity vascular procedures for critical limb ischemia. Circ Cardiovasc Qual Outcomes. 2012;5(1):94-102.
PubMed   |  Link to Article
Goodney  PP, Holman  K, Henke  PK,  et al.  Regional intensity of vascular care and lower extremity amputation rates. J Vasc Surg. 2013;57(6):1471-1479, 1480.e1-3, discussion 1479-1480.
PubMed   |  Link to Article
Gottlieb  DJ, Zhou  W, Song  Y, Andrews  KG, Skinner  JS, Sutherland  JM.  Prices don’t drive regional Medicare spending variations. Health Aff (Millwood). 2010;29(3):537-543.
PubMed   |  Link to Article
Durham  CA, Mohr  MC, Parker  FM, Bogey  WM, Powell  CS, Stoner  MC.  The impact of socioeconomic factors on outcome and hospital costs associated with femoropopliteal revascularization. J Vasc Surg. 2010;52(3):600-606, discussion 606-607.
PubMed   |  Link to Article
Panayiotopoulos  YP, Tyrrell  MR, Owen  SE, Reidy  JF, Taylor  PR.  Outcome and cost analysis after femorocrural and femoropedal grafting for critical limb ischaemia. Br J Surg. 1997;84(2):207-212.
PubMed   |  Link to Article
Mahoney  EM, Wang  K, Keo  HH,  et al; Reduction of Atherothrombosis for Continued Health (REACH) Registry Investigators.  Vascular hospitalization rates and costs in patients with peripheral artery disease in the United States. Circ Cardiovasc Qual Outcomes. 2010;3(6):642-651.
PubMed   |  Link to Article
Mahoney  EM, Wang  K, Cohen  DJ,  et al; REACH Registry Investigators.  One-year costs in patients with a history of or at risk for atherothrombosis in the United States. Circ Cardiovasc Qual Outcomes. 2008;1(1):38-45.
PubMed   |  Link to Article
Smolderen  KG, Wang  K, de Pouvourville  G,  et al; REACH Registry Investigators.  Two-year vascular hospitalisation rates and associated costs in patients at risk of atherothrombosis in France and Germany: highest burden for peripheral arterial disease. Eur J Vasc Endovasc Surg. 2012;43(2):198-207.
PubMed   |  Link to Article
Mitchell  JB, Bubolz  T, Paul  JE,  et al.  Using Medicare claims for outcomes research. Med Care. 1994;32(7 suppl):JS38-JS51.
PubMed   |  Link to Article
Tseng  C-L, Rajan  M, Miller  DR,  et al.  Use of administrative data to risk adjust amputation rates in a national cohort of Medicare-enrolled veterans with diabetes. Med Care. 2005;43(1):88-92.
PubMed
Conte  MS, Bandyk  DF, Clowes  AW,  et al; PREVENT III Investigators.  Results of PREVENT III: a multicenter, randomized trial of edifoligide for the prevention of vein graft failure in lower extremity bypass surgery. J Vasc Surg. 2006;43(4):742-751, discussion 751.
PubMed   |  Link to Article
Adam  DJ, Beard  JD, Cleveland  T,  et al; BASIL trial participants.  Bypass versus angioplasty in severe ischaemia of the leg (BASIL): multicentre, randomised controlled trial. Lancet. 2005;366(9501):1925-1934.
PubMed   |  Link to Article
Goodney  PP, Nolan  BW, Schanzer  A,  et al; Vascular Study Group of Northern New England.  Factors associated with amputation or graft occlusion one year after lower extremity bypass in northern New England. Ann Vasc Surg. 2010;24(1):57-68.
PubMed   |  Link to Article
The Vascular Quality Initiative. Society for Vascular Surgery website. http://www.vascularqualityinitiative.org. Accessed October 29, 2013.
Khuri  SF, Daley  J, Henderson  W,  et al; National VA Surgical Quality Improvement Program.  The Department of Veterans Affairs’ NSQIP: the first national, validated, outcome-based, risk-adjusted, and peer-controlled program for the measurement and enhancement of the quality of surgical care. Ann Surg. 1998;228(4):491-507.
PubMed   |  Link to Article
Shaw  RE, Anderson  HV, Brindis  RG,  et al.  Development of a risk adjustment mortality model using the American College of Cardiology–National Cardiovascular Data Registry (ACC-NCDR) experience: 1998-2000. J Am Coll Cardiol. 2002;39(7):1104-1112.
PubMed   |  Link to Article
Holman  KH, Henke  PK, Dimick  JB, Birkmeyer  JD.  Racial disparities in the use of revascularization before leg amputation in Medicare patients. J Vasc Surg. 2011;54(2):420-426, 426.e1.
PubMed   |  Link to Article
Ho  V, Wirthlin  D, Yun  H, Allison  J.  Physician supply, treatment, and amputation rates for peripheral arterial disease. J Vasc Surg. 2005;42(1):81-87.
PubMed   |  Link to Article
Lumsden  AB, Davies  MG, Peden  EK.  Medical and endovascular management of critical limb ischemia. J Endovasc Ther. 2009;16(suppl 2):II31-II62.
PubMed
Bosiers  M, Deloose  K, Verbist  J, Peeters  P.  Update management below knee intervention. Minerva Cardioangiol. 2009;57(1):117-129.
PubMed
Rosales  OR, Mathewkutty  S, Gnaim  C.  Drug eluting stents for below the knee lesions in patients with critical limb ischemia: long-term follow-up. Catheter Cardiovasc Interv. 2008;72(1):112-115.
PubMed
Rogers  JH, Laird  JR.  Overview of new technologies for lower extremity revascularization. Circulation. 2007;116(18):2072-2085.
PubMed   |  Link to Article
Maurel  B, Paumier  A, Jacobi  D, Bleuet  F, Martinez  R, Lermusiaux  P.  Ambulatory percutaneous angioplasty in patients with claudication. Ann Vasc Surg. 2011;25(2):191-196.
PubMed   |  Link to Article
Egorova  NN, Guillerme  S, Gelijns  A,  et al.  An analysis of the outcomes of a decade of experience with lower extremity revascularization including limb salvage, lengths of stay, and safety. J Vasc Surg. 2010;51(4):878-885, 885.e1.
PubMed   |  Link to Article
Duijm  LE, van der Rijt  RH, Cuypers  PW,  et al.  Outpatient treatment of arterial inflow stenoses of dysfunctional hemodialysis access fistulas by retrograde venous access puncture and catheterization. J Vasc Surg. 2008;47(3):591-598.
PubMed   |  Link to Article
Samson  RH.  Setting up an outpatient imaging center: adding computed tomographic angiography, magnetic resonance angiography and an outpatient angiography suite to surgeon-run vascular laboratories. Perspect Vasc Surg Endovasc Ther. 2008;20(4):333-337.
PubMed   |  Link to Article
Burns  BJ, Phillips  AJ, Fox  A, Boardman  P, Phillips-Hughes  J.  The timing and frequency of complications after peripheral percutaneous transluminal angioplasty and iliac stenting: is a change from inpatient to outpatient therapy feasible? Cardiovasc Intervent Radiol. 2000;23(6):452-456.
PubMed   |  Link to Article
Tarry  WC, Walsh  DB, Birkmeyer  NJ, Fillinger  MF, Zwolak  RM, Cronenwett  JL.  Fate of the contralateral leg after infrainguinal bypass. J Vasc Surg. 1998;27(6):1039-1047; discussion 1047-1048.
PubMed   |  Link to Article
Goodney  PP, Fisher  ES, Cambria  RP.  Roles for specialty societies and vascular surgeons in accountable care organizations. J Vasc Surg. 2012;55(3):875-882.
PubMed   |  Link to Article
Fisher  ES, McClellan  MB, Bertko  J,  et al.  Fostering accountable health care: moving forward in Medicare. Health Aff (Millwood). 2009;28(2):w219-w231.
PubMed   |  Link to Article
Fisher  ES, Staiger  DO, Bynum  JP, Gottlieb  DJ.  Creating accountable care organizations: the extended hospital medical staff. Health Aff (Millwood). 2007;26(1):w44-w57.
PubMed   |  Link to Article

Figures

Place holder to copy figure label and caption
Figure 1.
Data on Patients, Procedures, and Hospitalization Cost From the Year Prior to Amputation in Our Cohort
Graphic Jump Location
Place holder to copy figure label and caption
Figure 2.
National Map (A) and Histogram (B) Demonstrating Regional Spending on Vascular Care and Hospitalizations in the Year Prior to Amputation, by Hospital Referral Region
Graphic Jump Location
Place holder to copy figure label and caption
Figure 3.
Scatterplot Depicting the Relationship Between Regional Spending Rates and Regional Revascularization Rates in the Year Prior to Amputation
Graphic Jump Location
Place holder to copy figure label and caption
Figure 4.
Differences in Revascularization and Nonrevascularization Care, Across Quintile of Hospital Spending in the Year Prior to Amputation
Graphic Jump Location
Place holder to copy figure label and caption
Figure 5.
Scatterplot Depicting the Relationship Between Regional Spending Rates and Regional Amputation Rates
Graphic Jump Location

Tables

Table Graphic Jump LocationTable 1.  Characteristics of Vascular Amputees in 2007-2009 Medicare Claims, by Quintile of Spending in Year Prior to Amputation on Revascularization/Hospitalization
Table Graphic Jump LocationTable 2.  Multivariable Models Demonstrating the Likelihood of a Patient Undergoing Vascular Procedures, Across Quintiles of Spending, as Well as the Likelihood of Being in the Highest Quintile of the Amputation Rate

References

Peacock  JM, Keo  HH, Yu  X,  et al.  The incidence and health economic burden of critical limb ischemia and ischemic amputation in Minnesota: 2005-2007 [abstract 5788]. Circulation. 2009;120:S1148.
Peacock  JM, Keo  HH, Duval  S,  et al.  The incidence and health economic burden of ischemic amputation in Minnesota, 2005-2008. Prev Chronic Dis. 2011;8(6):A141.
PubMed
Goodney  PP, Beck  AW, Nagle  J, Welch  HG, Zwolak  RM.  National trends in lower extremity bypass surgery, endovascular interventions, and major amputations. J Vasc Surg. 2009;50(1):54-60.
PubMed   |  Link to Article
Holman  KH, Henke  PK, Dimick  JB, Birkmeyer  JD.  Racial disparities in the use of revascularization before leg amputation in Medicare patients. J Vasc Surg. 2011;54(2):420.e1-426.e1.
PubMed   |  Link to Article
Health Quality Ontario.  Stenting for peripheral artery disease of the lower extremities: an evidence-based analysis. Ont Health Technol Assess Ser. 2010;10(18):1-88.
PubMed
Cronenwett  JL, Likosky  DS, Russell  MT, Eldrup-Jorgensen  J, Stanley  AC, Nolan  BW; VSGNNE.  A regional registry for quality assurance and improvement: the Vascular Study Group of Northern New England (VSGNNE). J Vasc Surg. 2007;46(6):1093-1101; discussion 1101-1102.
PubMed   |  Link to Article
Nguyen  LL, Lipsitz  SR, Bandyk  DF,  et al.  Resource utilization in the treatment of critical limb ischemia: the effect of tissue loss, comorbidities, and graft-related events. J Vasc Surg. 2006;44(5):971-975, discussion 975-976.
PubMed   |  Link to Article
Siracuse  JJ, Giles  KA, Pomposelli  FB,  et al.  Results for primary bypass versus primary angioplasty/stent for intermittent claudication due to superficial femoral artery occlusive disease. J Vasc Surg. 2012;55(4):1001-1007.
PubMed   |  Link to Article
Goodney  PP, Nolan  BW, Schanzer  A,  et al; Vascular Study Group Of Northern New England.  Factors associated with death 1 year after lower extremity bypass in Northern New England. J Vasc Surg. 2010;51(1):71-78.
PubMed   |  Link to Article
Bradbury  AW, Adam  DJ, Bell  J,  et al; BASIL trial Participants.  Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL) trial: a description of the severity and extent of disease using the Bollinger angiogram scoring method and the TransAtlantic Inter-Society Consensus II classification [published correction appears in J Vasc Surg. 2010;52(6):1751]. J Vasc Surg. 2010;51(5 suppl):32S-42S.
PubMed   |  Link to Article
The Dartmouth Atlas of Health Care. http://www.dartmouthatlas.org. Accessed October 29, 2013.
CPT Editorial Panel—AMA/Specialty Society RVS Update Process. http://www.ama-assn.org/resources/doc/cpt/cpt-ruc-calendar.pdf. Accessed October 29, 2013.
Goodney  PP, Travis  LL, Nallamothu  BK,  et al.  Variation in the use of lower extremity vascular procedures for critical limb ischemia. Circ Cardiovasc Qual Outcomes. 2012;5(1):94-102.
PubMed   |  Link to Article
Goodney  PP, Holman  K, Henke  PK,  et al.  Regional intensity of vascular care and lower extremity amputation rates. J Vasc Surg. 2013;57(6):1471-1479, 1480.e1-3, discussion 1479-1480.
PubMed   |  Link to Article
Gottlieb  DJ, Zhou  W, Song  Y, Andrews  KG, Skinner  JS, Sutherland  JM.  Prices don’t drive regional Medicare spending variations. Health Aff (Millwood). 2010;29(3):537-543.
PubMed   |  Link to Article
Durham  CA, Mohr  MC, Parker  FM, Bogey  WM, Powell  CS, Stoner  MC.  The impact of socioeconomic factors on outcome and hospital costs associated with femoropopliteal revascularization. J Vasc Surg. 2010;52(3):600-606, discussion 606-607.
PubMed   |  Link to Article
Panayiotopoulos  YP, Tyrrell  MR, Owen  SE, Reidy  JF, Taylor  PR.  Outcome and cost analysis after femorocrural and femoropedal grafting for critical limb ischaemia. Br J Surg. 1997;84(2):207-212.
PubMed   |  Link to Article
Mahoney  EM, Wang  K, Keo  HH,  et al; Reduction of Atherothrombosis for Continued Health (REACH) Registry Investigators.  Vascular hospitalization rates and costs in patients with peripheral artery disease in the United States. Circ Cardiovasc Qual Outcomes. 2010;3(6):642-651.
PubMed   |  Link to Article
Mahoney  EM, Wang  K, Cohen  DJ,  et al; REACH Registry Investigators.  One-year costs in patients with a history of or at risk for atherothrombosis in the United States. Circ Cardiovasc Qual Outcomes. 2008;1(1):38-45.
PubMed   |  Link to Article
Smolderen  KG, Wang  K, de Pouvourville  G,  et al; REACH Registry Investigators.  Two-year vascular hospitalisation rates and associated costs in patients at risk of atherothrombosis in France and Germany: highest burden for peripheral arterial disease. Eur J Vasc Endovasc Surg. 2012;43(2):198-207.
PubMed   |  Link to Article
Mitchell  JB, Bubolz  T, Paul  JE,  et al.  Using Medicare claims for outcomes research. Med Care. 1994;32(7 suppl):JS38-JS51.
PubMed   |  Link to Article
Tseng  C-L, Rajan  M, Miller  DR,  et al.  Use of administrative data to risk adjust amputation rates in a national cohort of Medicare-enrolled veterans with diabetes. Med Care. 2005;43(1):88-92.
PubMed
Conte  MS, Bandyk  DF, Clowes  AW,  et al; PREVENT III Investigators.  Results of PREVENT III: a multicenter, randomized trial of edifoligide for the prevention of vein graft failure in lower extremity bypass surgery. J Vasc Surg. 2006;43(4):742-751, discussion 751.
PubMed   |  Link to Article
Adam  DJ, Beard  JD, Cleveland  T,  et al; BASIL trial participants.  Bypass versus angioplasty in severe ischaemia of the leg (BASIL): multicentre, randomised controlled trial. Lancet. 2005;366(9501):1925-1934.
PubMed   |  Link to Article
Goodney  PP, Nolan  BW, Schanzer  A,  et al; Vascular Study Group of Northern New England.  Factors associated with amputation or graft occlusion one year after lower extremity bypass in northern New England. Ann Vasc Surg. 2010;24(1):57-68.
PubMed   |  Link to Article
The Vascular Quality Initiative. Society for Vascular Surgery website. http://www.vascularqualityinitiative.org. Accessed October 29, 2013.
Khuri  SF, Daley  J, Henderson  W,  et al; National VA Surgical Quality Improvement Program.  The Department of Veterans Affairs’ NSQIP: the first national, validated, outcome-based, risk-adjusted, and peer-controlled program for the measurement and enhancement of the quality of surgical care. Ann Surg. 1998;228(4):491-507.
PubMed   |  Link to Article
Shaw  RE, Anderson  HV, Brindis  RG,  et al.  Development of a risk adjustment mortality model using the American College of Cardiology–National Cardiovascular Data Registry (ACC-NCDR) experience: 1998-2000. J Am Coll Cardiol. 2002;39(7):1104-1112.
PubMed   |  Link to Article
Holman  KH, Henke  PK, Dimick  JB, Birkmeyer  JD.  Racial disparities in the use of revascularization before leg amputation in Medicare patients. J Vasc Surg. 2011;54(2):420-426, 426.e1.
PubMed   |  Link to Article
Ho  V, Wirthlin  D, Yun  H, Allison  J.  Physician supply, treatment, and amputation rates for peripheral arterial disease. J Vasc Surg. 2005;42(1):81-87.
PubMed   |  Link to Article
Lumsden  AB, Davies  MG, Peden  EK.  Medical and endovascular management of critical limb ischemia. J Endovasc Ther. 2009;16(suppl 2):II31-II62.
PubMed
Bosiers  M, Deloose  K, Verbist  J, Peeters  P.  Update management below knee intervention. Minerva Cardioangiol. 2009;57(1):117-129.
PubMed
Rosales  OR, Mathewkutty  S, Gnaim  C.  Drug eluting stents for below the knee lesions in patients with critical limb ischemia: long-term follow-up. Catheter Cardiovasc Interv. 2008;72(1):112-115.
PubMed
Rogers  JH, Laird  JR.  Overview of new technologies for lower extremity revascularization. Circulation. 2007;116(18):2072-2085.
PubMed   |  Link to Article
Maurel  B, Paumier  A, Jacobi  D, Bleuet  F, Martinez  R, Lermusiaux  P.  Ambulatory percutaneous angioplasty in patients with claudication. Ann Vasc Surg. 2011;25(2):191-196.
PubMed   |  Link to Article
Egorova  NN, Guillerme  S, Gelijns  A,  et al.  An analysis of the outcomes of a decade of experience with lower extremity revascularization including limb salvage, lengths of stay, and safety. J Vasc Surg. 2010;51(4):878-885, 885.e1.
PubMed   |  Link to Article
Duijm  LE, van der Rijt  RH, Cuypers  PW,  et al.  Outpatient treatment of arterial inflow stenoses of dysfunctional hemodialysis access fistulas by retrograde venous access puncture and catheterization. J Vasc Surg. 2008;47(3):591-598.
PubMed   |  Link to Article
Samson  RH.  Setting up an outpatient imaging center: adding computed tomographic angiography, magnetic resonance angiography and an outpatient angiography suite to surgeon-run vascular laboratories. Perspect Vasc Surg Endovasc Ther. 2008;20(4):333-337.
PubMed   |  Link to Article
Burns  BJ, Phillips  AJ, Fox  A, Boardman  P, Phillips-Hughes  J.  The timing and frequency of complications after peripheral percutaneous transluminal angioplasty and iliac stenting: is a change from inpatient to outpatient therapy feasible? Cardiovasc Intervent Radiol. 2000;23(6):452-456.
PubMed   |  Link to Article
Tarry  WC, Walsh  DB, Birkmeyer  NJ, Fillinger  MF, Zwolak  RM, Cronenwett  JL.  Fate of the contralateral leg after infrainguinal bypass. J Vasc Surg. 1998;27(6):1039-1047; discussion 1047-1048.
PubMed   |  Link to Article
Goodney  PP, Fisher  ES, Cambria  RP.  Roles for specialty societies and vascular surgeons in accountable care organizations. J Vasc Surg. 2012;55(3):875-882.
PubMed   |  Link to Article
Fisher  ES, McClellan  MB, Bertko  J,  et al.  Fostering accountable health care: moving forward in Medicare. Health Aff (Millwood). 2009;28(2):w219-w231.
PubMed   |  Link to Article
Fisher  ES, Staiger  DO, Bynum  JP, Gottlieb  DJ.  Creating accountable care organizations: the extended hospital medical staff. Health Aff (Millwood). 2007;26(1):w44-w57.
PubMed   |  Link to Article

Correspondence

CME


You need to register in order to view this quiz.
Submit a Comment

Multimedia

Supplement.

eAppendix. CPT and ICD-9 codes used to delineate the revascularization and amputation procedures in our cohort

Supplemental Content

Some tools below are only available to our subscribers or users with an online account.

1,790 Views
3 Citations

Related Content

Customize your page view by dragging & repositioning the boxes below.

Articles Related By Topic
Related Collections
PubMed Articles
Jobs
JAMAevidence.com

The Rational Clinical Examination: Evidence-Based Clinical Diagnosis
Quick Reference

The Rational Clinical Examination: Evidence-Based Clinical Diagnosis
Quick Reference

×