Stability in Cardiac Attributions Before and After Cardiac Rehabilitation

Kymberley K. Bennett, PhD, Kadie M. Harry, MA, Kalon R. Eways, MA, Elizabeth J. Wilson, BA, Jillian M.R. Clark, PhD, Alisha D. Howarter, MA & Tamera B. Murdock, PhD

Journal of the American Association of Nurse Practitioners


Abstract

Purpose This study examined temporal patterns in causal attributions generated by patients with cardiovascular disease before and after cardiacrehabilitation (CR).

Design Qualitative, descriptive survey.

Methods Eighty-six participants were asked what they believed was the primary cause of their cardiac events. Cardiac attributions were collected at the beginning of CR, at the end of CR, and 15 months after baseline.

Findings Content analyses showed that heredity and behavior were the most commonly generated causes. Most participants showed stability in attributions over time, although we found a trend for more participants endorsing behavioral attributions at the end of the study.

Conclusions Cardiac attributions remain relatively stable across time.

Clinical Relevance Cardiac rehabilitation staff should approach patients differently, depending on their causal narratives. Some patients enter CR understanding that behavior played a causal role, whereas some do not. Encouraging appreciation of the importance of behavior in cardiovascular disease onset and recurrence is vital.


Cognitive adaptation theory (Taylor, 1983) suggests that creating meaning following a threatening event is important for adjustment. For most people, meaning creation comes from the generation of a causal attribution. For patients with cardiovascular disease (CVD), the causal narrative answers the question: “Why did I experience this cardiac event or CVD diagnosis?” Indeed, researchers have found that most patients create one or more attributions about the origins of their CVD (Bennett & Marte, 2013). Taylor (1983) suggests that meaning lends itself to perceived control and that over time perceived control aids adjustment. Several studies have examined the types of attributions patients with CVD create, some using checklist-type methods (Cameron, Petrie, Ellis, Buick, & Weinman, 2005 Day, Freedland, & Carney, 2005 Dunkel, Kendel, Lehmkuhl, Hetzer, & Regitz-Zagrosek, 2011 Reges et al., 2011 Stafford, Jackson, & Berk, 2008) and others using qualitative approaches (Astin & Jones, 2004 Bennett, Clark, Harry, & Howarter, 2016 Bennett & Marte, 2013 Darr, Astin, & Atkin, 2008 French, Maissi, & Marteau, 2005 Martin et al., 2005 Richards, Reid, & Watt, 2003). Research also has examined effects of attributions on cardiac health outcomes, but only three studies have tested their temporal patterns (Affleck, Tennen, Croog, & Levine, 1987 Cameron et al., 2005 Reges et al., 2011). Of note, no studies of which we are aware have examined temporal patterns using a qualitative approach, and that is the purpose of this study.

Common Themes of Cardiac Attributions

Studies using a checklist method often ask patients with CVD to endorse causes that they believe contributed to disease onset from an established list of possibilities. Many of these causes break down into behavioral ones and biological ones. For example, Cameron et al. (2005) sampled patients with myocardial infarction (MI) shortly after diagnosis and found that the most commonly endorsed causes were stress, high cholesterol, heredity, poor diet, and hypertension; a similar study of patients with MI reported smoking, stress, and heredity as the most commonly endorsed causes (Reges et al., 2011). Other studies report a mix of behavioral and biological causes endorsed by patients with CVD (Dunkel et al., 2011 Stafford et al., 2008). In addition, one study found that patients with heart disease experiencing anxiety or depressive symptoms were more likely than their nondistressed counterparts to endorse negative emotion attributions such as stress, anger, sadness, nervousness, fear, and loneliness (Day et al., 2005). Studies also suggest a socioeconomic status (SES) difference for endorsement of heredity as a causal factor: highly educated patients with acute coronary syndrome (Perkins-Porras, Whitehead, & Steptoe, 2006) and patients with MI categorized as high in social class (Affleck et al., 1987) were more likely to endorse heredity compared to their counterparts.

The other means of measuring attributions comes from asking participants open-ended questions, allowing them to generate causal narratives in their own words. This method has been used by several researchers and has yielded three overarching themes similar to checklist methods: behavioral causes, biological causes, and stressors (Bennett et al., 2016 Bennett & Marte, 2013 Darr et al., 2008 French et al., 2005 Richards et al., 2003). For example, Martin et al. (2005) content analyzed attributions generated by patients with MI and found the following common themes: stress, comorbidities, heredity, diet, smoking, and physical inactivity. They also noted a gender difference: Men were more likely to create a behavioral attribution than women; 3 months later, men were more likely to self-report improvements in diet and exercise than women. These themes and gender differences were also reported by Astin and Jones (2004), with men more likely to generate a behavioral cause than women and women more likely to generate a biological cause than men.

Cardiac Attributions as Predictors of Outcomes

Studies also have examined cardiac attributions as predictors of health outcomes, with most suggesting protective effects of behavioral attributions on health. Martin et al. (2005) found that creating behavioral attributions was linked to self-reported gains in parallel domains 3 months later; for example, most patients who attributed their MIs to dietary factors made self-reported gains in diet at follow-up. Blair et al. (2014)found that patients who created behavioral attributions following hospitalization were more likely to attend cardiac rehabilitation (CR) than their counterparts who did not create a behavioral attribution. An intervention study by Broadbent, Ellis, Thomas, Gamble, and Petrie (2009) to encourage behavioral attributions post-MI found that the intervention group was significantly more likely to return to work at the 3-month follow-up and to self-report gains in exercise at the 3- and 6-month follow-ups, compared to their control group counterparts. Bennett et al. (2016) reported that patients in CR who created a behavioral attribution at the beginning of CR had concurrently higher perceived control than patients who did not create a behavioral attribution, but they also had higher anxiety symptoms 21 months later. Research is mixed with regard to the health effects of stress attributions. For example, Dunkel et al. (2011) showed that stress and personality attributions by patients with coronary artery bypass graft were associated with an increase in depressive symptoms 1 year later, after controlling for demographic and clinical factors. However, another study found that creating a stress attribution was predictive of an increase in functional capacity among patients in CR (Bennett & Marte, 2013).

Temporal Patterns of Cardiac Attributions

To date, limited research has tested temporal patterns of cardiac attributions, the focus of the current study. Using a checklist method, Affleck et al. (1987) asked patients 7 weeks and 1 year post-MI what caused their cardiac events. At both times, stress was the most commonly endorsed cause, followed by their own behavior. These authors calculated correlations between scores on the causal checklists at Times 1 and 2. Results showed high degrees of stability: The correlation between stress attributions was .57 (p < .001), and the correlation between past behaviors was .56 (p < .001). Thus, Affleck et al. concluded that cardiac attributions remained relatively stable over the year following an MI. Likewise, Cameron et al. (2005)assessed the stability of causal endorsements on a checklist at hospital admission for MI, at hospital discharge and 3 and 6 months later. Repeated measures ANOVAs revealed no differences across the four data collection times for any of the five main causal themes. Thus, again, results suggest a moderate degree of stability in the narratives patients create following a cardiac event.

Reges et al. (2011) examined the stability of causal attributions by patients with MI using a checklist method, comparing endorsements of 13 potential causes during hospitalization to endorsements made approximately 2 years later. Results showed stability in 9 of the 13 causes across time. However, patients made significantly more endorsements to the following causes at follow-up compared to baseline: hyperlipidemia (33.1% vs. 7.9%), sedentary lifestyle (24.2% vs. 5.6%), heredity (33.1% vs. 16.3%), and work stressors (32.0% vs. 10.7%). Furthermore, participants who completed a CR program were more likely to increase their endorsement of sedentary lifestyle as a cause from baseline to follow-up compared to patients who did not participate in a CR program. Thus, all three studies that have examined temporal patterns in cardiac attributions show moderate stability. The one study (Reges et al., 2011) with evidence of change across time used a longer follow-up period and suggested an interesting effect of participating in a CR program: a strengthening over time of the recognition of lack of physical activity as a risk factor for CVD onset. Notably, we were unable to find any studies that have used a qualitative approach to examine temporal patterns of cardiac attributions.

 

Diagnostics

There are multiple tests that can lead clinicians to identify TCM as the principle diagnosis. Such tests include electrocardiography (EKG), laboratory biomarkers, echocardiogram, left ventriculography, cardiac magnetic resonance imaging (MRI), and angiography. Each test is discussed in the following section.

Electrocardiography findings

The various EKG findings associated with TCM are not diagnostic but are often characterized by evolutionary changes. An ST segment elevation at the beginning of this syndrome can be seen primarily in the precordial leads in approximately 50% of patients. Unlike an AMI, reciprocal ST-segment depression in the inferior wall leads is unusual. Inverted T waves are frequently seen in patients with the apical balloon-like dilation and normalize spontaneously within a few weeks to several months. In addition, patients with TCM usually show abnormal Q waves in precordial leads. Unlike infarction-induced Q waves, these Q waves are transient in most patients and generally resolve within a few days to several weeks (Scantlebury & Prasad, 2014).

Biomarkers

The clinician should ensure that blood samples are obtained for cardiac enzymes, every 8 hours during the first 24 hours after hospital admission, every 12 hours the following day, and every 24 hours for at least 2 days. Several laboratory tests will reflect the cardiac stress of TCM. Commonly used markers are troponin T, creatine kinase, creatine kinase-muscle/brain, and myoglobin. Myoglobin is measured only at the beginning, as levels do not stay elevated longer than 8 hours. In most patients with TCM, there is a slight elevation in the cardiac enzyme levels on admission. These enzyme levels rapidly decline and do not seem to have prognostic prominence. Plasma B-type natriuretic peptide (BNP) levels, which can indicate ventricular dysfunction, are usually remarkably higher in TCM than in ST-elevation myocardial infarction (STEMI). Consequently, the ratio of BNP to peak troponin levels may help differentiate TCM from STEMI, as the larger numerator will create a higher ratio in TCM than is seen in STEMI (Fröhlich et al., 2012).

Echocardiography

The majority of patients with TCM show a loss of wall motion or hypokinesia at the apex on an echocardiogram (ECHO), as well as an apical balloon-like dilatation of the left ventricle on left ventricular angiography, whereas the base of the heart remains unaffected. Unlike an AMI, LV wall motion abnormalities are found beyond a single coronary artery perfusion area in patients with TCM (Fröhlich et al., 2012).

Left ventriculography

Ventriculography, during cardiac catheterization, will show the cardiac dysfunction associated with TCM. Specifically, it can identify the classic pattern of hypokinesis, akinesis, or dyskinesis of the apical and midventricular segments. Once again, the most telling diagnostic characteristic with TCM is the extension of myocardial abnormalities beyond a single epicardial coronary distribution (Scantlebury & Prasad, 2014).

Cardiac magnetic resonance imaging

Cardiac MRI is the ideal diagnostic method for TCM because it not only helps to identify the reversible myocardial damage by visualization of wall motion abnormalities and LVEF but also can confirm the absence of delayed gadolinium enhancement. Late gadolinium enhancement (LGE) assists cardiologists to determine tissue viability; with an AMI, the cardiac MRI will show LGE in the areas of necrosis, whereas TCM will not show LGE. Thus, TCM and an AMI can be differentiated (Scantlebury & Prasad, 2014).

Coronary angiography

In the acute phase, TCM patients manifest ST segment elevation on EKG and have presenting symptoms indicative of myocardial ischemia, which demand immediate assessment with coronary angiography to rule out coronary occlusion. As mentioned, TCM does not present with blocked coronary arteries or poorly perfused myocardial tissue. In fact, one of the most common characteristics of TCM is that complete recovery of cardiac function is achieved. The majority of patients with TCM show substantial improvement of systolic function within a week and attain complete recovery by the end of the third or fourth week after onset (Fröhlich et al., 2012).

Differential diagnosis

There are several life-threatening conditions that can have similar symptoms to TCM, so it is important to rule those diagnoses out.

  1. AMI: An AMI will cause elevated troponins, chest pain, and breathlessness but lacks the distinct ballooned heart shape of TCM. Additionally, TCM does not normally have the reciprocal EKG changes of an AMI. An MRI or coronary angiography is needed to determine patency of coronary vasculature (Kawai, Kitabatake, Tomoike, & Takotsubo CardiomyopathyStudy Group, 2007). Some have suggested using the ratio of BNP to troponin as an additional method of evaluating AMI versus TCM (Fröhlich et al., 2012).
  2. Pulmonary embolism (PE): A PE can cause chest pain and dyspnea. It can often be ruled out with a helical computed tomographic (CT) scan and a negative D-dimer (Kim, Yu, Filippone, Kolansky, & Raina, 2010).
  3. Severe brain injury: A brain injury can mimic TCM, as both show increased catecholamines, resulting in cardiac stunning and LV systolic dysfunction; a careful history, and physical and neurological assessment can guide the provider to a correct diagnosis (Akashi, Goldstein, Barbaro, & Ueyama, 2008, p. 2757).
  4. Pheochromocytoma: Pheochromocytoma can induce reversible cardiomyopathy related to elevated catecholamines and cardiac enzymes, and it may also show cardiac wall motion abnormalities. This condition can be ruled out with abdominal/pelvic imaging (Kim et al., 2010 Scantlebury & Prasad, 2014).

Diagnosis of takostubo cardiomyopathy based on Mayo Clinic criteria

There is no single diagnostic definition for TCM. The patient may present with signs and symptoms of acute coronary syndrome, pheochromocytoma, or myocarditis, and the provider is challenged to differentiate between these conditions. Based on expert opinion, the Mayo clinic criteria were developed from the atypical diagnostic pathway, and it is paraphrased below (Scantlebury & Prasad, 2014).

Mayo clinic criteria

  1. Regional LV wall motion abnormalities that may or may not include the apex; the hypokinesis, akinesis, or dyskinesis can be associated with a stressful trigger and should spontaneously resolve.
  2. No evidence of obstructed coronary arteries.
  3. Evidence, on electrocardiography or cardiac troponin, of cardiac stress as manifested by ST segment elevation or T wave inversion, or moderate elevation in cardiac troponin.
  4. No diagnosis of pheochromocytoma or myocarditis (Scantlebury & Prasad, 2014).

Therapeutic plan

There are no standard guidelines for the optimal management of patients with TCM. Initial presentation mimics an AMI in most of the TCM cases, and it is better to initiate myocardial ischemic management, such as administering supplemental oxygen, intravenous heparin, aspirin, and beta-blockers. Only after an AMI is excluded and TCM is confirmed, should this management be changed. Administration of beta-blockers is reasonable when there is no coronary spasm during the time of initial presentation. If coronary spasm is suspected, it is better to treat with calcium channel blockers. Angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor blocker can be used in reversible regional wall motion abnormalities. It is advisable to continue intravenous heparin after the confirmation of TCM to prevent LV apical thrombus formation. Medications for pain control, such as morphine, and nitrates for vasodilation, as well as inotropes to improve contractility, all play an important role in the management of TCM (Kurisu & Kihara, 2014). Further treatment in the case of complication, including the common development of heart failure, is discussed as part of the next section on prognosis.

Prognosis

Prognosis is generally favorable in the absence of comorbidity. The impaired LVEF related to the transient abnormal wall motion will resolve, EKG readings will normalize within days, and medical management is usually short term. However, in a few cases, life-threatening complications may occur. The majority of patients can expect a complete recovery within four to eight weeks, whereas 3% may have a recurrence. Shortly after TCM symptoms resolve, repeat EKG typically will show resolution of all electrophysiologic abnormalities, although T-wave inversion may persist. Mortality is approximately 1–2%. Clinicians may need to do more diagnostic tests if more contractile abnormalities are found (Kurisu & Kihara, 2014). Continuing care must include regular follow-up appointments after the patient is discharged home.

Complications

Heart failure is the primary complication of TCM, affecting 20% of the patients. Standard therapies, such as diuretics and nitroglycerin, are helpful in those with heart failure. Mitral regurgitation, related to the systolic anterior motion of the mitral valve leaflet and left mural thrombus, can lead to cardiogenic shock. In case of cardiogenic shock related to acute pump failure, intravenous fluids, inotropic agents, vasopressors, or intra-aortic balloon pump should be initiated. More severe complications, such as LV rupture or ventricular septal rupture, may occur from elevated LV wall stress and can be related to risk factors, such as older age or inadequate use of beta-blockers. Life-threatening arrhythmias, such as torsades de pointes (TdP) and ventricular fibrillation, may occur in 8.6% of TCM patients. Prolonged QTc interval may lead to TdP, which may be related to hypokalemia, hypomagnesemia, bradycardia, or certain anti-arrhythmia drugs, such as amiodarone (Kurisu & Kihara, 2014). Therefore, it is critical that these risk factors are recognized and corrected to decrease the risk of complications.

Case study

RG is a 71-year-old woman diagnosed with recurrent endocervical carcinoma who was admitted for fecaluria and fecal incontinence. A CT of abdomen and pelvis was performed and showed left pelvic sidewall abscess that communicated with the bladder. Bilateral nephrostomy tubes were placed. Resection of the peritoneal tumors was completed, and resection of the left descending colon with end colostomy was performed. Baseline EKG (Figure 2) is unremarkable. She had a history of hypertension, chronic kidney disease, gastroesophageal reflux disease, anxiety, depression, hydronephrosis, and hyperlipidemia. Her son was also recently diagnosed with sarcoma.
 

 

 

During ambulation, she started experiencing severe chest pain that radiated to the back and shoulder. A 12-lead EKG was completed and showed T-wave inversion, ST depression, and mild ST elevation, with the latter only present in leads II, III, and aVF (Figure 3). Cardiac enzymes were drawn and showed troponin trended from 0.54 to 2.26. An order for two-dimensional ECHO revealed LVEF of 65%. Cardiac catheterization was completed and revealed coronary arteries without occlusion or spasms. However, mild hypokinesis of the mid anterior and mid inferior walls of the left ventricle and mild residual midanterior and inferior hypokinesis was noted. These findings led to the diagnosis of TCM. She was then started on aspirin, clopidogrel, beta-blocker, and statins. Her pain was managed with oxycodone and resolved within a few days.

RG fits the typical TCM profile of a female, older than 66 years, who experienced several acute stressful events in a short period. Diagnosis of cancer is one of the most stressful events one can experience. In addition to this, RG underwent surgery due to acute illness, both of which are risk factors for TCM. Finally, sickness in a family member was another major stressor that compounded with her own physical stressors. All of these events significantly increased her risk for developing TCM.

 

Implications for practice

The nursing role in TCM has shown to improve health outcomes. The advanced practice nurse (APN) is instrumental in guiding the nurses in differentiating between TCM versus acute coronary syndrome, heart failure, pulmonary edema, dynamic outflow obstruction, and cardiogenic shock. Working closely with the staff nurses on the unit and continuously monitoring patients’ telemetry readings, specifically for third-degree atrioventricular blocks and ventricular arrhythmias are of the utmost importance. Left ventricular thrombus formation and free wall rupture has also been reported (Hanson, 2008). Because of these possible acute and critical presentations, prompt recognition and intervention for patients with TCM are priorities that APNs and nurses can help initiate. The APNs who recognize those patients who have risk factors for experiencing TCM should communicate these findings with the nurses, so that they can be aware of this possible complication. These patients should be placed on units with continuous cardiac monitoring, with nurses who have comprehensive knowledge of EKG interpretation, as EKG changes and arrhythmias are the early signs of worsening condition. Nurses should also have thorough knowledge of TCM presentations to anticipate patient treatment and patient education. Additionally, APNs need to recognize that postmenopausal women, including those without coronary artery disease-related risk factors, are considered a high-risk population for the development of TCM (Ferguson, 2015). The patient and family members should be involved in the education about the syndrome's reversibility, low rate of recurrence, and full recovery about the disease processes. It is especially important to emphasize the need for follow-up echocardiogram to track the resolution of the disease (Bascara, 2015). Anxiety, related to a new diagnosis of TCM, is to be expected from the patient and family members. It is here that a multidisciplinary approach can be very effective. If there were substantial stressors present prior to the onset of the signs and symptoms, the treatment team—particularly APNs, nurses, and social workers—needs to assess coping mechanisms and provide necessary psychological support. The specialty-specific knowledge from various team members can aid in patient development of healthy lifestyle changes and effective coping skills. Such changes can protect the patient from developing other more serious cardiac diseases (Middleton, 2017).

Conclusions

Takotsubo cardiomyopathy is diagnosed more frequently in postmenopausal women, who tend to be in their late 60s or older. It is portrayed by a transient hypokinesis of the LV apex and is often related to physical and/or emotional stress. The typical diagnostic workup includes EKG, cardiac biomarkers, and ECHO or coronary angiography. Treatment of TCM is usually supportive, as the apical wall motion abnormalities are usually transient and resolve within a few days to weeks. The outcome and prognosis of TCM is generally very good. However, there are some reports of serious TCM complications, including hypotension, heart failure, ventricular rupture, thrombosis involving the LV apex, and TdP. Health care providers should be aware of risk factors for developing TCM and provide education and counseling for those patients who exhibit signs and symptoms of acute coronary syndrome, especially if a stressful event occurred prior to the onset of signs and symptoms.

 

Theme 1: Low-dose computed tomography screening decision making—Competing demands. Nurse practitioners faced the complex task of balancing their knowledge of LDCT guidelines with the expectations and constraints of the NP role. Nurse practitioners described feeling “overwhelmed” by the need to consider competing demands within the context of providing excellent patient care (e.g., system demands related to patient turnaround time or regulations associated with the Affordable Care Act). In addition, as these NPs indicated that their patients never or very rarely requested screening of any type, they were completely responsible for initiating the conversation on the appropriateness of LDCT screening.

Low-dose computed tomography screening decision making. Most NPs were aware of current LDCT guidelines, as well as the efficacy of LDCT based on trial evidence, and used this knowledge to guide screening decision making. NPs indicated that they learned this information from professional journals and websites, colleagues, and their own literature searches. However, one NP questioned the legitimacy of the information received from a local facility that had a financial interest in obtaining patient referrals.

The major imaging center in our area would come and give us sort of bullet points on the major governing bodies and sort of help us to give them business. So, hopefully they were feeding me accurate information. They come into the offices. They bring lunches. They had pre-printed script pads for the LDCT scan. They had pamphlets that you could keep in your waiting rooms. I mean, they pushed pretty hard, obviously, to get our business.

Even so, the vast majority of interviewees could accurately relay screening guidelines and understood the increased efficacy of LDCT over previous treatment recommendations:

I know that they’ve done a lot of research. And that they used to recommend just a simple chest x-ray, and they found that chest x-rays can miss some things, and that’s why they recommend a CT of the chest—the lowdose one.

Interviewees could accurately relay the decreased risks of LDCT: “It [LDCT] has a better sensitivity with finding lung nodules with less radiation exposure. So, in that way, it’s safer and certainly more cost-effective.” The interviewed NPs could also relay location-specific knowledge: “Because of where we’re located geographically, we get a decent number of patients who are diagnosed with lung cancer, and it’s associated with 9/11, the World Trade Center.”

The complexity of the patients’ conditions affected whether some NPs decided to offer screening:

If they already have other compounding medical issues, at this point, why add one more? And I’ve had several train wrecks that could be like that too. So, you know, they already have kidney problems. Why try to find out if they have lung cancer too?

Other NPs firmly held that decision making should be a shared process between the provider and patient:

I think you have to take that shared approach with your patients to get anything done with them or for them. And if they’re not in agreement at the time that you see them, you can at least say, “Well, you can chew on that,” and then go from there. But, definitely shared.

 

 

The role of providers in low-dose computed tomography screening. Most NPs were adamant that recommendations for screening lay squarely within the primary care provider’s scope of practice and that they (the NPs) should take advantage of every engagement opportunity to suggest LDCT screening if the patient met the eligibility criteria for it: “I think the majority of the time, the primary care provider should be the one discussing these things with the patient, and then send them to the specialist.

Respectful working relationships with local pulmonologists or other specialists facilitated follow-up care if screening indicated the need for a referral:

We have a handful of pulmonologists that we use frequently, and we have a very good relationship, where I could call them on the phone and say, “Hey, I’m going to be sending this patient to you. This is their name. This is what I’m concerned about.” And they’ll be like, “Okay, great, thanks for the heads-up. We’ll look out for them.”

However, NPs often needed to creatively negotiate system constraints associated with ordering the screening, such as obtaining insurance approval:

Well, I don’t think I would have a problem doing it myself [ordering LDCT screening], but it definitely has a higher rate of approval if a specialist is ordering it, and then referring it to me to actually do the manual work.

The influence of others on decision making about screening. The NPs interviewed for this study generally evaluated their patients and made evidence-based recommendations. However, there were circumstances in which some NPs felt compelled to practice in ways contrary to established lung cancer screening guidelines. For example, although these NPs did not experience conflict with specialists such as pulmonologists, some experienced tension with clinic colleagues who opted for a different approach to lung cancer screening. One related how the power differential between her and her physician employer (who had a financial interest in CXR screening) influenced the screening process implemented at her practice site:

Well, it [LDCT] is supposed to be more efficient at screening for lung cancer than just routinely doing xrays, which [pause] the other physician in my office did a lot more chest x-rays on patients with a high smoking history who were over 50… [He] recommended that you offer them an x-ray, because it was incredibly cost-efficient and convenient at our site.

Consideration of patient desires and fears also affected NP decision making:

I think everybody has probably sent somebody for screening who really didn’t meet criteria, but they were just so anxious about it, and spent so much of their time thinking about this . . . that they’re just better off with, “Okay, let’s go get it done, if that’s what’ll, you know, help you sleep at night.

Theme 2: Guideline adherence—Identifying and responding to patient challenges. The NPs interviewed for this study consistently conveyed that the ability to provide excellent care was impossible without understanding the patient’s circumstances. However, this understanding often affected their ability or willingness to recommend LDCT screening.

I need to advocate for the patient. Is this the best time for this patient to undergo a cancer screening? What are this patient’s health care priorities?

Complex comorbidities. Screening for a potential problem seemed trivial when faced with the need to address existing, substantial concerns. Each NP related an experience with the multitude of patient issues that required attention during each appointment. One NP noted:

So you have to cover diabetes, hypertension, anemia, anything else, in that visit. Oh, and by the way, they probably have bronchitis or some other illness . . . . They have an infestation of bedbugs, or scabies, or something else that you have to talk to them about.

The NPs also expressed the need to consider the patient’s priorities:

It just seems like—at least, my population that I serve is very sick, underserved, underinsured, and usually the least of their concerns is that something may potentially be happening. They’re more worried about what is happening. Or what they perceive to be a problem, more so than what health-care providers perceive as a problem.

These NPs related that the reliance on acute, episodic care by the vast majority of their patients, coupled with patient resistance to preventive care, often resulted in unrealistic patient expectations:

I mean, we are a quick Band-Aid America these days. Everybody wants to continue to eat their junk food and smoke their cigarettes, and then they want to come to the hospital for a quick fix. They want me to fix it immediately. Honestly, I think that is the problem.

Nurse practitioner-related delays in appropriate care. Most of our patients are seeing us for the first time. They haven’t seen a provider in 10 years or longer, and they’ve never had any screenings done. Being referred to one more provider is going to take time . . . . So, when they already haven’t had healthcare for 10 years, making them wait months to see a specialist is just delaying their care longer.

Patient knowledge and attitudes. In addition to considering patients’ complex physical issues, NPs also had to take into account patients’ knowledge deficits related to a lack of public awareness. One NP said:

The American Heart Association has done a great job. Everybody wants to know their cholesterol level. You hear a lot about that and other screenings like Pap smears. But I don’t think that I’ve ever had one person ask about lung cancer screening.

Nurse practitioners also reported encountering patient fear and the psychological consequences of waiting for follow-up if LDCT screening revealed a suspicious nodule that did not warrant immediate intervention. A common occurrence encountered by these NPs was a sense of fatalism on the part of patients that was difficult to overcome:

The biggest barrier is that they’ve made their mind up. They’re set in their ways. You know, they’re going to die of something, so—why not lung cancer? I don’t know. They have that kind of mentality. So the patient actually being open to it—that’s the biggest barrier we hit.

Another common occurrence was outright denial or unwillingness to change behaviors:

A couple of them have said that they don’t want something [i.e., lung cancer screening] because, “Well I don’t plan on quitting smoking, so I don’t want to have any testing done.” And then I’ve had a couple [of patients] who say, “Well, if I found something, I wouldn’t want to know.”

Financial constraints. Practical issues such as economic pressures on patients are well documented and were a concern as well. A common experience among NPs when developing patient care plans was a perceived responsibility to consider how following LDCT recommendation guidelines may financially affect their patients:

I talk to them about lung cancer screening, and the hospital that we’re associated with charges, I think, like 99 bucks for a LDCT. But most of them can’t afford a $4 prescription, let alone $100 for a CT scan.

Even the costs associated with transportation were problematic for some patients:

For some of my patients who are on fixed or very little income, it’s hard for them to actually get to one of the hospitals that can do the screening. Gas money seems to be a barrier for them.

In many NP practice locations, insurance covered the initial screening CT. However, if a suspicious nodule was identified, any follow-up imaging was considered diagnostic rather than preventive and was not covered by insurance, thus making it cost prohibitive: “A lot of these low-cost insurances have very high deductibles, like $6,000 deductibles. And that’s really a lot of pressure for some families.”

The financial burden of follow-up affects patient decision making. One NP reported “Once they’ve been screened, they don’t want to go and do it again every year. They say, ‘Okay, I’m fine, there’s nothing wrong with me. Maybe in a few years I’ll check again.’” Financial concerns also affected provider decision making:

A lot of our patients have high deductibles and, you know, out-of-pocket expenses for patients are high. So, unless they’re sick, I oftentimes don’t talk people into doing things that cost a lot of money.

Responding to barriers. Nurse practitioners also had to consider the implications of screening barriers when assessing patients’ need for screening and facilitate negotiation of these challenges. One NP took a professional self-preservation approach when faced with patients unwilling to follow provider recommendations:

I do hear about some providers who dismiss a patient from their practice around issues like that. You know,“If you’re not going to follow the guidelines, then I don’t want a bad outcome on me.” That sort of mode of thinking. But we would not do that in our practice.

Nevertheless, in general, NPs reported using their knowledge of the contextual and individual patient factors to craft targeted interventions designed to facilitate better patient outcomes. For example, one NP anticipated potential patient barriers in the face of a positive screening result and incorporated solutions into patient care plans:

[I] bring them back into the office. I usually call them myself. I don’t let the secretaries or the medical assistants call. I just say,“We need to talk,” and,“Can you come in today?” I will already have an immediate appointment set up with a respiratory specialist. And then when they come in, I have the next appointment scheduled. “Well, you’re going to see Dr. Smith at four o’clock tomorrow.” I don’t want it to wait and that’s the way I handle it.

Other NPs included pragmatic solutions targeted to their particular location and patient population: “We implemented a service at our office, because of how poor our population is, where we actually pay for a taxi service so that they can travel to their appointments.”

Theme 3: Optimizing evidence-based practice—Provider facilitators and barriers. The NPs in this study identified specific tools and structural conditions that facilitated or hindered their ability to offer appropriate LDCT screening to their patients.

Financial incentives. For some NPs, the ability to bill for SDM visits was a financial incentive to complete the screenings:

Actually, our coder who comes around at least once monthly had mentioned that [ability to bill for SDM visits] to us before. I think we’re still trying to work on how to be more proficient in that, so that it doesn’t become too time-consuming compared to the amount of revenue [laughs] that you can bill for.

Optimal system management. When clinic systems (such as electronic medical record reminders) and personnel knowledge were congruent regarding LDCT screening, the NPs felt supported in their ability to provide appropriate screening recommendations to their patients, and patients were much less likely to be overlooked:

We use a check-off sheet with our patients, when they’re coming in for an annual exam. One of the questions prompts us to remember to ask them about screening… I think it’s like auto-populated in our electronic medical record. Because the guidelines are always changing, it’s hard to keep it straight… I think that the tool being built into our electronic medical record really helps…We have a very good administrative assistant in our office who handles all the referrals. She’s like the referral manager. And she does a really good job at getting insurance approval and this and that.

Provider inhibitors. When systems were not coordinated to facilitate individual practice, NPs indicated that they forgot to offer the screening or other concerns took precedence. Other inhibitors to optimal, evidence-based practice included individual provider knowledge deficits:

I’m really personally nervous about the radiation exposure. And I didn’t know that we can just jump to CT, or that we can start out screening with CT first. I thought it had to be chest x-ray first. Since that’s what most of my colleagues are doing, that’s what I tend to do too. So I haven’t really just jumped to CT.

Another inhibitor is ingrained group practice patterns: “And I think we are so ingrained in doing chest x-rays first . . . [laughs] because that’s been the longest practice. Do a chest x-ray. You know? So, this is relatively actually new, doing the LDCT scans.” Finally, in rural settings, provider turnover inhibited NPs’ ability to provide consistent care within their practice setting:

We have a lot of turnover with physicians and even nursing staff, currently. So until we can keep people long enough to start setting up some of that stuff, I don’t know if it’s ever going to happen. In rural communities, we get a lot of physicians who come here for short periods of time. You know, they sign a contract to work here to pay off their school loans for a couple, 3 years, and then they go home. It’s a rural area. People don’t dig it here.

Mapping quantitative and qualitative data

Mixing methods (i.e., collecting quantitative and qualitative data) facilitated a deeper interpretation of the survey responses. Both quantitative data generated by the survey and qualitative data generated from the telephone interviews were mapped against the conceptual framework of sequential change as proposed by Cabana et al. (1999). The framework (Figure 1) characterizes barriers as related to knowledge, attitudes, and behaviors. Our data show a high level of congruence between the conceptual framework and the quantitative and qualitative data.

Discussion

Clinical practice guidelines are systematically developed statements designed to guide health care providers and consumers in making decisions about the best care for specific clinical situations (Cabana et al., 1999). Successful guideline implementation accelerates the translation of research advances into clinical practice. However, the uptake of newly approved guidelines for cancer screening is a slow process that can be challenging and complex for practitioners in clinical or community-based settings (Kinsinger et al., 2017). Physician adherence to cancer screening guidelines is commonly studied. However, NP adherence is less studied and yet is critical to the translation of screening recommendations into improved outcomes (Haas et al., 2016). Nurse practitioners comprise the largest group of nonphysician primary care providers in the United States, and in rural areas they are becoming more central to the provision of primary care, especially for underserved, at-risk populations (Agency for Healthcare Research and Quality, 2012; Spetz, Skillman, & Andrilla, 2017).

In this national study, the response rate was lower than expected, despite using two response modalities. We implicate four factors with this response rate. First, the American Association for Public Opinion Research (AAPOR) acknowledges that response rates across all modes of survey administration have declined, in some cases precipitously (AAPOR, 2017). This drop is consistent with the response rate of mail surveys among groups of health professionals (Cho, Johnson, & Vangeest, 2013). Second, NPs in non–primary care adult settings may have been less likely to respond to the survey because it may have been outside their scope of practice. In addition, the response rate may reflect a lack of familiarity with lung cancer screening guidelines. Finally, the lack of financial incentive for survey completion may have played a role.

According to screening guideline adherence conceptual framework, knowledge, attitudes, and behaviors affect NPs’ ability to execute recommendations. Overall, this study revealed that knowledge and attitudes about lung cancer screening among a majority of NPs was suboptimal. Although the NPs were familiar with the existence of the USPSTF guideline, a minority of responders (35%) selected the correct screening strategy for a variety of patient scenarios. Clinical behaviors and practice patterns lagged behind their knowledge. Moreover, most NPs had not ordered an LDCT scan in the previous 12 months. Very few were familiar with the Medicare billing code used for SDM. The NPs spoke openly about their patients’ financial situations and competing health care demands. Although the initial screening would be free for many patients, additional scans and procedures together with the required deductibles would increase cost and inconvenience. The direct and indirect costs related to transportation and inevitable time off from work were sufficiently burdensome to lead patients and their providers to avoid the situation. Substantial external barriers that thwarted provider referrals included workload, lack of institutional administrative and electronic support systems–based solutions, availability of educational materials to facilitate brief SDM encounters, marketing materials to help identify high-risk patients and facilitate the referral process, and follow-up clinical resources for patient surveillance and treatment referrals.

Although most NPs described wanting to be involved in SDM regarding lung cancer screening, many reported not initiating conversations about the risks and benefits of LDCT screening. Barriers exist that prevent SDM engagement. Time is an influential factor related to SDM. When asked about the average number of patients seen per day, 24% of the NPs reported more than than 20 patients per day (Table 1). When the SDM process took more than 8 minutes as opposed to less than 3 minutes, the commitment to engaging in it decreased substantially (from 92% to 37%). Further documentation is needed on the role of the NP in recommending cancer screening and engaging in formal SDM for LDCT screening.

In addition to its mixed-methodology design, a strength of this study is that it is the first survey targeting NPs since the publication of the NLST results (NLST Research Team et al., 2011), the release of the screening recommendations from the USPSTF in 2013, and the CMS decision to provide coverage. As providers of care for most patients, all primary care providers play an essential role in the early detection of lung cancer.

Several limitations in our study should be noted. The response rate by this large sample of NPs was not optimal and limits the generalizability of our findings. A very high proportion of the sample (n = 305; 80%) agreed to the qualitative interview, which garnered them a $50 gift card in exchange for their participation—suggesting the importance of the “thank you” gift. Providing a gift for survey completion would likely have increased our analytic sample size. Of interest, approximately 69% of participants (n = 254) provide care to a primarily younger (<55-year-old) or mixed-age population of patients. This may have been a key factor in the lower survey response rate meaning that perhaps the survey was not relevant to their major focus of their practice with patients. Primary care providers are responsible for keeping abreast of a large volume of recommendations for screening services. It is understandable, therefore, that primary care providers prioritize the integration of frequently used guidelines for their patient populations. This lack of familiarity may affect survey participation and the actual responses.

Conclusions

This study illustrates the strengths of using a conceptual framework and a mixed-methods approach to study clinical guideline uptake among NPs in primary care settings. The explanatory sequential design allowed for a much deeper interpretation and expanded view of the barriers that emerged. This study helped foster greater understanding of the complexity of patient-related barriers, the difficulty in changing long-standing practice patterns, and the lack of systems-based solutions in primary care practice environments. Indeed, NPs seemed to welcome the opportunity to share with us the difficult aspects of their primary care practice as it relates to the translation and adoption of a cancer screening guideline. If this conclusion is correct, then the findings of this study have serious implications for the uptake of clinical guidelines for cancer screening.

In this study, the barriers far outweighed the facilitators. Approving and disseminating clinical practice guidelines and authorizing health insurance reimbursement are not enough. We agree with Haas et al. (2016) that it is imperative for guideline-issuing organizations to work with patient and provider stakeholder groups to ensure that stakeholder concerns are addressed. It cannot be overstated that lung cancer is the most common cancer and leading cause of death in men and women (Smith et al., 2017). We have the knowledge and technological capabilities to significantly reduce this burden, but we must be realistic that greater progress will not be made until a culture change occurs in which the early detection of cancer has greater value for policy makers, insurers, providers, and patients.


Acknowledgement: The authors would like to express their appreciation to Dana D. DeHart, PhD, Research Professor & Assistant Dean for Research, College of Social Work, University of South Carolina, Columbia, SC 29208, for reviewing this manuscript prior to submission.

Authors' contributions: Karen Kane McDonnell, Amy C. Dievendorf, Lauren Blew, Deborah Warden, Samira Khan, Erica Sercy, and Jan M. Eberth were involved in the design, implementation, and data management plan for the study, as well as in writing and reviewing this manuscript. Karen Kane McDonnell, Robin Dawson Estrada, and James W. Hardin conducted the quantitative and qualitative data analyses. All authors reviewed the final manuscript.

Funding: This work was supported by a University of South Carolina College of Nursing Preparatory Research Work Grant, an Office of Research Magellan Scholar Award, and an American Cancer Society Institutional Research Grant (124275-IRG-13-043-01-IRG).

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