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Trends in the use of echocardiography, 2007 to 2011

Data Points #20

, PhD, MPH, , PhD, , PhD, , MPH, and , MPH.

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Echocardiography is a widely used procedure among the Medicare-enrolled population. Each year approximately 20% of enrollees in the fee-for-service (FFS) system receive at least one cardiac echocardiogram.

The percentage of enrollees who receive echocardiography services varies widely by geography. Use of echocardiography rises with age until age 85, where it plateaus.

Allowed health care charges for echocardiography decreased from 2007 through 2011 while the number of procedures rose slightly and the average number of procedures per beneficiary per year remained stable.

Heart disease is the leading cause of death for men and women in the United States.1 In 2010, heart disease caused more than one in four, or 27 percent, of deaths among individuals age 65 or older.1 Echocardiography is a noninvasive test that uses ultrasound waves to create pictures of the heart.2 An echocardiogram allows clinicians to see the structures of the heart and to see the motion of blood through the heart.3 It is often used by clinicians to assess, diagnose, and manage heart problems such as abnormal valves, atrial fibrillation, heart disease, heart murmurs, and other issues.2, 3

Use of echocardiography increased dramatically in the United States from the 1990s to early 2000s. This increase occurred at a higher rate than non-cardiac imaging services, and was greater than might be expected relative to the aging of the population.4,5 Between 2000 and 2010, the volume of imaging services increased by 81 percent within Medicare.6 Also by 2010, echocardiography services made up 11 percent of Medicare spending on imaging services, accounting for approximately $1.2 billion in spending.6 The growth in use of echocardiography may have slowed in the late 2000s, but it remains an often used procedure.7,8

Efforts have been made to slow the increase in use of echocardiography through both payment and practice. The Deficit Reduction Act of 2005 reduced the Medicare payment for the technical com-ponent of echocardiography.9-11 In 2007, the Centers for Medicare & Medicaid Services (CMS) further reduced the amount paid for procedures beyond the index procedure on contiguous body parts during the same session.9 To address the possible overuse of echocardiography due to patterns of health care practice, a task force led by the American College of Cardiology Foundation (ACCF), American Society of Echocardiography (ASE), and specialty and subspecialty societies set out criteria for the appropriate use of echocardiography.12

They concluded that “appropriate echocardiograms are those that are likely to contribute to improving patients' clinical outcomes, and importantly, inappropriate use of echocardiography may be potentially harmful to patients and generate unwarranted costs to the health care system.”12 The criteria vary by previous service and clinical indication, but in general echocardiography testing is viewed as appropriate to assess conditions that have an indication of being cardiac in nature or to reassess diagnosed cardiac conditions when patients' symptoms have changed. Retesting to monitor a condition is considered inappropriate when patients' symptoms have not changed, there is no planned change in clinical management, and/or when fewer than one to three years have passed since the initial echocardiogram.12 One study estimates that the Deficit Reduction Act and the implementation of appropriateness criteria are two of multiple factors that have slowed the growth of echocardiography since 2005.8 However, the effect of these initiatives has not yet been quantified.

Understanding trends in the use of echocardiography remains complex (see Figures 1-3). It appears that the growth may be due to primary care providers who are increasingly ordering echocardiograms using equipment in their own offices rather than an increase in use by specialty providers such as cardiologists.6 The presence of testing equipment for echocardiography in primary care offices has been hypothesized to be a possible driver of this increase in use by primary care physicians. This relationship is still unclear - in the case of stress echocardiography, the relationship between the office location of testing material and increased cost of care after testing is modest.13 However, evidence indicates that physicians of various specialties tend to increase their use of tests when they are able to self-refer.14

Line graph showing the number of echocardiography services performed annually in Medicare. About 6.8 million echocardiography services were performed in 2007, increasing to about 7.1 million in 2011.

Figure 1

Echocardiography services performed annually for the Medicare fee-for-service program, 2007-2011.

Bar chart showing the percentage of eligible Medicare beneficiaries receiving one or more echocardiography service by age category in 2011. The figure shows that the percent of beneficiaries receiving echocardiography services increases steadily from 13% in the 65-69 group to 26% in the 80-84 group, and plateaus at about 25% in the 85+ age group.

Figure 3

Eligible Medicare beneficiaries receiving one or more echocardiography service, by age, 2011.

There is significant geographic variation in the use of echocardiography. Rates of echocardiography and noninvasive diagnostic imaging are lower in the Northern U.S. and higher in the Southeastern U.S.15, 16 Use of echocardiography is higher in urban areas than for patients in rural areas. This may be due to greater distance for those in rural areas to facilities offering echocardiography, suggesting that greater patient volume may be associated with the decision to invest in echocardiography equipment.16-18 Variations in the prevalence of heart disease also appear to contribute to geographic variations in use of echocardiography.6 Among patients who receive echocardiography tests, most receive approximately one test a year.7, 18 Patients living in higher population areas are more likely to have a test repeated.18

This report examines trends in echocardiography between 2007 and 2011. For these years, we describe trends in echocar-diography services (see Table 1 for service codes) by numbers of services performed, place of service, and population characteristics. We also describe geographic variation in use of echocardiography. We would like to acknowledge the leadership of the DEcIDE Cardiovascular Consortium in establishing the scope and objectives of this report.

Table 1. Echocardiography service category codes.

Table 1

Echocardiography service category codes.

METHODS

The analysis was performed using Medicare enrollment data and 100 percent fee-for-service (FFS) Parts A and B institutional/noninstitutional claims data for years 2007 through 2011. The source of the claims and enrollment data was the CMS Chronic Conditions Warehouse (CCW).

We identified Medicare beneficiaries age 65 or older who had Part A and Part B Medicare coverage with no Medicare Advantage (i.e., managed care enrollment) during their period of eligibility and who received echocardiography services during the reference year. Receipt of service was identified by Berenson-Eggers type of service (BETOS) code I3C, excluding Health Care Common Procedure Coding System (HCPCS) code 93299, and including HCPCS codes 93350 and 93662.19 Multiple procedures for the same beneficiary in a day were coded as a single event.

We assessed trends in procedures across years and demographic factors, including age and gender (identified in the beneficiary summary file during the year the procedure took place), as well as race/ethnicity, region, and urbanicity as defined below (see Table 2).

Table 2. Distribution of echocardiography services by population characteristics, 2011.

Table 2

Distribution of echocardiography services by population characteristics, 2011.

Beneficiary demographic and geographic characteristics

Race/ethnicity: Race and ethnicity were defined using the Research Triangle Institute Race Code, which applies a surname algorithm to assign Hispanic ethnicity.20, 21

Age: The age categories were defined using the age of the beneficiary at the end of each reference year.

Urban/Rural: We used the Core Based Statistical Area (CBSA) of the beneficiary to identify the urban region in which the beneficiary resides. Beneficiaries who do not reside in a CBSA are considered to be rural.22

Dual Status: CMS has an established algorithm for defining the annual dual eligibility status of each beneficiary using the monthly State Reported Dual Eligibility Status Codes.

The algorithm categorizes beneficiaries into four groups: Full Duals had full Medicare and Medicaid coverage (including prescription drugs) during the most recent month of dual eligibility for the reference year; QMB beneficiaries had Medicaid and participated in the Qualified Medicare Beneficiary Program during the most recent month of dual eligibility for the reference year; Other/Partial Duals had Medicaid and participated in the Specified Low-Income Medicare Beneficiary Program during the most recent month of dual eligibility for the reference year, the Qualifying Individual Program, or the Qualified Disabled and Working Individuals Program; and Nonduals had Medicare coverage only for the reference year.23

Costs of echocardiography services were computed as Medicare allowed costs, which include the costs paid by Medicare and the beneficiary contribution, coinsurance, and deductible. Costs were split into several service categories defined below.

Service categories

Base, Add-on, and Associated Services: Service category codes and definitions are displayed in Table 1.

Physician Specialty: Part B institutional echocardiography services were classified Outpatient Facility specialty services.

For Part B noninstitutional echocardiography services, the specialty of the physician is identified on the service line item of the claim using HCFA specialty code. We classified the specialty as follows: Cardiology = 06; Internal Medicine = 11; General/family practice = 01 or 08; Diag-nostic Radiology = 30; Independent diagnostic testing facility = 47; and other for any other designation. Multiple physician specialties could be included for each echocardiography service.

Place of Service: The place of service is Outpatient and ER for Part B institutional echocardiography services. For Part B noninstitutional echocardiography services, the place of service is identified on the service line item of the claim using HCFA place of service code.

We classified the place of service as follows: Inpatient = 21; Outpatient and ER = 22 or 23; Office and Independent Diagnostic Testing Facility (IDTF) = 11, or if physician specialty = 47; and other for any other designation.24 Only one place of service is included per echocardiography service.

Although we examined data from 2007 to 2011, results from 2011 only are presented in the main body of this report. Results for earlier years appear in the Appendixes.

RESULTS

From 2007 through 2011, approximately 34 million echocardiography procedures were performed on Medicare beneficiaries. The number of beneficiaries receiving echocardiography procedures was relatively constant between 6.8 million in 2007 and 7 million in 2011 (Figure 1). Of all Medicare beneficiaries, about 20 percent received an echocardiography service in 2011 (Figure 2). This proportion remained fairly constant, increasing only slightly between 2007 and 2011 (from 19.7% in 2007 to 20.1% in 2011).

Line graph of the percentage of eligible Medicare beneficiaries receiving one or more echocardiography service by age category. Beneficiaries age 80 and above have the highest percentage receiving echocardiography services at around 25%, while beneficiaries ages 65-69 have the lowest percentage at around 14% of beneficiaries receiving echocardiography services.

Figure 2

Eligible Medicare beneficiaries receiving one or more echocardiography services, by age, 2007-2011.

The proportion of beneficiaries receiving echocardiography services varied with age, increasing between ages 65 and 84 from 13.4 percent to 25.7 percent, and decreasing slightly at age 85 and older to 25.1 percent in 2011 (Figure 3).

In 2011, non-Hispanic White and Hispanic populations both received echocardiography services at a rate of about 20 percent (20.0% and 20.4%, respectively). Among African Americans the rate was slightly higher at about 21.9 percent, and Asians/Pacific Islander and American Indians/Alaska Natives had lower rates at 18.8 percent and 16.4 percent, respectively (Table 2).

Females received echocardiography services at a lower rate than males (19.4% versus 21.0%). Full dual beneficiaries received a higher proportion of services (23.9%) than nonduals (19.7%), partial duals (22.6%), and QMBs (22.8%; Table 2).

The rates of echocardiography services received vary by State. In 2011, New York and New Jersey had the highest proportion of beneficiaries receiving echocardiography at 27.3 percent and 26.5 percent, followed by Florida at 25.2 percent (Figure 4A). Idaho and Alaska had the lowest proportion at 12.7 percent and 13.1 percent. Geographic patterns are largely similar across states for urban and rural areas (Figures 4B-4C). Urban beneficiaries received echocardiography services at a higher rate (20.4%) than rural beneficiaries (17.2%, Table 2).

Map shows that New York, New Jersey, and Florida have the highest percentage (25-30%) of beneficiaries receiving echocardiography services. The South and Northeast have higher rates of echocardiography use than the Western States.

Figure 4A

Eligible beneficiaries receiving echocardiography services, by State, 2011.

Map shows that there is variation in the percentage of eligible rural beneficiaries receiving echocardiography services by state, with the highest percentages in the Northeast and Southeast and lowest percentages in the Western states.

Figure 4B

Eligible rural beneficiaries receiving echocardiography services, by State, 2011. *Delaware excluded due to cell size of <11. Values for Hawaii and Rhode Island are not shown due to lack of rural population as coded in this analysis. Full data (more...)

Map shows that there is variation in the percentage of eligible urban beneficiaries receiving echocardiography services by state, with the highest percentages in the Northeast and Southeast and lowest percentages in the Western states.

Figure 4C

Eligible urban beneficiaries receiving echocardiography services, by State, 2011.

Among Medicare beneficiaries who received echocardiography services in 2011, the average number of echocardiograms per person per year was 1.3 (Table 3). Most beneficiaries who received echocardiography services had one service a year.

Table 3. Echocardiography services among beneficiaries who received at least one echocardiography service by population characteristics, 2011.

Table 3

Echocardiography services among beneficiaries who received at least one echocardiography service by population characteristics, 2011.

In 2011, 80.2 percent received only one service a year, 14.7 percent had two services, 3.4 percent had three services, 1.0 percent had four services, and only 0.7 percent had five or more services a year (Figure 5). This distribution of services was fairly constant between 2007 and 2011. There was a small increase in the percentage of beneficiaries receiving four and five or more services (from 0.9% in 2007 to 1.0% in 2011 for four services, and from 0.6% in 2007 to 0.7% in 2011 for five or more services).

Figure showing the percent of Medicare beneficiaries receiving 1 or more echocardiography services in 2011. 80% of beneficiaries receiving an echocardiography service had only 1 service, 15% had 2, 3% had 3, 1% had 4, and 1% had 5 or more echocardiography services.

Figure 5

Eligible beneficiaries receiving echocardiography services, by number of services received, 2011.

Among racial and ethnic groups, African Americans, Hispanics, and American Indians/Alaska Natives were slightly more likely to receive two or more echocardiography services a year than non-Hispanic Whites and Asians/Pacific Islanders in 2011 (Table 3).

Females were more likely to have only one echocardiogram per year than males, with 81.1 percent of females receiving only one service while 79.1 percent of males received one service.

Full duals were more likely to have two or more echocardiography services than nonduals, partial duals, and QMBs (Table 3).

Across the different service settings where echocardiography was performed, the inpatient setting had the highest mean number of services (1.3 per beneficiary per year), followed by outpatient and emergency room (1.1), office and independent diagnostic testing facility (1.1), and all other settings (1.1; Appendix G).

Total allowed health care charges for echocardiography were $1.6 billion in 2011, a decrease from $1.85 billion in 2007 (Figure 6). Of practice specialties that performed echocardiography, cardiology had the highest allowed charges overall. However, the charges within cardiology decreased over time, from $1.14 billion in 2007 to $839 million in 2011 (Figure 6, Appendix H). Allowed charges in other specialties also decreased over time, with the exception of those for outpatient facilities, which increased from $404 million in 2007 to $604 million in 2011 (Figure 6, Appendix H).

Figure showing total allowed charges for echocardiography by type of health care provider completing the service from 2007-2011. Total allowed charges were at about $1.8 billion in 2007, decreasing to $1.6 billion in 2011. Cardiology has the highest allowed charges, at about $1.2 billion in 2007 decreasing to about $0.8 billion in 2011. Charges in outpatient facility increased from about $0.4 billion in 2007 to $0.6 billion in 2011.

Figure 6

Total allowed charges for echocardiography by type of health care provider, 2007-2011. IDTF = Independent Diagnostic Testing Facility.

DISCUSSION

Echocardiography is a widely used service within the Medicare program. Each year approximately 20 percent of beneficiaries in the fee-for-service (FFS) Medicare program received at least one procedure. Of this group, 20 to 30 percent received more than one echocardiography service.

While a variety of efforts were undertaken in an attempt to control rising costs for cardiac echocardiograms, their success was modest at best. Total allowed charges decreased from 2007 through 2011, while the number of procedures rose slightly and the average number of procedures per beneficiary per year remained essentially unchanged. Findings indicated a very small decrease in the percentage of beneficiaries receiving echo procedures from 2009-2010 (20.4%) to 2011 (20.1%, Appendix K), but among those receiving services, the number of services received generally slightly increased. This suggests that, to date, changes in payments are not reducing use of the procedure.

This analysis identifies two dramatic trends. First, among age groups, the use of echocardiography rose steeply until age 85, when it plateaued. This pattern suggests that use of echocardiography will continue to rise given the aging of the Medicare population.

Second, tremendous geographic variation continues to exist in use of echocardiography. As shown in Figures 4A-4C and Appendices A-F, I, and L, State-to-State variability in echocardiography use was large, and is unlikely to be explained by differences in payment policy alone. Whether measures of health care resources such as cardiologists or echocardiography facilities explain these patterns exceeds the scope of this report. Such questions deserve further exploration.

Further variations were evident among other characteristics, including by urbanicity, reinforcing earlier findings regarding lower rates of use among rural beneficiaries. Variations in use within racial/ethnic groups also exist but appear to be stable over the period 2007-2011. Further work is needed to establish the degree to which these patterns represent intersections in health care access, groupwide differences in health status, or varying propensity for use or recommendation of use in these populations.

Over the study period, the Medicare population increased more quickly in some racial/ethnic subgroups than others. Even if the percentage of Medicare beneficiaries receiving echocardiography services remains stable over time, population increases in these subgroups within Medicare may affect the total number of echocardiography services performed. This implies that efforts to decrease echocardiography use will not just need to be sensitive to overall population trends, but also take into account trends in use in racial/ethnic subgroups within the Medicare population.

This report includes some limitations. First, we only counted one procedure per day. Thus, we may have slightly under-counted the total number of procedures if a significant number of beneficiaries had two or more procedures on the same day. However, these procedures would be captured in total allowed charges.

Second, claims data do not contain information about the indication for the procedure nor of the test result or action that may have been guided by the procedure. Thus, we cannot quantify whether the echocardiography use resulted in important information that was used to direct clinical care.

Third, we present unadjusted numbers only and do not conduct statistical testing of differences in proportions. Because our sample includes the entire Medicare FFS population for all study years, we are able to conduct analyses on the full population of interest rather than a sample. Statistical inference is needed only when evaluating the potential error of the sample, and thus is not necessary in this situation.25 In addition, calculations of standard errors and standard statistical tests commonly incorporate sample size. With the large size of the full Medicare FFS population, it is likely that even small, unimportant trends would be measured as being statistically different.26 Therefore, we chose to omit statistical testing and leave conclusions about the importance of patterns to the reader. In spite of these limitations, we believe that the results of this inquiry provide important insights about the use of echocardiography over time and across geographic and demographic groups.

CONCLUSION

Echocardiography is a widely used procedure among the Medicare-enrolled population. Each year approximately 20 percent of enrollees in the FFS system receive at least one cardiac echocardiogram. There is sizable geographic variation in use of echocardiography that deserves investigation. Recent changes in reimbursement policy appear to have reduced total allowed charges but have not led to shifts in the percentage of enrollees receiving services nor in the average number of echocardiography services per recipient.

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Acknowledgments

The authors wish to thank the DEcIDE Cardiovascular Consortium for their leadership in establishing the scope and objectives of this report.

This project was funded under Contract No. HH-SA29020100013I from the Agency for Healthcare Research and Quality, U.S. Department of Health and Human Services as part of the Developing Evidence to Inform Decisions about Effectiveness (DEcIDE) program. The authors of this report are responsible for its content. Statements in the report should not be construed as endorsement by the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services. This project has been approved by the University of Minnesota Institutional Review Board.

Suggested Citation: Virnig BA, Shippee ND, O'Donnell B, Zeglin J, Parashuram S.Trends in the Use of Echocardiography, 2007 to 2011. Echocardiography Trends. Data Points #20 (prepared by the University of Minnesota DEcIDE Center, under Contract No. HHSA29020100013I ). Rockville, MD: Agency for Healthcare Research and Quality; May 2014. AHRQ Publication No. 14-EHC034-EF.

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