Cynthia D. Smith, MD, FACP

In Reply: Thanks so much for sharing your thoughts on our article. We share your frustration with the lack of evidence to support the decision to avoid stress testing in all asymptomatic individuals. In fact, there is no direct evidence that the identification and treatment of screening-detected, asymptomatic coronary artery disease will decrease mortality risk and improve outcomes in patients with no history of coronary artery disease.

The focus of our article was to review the available evidence and guidelines on stress testing low-risk, asymptomatic patients. The statement in the article that you cite, “a physician may consider ordering exercise electrocardiography in asymptomatic adults with intermediate risk of coronary heart disease,” was pulled from the 2010 American College of Cardiology/American Heart Association guideline¹ in an attempt to summarize recent guidelines on this issue. Unfortunately, there is currently insufficient evidence to recommend for or against screening in patients at intermediate risk for coronary heart disease. As a result, the decision to perform stress testing in an asymptomatic patient at intermediate risk should include an informed discussion between the physician and patient. In contrast, there is considerable evidence supporting the recommendation not to screen in asymptomatic low-risk individuals, which is the main conclusion of our article.

In Reply: Thanks so much for sharing your thoughts on our article. We share your frustration with the lack of evidence to support the decision to avoid stress testing in all asymptomatic individuals. In fact, there is no direct evidence that the identification and treatment of screening-detected, asymptomatic coronary artery disease will decrease mortality risk and improve outcomes in patients with no history of coronary artery disease.

The focus of our article was to review the available evidence and guidelines on stress testing low-risk, asymptomatic patients. The statement in the article that you cite, “a physician may consider ordering exercise electrocardiography in asymptomatic adults with intermediate risk of coronary heart disease,” was pulled from the 2010 American College of Cardiology/American Heart Association guideline¹ in an attempt to summarize recent guidelines on this issue. Unfortunately, there is currently insufficient evidence to recommend for or against screening in patients at intermediate risk for coronary heart disease. As a result, the decision to perform stress testing in an asymptomatic patient at intermediate risk should include an informed discussion between the physician and patient. In contrast, there is considerable evidence supporting the recommendation not to screen in asymptomatic low-risk individuals, which is the main conclusion of our article.

In Reply: Thanks so much for sharing your thoughts on our article. We share your frustration with the lack of evidence to support the decision to avoid stress testing in all asymptomatic individuals. In fact, there is no direct evidence that the identification and treatment of screening-detected, asymptomatic coronary artery disease will decrease mortality risk and improve outcomes in patients with no history of coronary artery disease.

The focus of our article was to review the available evidence and guidelines on stress testing low-risk, asymptomatic patients. The statement in the article that you cite, “a physician may consider ordering exercise electrocardiography in asymptomatic adults with intermediate risk of coronary heart disease,” was pulled from the 2010 American College of Cardiology/American Heart Association guideline¹ in an attempt to summarize recent guidelines on this issue. Unfortunately, there is currently insufficient evidence to recommend for or against screening in patients at intermediate risk for coronary heart disease. As a result, the decision to perform stress testing in an asymptomatic patient at intermediate risk should include an informed discussion between the physician and patient. In contrast, there is considerable evidence supporting the recommendation not to screen in asymptomatic low-risk individuals, which is the main conclusion of our article.

A 38-year-old man is evaluated in an urgent care center for back pain. He is a high school mathematics teacher who reports the insidious onset of low back pain 3 weeks ago. Over the last week the pain has become constant, is worsened by movement, and does not respond to naproxen. He has no history of trauma, malignancy, fever, weight loss, or bladder or bowel symptoms. He does not use intravenous drugs. On examination, he appears uncomfortable and stiff, protecting his back against motion. He has intact sensation, strength, and reflexes. The straight-leg-raising maneuver reproduces his lower back pain but does not cause radicular pain. Should I now order an imaging study such as spinal radiography, computed tomography, or magnetic resonance imaging to direct therapy?

IMAGING STUDIES ARE UNLIKELY TO HELP

This man with acute, nonspecific low back pain does not need spinal imaging. Imaging—ie, spine radiography, computed tomography, or magnetic resonance imaging—is unlikely to be helpful in a patient with nonspecific low back pain and may expose him unnecessarily to radiation and the anxiety of findings that are clinically insignificant.

Imaging studies are often ordered inappropriately as part of the evaluation of back pain in patients such as this. In 2008, the total national cost of treating spine (neck and back) problems was estimated to be $86 billion, representing 9% of total health care costs, which is close to the estimated $89 billion per year spent on cancer care.¹

Spine imaging should be considered only in patients who have a “red flag” such as advanced age, history of trauma, history of cancer, and prolonged corticosteroid use, all of which have been associated with an increased probability (from 9% to 33%) of either spinal fracture or malignancy.² Other red flags include duration longer than 6 weeks, fever, weight loss, and progressive neurologic findings on examination. This patient has none of these.

GUIDELINES AND CHOOSING WISELY

High-quality guidelines from different groups recommend against spine imaging in patients with low back pain.^3–6 These guidelines vary slightly in their patient populations and definitions of uncomplicated low back pain.

The American College of Radiology⁴ and the American College of Occupational and Environmental Medicine⁶ recommend against imaging for patients with both nonspecific and radicular low back pain in the first 6 weeks as long as no red flags are present.

The National Institute for Health and Clinical Excellence³ and, jointly, the American College of Physicians and American Pain Society (ACP/APS)⁵ recommend against imaging for patients with nonspecific low back pain in both the acute and chronic settings. Nonspecific low back pain is defined as pain without signs of a serious underlying condition (eg, cancer, infection, cauda equina syndrome), spinal stenosis or radiculopathy, or another specific spinal cause (eg, vertebral compression fracture, ankylosing spondylitis).

In addition, imaging in patients with nonspecific low back pain is one of the top five practices that should be questioned by physicians and patients, according to the American Board of Internal Medicine Foundation in its Choosing Wisely campaign (www.choosingwisely.org).

HARMS ASSOCIATED WITH SPINE IMAGING

Several guidelines cite radiation exposure as a potential harmful consequence of spinal imaging by plain radiography and computed tomography. The American College of Radiology guideline⁴ estimates that the radiation exposure of plain lumbar radiography or lumbar computed tomography ranges between 1 and 10 mSv (3 mSv is the annual amount of ambient radiation in the United States), placing both studies in the medium-range category for relative radiation exposure. The ACP/APS guideline⁵ states that radiation exposure from imaging is a reason to dissuade clinicians from routine use.

Although lumbar magnetic resonance imaging does not carry the risk of radiation exposure, it may result in harm by detecting clinically insignificant abnormalities in more than 30% of patients.⁷ These incidental findings increase with age and may lead to additional and possibly unnecessary testing and invasive treatments. The American College of Occupational and Environmental Medicine guideline⁶ also cites the high prevalence of abnormal findings on plain radiography, magnetic resonance imaging, and other diagnostic tests that are unrelated to symptoms.

CLINICAL BOTTOM LINE

On the basis of current data, the patient described at the beginning of this article should not undergo spine imaging; the results are unlikely to affect his medical management and improve his clinical outcome, and imaging carries a small risk of harm.

A practical approach would be to treat his pain with simple analgesia (a different nonsteroidal anti-inflammatory drug or acetaminophen), address his functional challenges, and reassure him that his chance of having a serious underlying cause of back pain is low (< 1%). He should be told to expect significant improvement in his symptoms within 30 days, be encouraged to stay active, and should be offered patient-focused self-help resources.

The recommendation to conservatively manage patients at low risk without imaging is consistent among all four guidelines. Imaging can be considered for a small subset of patients at high risk with red-flag indications. Potential harms associated with routine imaging of all patients with low back pain include radiation exposure and the high rate of clinically insignificant abnormalities that may lead to unnecessary and invasive interventions that increase expense, patient risk, and anxiety without improving outcomes.

A 38-year-old man is evaluated in an urgent care center for back pain. He is a high school mathematics teacher who reports the insidious onset of low back pain 3 weeks ago. Over the last week the pain has become constant, is worsened by movement, and does not respond to naproxen. He has no history of trauma, malignancy, fever, weight loss, or bladder or bowel symptoms. He does not use intravenous drugs. On examination, he appears uncomfortable and stiff, protecting his back against motion. He has intact sensation, strength, and reflexes. The straight-leg-raising maneuver reproduces his lower back pain but does not cause radicular pain. Should I now order an imaging study such as spinal radiography, computed tomography, or magnetic resonance imaging to direct therapy?

IMAGING STUDIES ARE UNLIKELY TO HELP

This man with acute, nonspecific low back pain does not need spinal imaging. Imaging—ie, spine radiography, computed tomography, or magnetic resonance imaging—is unlikely to be helpful in a patient with nonspecific low back pain and may expose him unnecessarily to radiation and the anxiety of findings that are clinically insignificant.

Imaging studies are often ordered inappropriately as part of the evaluation of back pain in patients such as this. In 2008, the total national cost of treating spine (neck and back) problems was estimated to be $86 billion, representing 9% of total health care costs, which is close to the estimated $89 billion per year spent on cancer care.¹

Spine imaging should be considered only in patients who have a “red flag” such as advanced age, history of trauma, history of cancer, and prolonged corticosteroid use, all of which have been associated with an increased probability (from 9% to 33%) of either spinal fracture or malignancy.² Other red flags include duration longer than 6 weeks, fever, weight loss, and progressive neurologic findings on examination. This patient has none of these.

GUIDELINES AND CHOOSING WISELY

High-quality guidelines from different groups recommend against spine imaging in patients with low back pain.^3–6 These guidelines vary slightly in their patient populations and definitions of uncomplicated low back pain.

The American College of Radiology⁴ and the American College of Occupational and Environmental Medicine⁶ recommend against imaging for patients with both nonspecific and radicular low back pain in the first 6 weeks as long as no red flags are present.

The National Institute for Health and Clinical Excellence³ and, jointly, the American College of Physicians and American Pain Society (ACP/APS)⁵ recommend against imaging for patients with nonspecific low back pain in both the acute and chronic settings. Nonspecific low back pain is defined as pain without signs of a serious underlying condition (eg, cancer, infection, cauda equina syndrome), spinal stenosis or radiculopathy, or another specific spinal cause (eg, vertebral compression fracture, ankylosing spondylitis).

In addition, imaging in patients with nonspecific low back pain is one of the top five practices that should be questioned by physicians and patients, according to the American Board of Internal Medicine Foundation in its Choosing Wisely campaign (www.choosingwisely.org).

HARMS ASSOCIATED WITH SPINE IMAGING

Several guidelines cite radiation exposure as a potential harmful consequence of spinal imaging by plain radiography and computed tomography. The American College of Radiology guideline⁴ estimates that the radiation exposure of plain lumbar radiography or lumbar computed tomography ranges between 1 and 10 mSv (3 mSv is the annual amount of ambient radiation in the United States), placing both studies in the medium-range category for relative radiation exposure. The ACP/APS guideline⁵ states that radiation exposure from imaging is a reason to dissuade clinicians from routine use.

Although lumbar magnetic resonance imaging does not carry the risk of radiation exposure, it may result in harm by detecting clinically insignificant abnormalities in more than 30% of patients.⁷ These incidental findings increase with age and may lead to additional and possibly unnecessary testing and invasive treatments. The American College of Occupational and Environmental Medicine guideline⁶ also cites the high prevalence of abnormal findings on plain radiography, magnetic resonance imaging, and other diagnostic tests that are unrelated to symptoms.

CLINICAL BOTTOM LINE

On the basis of current data, the patient described at the beginning of this article should not undergo spine imaging; the results are unlikely to affect his medical management and improve his clinical outcome, and imaging carries a small risk of harm.

A practical approach would be to treat his pain with simple analgesia (a different nonsteroidal anti-inflammatory drug or acetaminophen), address his functional challenges, and reassure him that his chance of having a serious underlying cause of back pain is low (< 1%). He should be told to expect significant improvement in his symptoms within 30 days, be encouraged to stay active, and should be offered patient-focused self-help resources.

The recommendation to conservatively manage patients at low risk without imaging is consistent among all four guidelines. Imaging can be considered for a small subset of patients at high risk with red-flag indications. Potential harms associated with routine imaging of all patients with low back pain include radiation exposure and the high rate of clinically insignificant abnormalities that may lead to unnecessary and invasive interventions that increase expense, patient risk, and anxiety without improving outcomes.

A 38-year-old man is evaluated in an urgent care center for back pain. He is a high school mathematics teacher who reports the insidious onset of low back pain 3 weeks ago. Over the last week the pain has become constant, is worsened by movement, and does not respond to naproxen. He has no history of trauma, malignancy, fever, weight loss, or bladder or bowel symptoms. He does not use intravenous drugs. On examination, he appears uncomfortable and stiff, protecting his back against motion. He has intact sensation, strength, and reflexes. The straight-leg-raising maneuver reproduces his lower back pain but does not cause radicular pain. Should I now order an imaging study such as spinal radiography, computed tomography, or magnetic resonance imaging to direct therapy?

IMAGING STUDIES ARE UNLIKELY TO HELP

This man with acute, nonspecific low back pain does not need spinal imaging. Imaging—ie, spine radiography, computed tomography, or magnetic resonance imaging—is unlikely to be helpful in a patient with nonspecific low back pain and may expose him unnecessarily to radiation and the anxiety of findings that are clinically insignificant.

Imaging studies are often ordered inappropriately as part of the evaluation of back pain in patients such as this. In 2008, the total national cost of treating spine (neck and back) problems was estimated to be $86 billion, representing 9% of total health care costs, which is close to the estimated $89 billion per year spent on cancer care.¹

Spine imaging should be considered only in patients who have a “red flag” such as advanced age, history of trauma, history of cancer, and prolonged corticosteroid use, all of which have been associated with an increased probability (from 9% to 33%) of either spinal fracture or malignancy.² Other red flags include duration longer than 6 weeks, fever, weight loss, and progressive neurologic findings on examination. This patient has none of these.

GUIDELINES AND CHOOSING WISELY

High-quality guidelines from different groups recommend against spine imaging in patients with low back pain.^3–6 These guidelines vary slightly in their patient populations and definitions of uncomplicated low back pain.

The American College of Radiology⁴ and the American College of Occupational and Environmental Medicine⁶ recommend against imaging for patients with both nonspecific and radicular low back pain in the first 6 weeks as long as no red flags are present.

The National Institute for Health and Clinical Excellence³ and, jointly, the American College of Physicians and American Pain Society (ACP/APS)⁵ recommend against imaging for patients with nonspecific low back pain in both the acute and chronic settings. Nonspecific low back pain is defined as pain without signs of a serious underlying condition (eg, cancer, infection, cauda equina syndrome), spinal stenosis or radiculopathy, or another specific spinal cause (eg, vertebral compression fracture, ankylosing spondylitis).

In addition, imaging in patients with nonspecific low back pain is one of the top five practices that should be questioned by physicians and patients, according to the American Board of Internal Medicine Foundation in its Choosing Wisely campaign (www.choosingwisely.org).

HARMS ASSOCIATED WITH SPINE IMAGING

Several guidelines cite radiation exposure as a potential harmful consequence of spinal imaging by plain radiography and computed tomography. The American College of Radiology guideline⁴ estimates that the radiation exposure of plain lumbar radiography or lumbar computed tomography ranges between 1 and 10 mSv (3 mSv is the annual amount of ambient radiation in the United States), placing both studies in the medium-range category for relative radiation exposure. The ACP/APS guideline⁵ states that radiation exposure from imaging is a reason to dissuade clinicians from routine use.

Although lumbar magnetic resonance imaging does not carry the risk of radiation exposure, it may result in harm by detecting clinically insignificant abnormalities in more than 30% of patients.⁷ These incidental findings increase with age and may lead to additional and possibly unnecessary testing and invasive treatments. The American College of Occupational and Environmental Medicine guideline⁶ also cites the high prevalence of abnormal findings on plain radiography, magnetic resonance imaging, and other diagnostic tests that are unrelated to symptoms.

CLINICAL BOTTOM LINE

On the basis of current data, the patient described at the beginning of this article should not undergo spine imaging; the results are unlikely to affect his medical management and improve his clinical outcome, and imaging carries a small risk of harm.

A practical approach would be to treat his pain with simple analgesia (a different nonsteroidal anti-inflammatory drug or acetaminophen), address his functional challenges, and reassure him that his chance of having a serious underlying cause of back pain is low (< 1%). He should be told to expect significant improvement in his symptoms within 30 days, be encouraged to stay active, and should be offered patient-focused self-help resources.

The recommendation to conservatively manage patients at low risk without imaging is consistent among all four guidelines. Imaging can be considered for a small subset of patients at high risk with red-flag indications. Potential harms associated with routine imaging of all patients with low back pain include radiation exposure and the high rate of clinically insignificant abnormalities that may lead to unnecessary and invasive interventions that increase expense, patient risk, and anxiety without improving outcomes.

A 48-year-old insurance executive is offered the option of several health insurance packages at the time of a promotion. He is healthy and a non-smoker; both his parents are alive and well; and he takes only vitamins and fish oil supplements on a regular basis. His levels of total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol are all in the normal range, as is his blood pressure. He plans to purchase the lowest price policy, but wants to know if he should also get a stress test to best guide his care.

GUIDELINES RECOMMEND AGAINST TESTING

Patients who are at low risk of disease and without symptoms should not undergo cardiac stress testing. The test is unlikely to be helpful in these patients and may expose them to harm unnecessarily. Cardiac stress testing such as exercise electrocardiography is most useful in patients who have chest pain and shortness of breath on exertion, to look for underlying cardiovascular disease. Despite this, the test is often used inappropriately as part of a routine health evaluation in low-risk, asymptomatic people, such as this patient.

Recent high-quality guidelines address exercise electrocardiography as a screening test for cardiovascular disease in asymptomatic, low-risk adults.

The US Preventive Services Task Force 2012 guideline¹ recommends against screening with exercise electrocardiography for predicting coronary heart disease events in adults with no symptoms and at low risk of these events. A systematic review found no data from randomized controlled trials or prospective cohort studies of this test to screen asymptomatic adults compared with no screening.²

The American Academy of Family Physicians (AAFP) 2012 guideline³ recommends against routine screening with exercise electrocardiography either for the presence of severe coronary artery stenosis or for predicting coronary events in adults at low risk. The AAFP guideline notes that there is moderate or high certainty of no net benefit or that the harms outweigh the benefits of exercise electrocardiography in adults at low risk and without symptoms.

The 2010 joint guideline of the American College of Cardiology and the American Heart Association⁴ does not comment on the role of screening exercise electrocardiography in low-risk asymptomatic adults, but states that a physician may consider ordering exercise electrocardiography in asymptomatic adults at intermediate risk of coronary heart disease. The guideline recommends that the individual physician decide whether screening exercise electrocardiography is warranted in a patient at intermediate risk.

The Choosing Wisely initiative

As part of the Choosing Wisely initiative of the American Board of Internal Medicine Foundation, a number of medical specialty societies have published lists of recommendations and issues that physicians and patients should question and discuss. Cardiac stress testing in low-risk asymptomatic patients is on the list of a number of organizations, including the American College of Physicians, the American College of Cardiology, the AAFP, and the American Society of Nuclear Cardiology. These lists can be found at www.choosingwisely.org.

POSSIBLE HARM ASSOCIATED WITH CARDIAC STRESS TESTING

The overall risk of sudden cardiac death or an event that requires hospitalization during exercise electrocardiography is very small, estimated to be 1 per 10,000 tests, and the risk is probably even less in patients at low risk.⁵ But the risk of potential downstream harm from additional testing or interventions may be greater than direct harm. Still, no study has yet assessed harm associated with follow-up testing or interventions after screening with exercise electrocardiography.

On the basis of large, population-based registries that include symptomatic persons, the risk of any serious adverse event as a result of angiography is about 1.7%; this includes a 0.1% risk of death, a 0.05% risk of myocardial infarction, a 0.07% risk of stroke, and a 0.4% risk of arrhythmia.⁶ In addition, coronary angiography is associated with an average effective radiation dose of 7 mSv and myocardial perfusion imaging with a dose of 15.6 mSv.⁷ These are approximately two times and five times the amount of radiation an average person in the United States receives per year from exposure to ambient radiation (3 mSv).

Several studies that included symptomatic and asymptomatic patients who had undergone angiography reported that between 39% and 85% of patients had no coronary artery disease. This means that many patients were subjected to the risks of invasive testing and treatment without the possibility of benefit. Patients who receive lipid-lowering therapy or aspirin because of an abnormal exercise electrocardiogram are also exposed to the risks related to those interventions.

THE CLINICAL BOTTOM LINE

On the basis of current data, the insurance executive should not get a stress test because the results of the test are unlikely to have an impact on his medical management, are unlikely to improve his clinical outcome, and carry a small risk of harm. Low-risk, asymptomatic people with a positive stress test have the same mortality rate as those who have a negative stress test, and its usefulness beyond traditional risk-factor assessment in motivating patients and guiding therapy has not been established.⁸ In addition, the rate of false-positive results with exercise stress testing is as high as 71%.⁹ Although the risk of an adverse event from the initial stress test is low, ie, 1 serious event in 10,000 tests, the risk of subsequent cardiac catheterization after a positive test is significantly higher, ie, 170 serious events in 10,000 tests. For these reasons, the potential harm of exercise electrocardiography outweighs the benefits in this patient.

A 48-year-old insurance executive is offered the option of several health insurance packages at the time of a promotion. He is healthy and a non-smoker; both his parents are alive and well; and he takes only vitamins and fish oil supplements on a regular basis. His levels of total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol are all in the normal range, as is his blood pressure. He plans to purchase the lowest price policy, but wants to know if he should also get a stress test to best guide his care.

GUIDELINES RECOMMEND AGAINST TESTING

Patients who are at low risk of disease and without symptoms should not undergo cardiac stress testing. The test is unlikely to be helpful in these patients and may expose them to harm unnecessarily. Cardiac stress testing such as exercise electrocardiography is most useful in patients who have chest pain and shortness of breath on exertion, to look for underlying cardiovascular disease. Despite this, the test is often used inappropriately as part of a routine health evaluation in low-risk, asymptomatic people, such as this patient.

Recent high-quality guidelines address exercise electrocardiography as a screening test for cardiovascular disease in asymptomatic, low-risk adults.

The US Preventive Services Task Force 2012 guideline¹ recommends against screening with exercise electrocardiography for predicting coronary heart disease events in adults with no symptoms and at low risk of these events. A systematic review found no data from randomized controlled trials or prospective cohort studies of this test to screen asymptomatic adults compared with no screening.²

The American Academy of Family Physicians (AAFP) 2012 guideline³ recommends against routine screening with exercise electrocardiography either for the presence of severe coronary artery stenosis or for predicting coronary events in adults at low risk. The AAFP guideline notes that there is moderate or high certainty of no net benefit or that the harms outweigh the benefits of exercise electrocardiography in adults at low risk and without symptoms.

The 2010 joint guideline of the American College of Cardiology and the American Heart Association⁴ does not comment on the role of screening exercise electrocardiography in low-risk asymptomatic adults, but states that a physician may consider ordering exercise electrocardiography in asymptomatic adults at intermediate risk of coronary heart disease. The guideline recommends that the individual physician decide whether screening exercise electrocardiography is warranted in a patient at intermediate risk.

The Choosing Wisely initiative

As part of the Choosing Wisely initiative of the American Board of Internal Medicine Foundation, a number of medical specialty societies have published lists of recommendations and issues that physicians and patients should question and discuss. Cardiac stress testing in low-risk asymptomatic patients is on the list of a number of organizations, including the American College of Physicians, the American College of Cardiology, the AAFP, and the American Society of Nuclear Cardiology. These lists can be found at www.choosingwisely.org.

POSSIBLE HARM ASSOCIATED WITH CARDIAC STRESS TESTING

The overall risk of sudden cardiac death or an event that requires hospitalization during exercise electrocardiography is very small, estimated to be 1 per 10,000 tests, and the risk is probably even less in patients at low risk.⁵ But the risk of potential downstream harm from additional testing or interventions may be greater than direct harm. Still, no study has yet assessed harm associated with follow-up testing or interventions after screening with exercise electrocardiography.

On the basis of large, population-based registries that include symptomatic persons, the risk of any serious adverse event as a result of angiography is about 1.7%; this includes a 0.1% risk of death, a 0.05% risk of myocardial infarction, a 0.07% risk of stroke, and a 0.4% risk of arrhythmia.⁶ In addition, coronary angiography is associated with an average effective radiation dose of 7 mSv and myocardial perfusion imaging with a dose of 15.6 mSv.⁷ These are approximately two times and five times the amount of radiation an average person in the United States receives per year from exposure to ambient radiation (3 mSv).

Several studies that included symptomatic and asymptomatic patients who had undergone angiography reported that between 39% and 85% of patients had no coronary artery disease. This means that many patients were subjected to the risks of invasive testing and treatment without the possibility of benefit. Patients who receive lipid-lowering therapy or aspirin because of an abnormal exercise electrocardiogram are also exposed to the risks related to those interventions.

THE CLINICAL BOTTOM LINE

On the basis of current data, the insurance executive should not get a stress test because the results of the test are unlikely to have an impact on his medical management, are unlikely to improve his clinical outcome, and carry a small risk of harm. Low-risk, asymptomatic people with a positive stress test have the same mortality rate as those who have a negative stress test, and its usefulness beyond traditional risk-factor assessment in motivating patients and guiding therapy has not been established.⁸ In addition, the rate of false-positive results with exercise stress testing is as high as 71%.⁹ Although the risk of an adverse event from the initial stress test is low, ie, 1 serious event in 10,000 tests, the risk of subsequent cardiac catheterization after a positive test is significantly higher, ie, 170 serious events in 10,000 tests. For these reasons, the potential harm of exercise electrocardiography outweighs the benefits in this patient.

A 48-year-old insurance executive is offered the option of several health insurance packages at the time of a promotion. He is healthy and a non-smoker; both his parents are alive and well; and he takes only vitamins and fish oil supplements on a regular basis. His levels of total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol are all in the normal range, as is his blood pressure. He plans to purchase the lowest price policy, but wants to know if he should also get a stress test to best guide his care.

GUIDELINES RECOMMEND AGAINST TESTING

Patients who are at low risk of disease and without symptoms should not undergo cardiac stress testing. The test is unlikely to be helpful in these patients and may expose them to harm unnecessarily. Cardiac stress testing such as exercise electrocardiography is most useful in patients who have chest pain and shortness of breath on exertion, to look for underlying cardiovascular disease. Despite this, the test is often used inappropriately as part of a routine health evaluation in low-risk, asymptomatic people, such as this patient.

Recent high-quality guidelines address exercise electrocardiography as a screening test for cardiovascular disease in asymptomatic, low-risk adults.

The US Preventive Services Task Force 2012 guideline¹ recommends against screening with exercise electrocardiography for predicting coronary heart disease events in adults with no symptoms and at low risk of these events. A systematic review found no data from randomized controlled trials or prospective cohort studies of this test to screen asymptomatic adults compared with no screening.²

The American Academy of Family Physicians (AAFP) 2012 guideline³ recommends against routine screening with exercise electrocardiography either for the presence of severe coronary artery stenosis or for predicting coronary events in adults at low risk. The AAFP guideline notes that there is moderate or high certainty of no net benefit or that the harms outweigh the benefits of exercise electrocardiography in adults at low risk and without symptoms.

The 2010 joint guideline of the American College of Cardiology and the American Heart Association⁴ does not comment on the role of screening exercise electrocardiography in low-risk asymptomatic adults, but states that a physician may consider ordering exercise electrocardiography in asymptomatic adults at intermediate risk of coronary heart disease. The guideline recommends that the individual physician decide whether screening exercise electrocardiography is warranted in a patient at intermediate risk.

The Choosing Wisely initiative

As part of the Choosing Wisely initiative of the American Board of Internal Medicine Foundation, a number of medical specialty societies have published lists of recommendations and issues that physicians and patients should question and discuss. Cardiac stress testing in low-risk asymptomatic patients is on the list of a number of organizations, including the American College of Physicians, the American College of Cardiology, the AAFP, and the American Society of Nuclear Cardiology. These lists can be found at www.choosingwisely.org.

POSSIBLE HARM ASSOCIATED WITH CARDIAC STRESS TESTING

The overall risk of sudden cardiac death or an event that requires hospitalization during exercise electrocardiography is very small, estimated to be 1 per 10,000 tests, and the risk is probably even less in patients at low risk.⁵ But the risk of potential downstream harm from additional testing or interventions may be greater than direct harm. Still, no study has yet assessed harm associated with follow-up testing or interventions after screening with exercise electrocardiography.

On the basis of large, population-based registries that include symptomatic persons, the risk of any serious adverse event as a result of angiography is about 1.7%; this includes a 0.1% risk of death, a 0.05% risk of myocardial infarction, a 0.07% risk of stroke, and a 0.4% risk of arrhythmia.⁶ In addition, coronary angiography is associated with an average effective radiation dose of 7 mSv and myocardial perfusion imaging with a dose of 15.6 mSv.⁷ These are approximately two times and five times the amount of radiation an average person in the United States receives per year from exposure to ambient radiation (3 mSv).

Several studies that included symptomatic and asymptomatic patients who had undergone angiography reported that between 39% and 85% of patients had no coronary artery disease. This means that many patients were subjected to the risks of invasive testing and treatment without the possibility of benefit. Patients who receive lipid-lowering therapy or aspirin because of an abnormal exercise electrocardiogram are also exposed to the risks related to those interventions.

THE CLINICAL BOTTOM LINE

On the basis of current data, the insurance executive should not get a stress test because the results of the test are unlikely to have an impact on his medical management, are unlikely to improve his clinical outcome, and carry a small risk of harm. Low-risk, asymptomatic people with a positive stress test have the same mortality rate as those who have a negative stress test, and its usefulness beyond traditional risk-factor assessment in motivating patients and guiding therapy has not been established.⁸ In addition, the rate of false-positive results with exercise stress testing is as high as 71%.⁹ Although the risk of an adverse event from the initial stress test is low, ie, 1 serious event in 10,000 tests, the risk of subsequent cardiac catheterization after a positive test is significantly higher, ie, 170 serious events in 10,000 tests. For these reasons, the potential harm of exercise electrocardiography outweighs the benefits in this patient.