The Committee was asked to consider, in addition to the possible benefits, the cost to the Medicare program of coverage of thyroid stimulating hormone (TSH) screening. This cost is dependent on the number of people screened and changes in the use of resources that result from screening. This chapter begins with an examination of the effect that Medicare coverage has had on the use of other preventive services and identifies factors from that experience that may be relevant to screening with TSH for thyroid dysfunction. The impact of these factors is assessed in conjunction with additional data from a study of thyroid disease among Medicare beneficiaries and an analysis of Medicare claims data to provide estimates of the number of beneficiaries who would be screened. Finally, an economic model is used to estimate costs per beneficiary screened.
There are limited historical data that can be used to ascertain how much of an effect Medicare coverage of various preventive services has had on the use of those services. The Centers for Disease Control and Prevention tracks use of preventive services through its Behavioral Risk Factor Surveillance System (BRFSS) (Centers for Disease Control and Prevention, 2002). After these services are covered, their use also can be tracked through the use of Medicare claims data (McBean, 2002). Tables 5-1A through 5-1C show the BRFSS data for influenza and pneumonia immunizations, mammography, and Pap smears, the only preventive services covered by Medicare for which BRFSS data are available.
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5
The Cost of Coverage
The Committee was asked to consider, in addition to the possible benefits, the cost to the Medicare program of coverage of thyroid stimulating hormone (TSH) screening. This cost is dependent on the number of people screened and changes in the use of resources that result from screening. This chapter begins with an examination of the effect that Medicare coverage has had on the use of other preventive services and identifies factors from that experience that may be relevant to screening with TSH for thyroid dysfunction. The impact of these factors is assessed in conjunction with additional data from a study of thyroid disease among Medicare beneficiaries and an analysis of Medicare claims data to provide estimates of the number of beneficiaries who would be screened. Finally, an economic model is used to estimate costs per beneficiary screened.
COVERAGE AND USE OF PREVENTIVE SERVICES
There are limited historical data that can be used to ascertain how much of an effect Medicare coverage of various preventive services has had on the use of those services. The Centers for Disease Control and Prevention tracks use of preventive services through its Behavioral Risk Factor Surveillance System (BRFSS) (Centers for Disease Control and Prevention, 2002). After these services are covered, their use also can be tracked through the use of Medicare claims data (McBean, 2002). Tables 5-1A through 5-1C show the BRFSS data for influenza and pneumonia immunizations, mammography, and Pap smears, the only preventive services covered by Medicare for which BRFSS data are available.
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TABLE 5-1A Use of Preventive Services Covered by Medicare: Pneumonia and Influenza Immunizations
Year
Pneumonia Shot Ever (Age 65+)a
Flu Shot Within 12 Months (Age 65+)b
1993
27.8%
50.9%
1995
38.4%
60.0%
1997
45.7%
65.9%
1999
54.9%
67.4%
2001
61.3%
66.2%
aFirst year of Medicare coverage -1981
bFirst year of Medicare coverage -1993
SOURCE: Centers for Disease Control and Prevention, 2001
TABLE 5-1B Use of Preventive Services Covered by Medicare: Mammography and Breast Examination
Mammogram & Breast Exam Ever
Within 2 Years
Year
Age 50-64
Age 65+
Age 50-64
Age 65+
1990
70.4%
58.9%
63.8%
54.3%
1991a
74.2%
64.8%
67.0%
58.0%
1992
75.0%
66.2%
67.7%
60.7%
1993
78.8%
71.0%
70.6%
64.5%
1994
79.5%
71.3%
71.9%
65.4%
1995
82.6%
72.6%
74.5%
65.8%
1996
83.9%
75.3%
76.1%
67.2%
1997
85.0%
76.8%
76.9%
70.0%
1998b
85.2%
75.6%
77.6%
72.4%
1999
86.1%
78.6%
79.1%
73.3%
2000
87.8%
79.3%
81.2%
77.1%
aFirst year of Medicare coverage
bAnnual mammography covered
SOURCE: Centers for Disease Control and Prevention, 2001
Coverage for preventive services has been accompanied by only gradual increases in the use of those services. In the case of pneumococcal vaccine, for example, by 1993 only 27.8 percent of the population age 65 and older reported that they had ever been immunized even though Medicare has covered the service since 1981. This proportion then nearly doubled between 1993 and 1999 and has continued to increase. The U.S. General Accounting Office (GAO) has found that Medicare coverage by itself has not been enough to promote use of preventive services by most beneficiaries, and additional efforts—working to increase demand or remove other barriers to access to services—are necessary to increase their use (GAO, 2002). A large body of work on theories and behavioral models
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TABLE 5-1C Use of Preventive Services Covered by Medicare: Pap Smears
Pap Smear Within 3 Years
Yeara
Age 50-64
Age 65+
1992
82.6%
67.6%
1993
81.9%
70.1%
1994
82.4%
69.9%
1995
83.1%
70.1%
1996
84.6%
69.3%
1997
84.9%
71.2%
1998b
84.6%
68.9%
1999
85.3%
72.3%
2000
87.5%
74.5%
aFirst year of Medicare coverage - 1990
bPelvic Examinations covered
SOURCE: Centers for Disease Control and Prevention, 2001
has addressed the question of determinants of utilization of clinical preventive interventions in primary care (Elder et al., 1999).
Demand is a key factor in service use. If there is little interest in or awareness of the service by the patient (or the patient’s physician), coverage will make little difference. This appears to have been the case for pneumococcal vaccine—significant educational and outreach programs were used to increase immunization rates (GAO, 2002). The close correlation between the usage of services in the population over age 65 and in younger age ranges suggests that demand for preventive services by Medicare beneficiaries parallels more general trends in society.
Medicare coverage may be an important factor in the use of a service, but the effect is indirect. Strictly speaking, Medicare coverage policy only assures that Medicare payment for a particular service is available. A cost barrier is removed for those Medicare beneficiaries for whom the cost of the test would be a barrier to its use. If these beneficiaries encounter barriers in addition to the cost of the service, payment will not enable them to make use of the service unless those barriers are also overcome. The primary economic barrier to the use of preventive services may not be the cost of the service but the costs of other activities related to obtaining the service.
Access to health care services is also heavily influenced by factors that are not related or only indirectly related to payment for services. For example, significant differences exist in the use of Medicare-covered preventive services among racial and ethnic groups (GAO, 2002); these differences are partially
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related to the degree of trust held in providers and the health care system (IOM, 2002). In some states, the lack of easily available Medicare providers has limited the use of preventive services (GAO, 2002). The problem of availability of providers may be geographical remoteness in rural areas or may be a reflection of the lack of material resources in communities too poor to provide adequate health care facilities. Factors with important positive influence on access to care include social support networks that encourage patients to seek care and support; the ability of patients to leave home or work to obtain care; well-developed transportation systems; low crime rates; high literacy rates; providers with compatible language and culture; and a regular provider and site of care (IOM, 2002). Even when patients have good access to health care services, the delivery system may need to be changed so that preventive services can be easily offered, accepted, and delivered within the usual patterns of care (GAO, 2002).
Finally, coverage may not have a significant impact on the use of a service if the service is easily available without coverage. If it is not expensive, a patient may pay for the service himself. A number of “Medigap” supplemental insurance plans cover preventive services. Providers are often motivated to offer free screening as a means of identifying new patients in need of services for which the providers would be paid. Some screening tests are also used for diagnostic purposes, and the line between screening and diagnosis can often be blurred (McBean, 2002). If good alternative means exist for obtaining the service, a beneficiary may not take advantage of coverage or may substitute for the alternative by obtaining the service through Medicare coverage.
ESTIMATING DEMAND FOR TSH SCREENING
There is no direct evidence, such as surveys or pilot programs, of the level of interest or demand for serum TSH screening among Medicare beneficiaries or health care practitioners. Statements of expert opinion have been made on screening for thyroid disease, and a number of groups have published recommendations on the subject (Arbelle and Porath, 1999; United States Preventive Services Task Force, 1996), but their conclusions have differed. Even without such disagreements, the acceptance of recommendations into common practice is a long and complex process (IOM, 1990).
To estimate the use of serum TSH screening with Medicare coverage, the Committee needed two types of information: the size of the population covered and the proportion of the potential screening population likely to be tested. Creation of a preventive services benefit for TSH screening should only affect directly those Medicare beneficiaries who do not already have an indication for testing. To estimate the size of the potential screening population, it is necessary to count only those beneficiaries who would not already be covered for serum TSH testing under current Medicare coverage policy. That group would include not just beneficiaries with known thyroid disease but also those with conditions
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believed to be affected by thyroid disease. The proportion of beneficiaries who receive serum TSH tests among those who are without known thyroid disease but currently covered for serum TSH testing could provide a plausible estimate of the proportion tested out of the potential screening population.
Current Medicare Coverage Policy
On November 23, 2001, the Federal Register published a Medicare National Coverage Decision for thyroid testing (Centers for Medicare and Medicaid Services, 2001). According to this document (page 58853);
Thyroid function tests are used to define hyperfunction, euthyroidism, or hypofunction of thyroid disease. Thyroid testing may be reasonable and necessary to:
Distinguish between primary and secondary hypothyroidism;
Confirm or rule out primary hypothyroidism;
Monitor thyroid hormone levels (for example, patients with goiter, thyroid nodules, or thyroid cancer);
Monitor drug therapy in patients with primary hypothyroidism;
Confirm or rule out primary hyperthyroidism; and
Monitor therapy in patients with hyperthyroidism.
Thyroid function testing may be medically necessary in patients with disease or neoplasm of the thyroid and other endocrine glands. Thyroid function testing may also be medically necessary in patients with metabolic disorders; malnutrition; hyperlipidemia; certain types of anemia; psychosis and nonpsychotic personality disorders; unexplained depression; ophthalmologic disorders; various cardiac arrhythmias; disorders of menstruation; skin conditions; myalgias; and a wide array of signs and symptoms, including alterations in consciousness; malaise; hypothermia; symptoms of the nervous and musculoskeletal system; skin and integumentary system; nutrition and metabolism; cardiovascular; and gastrointestinal system. It may be medically necessary to do follow-up thyroid testing in patients with a personal history of malignant neoplasm of the endocrine system and in patients on long-term thyroid drug therapy.
This is a very broad range of clinical conditions. The document lists approximately 200 ICD-9-CM codes for diagnoses that would establish medical necessity for TSH testing. (These are listed in Appendix C.) Although many of these diagnoses are obscure, a large number describe conditions that are common in the Medicare population, including diabetes, hypertension, hyperlipidemia, anemia, dementia, cardiac arrhythmias, palpitations, insomnia, fatigue, weight change, and constipation. This would indicate that many Medicare beneficiaries already have an indication for TSH testing and, therefore, should be unaffected by coverage of TSH screening as a preventive services benefit.
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Identifying the Target Population
The Committee used two sources of data to identify which Medicare beneficiaries in the population do not already have an indication for TSH testing. The first was the New Mexico Elder Health Survey, a population-based sample of Medicare beneficiaries in Bernalillo County (Albuquerque), New Mexico (Lindeman et al., 1999). The second was an analysis of Medicare claims data.
The New Mexico Elder Study
The New Mexico Elder Study used Medicare enrollment data to select and recruit 883 Medicare beneficiaries for an interview and examination, including TSH and other diagnostic tests. Nearly half of this group was Hispanic, a proportion much larger than the national Medicare population, which is less than 3 percent Hispanic (U.S. Department of Health and Human Services, 1998); none were African American. Because the prevalence of some common conditions that are indications for TSH testing, particularly diabetes, is significantly different in the Hispanic population than in the general Medicare population, we analyzed the 469 non-Hispanic subjects (non-Hispanic whites are about 85 percent of the national Medicare population) (U.S. Department of Health and Human Services, 1998) separately from the 414 Hispanic subjects.
We estimated the number of subjects who did not have an indication for TSH testing under current Medicare coverage policy by removing from the sample those who appeared to have an indication for testing:
Known thyroid disease: A history of thyroid disease or current thyroid medication use
Hypertension: Systolic blood pressure above 160 mmHg, self-reported hypertension, or current antihypertension medication
Current fatigue
Weight gain or loss of more than 10 pounds in the past 6 months
Hyperlipidemia: Serum cholesterol greater than 240mg/dl
Insomnia
Current hoarseness
Arrhythmia on electrocardiogram or physical examination
History of depression
Anemia: Men with a hematocrit below 40,women with a hematocrit below 35
Diabetes: Current diabetes medication or history of diabetes
Current neurological problem
Current chronic constipation
Current tranquilizer use as evidence of anxiety or insomnia
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After these subjects were removed from the sample, only 51 (11 percent) of the non-Hispanic subjects remained, having none of the above indications for TSH testing. Of the 51, 14 had not seen a physician in the preceding 6 months, making it less likely that they would be available for screening even if the benefit were available. We concluded that 8 percent (37 of 469) of the non-Hispanic white Medicare beneficiaries in the sample would be eligible and available for TSH screening. The subjects identified as likely candidates for screening were, on average, 2 years younger than the entire study population and more than twice as likely to be men. Because increasing age and being female are major risk factors for thyroid disease, the screening candidates should be at relatively low risk for thyroid disease.
Among Hispanic subjects, 46 (11 percent) remained, having none of the indications listed for TSH testing. Of the 46, 18 had not seen a physician in the preceding 6 months. We concluded that 7 percent (28 of 414) of the Hispanic Medicare beneficiaries in the sample would be eligible and available for TSH screening. The subjects identified as likely candidates for screening were also, on average, 2 years younger than the entire study population, but not significantly more likely to be men (57 percent versus 51 percent).
Medicare Claims
Analyzing Medicare claims data was the second method the Committee used to estimate the number of Medicare beneficiaries who would become eligible for TSH testing with the establishment of a preventive services benefit. A claim to Medicare for payment is generally required to present documentation that the service provided is medically necessary. This is usually done by submitting a diagnosis (and associated ICD-9-CM code) with the claim. When there is a coverage policy for the service, the diagnosis must be one accepted by the policy in order for the service to be covered and payment to be made.
We attempted to define the screening population by asking, “How many Medicare patients who have never submitted a claim containing a diagnosis with an indication for TSH testing see a physician in a given year?” Answering this question involved some cautions and complications in analysis. The answer could exaggerate the number of potential screening candidates because not all patient diagnoses are entered on claims. A further complication came from the need to limit the time period in which to search for relevant claims. Too short a period of looking back from the reference year would make it more likely that diagnoses will be missed. Too long an observation period will exclude too many beneficiaries who entered the program during the period for which claims are examined. There was also a question of how to approach a patient who had an indication for testing in the past that was transient. For example, a patient who reported constipation 2 years earlier may no longer have this problem in the reference year; testing in the reference year, assuming there were no other indications, would be
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considered screening. However, if the patient received TSH testing as part of the evaluation of his constipation, the patient would not be a candidate for screening if the interval approved for screening was greater than the time since the last TSH test.
To perform this analysis, we created a cohort consisting of 5 percent of Medicare beneficiaries enrolled on January 1, 1997. Using physician and outpatient claims files for 1997, we then examined their submitted claims for diagnoses that are approved for TSH testing under current policy. We divided the diagnoses listed in Appendix C into three groups: (1) diagnoses of thyroid disease, (2) diagnoses of chronic or permanent conditions that would be persistent indications for testing, and (3) diagnoses of possibly transient conditions that would be short-term indications for testing. A patient was considered a candidate for screening in 1997 if he did not submit a claim containing one of the indications for testing and saw a physician whose specialty was general practice, family practice, or internal medicine (including subspecialties) that year; we considered these specialties to be the most likely to do testing for thyroid disease. This would be the potential population size for screening on an annual basis. To look at longer periods, we removed from the cohort all of the subjects in the first and second categories along with those in the third category who actually received a TSH test. We then looked at the claims data for the remaining subjects for 1998, applying the same criteria for potential screening candidates (this time with a 2-year testing interval) and removal from the cohort. This process was repeated for a total of 5 years.
Results from the claims data study are given in Table 5-2. Even when evaluated on the most liberal criteria—no indications for testing listed on claims for 1997 only—just 7.7 percent of beneficiaries would have been available for screening in that year. As was found in the New Mexico study, the potential screening population is younger and more heavily male, hence at lower risk for thyroid dysfunction. As the criteria for screening become stricter by looking for testing indications over a longer period and allowing more subjects to develop indications for testing over a longer screening interval, the potential screening population becomes even smaller, younger, and more likely to be male. With a 5-year
TABLE 5-2 Potential Candidates for Screening Identified by Claims Data
Reference Year
Interval (Years)
% of Medicare Beneficiaries
Average Age in 1997
% Male
1997
1
7.7%
68.3
48.4%
1998
2
4.3%
66.3
51.4%
1999
3
2.7%
65.0
53.3%
2000
4
1.8%
64.1
54.5%
2001
5
1.3%
63.5
55.3%
Total population
71.3
42.5%
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testing interval, looking in 2001 for all claims from 1997 to 2001, candidates for screening make up only 1.3 percent of the Medicare population; they are 55.3 percent male (compared to 42.5 percent male in the total Medicare population) and are, on average, 7.8 years younger than the average Medicare beneficiary. Fewer than 10 percent of these candidates for screening received testing for diabetes or cholesterol; if the remainder of this group were screened for these other conditions instead of being screened for thyroid disease, those who tested positive would have an indication for testing and no longer be considered candidates for screening. For the purposes of our estimates, we have taken the middle figure from Table 5-2, 2.7 percent, as the proportion of Medicare beneficiaries who will be available and newly eligible for serum TSH testing because of the implementation of a screening benefit.
To estimate the proportion of candidates of screening who would be tested, we looked at the population of beneficiaries enrolled in the Medicare program on January 1, 2001. From this group we identified those beneficiaries who (1) did not submit a claim in 2001 with a thyroid disease diagnosis, (2) had a physician visit with one of the specialties most likely to test for thyroid disease, and (3) submitted a claim in 2001 with a diagnosis recognized by current Medicare coverage policy as an indication for serum TSH testing. Of this group, 21 percent received serum TSH testing.
Combining these figures, we estimate that 0.6 percent (21 percent of 2.7 percent) of Medicare beneficiaries, 250,000 at the current population, would be screened if coverage were implemented. This is an imprecise estimate that is dependent on many factors. A short interval between screenings (1 to 2 years) would likely increase the number screened because fewer subjects would develop indications for diagnostic testing; a longer interval would have the opposite effect.
The estimate does not consider the effect of efforts to encourage serum TSH testing that may occur in conjunction with coverage for screening. Such efforts could also lead to “screening” among patients who already have indications for testing. We did not include any increases in testing among this group as being due to coverage for screening because such an effect is not specific to the change in coverage; it could occur in the absence of a change in coverage and as a result of any phenomenon that would encourage testing, such as higher payments or promotion of testing by advocacy groups.
In the absence of efforts to encourage testing, the figure of 21 percent of screening-eligible beneficiaries who see physicians being tested may be too high. This figure did not include patients who may have had indications for TSH testing that were not listed on claims and physicians may have a lower inclination to screen than they do to test patients with indications for diagnostic testing. Using a range of possibilities, 1.3 percent to 7.7 percent available for testing and testing 10 percent to 80 percent of those available, the percentage of Medicare beneficiaries tested could be as low as 0.1 percent or as many as 6.2 percent.
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ESTIMATED COSTS OF SCREENING
Calculating the net costs of a serum TSH screening program entails comparing the incremental medical costs likely to be incurred from screening a population for thyroid dysfunction versus the diagnosis and treatment of thyroid dysfunction that now occurs in usual care. Under usual care, people receive treatment for thyroid dysfunction if their clinicians diagnose it, but there is no systematic screening program. The net costs of a screening program consist of the following components:
Costs of the screening program, including (a) serum TSH tests and (b) evaluation of any positive test results to distinguish people who do not have thyroid dysfunction (false positives) from those who do (true positives);
Net costs of treating thyroid dysfunction, calculated as the difference between (a) the cost of treating thyroid dysfunction detected by the screening program and (b) the cost of treating thyroid dysfunction diagnosed under usual care; and
Any net savings in treatment costs from preventing mortality and morbidity associated with thyroid dysfunction and secondary disorders in (a) people detected by the screening program compared with (b) people under usual care.
Tables 5-3A through 5-3C list the specific medical services that may be involved in screening and treating thyroid dysfunction. Under the screening program (Part A), all people screened would initially receive a serum TSH test, and those with positive test results would receive an office visit, a repeat serum TSH test, and a serum free T4 test to confirm the abnormal results and rule out false positives. Those with high serum TSH results indicating subclinical or overt hypothyroidism (Part B) and those with low serum TSH results indicating subclinical or overt hyperthyroidism (Part C) would subsequently receive additional tests, consultations, visits, and therapies to evaluate and then treat the condition. If treatment for the thyroid dysfunction was effective, it might ameliorate the condition, reduce services associated with unrecognized symptoms of the condition, or reduce services associated with secondary disorders and thereby achieve savings in costs.
TABLE 5-3A Components of a Cost Analysis of Screening for TSH: Screening Program
Detection of dysfunction
Evaluation of positive screening test results
Serum TSH test
Office visit
Serum TSH test
Serum free T4 test
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TABLE 5-3B Components of a Cost Analysis of Screening for TSH: Evaluation and Treatment of Subclinical and Overt Hypothyroidism
Potential Costs
Potential Savings
Evaluation for treatment of hypothyroidism detected by screening
Treatment of hypothyroidism detected by screening
Amelioration of hypothyroidism detected by screening
Serum antithyroid antibody tests
Endocrine consultation
Serum lipid tests
Office visits for follow-up
Serum TSH tests
Thyroid hormone for therapy
Monitoring or treatment for effects of excess thyroid hormone therapy
Reduction in consultations and tests for unrecognized symptoms of hypothyroidism (e.g., depression,constipation, dry skin)
Reduction in treatment, morbidity,or mortality due to secondary disorders or to progression to more severe hypothyroidism (e.g., hyperlipidemia, cardiovascular disease, depression)
TABLE 5-3C Components of a Cost Analysis of Screening for TSH: Evaluation and Treatment of Subclinical and Overt Hyperthyroidism
Potential Costs
Potential Savings
Evaluation for treatment of hyperthyroidism detected by screening
Treatment for hyperthyroidism detected by screening
Amelioration of hyperthyroidism detected by screening
Serum triiodothyronine tests
Serum antithyroid antibody tests
Radioiodine tests
Endocrine consultations
Office visits for follow-up
Serum free T 4 tests
Serum TSH tests
Antithyroid drug or radioactive iodine treatment
Blood counts, liver function tests
Thyroid hormone therapy for hypothyroidism caused by radioactive iodine treatment
Reduction in consultations and tests for unrecognized symptoms of hyperthyroidism (e.g. anxiety,weight loss, cardiac arrhythmia)
Reduction in treatment, morbidity,or mortality due to secondary disorders or to progression to more severe hyperthyroidism (e.g.atrial fibrillation,heart failure, osteoporosis and fracture)
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and the lowest and highest cases contain the range of values that would be associated with the lowest and highest estimates of costs, respectively:
All people with an abnormal screening serum TSH value would have at least an office visit, a repeat serum TSH test, and a serum free T4 test. This is the ideal response to abnormality detected by screening, and the actual proportion having this further evaluation is likely to be lower.
There are no recent data (<10 years old) indicating how physicians would evaluate people with overt thyroid disease and no data at all indicating how they would evaluate people with subclinical thyroid disease; nor are there data indicating what proportion of people with either subclinical hypothyroidism or subclinical hyperthyroidism would be treated. The estimates given are based on the best estimates of the Committee.
In regard to treatment of subclinical hypothyroidism and subclinical hyperthyroidism, it is important to note that most people with either condition have serum TSH concentrations that are close to the limits of normal. This is one reason why the value for the base case is relatively low. The lowest and highest cases are set far apart because of the uncertainty about the proportions likely to be treated. Nearly all people with overt thyroid disease would be treated.
We assumed that all patients who were treated for either subclinical or overt hypothyroidism would have the specified numbers of follow-up visits and tests. Therefore, the numbers of people listed at the bottom of Table 5-4A, are the combined numbers for the subclinical and overt groups.
The causes of both subclinical and overt hyperthyroidism were assumed to be Graves’ disease (50 percent), nodular goiter (30 percent), and thyroiditis and other causes (20 percent). (There are no published data concerning the causes of subclinical hyperthyroidism as detected by screening.) We assumed that considerably fewer patients with subclinical hyperthyroidism would be treated (base case, 30 percent versus 90 percent for overt hyperthyroidism) because many of the former have only very slightly high serum TSH concentrations (and some would have thyroiditis and need no treatment). We assumed that 50 percent of people with subclinical hyperthyroidism and 50 percent of those with overt hyperthyroidism who were treated would be given radioactive iodine, and the other 50 percent would receive an anti-thyroid drug.
For both subclinical and overt hyperthyroidism, we assumed that all people who were treated would receive three office visits and sets of tests in the first year of treatment and that the number of visits and tests would be independent of the type of treatment.
Some people (estimated as 50 percent because people with both Graves’ disease and nodular goiter are included) treated for hyperthyroidism with radioactive iodine would develop hypothyroidism. (We assumed this would occur during year 1.) Therefore, in year 2 and thereafter, they would be followed according to the schedule for people with hypothyroidism in Table 5-4A. We
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recognize that this treatment is more likely to cause hypothyroidism in people with Graves’ disease than in those with nodular goiter and consider the estimate of 50 percent to be very crude. Moreover, a few people treated with radioactive iodine would probably develop hypothyroidism later.
For years 2 and thereafter, the remaining people with hyperthyroidism who were treated would be followed as indicated at the bottom of Table 5-4B. Some of these people might be treated with radioactive iodine and others, particularly those with Graves’ disease, might have a remission of their disease and need no antithyroid drug treatment and less frequent testing.
There are no published data that address the question of optimal follow-up for people with either hypothyroidism or hyperthyroidism.
Many more branches or steps could be added to this table. For example, the types of diagnostic studies were limited. As we have noted, we assumed that all people who were treated for hypothyroidism or hyperthyroidism would have the specified follow-up visits and tests, an unlikely outcome in clinical practice. The combining of visits and tests during and after treatment for hyperthyroidism independent of the particular treatment given is certainly an oversimplification. We have made no provision for the side effects of antithyroid drug or radioactive iodine therapy, except for radioactive iodine-induced hypothyroidism.
The unit costs for each visit, test, and treatment are shown in Tables 5-5A and 5-5B. Price information for all services except prescription drugs were obtained from the Medicare program’s published Fee Schedules for 2003 (Centers for Medicare and Medicaid Services, 2003). Where fee schedule amounts differed among localities, the median figure was used. Prescription drug prices were obtained from an Internet prescription drug price search engine (DestinationRx, Inc., 2003) that compares prices from major national retail sources, including shipping costs. The prices selected for methimazole and propylthiouracil represent the mid-point between the highest and lowest prices quoted for 100 pills. The price chosen for levothyroxine was the lowest quoted price for 100 tablets of the leading brand name.
Tables 5-6A through 5-6C show our cost estimates for each 1 million Medicare beneficiaries screened. A large proportion of the cost comes from lifetime monitoring and drug treatment. Because the portion of the Medicare population affected by screening would be younger and healthier than average, we estimated the average life expectancy of beneficiaries who screen positively and are treated to be 17 years, the average life expectancy for individuals ages 66 and 67 (National Center for Health Statistics, 2002). As Table 5-6A shows, our base case cost estimate for the screening test itself is $23.5 million, all of which would be paid by the Medicare program. The lifetime cost estimate of treatment and follow-up for those patients whose initial test results indicated hypothyroidism (Table 5-6B) was $98.8 million per million subjects screened; $46.6 million would be paid by Medicare and $52.2 million would paid by Medicare beneficia
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TABLE 5-5A Prices of Services Required for Follow-up and Treatment After Abnormal Results of Thyroid Screening: Subclinical and Overt Hypothyroidism
CPT© Codea
Costb
Screening serum TSH value high
Follow-up
Office visitc
99213
$47.18
Repeat serum TSH test
84443
$23.47
Serum free T4 test
84439
$12.60
Serum antithyroid antibody testd
86376
$20.33
Outcome 1: Normal
Repeat serum TSH value normal
Years 2-5:
Follow-up serum TSH tests
84443
$23.47
Outcome 2: Subclinical hypothyroidism
Year 1
Endocrine consultation
99241
$43.83
Levothyroxine treatment, 0.1 mg/day
$0.315/day
Outcome 3: Overt hypothyroidism
Year 1
Endocrine consultation
99242
$81.70
Levothyroxine treatment, 0.1 mg/day
$0.315/day
Follow-up after treatment (either subclinical or overt hypothyroidism)
Year 1, after treatment started
Follow-up office visits,c 2
99212
$33.57
Follow-up serum TSH tests, 2
84443
$23.47
Years 2 and beyond
Lifelong levothyroxine treatment
$0.315/day
Follow-up office visits,c 2/year
99212
$33.57
Follow-up serum TSH tests, 2/year
84443
$23.47
aCommon Procedural Terminology codes, copyright 2003, American Medical Association.
bAll prices except for prescription drugs (levothyroxine, methimazole, and propylthiouracil) are from 2003 Medicare Fee Schedules (Centers for Medicare & Medicaid Services, 2003). Prescription drug prices were obtained from the DestinationRx website (DestinationRx, 2003).
cInitial office visits after a screening test is found to be positive in all groups is estimated as requiring more than minimum time
dMeasurement of serum antithyroid peroxidase (microsomal) antibody.
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TABLE 5-5B Prices of Services Required for Follow-up and Treatment After Abnormal Results of Thyroid Screening: Subclinical and Overt Hyperthyroidism
CPT© Codea
Costb
Screening serum TSH value low
Follow-up
Office visitc
99213
$47.18
Repeat serum TSH test
84443
$23.47
Serum free T4 test
84439
$12.60
Outcome 1: Normal (repeat serum TSH value normal)
Years 2-5:
Follow-up serum TSH tests
84443
$23.47
Outcomes 2:and 3: Hyperthyroidism
Year 1
Serum triiodothyronine test
84480
$19.81
Serum antithyroid antibody testd
86376
$20.33
Radioiodine test
78000
$43.64
Endocrine consultatione
99242
$81.70
Antithyroid treatment
Radioactive iodine
Radiopharmaceutical therapyf
79000
$177.41
Radioactive iodineg
$87.50
Antithyroid drug treatment
Methimazole 10 mg/day
$0.685/day
Propylthiouracil 300 mg/day
$1.20/day
Follow-up after any treatment started (either subclinical or overt hyperthyroidism)
Year 1
Follow-up office visits,c 3
99212
$33.57
Serum free T4 tests, 3
84439
$12.60
Serum TSH tests, 3
84443
$23.47
Hypothyroidism after radioactive iodine treatment (all treated with T4)
Years 2 and beyond
Follow-up of group with hypothyroidism after radioactive iodine treatment in year 1
Lifelong levothyroxine treatment
$0.315/day
Follow-up office visits,c 2/year
99212
$33.57
Follow-up serum TSH tests, 2/year
84443
$23.47
Follow-up of all other groups
(euthyroid after radioactive iodine and antithyroid drug treatment)
Follow-up office visits,c 3/year
99212
$33.57
Follow-up serum TSH tests, 3/year
84443
$23.47
Follow-up serum free T4 tests, 3/year
84439
$12.60
aCommon Procedural Terminology codes, copyright 2003, American Medical Association.
bAll prices except for prescription drugs (levothyroxine, methimazole, and propylthiouracil) are from 2003 Medicare Fee Schedules (Centers for Medicare & Medicaid Services, 2003). Prescription drug prices were obtained from the DestinationRx Web site (DestinationRx, 2003).
cInitial office visits after a screening test is found to be positive in all groups is estimated as requiring more than minimum time, whereas later visits are minimum-time visits.
dMeasurement of serum antithyroid peroxidase (microsomal) antibody.
eOffice endocrine consultation visits are categorized as requiring 30 minutes for both subclinical and overt thyroid dysfunction.
fOffice consultation with nuclear medicine physician for radioiodine treatment.
gI-131 capsules, 15mCi dose
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TABLE 5-6A Cost Estimates for Thyroid Screening, per 1 Million Medicare Beneficiaries—Initial Screening
Base Cost
Screening
Total
Medicare Other
Payer
Serum TSH Tests
$23,470,000
$23,470,000
TABLE 5-6B Cost Estimates for Thyroid Screening, per 1 Million Medicare Beneficiaries—Subclinical and Overt Hypothyroidism
Base Cost
Total
Medicare
Other Payer
Follow-up - screening TSH value high
Office visit
$2,830,800
$2,264,640
$566,160
Repeat serum TSH test
$1,408,200
$1,408,200
Serum free T4 test
$756,000
$756,000
Serum antithyroid antibody test
$609,900
$609,900
Outcome 1: Repeat test normal
Years 2-5 Follow-up TSH tests
$218,101
$218,101
Outcome 2: Subclinical hypothyroidism
Year 1
Endocrine consultation
$591,705
$473,364
$118,341
T4 treatment
$3,071,935
$3,071,935
Outcome 3: Overt hypothyroidism
Year 1
Endocrine consultation
$116,423
$93,138
$23,285
T4 treatment
$324,260
$324,260
Follow-up after treatment (subclinical or overt hypothyroidism)
Year 1, after treatment started
Follow-up office visits, 2
$2,004,129
$1,603,303
$400,826
Follow-up serum TSH tests, 2
$1,401,159
$1,401,159
Subsequent years
Lifelong Levothyroxine
$42,659,951
$42,659,951
Follow-up office visits, 2/year
$25,174,069
$20,139,255
$5,034,814
Follow-up serum TSH tests, 2/year
$17,600,101
$17,600,101
Total Cost – Hypothyroidism
$98,766,732
$46,567,161
$52,199,571
NOTE: Costs after the first year are discounted at 3% per year in the base and lowest cost estimates. No discounting is used in the highest cost estimate
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Highest Cost
Lowest Cost
Total
Medicare
Other Payer
Total
Medicare
Other Payer
$23,470,000
$23,470,000
$23,470,000
$23,470,000
Highest Cost
Lowest Cost
Total
Medicare
Other Payer
Total
Medicare
Other Payer
$2,830,800
$2,264,640
$566,160
$2,830,800
$2,264,640
$566,160
$1,408,200
$1,408,200
$1,408,200
$1,408,200
$756,000
$756,000
$756,000
$756,000
$1,016,500
$1,016,500
$203,300
$203,300
$328,580
$328,580
$87,240
$87,240
$1,065,069
$852,055
$213,014
$236,682
$189,346
$47,336
$5,529,483
$5,529,483
$1,228,774
$1,228,774
$122,550
$98,040
$24,510
$98,040
$78,432
$19,608
$341,326
$341,326
$273,061
$273,061
$3,464,424
$2,771,539
$692,885
$886,248
$708,998
$177,250
$1,401,159
$1,401,159
$1,401,159
$1,401,159
$93,932,950
$93,932,950
$18,864,702
$18,864,702
$55,430,784
$44,344,627
$11,086,157
$11,132,252
$8,905,801
$2,226,450
$38,753,664
$38,753,664
$7,782,959
$7,782,959
$206,381,489
$93,995,005
$112,386,484
$47,189,417
$23,786,076
$23,403,341
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TABLE 5-6C Cost Estimates for Thyroid Screening, per 1 Million Medicare Beneficiaries—Subclinical and Overt Hyperthyroidism
Base Cost
Total
Medicare
Other Payer
Follow-up - screening serum TSH value low
Office visit
$471,800
$377,440
$94,360
Repeat serum TSH test
$234,700
$234,700
Serum free T4 test
$126,000
$126,000
Outcome 1: Normal - Repeat serum TSH value normal
Years 2-5 Follow-up TSH tests
$69,792
$69,792
Outcome 2: Subclinical hyperthyroidism
Serum triiodothyronine test
$84,193
$84,193
Serum antithyroid antibody test
$51,842
$51,842
Radioiodine tests
$111,282
$89,026
$22,256
Endocrine consultation
$347,225
$277,780
$69,445
Antithyroid treatment
Radioactive iodine
$337,760
$278,687
$59,073
Antithyroid drug treatment
$390,950
$390,950
Outcome 3: Overt hyperthyroidism
Serum triiodothyronine test
$2,972
$2,972
Serum antithyroid antibody
$5,083
$5,083
Radioiodine tests
$10,910
$8,728
$2,182
Endocrine consultation
$32,680
$26,144
$6,536
Antithyroid treatment
Radioactive iodine
$59,605
$49,180
$10,425
Antithyroid drug treatment
$68,991
$68,991
Year 1 Follow-up after treatment started (all treated people)
Follow-up office visits, 3
$302,130
$241,704
$60,426
Serum free T4 tests, 3
$113,400
$113,400
Serum TSH tests, 3
$211,230
$211,230
Follow-up hypothyroidism after radioactive iodine treatment
Lifelong T4 treatment
$1,071,858
$1,071,858
Follow-up office visits, 2/year
$632,514
$506,011
$126,503
Follow-up TSH tests, 2/year
$442,214
$442,214
Follow-up of euthyroid after either radioactive iodine or antithyroid drug treatment
Follow-up office visits, 3/year
$2,846,314
$2,277,051
$569,263
Follow-up TSH tests, 3/year
$1,989,961
$1,989,961
Follow-up free T4 tests, 3/year
$1,068,322
$1,068,322
Total Cost – Hyperthyroidism
$11,083,726
$8,531,458
$2,552,268
NOTE: Costs after the first year are discounted at 3% per year in the base and lowest cost estimates. No discounting is used in the highest cost estimate
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Highest Cost
Lowest Cost
Total
Medicare
Other Payer
Total
Medicare
Other Payer
$471,800
$377,440
$94,360
$471,800
$377,440
$94,360
$234,700
$234,700
$234,700
$234,700
$126,000
$126,000
$126,000
$126,000
$105,615
$105,615
$17,448
$17,448
$134,708
$134,708
$33,677
$33,677
$103,683
$103,683
$8,640
$8,640
$222,564
$178,051
$44,513
$37,094
$29,675
$7,419
$555,560
$444,448
$111,112
$138,890
$111,112
$27,778
$788,107
$650,270
$137,838
$112,587
$92,896
$19,691
$912,216
$912,216
$130,317
$130,317
$5,943
$5,943
$495
$495
$8,132
$8,132
$1,017
$1,017
$17,456
$13,965
$3,491
$4,364
$3,491
$873
$40,850
$32,680
$8,170
$24,510
$19,608
$4,902
$66,228
$54,645
$11,583
$46,359
$38,251
$8,108
$76,657
$76,657
$53,660
$53,660
$649,580
$519,664
$129,916
$120,852
$96,682
$24,170
$243,810
$243,810
$45,360
$45,360
$454,145
$454,145
$84,492
$84,492
$2,934,494
$2,934,494
$428,743
$428,743
$1,731,675
$1,385,340
$346,335
$253,006
$202,405
$50,601
$1,210,676
$1,210,676
$176,885
$176,885
$7,795,760
$6,236,608
$1,559,152
$1,138,526
$910,821
$227,705
$5,450,297
$5,450,297
$795,984
$795,984
$2,926,022
$2,926,022
$427,329
$427,329
$27,266,678
$20,896,841
$6,369,837
$4,912,735
$3,834,408
$1,078,327
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ries or supplementary insurance. Most of the cost not paid by Medicare, $42.7 million, is for prescription drugs. The lifetime cost estimate of treatment and follow-up for those patients whose initial test results indicated hyperthyroidism (Table 5-6C) was $11.1 million per million subjects screened; $8.5 million would be paid by Medicare and $2.6 million would paid by Medicare beneficiaries or supplementary insurance. Again, most of the cost not paid by Medicare, $1.5 million, is for prescription drugs. These estimates are very sensitive to the proportion of subjects tested who have positive screening results: An increase of 1 percent in the prevalence of elevated serum TSH levels (from 6 percent to 7 percent) would raise the base cost estimate for hypothyroidism by $16.5 million per million subjects screened. An increase in the prevalence of low serum TSH levels from 1 percent to 2 percent would increase the base cost estimate for hyperthyroidism by $11.1 million.
Combining our estimates of the number of beneficiaries screened with the estimates of costs per million beneficiaries screened, we can estimate the annual cost to the Medicare program. These results are given in Tables 5-7A through 5-7C. Our base estimates of 250,000 beneficiaries screened would cost Medicare $5.9 million for the screening tests, $11.6 million for follow-up and treatment of suspected hypothyroidism and $2.1 million for follow-up and treatment for suspected hyperthyroidism.
CONCLUSIONS
Estimates of the costs of screening require an estimate of the number of subjects who will be screened and the net costs incurred (or saved) as a result of screening.
Historically, the use of preventive services by Medicare beneficiaries has been considerably less than universal among those covered for the service; important factors have limited demand or created other barriers to use. In the case of serum TSH testing, more than 90 percent of Medicare beneficiaries have indications for testing that are already covered by the Medicare program. Aside from beneficiaries with known thyroid disease, fewer than 25 percent of beneficiaries with these indications are tested annually. On this basis, the Committee estimates that a relatively small number of Medicare beneficiaries would take advantage of a serum TSH screening benefit; our best estimate is 250,000 annually.
The Committee found a widespread lack of information necessary to make a meaningful assessment of the true economic costs of screening. It could not estimate costs avoided or other possible benefits resulting from screening or whether any costs incurred would be postponed rather than avoided if screening were not done. The Committee was able to estimate the health care resources likely to be expended as a consequence of screening. Our best estimate for 250,000 beneficiaries screened was $33.3 million annually. The Medicare program would pay $19.6 million of this total; supplementary insurance or the beneficiaries themselves would pay the remainder.
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TABLE 5-7A Cost Estimates Based on Size of Screening Population: Initial Screening Tests – Cost to Medicare
Number Screened
Base
Lowest
Highest
250,000
$5,867,500
$5,867,500
$5,867,500
40,000
$938,800
$938,800
$938,800
2,500,000
$58,675,000
$58,675,000
$58,675,000
NOTE: No payment by other sources
TABLE 5-7B Cost Estimates Based on Size of Screening Population: Follow-up and Treatment for Suspected Hypothyroidism
Number Screened
Base
Lowest
Highest
Medicare
250,000
$11,641,790
$5,946,519
$23,498,751
40,000
$1,862,686
$951,443
$3,759,800
2,500,000
$116,417,903
$59,465,190
$234,987,512
Other Payers
250,000
$13,049,893
$5,850,835
$28,096,621
40,000
$2,087,983
$936,134
$4,495,459
2,500,000
$130,498,928
$58,508,353
$280,966,211
Total Cost
250,000
$24,691,683
$11,797,354
$51,595,372
40,000
$3,950,669
$1,887,577
$8,255,260
2,500,000
$246,916,831
$117,973,543
$515,953,722
TABLE 5-7C Cost Estimates Based on Size of Screening Population: Follow-up and Treatment for Suspected Hyperthyroidism
Number Screened
Base
Lowest
Highest
Medicare
250,000
$2,132,865
$958,602
$5,224,210
40,000
$341,258
$153,376
$835,874
2,500,000
$21,328,646
$9,586,019
$52,242,102
Other Payers
250,000
$638,067
$269,582
$1,592,459
40,000
$102,091
$43,133
$254,793
2,500,000
$6,380,671
$2,695,818
$15,924,593
Total Cost
250,000
$2,770,932
$1,228,184
$6,816,670
40,000
$443,349
$196,509
$1,090,667
2,500,000
$27,709,316
$12,281,837
$68,166,696
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REFERENCES
Arbelle JE, Porath A. 1999. Practice guidelines for the detection and management of thyroid dysfunction. A comparative review of the recommendations. Clin Endocrinol 51(1):11–18.
Canaris GJ, Manowitz NR, Mayor G, Ridgway EC. 2000. The Colorado thyroid disease prevalence study. Arch Intern Med 160(4):526–534.
Centers for Disease Control and Prevention. 2001. Behavioral Risk Factor Surveillance System. [Online]. Available: http://www.cdc.gov/brfss/index.htm [accessed December 26, 2002].
Centers for Medicare & Medicaid Services. 2001. Medicare national coverage decision for thyroid testing. Federal Register 66(226):58853–58857.
Centers for Medicare & Medicaid Services. 2003. Medicare Payment Systems. [Online]. Available: http://www.cms.gov/paymentsystems/ [accessed January 14, 2003].
DestinationRx, Inc. DestinationRx.com. [Online]. Available: http://destinationrx.com/ default_nonmember.asp [accessed January 12, 2003].
Elder JP, Ayala GX, Harris S. 1999. Theories and intervention approaches to health-behavior change in primary care. Am J Prev Med 17(4):275–284.
Hollowell JG, Staehling NW, Flanders WD, Hannon WH, Gunter EW, Spencer CA, Braverman LE. 2002. Serum TSH, T(4), and thyroid antibodies in the United States population (1988 to 1994): National Health and Nutrition Examination Survey (NHANES III). J Clin Endocrinol Metab 87(2):489–499.
IOM (Institute of Medicine). 1990. Clinical Practice Guidelines: Directions for a New Program. Washington, DC: National Academy Press.
IOM. 2002. Guidance for the National Healthcare Disparities Report. Washington, DC: National Academies Press.
Lindeman RD, Schade DS, LaRue A, Romero LJ, Liang HC, Baumgartner RN, Koehler KM, Garry PJ. 1999. Subclinical hypothyroidism in a biethnic, urban community. J Am Geriatr Soc 47(6):703–709.
McBean AM. (October 31, 2002) What can we learn from prior experience of Medicare reimbursement for screening and clinical preventive services. Presentation at Institute of Medicine Workshop on Screening for Thyroid Dysfunction.
National Center for Health Statistics. 2002. Life expectancy at single years of age, United States, 1999. National Vital Statistics Report 50(6):7–8.
Parle JV, Franklyn JA, Cross KW, Jones SC, Sheppard MC. 1991. Prevalence and follow-up of abnormal thyrotrophin (TSH) concentrations in the elderly in the United Kingdom. Clin Endocrinol 34(1):77–83.
U.S. Department of Health and Human Services. 1998. 1998 HCFA Statistics.
GAO (U.S. General Accounting Office). 2002. Medicare Beneficiary Use of Clinical Preventive Services. GAO-02-422. [Online]. Available: http// www.gao.gov/new.items/d02422.pdf .
United States Preventive Services Task Force. 1996. Screening for thyroid disease. Guide to Clinical Preventive Services, 2nd edition [Online]. Available: http://hstat.nlm.nih.gov/hq/Hquest/fws/T/ db/local.gcps.cps/screen/Browse/s/50802/action/GetText/linek/285.
Vanderpump MP, Tunbridge WM, French JM, Appleton D, Bates D, Clark F, Grimley Evans J, Hasan DM, Rodgers H, Tunbridge F, et al. 1995. The incidence of thyroid disorders in the community: A twenty-year follow-up of the Whickham survey. Clin Endocrinol 43(1):55–68.