Clinician-dependent variations in inappropriate use of myocardial perfusion imaging: training, specialty, and location

Association of State Share of Nonphysician Practitioners With Diagnostic Imaging Ordering Among Emergency Department Visits for Medicare Beneficiaries

IMPORTANCE

The use of nonphysician practitioners (NPPs) in the emergency department (ED) continues to expand, yet little is known about associations between NPPs and ED imaging use.

OBJECTIVE

To investigate whether the state share of ED visits for which an NPP was the clinician of record is associated with imaging studies ordered, given that state NPP share is associated with state-level NPP scopes of practice.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study compared diagnostic imaging ordering patterns associated with ED visits based on 2005-2020 Medicare claims for a nationally representative 5% sample of fee-for-service beneficiaries. For all 50 states and the District of Columbia, the state NPP share of ED visits by year was used to represent state-specific practice patterns for NPPs and physicians and how those patterns have evolved over time. The analysis controlled for patient demographic characteristics, Charlson Comorbidity Index scores, ED visit severity, year, and principal diagnosis.

EXPOSURES

The share of ED visits in each state in each year (state share) for which an NPP was the evaluation and management clinician.

MAIN OUTCOMES AND MEASURES

The main outcomes were the number and modality of imaging studies associated with ED visits. Analyses were by logistic regression and generalized linear model with γ-distribution and log-link function.

RESULTS

Among 16 922 274 ED visits, 60.0% involved women, and patients' mean (SD) age was 70.3 (16.1) years. The share of all ED visits with an NPP as the clinician increased from 6.1% in 2005 to 16.6% in 2020. Compared with no NPPs, the presence of NPPs in the ED was associated with 5.3% (95% CI, 5.1%-5.5%) more imaging studies per ED visit, including a 3.4% (95% CI, 3.2%-3.5%) greater likelihood of any imaging order per ED visit and 2.2% (95% CI, 2.0%-2.3%) more imaging studies ordered per visit involving imaging.

CONCLUSIONS AND RELEVANCE

In this study, use of NPPs in the ED was associated with higher imaging use compared with the use of only physicians in the ED. Although expanded use of NPPs in the ED may improve patient access, the costs and radiation exposure associated with more imaging warrants additional study.

Effect of Elevated Calcium Score on Normal Myocardial Perfusion Study on Clinician Management of Coronary Artery Disease Risk Factors

Elevated coronary artery calcification (CAC) scores are associated with higher cardiovascular (CV) risk even with normal stress myocardial perfusion imaging (MPI). Whether referring providers appropriately manage subclinical CV disease is unclear. We hypothesized that ordering clinicians would intensify medical therapy for CV disease in response to normal MPI and CAC ≥ 300. We conducted a cohort study on patients without known CV disease who underwent MPI and CAC scoring. Medical management of CV disease and clinical outcomes were assessed. Of 299 patients who underwent stress MPI, 62 patients had normal MPI and CAC ≥ 300. Documentation of elevated CAC score was noted in the final interpretation for 52% (n = 32) of MPI reports. During follow-up, treatment change in aspirin, cholesterol medications, and/or antihypertensive medication was made in 40% of these patients. Aspirin use increased from 71% to 82% (P < 0.001); statin use increased from 68% to 76% (P < 0.001). Several patients remained on suboptimal lipid or antiplatelet regimens without documented contraindication. Among patients with normal MPI, many have CAC ≥ 300. Not all MPI reports adequately call attention to this finding associated with elevated CV risk. Despite the elevated CAC score, some patients were not optimized medically.

Addressing unwarranted clinical variation: A rapid review of current evidence

INTRODUCTION

Unwarranted clinical variation (UCV) can be described as variation that can only be explained by differences in health system performance. There is a lack of clarity regarding how to define and identify UCV and, once identified, to determine whether it is sufficiently problematic to warrant action. As such, the implementation of systemic approaches to reducing UCV is challenging. A review of approaches to understand, identify, and address UCV was undertaken to determine how conceptual and theoretical frameworks currently attempt to define UCV, the approaches used to identify UCV, and the evidence of their effectiveness.

DESIGN

Rapid evidence assessment (REA) methodology was used.

DATA SOURCES

A range of text words, synonyms, and subject headings were developed for the major concepts of unwarranted clinical variation, standards (and deviation from these standards), and health care environment. Two electronic databases (Medline and Pubmed) were searched from January 2006 to April 2017, in addition to hand searching of relevant journals, reference lists, and grey literature.

DATA SYNTHESIS

Results were merged using reference-management software (Endnote) and duplicates removed. Inclusion criteria were independently applied to potentially relevant articles by 3 reviewers. Findings were presented in a narrative synthesis to highlight key concepts addressed in the published literature.

RESULTS

A total of 48 relevant publications were included in the review; 21 articles were identified as eligible from the database search, 4 from hand searching published work and 23 from the grey literature. The search process highlighted the voluminous literature reporting clinical variation internationally; yet, there is a dearth of evidence regarding systematic approaches to identifying or addressing UCV.

CONCLUSION

Wennberg's classification framework is commonly cited in relation to classifying variation, but no single approach is agreed upon to systematically explore and address UCV. The instances of UCV that warrant investigation and action are largely determined at a systems level currently, and stakeholder engagement in this process is limited. Lack of consensus on an evidence-based definition for UCV remains a substantial barrier to progress in this field.

Perceptions of patients and providers on myocardial perfusion imaging for asymptomatic patients, choosing wisely, and professional liability

Background

Despite efforts by professional societies to reduce low value care, many reports indicate that unnecessary tests, such as nuclear myocardial perfusion imaging (MPI), are commonly used in contemporary practice. The degree to which lack of awareness and professional liability concerns drive these behaviors warrants further study. We sought to investigate patient and provider perceptions about MPI in asymptomatic patients, the Choosing Wisely (CW) campaign, and professional liability concerns.

Methods

We administered an anonymous, paper-based survey with both discrete and open-response queries to subjects in multiple outpatient settings at our facilities. The survey was completed by 456 respondents including 342 patients and 114 physicians and advanced practice providers between May and August 2014. Our outcome was to compare patient and provider perceptions about MPI in asymptomatic patients and related factors.

Results

Patients were more likely than providers to report that MPI was justified for asymptomatic patients (e.g. asymptomatic with family history of heart disease 75% versus 9.2%, p < 0.0001). In free responses to the question “What would be an inappropriate reason for MPI?” many responses echoed the goals of CW (for example, “If you don’t have symptoms”, “If the test is too risky”, “For screening or in asymptomatic patients”). A minority of providers were aware of CW while even fewer patients were aware (37.2% versus 2.7%, p < 0.0001). Over one third of providers (38.9%) admitted to ordering MPI out of concern for professional liability including 48.3% of VA affiliated providers.

Conclusions

While some patients and providers are aware of the low value of MPI in patients without symptoms, others are enthusiastic to use it for a variety of scenarios. Concerns about professional liability likely contribute, even in the VA setting. Awareness of the Choosing Wisely campaign is low in both groups.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-017-2510-y) contains supplementary material, which is available to authorized users.

Comparison of the Appropriateness of Myocardial Perfusion Imaging in Men Versus Women

After a decade of appropriate use criteria publication, the degree and predictors of inappropriate use in women compared with men are not known. We conducted a retrospective cohort investigation comparing appropriateness categories (appropriate, maybe appropriate, and rarely appropriate) and cardiovascular outcomes in patients undergoing nuclear myocardial perfusion imaging (MPI) between June 2011 and September 2014 in predominantly inpatient setting. Of 1,475 cases reviewed, 747 (50.6%) were women, and they were more likely to have rarely appropriate use 118 (15.8%) than men 62 (8.5%), p <0.01, but they were less likely to have an abnormal MPI 102 (13.6%) than men 183 (25.6%), p <0.01. Subsequent angiography and revascularization rates were similar in women 38 (37.2%) and 5 (4.9%) and men 52 (28.4%) and 16 (8.7%), p = 0.12, p = 0.23, respectively. After median follow-up of 6 months, myocardial infarction rates were similar in women 3 (2.9%) and men 7 (3.8%), p = 0.67. Death rates were similar in women 8 (7.8%) and men 18 (9.8%), p = 0.57. The most common clinical scenario designated as rarely appropriate was in those with low pretest probability of coronary artery disease, who have interpretable electrocardiogram and are able to exercise in women 58 (49.1%) and men 21 (33.8%). In conclusion, based on the most contemporary appropriate use criteria publication, rarely appropriate use of MPI remains higher in women than that in men. This phenomenon was mostly observed in low-risk patients who can exercise.

A specialty-specific, multimodality educational quality improvement initiative to deimplement rarely appropriate myocardial perfusion imaging

Objective

Investigations of Appropriate Use Criteria (AUC) education have shown a mixed effect on changing provider behaviour. At our facility, rarely appropriate myocardial perfusion imaging (MPI) differs by specialty; awareness of AUC is low. Our objective is to investigate if specialty-specific, multimodality education could reduce rarely appropriate MPI.

Methods

We designed education focused on the rarely appropriate MPI ordered most often by each specialty. We tracked appropriateness of MPI in three cohorts: pre, post (immediately after) and late-post (4 months after) intervention.

Results

A total of 889 MPI were evaluated (n=287 pre, n=313 post, n=289 late-post), 95.3% were men. Chest pain was the most common symptom (n=530, 59.6%), while 14.1% (n=125) had no symptoms. Rarely appropriate testing decreased from 4.9% to 1.3% and remained at 1.4% in the late-post cohort (p<0.0001). In logistic regression, lack of symptoms (OR 31.3, 95% CI 10.3 to 94.8, p≤0.0001) and being in the post or late-post cohorts (OR 0.27, 95% CI 0.11 to 0.68, p=0.006) were associated with rarely appropriate MPI. Preoperative MPI in patients with good exercise capacity was a common rarely appropriate indication. Ischaemia was not observed among patients with rarely appropriate indication for MPI.

Conclusions

In certain clinical settings, education may be an effective approach for deimplementing rarely appropriate MPI. The effect of education may be enhanced when focused on improving patient care, delivered by a peer, and needs assessment indicates low awareness of guidelines. Lack of symptoms and preoperative MPI continue to be the predominant rarely appropriate MPI ordered.

Appropriate Use of Cardiac Stress Testing with Imaging: A Systematic Review and Meta-Analysis

BACKGROUND

Appropriate use criteria (AUC) for cardiac stress tests address concerns about utilization growth and patient safety. We systematically reviewed studies of appropriateness, including within physician specialties; evaluated trends over time and in response to AUC updates; and characterized leading indications for inappropriate/rarely appropriate testing.

METHODS

We searched PubMed (2005-2015) for English-language articles reporting stress echocardiography or myocardial perfusion imaging (MPI) appropriateness. Data were pooled using random-effects meta-analysis and meta-regression.

RESULTS

Thirty-four publications of 41,578 patients were included, primarily from academic centers. Stress echocardiography appropriate testing rates were 53.0% (95% CI, 45.3%-60.7%) and 50.9% (42.6%-59.2%) and inappropriate/rarely appropriate rates were 19.1% (11.4%-26.8%) and 28.4% (23.9%-32.8%) using 2008 and 2011 AUC, respectively. Stress MPI appropriate testing rates were 71.1% (64.5%-77.7%) and 72.0% (67.6%-76.3%) and inappropriate/rarely appropriate rates were 10.7% (7.2%-14.2%) and 15.7% (12.4%-19.1%) using 2005 and 2009 AUC, respectively. There was no significant temporal trend toward rising rates of appropriateness for stress echocardiography or MPI. Unclassified stress echocardiograms fell by 79% (p = 0.04) with updated AUC. There were no differences between cardiac specialists and internists.

CONCLUSIONS

Rates of appropriate use tend to be lower for stress echocardiography compared to MPI, and updated AUC reduced unclassified stress echocardiograms. There is no conclusive evidence that AUC improved appropriate use over time. Further research is needed to determine if integration of appropriateness guidelines in academic and community settings is an effective approach to optimizing inappropriate/rarely appropriate use of stress testing and its associated costs and patient harms.

Outcomes after inappropriate nuclear myocardial perfusion imaging: A meta-analysis

BACKGROUND

The relationship between inappropriate MPI and cardiovascular outcomes is poorly understood. We sought to systematically review the literature on appropriate use criteria (AUC) for MPI, including temporal trend of inappropriate testing and resulting cardiovascular outcomes.

METHODS

We searched the MEDLINE database for studies related to AUC and MPI. The co-primary outcomes were abnormal test results and the presence of cardiac ischemia. Random effects odds ratios (OR) were constructed using DerSimonian-Laird method.

RESULTS

A total of 22 studies with 23,443 patients were included. The prevalence of inappropriate testing was 14.8% [95% confidence interval (CI) 11.6%-18.7%]. Inappropriate MPI studies were less likely to be abnormal (OR 0.41 95% CI 0.35-0.49, P < .0001) and to demonstrate ischemia (OR 0.40, 95% CI 0.24-0.67, P < .0001) compared to appropriate testing. No difference in the rate of inappropriate tests was detected based on the midpoint of the enrollment year (P = .54). The pattern of ordering inappropriate studies was not different between cardiology and non-cardiology providers (OR 0.74, 95% CI 0.51-1.06, P = .10).

CONCLUSION

Inappropriate MPI studies are less likely to yield abnormal results or demonstrate myocardial ischemia. The rate of inappropriate MPI has not decreased over time.

Review of cardiovascular imaging in The Journal of Nuclear Cardiology in 2014: Part 2 of 2: Myocardial perfusion imaging

In this new feature of The Journal of Nuclear Cardiology we will summarize key articles that were published in the Journal in the previous year. In the first article of this 2-part series we concentrated on publications dealing with cardiac positron emission tomography, computed tomography, and neuronal imaging. This review will focus on myocardial perfusion imaging summarizing advances in the field including in diagnosis, prognosis, appropriateness, and safety of testing.

Metrics of quality care in veterans: correlation between primary-care performance measures and inappropriate myocardial perfusion imaging

BACKGROUND

Approximately 10% to 20% of myocardial perfusion imaging (MPI) tests are inappropriate based on professional-society recommendations. The correlation between inappropriate MPI and quality care metrics is not known.

HYPOTHESIS

Inappropriate MPI will be associated with low achievement of quality care metrics.

METHODS

We conducted a retrospective cross-sectional investigation at a single Veterans Affairs medical center. Myocardial perfusion imaging tests ordered by primary-care clinicians between December 2010 and July 2011 were assessed for appropriateness (by 2009 criteria). Using documentation of the clinical encounter where MPI was ordered, we determined how often quality care metrics were achieved.

RESULTS

Among 516 MPI patients, 52 (10.1%) were inappropriate and 464 (89.9%) were not inappropriate (either appropriate or uncertain). Hypertension (82.2%), diabetes mellitus (41.3%), and coronary artery disease (41.1%) were common. Glycated hemoglobin levels were lower in the inappropriate MPI cohort (6.6% vs 7.5%; P = 0.04). No difference was observed in the proportion with goal hemoglobin (62.5% vs 46.3% for appropriate/uncertain; P = 0.258). Systolic blood pressure was not different (132 mm Hg vs 135 mm Hg; P = 0.34). Achievement of several other categorical quality metrics was low in both cohorts and no differences were observed. More than 90% of clinicians documented a plan to achieve most metrics.

CONCLUSIONS

Inappropriate MPI is not associated with performance on metrics of quality care. If an association exists, it may be between inappropriate MPI and overly aggressive care. Most clinicians document a plan of care to address failure of quality metrics, suggesting awareness of the problem.