Significance of Acute Coronary Syndromes
Coronary heart disease is responsible for more than 7 million deaths each year worldwide.1 However, since 1999, heart disease death rates have decreased by 25.8% in the United States, exceeding the American Heart Association's strategic goal of a 25% reduction by 2010.2 Despite these encouraging statistics, nearly 1.4 million Americans are projected to experience an episode of acute coronary syndromes (ACSs) in 2009.3
The Cost of Indecision: Myocardial Necrosis and Poorer Outcomes
Time to treatment for symptoms of ACSs can be a matter of life and death. Data suggest that up to half of patients with ACS experience sudden death prior to arrival in the emergency department (ED).3 In addition, degree of myocardial necrosis is related to length of the ischemic episode.4 As a result, there is a rapid diminishing benefit to reperfusion during myocardial infarction. Restoring flow to the affected artery within 30 minutes can abort an infarction. If reperfusion occurs within 2 to 3 hours, some preservation of myocardial function is achieved, but after 6 hours, there is little or no myocardial salvage.5 Numerous clinical trials have demonstrated that early presentation to the ED is associated with decreased mortality and decreased reinfarction rates for patients receiving thrombolytics.6,7 In addition, McNamara et al8 found that longer door to balloon time was associated with increased in-hospital mortality in a cohort study of 29,222 patient undergoing percutaneous coronary interventions.
Finally, those patients presenting for treatment in less than 2 hours remain the small minority making group comparisons across time a challenge. Prior research has shown that the median time to treatment varies from 1.1 to 24 hours.9-14 Studies show that as few as one-fifth of patients present to the hospital within 1 hour of symptom onset, whereas up to 40% delay more than 6 hours.15,16 In the Rapid Early Action for Coronary Treatment trial, the median time from symptom onset to arrival in the ED was 2.33 hours at baseline. Twenty-five percent of patients delayed longer than 5.2 hours. Delay time decreased by only 4.7% (7 minutes) per year over the 3 years of mass media messages targeting EMS utilization and reduced delay in presentation in the ED.17 This delay prevents the majority of patients from receiving optimal benefits of reperfusion therapy. Time to treatment for those with ST-segment elevation myocardial infarction (STEMI) is of particular concern because patients with complete occlusion benefit most from immediate reperfusion.
Factors Affecting Time to Treatment for ACSs
The most important factor impacting increased time to treatment for ACSs is the patient's decision to delay seeking care.18 It is essential to understand the decision-making processes that patients use that lead to delay in accessing emergency medical services or presentation to the ED, to decrease time to treatment. Rosenfeld10 and Rosenfeld et al19 examined decision-making patterns and their predictors in a sample of women with myocardial infarction. Most participants were categorized into 1 of 2 groups: those who knew they would seek assistance for symptoms (knowing) or those who decided to manage or minimize symptoms (managing). Those in the knowing group had a shorter median time to treatment compared with the managing group (0.90 vs 11.25 hours).10
Other studies have identified sociodemographic, cognitive/appraisal, behavioral, and illness factors impacting the time to treatment for symptoms of ACSs.20 Factors associated with increased time to treatment are older age, female sex, living alone, African American race,9,13,16,21-24 lack of recognition and discounting of symptoms,19,25,26 mismatch between expected and actual symptoms,27 maintaining a sense of normality,28 presence of third parties,19,27 self-treatment,29 stress and emotional states,30 and fear of bothering others.31 Factors associated with decreased time to treatment are higher perceived risk,31 fear of death,31 severity of symptoms,32 and access to emergency medical services.28 It is noteworthy that these data have been gathered in Asia, Europe, the Middle East, and the United States, suggesting that patient indecision and resulting delay in treatment are a global problem.
Identification of variables impacting the decision to seek care has the potential to reduce time to treatment and result in lower rates of sudden cardiac death, increased myocardial muscle preservation, and reduced mortality.33,34 Furthermore, results from studies sampling large heterogeneous populations will build on the knowledge garnered in small qualitative studies and may lead to effective interventions to hasten recognition of ACS symptoms, reduce time to presentation in the ED, and result in more expeditious treatment. Data for this analysis were part of a larger study examining sex differences in symptoms of ACSs.35 An exploratory aim of the study, reported here, was to identify factors associated with a decision to seek care in the ED for symptoms. The goals were to (1) describe word patterns patients use during ACSs, (2) explore reasons for seeking care in the ED, (3) identify categories of decision making, and (4) describe factors associated with time to presentation in the ED.
A descriptive, cross-sectional design was used to address the study aims. Factors impacting the decision to seek care in the ED were explored by asking 2 open-ended questions at the beginning of each interview. Patients were also asked when their symptoms began and what time they arrived at the ED. The medical record was searched in the few instances where the patient could not recall times. Time from symptom onset to arrival in the ED was then computed from patient report or medical records.
Sample and Setting
Two hundred eighty-two patients with an admitting diagnosis of ACSs were recruited from the cardiac step-down units at 2 urban, nonacademic, medical centers. Both are regional referral centers for local community hospitals with a combined total of more than 1,200 beds. One serves a large number of minority and indigent patients. Ten patients, 6 women and 4 men, declined to participate because of fatigue or lack of interest. One refused to sign the consent form. Six of the 10 patients were black, and ages ranged from 40 to 85 years. The remaining 272 patients gave written consent and completed the interview. Approval for the study was obtained from the institutional review boards at the sponsoring institution and both hospitals. Patients were eligible for the study if they were admitted through the ED at least 12 hours prior to interview with an admitting diagnosis of ACSs, at least 21 years old, fluent in English, and pain-free and had adequate cognitive capacity. Acute coronary syndromes were defined as unstable angina (UA), non-ST-segment elevation myocardial infarction (NSTEMI), or STEMI.36 Diagnosis was made according to the joint European Society of Cardiology/American College of Cardiology/American Heart Association guidelines. Unstable angina was diagnosed by clinical presentation. Non-ST-segment myocardial infarction was diagnosed by elevation in troponin I or T above referenced norms. ST-segment elevation myocardial infarction was diagnosed when ST segments were elevated by more than 1 mm in 2 contiguous leads or when pathological Q waves were present.37 Data from 16 patients whose admitting diagnosis of ACSs was not sustained and who were discharged with a primary diagnosis other than ACSs were excluded from analyses. This resulted in a final sample of 256. Possible symptom confounders were controlled for through design. Patients with documentation of prior heart failure, heart failure on admission, elevated brain natriuretic peptide, or cocaine use were excluded from the study.
Patients were interviewed in their hospital rooms after consent from each was obtained. All rooms on both step-down units are private, so confidentiality during interview was ensured. Two open-ended questions were asked prior to completion of quantitative tools: (1) What symptoms did you experience prior to coming to the ED for this hospitalization? and (2) What happened that made you decide to come to the hospital? These questions allowed the participants to focus on their personal experience during the episode of ACSs and to talk about their symptoms and decisions in their own words without introducing bias from items contained on the 20-item Symptoms of Acute Coronary Syndromes Index.35 In addition, patients were specifically asked to describe only symptoms associated with this acute event and not symptoms that could have been part of the prodrome. All data were collected by the principal investigator (PI) and 3 research nurses. One research nurse was a master's degree-prepared clinical instructor, and 2 were master's degree students. Interrater reliability was confirmed in 10% of interviews by the PI simultaneously completing the research tools while the research nurses conducted the interview. The mean correlation between raters on quantitative tools was 0.96.
Descriptive Content Analysis
All patient responses during interview were recorded verbatim and transcribed into a Word document. There were a total of 329 responses because many patients gave more than 1 reason for deciding to seek care in the ED. Data were analyzed by 4 members of the research team: the PI, a coinvestigator and qualitative methods expert, and 2 research assistants. The team met together to complete data analyses and discuss findings. Descriptive content analysis was used to establish categories in which responses from participants could be displayed.38 This method of analysis is the most straightforward type of qualitative analysis and allows for clear enumeration of data. Methods were used to enhance creditability and auditability39 including the following: data were analyzed by all team members simultaneously; categories were confirmed by all team members; disagreements were resolved through discussion until consensus was reached; and finally; further comparisons were made to identify commonalities and differences in the statements, which lead to refinement of the categories. We used an innovative statistical analysis in that the categories identified in the descriptive content analysis were used as predictor variables in a Cox proportional hazards model to examine time from symptom onset to arrival in the ED.
Patient characteristics and time from symptom onset to presentation in the ED were analyzed using SPSS (version 15; SPSS Inc, Chicago, Illinois). Dichotomous data were analyzed using the χ2 statistic, and continuous data were analyzed with independent-samples t tests. The 5 decision-making factors identified in the descriptive content analyses and other patient characteristics including age, marital status, income, education, history of heart disease, whether a healthcare provider was called, presence of a bystander, severity of symptoms, self-treatment of symptoms, and temporal nature of symptoms were treated as predictor variables in an analysis of time from symptom onset to arrival in the ED. Because of the nonnormality of the dependent variable (time from symptom onset to arrival in the ED), survival analysis was used to measure the effect of various baseline covariates on the time (measured in hours) from onset of symptoms to admission in the ED. Model selection consisted of initial univariate analysis using a log-rank test for categorical variables and a Cox proportional hazards model for continuous variables. Covariates with a P < .25 were selected for inclusion in a multivariate model, and stepwise selection was then used to attain a final Cox proportional hazards model. P < .25 was chosen because we wanted to err on the side of inclusion of potential covariates.40 There is no standard for how strong an association between a variable and the outcome of interest should be, although investigators often choose P <.25 based on prior empirical evidence.41 Katz40 cautions that in the presence of a suppressor effect, the variable may not even be weakly associated with the outcome in the bivariate analysis. We hypothesized this to be the case for the variables identified by patients in the qualitative analysis and for variables previously associated with time to presentation in the ED. The assumption of proportional hazards was tested including covariate * log(time) effects for all model covariates, with the test supporting the assumption of proportional hazards.
Clinical Characteristics of the Sample
A heterogeneous sample of nearly equal numbers of women (n = 112) and men (n = 144) was recruited. Convenience sampling was used, and eligible patients were recruited sequentially. No oversampling was done for women. The characteristics of women and men in the sample were similar except that women were significantly older and more likely to have a lower family income (Table 1). Both women and men were nearly equally divided into the 3 diagnostic categories of UA, NSTEMI, and STEMI. The only difference in symptom characteristics was that the men were more likely to state that symptoms were caused by exertion.
Word Patterns Used by Patients
The manner in which the patient articulated their symptoms sometimes varied significantly from the language of clinicians. For example, patients made a decision to go to the ED because "the chest pain was irritating," " I was feeling funny," "it hurt like hell," "I had convulsions," "I couldn't get out of the chair," "I got tired unloading pigs from a trailer," "I got extremely fatigued throughout the day," "the chest pain didn't even go away after vomiting," and "my throat tightened up when I was scraping a window." However, most patients used language similar to clinicians' language, particularly the words "chest pain" and "shortness of breath." Chest pain alone or in conjunction with other symptoms was noted in 36.5% of all responses.
Reasons for Seeking Care in the ED for Symptoms
When asked what made them decide to come to the ED, patients revealed specific symptoms, the severity or unremitting nature of the symptoms, and situational factors as reasons for seeking care when they did. Sixteen different symptoms were mentioned including typical symptoms such as chest pain, shortness of breath, and sweating and atypical symptoms such as convulsions, coughing, and upper back pain. Pain was most commonly described as discomfort, tightness, burning, pressure, and ache. Situational factors described related to time of day, location, or presence of a bystander. Nearly all of the 329 responses given by the patients fit into one of 5 categories, which were labeled new onset of chest pain, ongoing evaluation of symptom severity, symptoms other than chest pain that worsened or were unrelieved, externally motivated, and internally motivated. The categories and examples of responses given by patients from each category are found in Table 2.
Decision Making by Category
New onset of chest pain. As expected, patients reported chest pain more than any other symptom. The quality of the pain was described in a number of ways. Descriptors mentioned repeatedly were constant or unrelenting pain, unrelieved pain, pain that increased in intensity, or pain that awakened the patient from sleep. Some patients appeared to reach a tipping point where the severity of pain or unrelenting nature of the pain pushed them into a decision to seek care in the ED. Chest pain alone was mentioned 53 times by patients as the reason they decided to seek care in the ED when they did. It was reported in conjunction with other symptoms another 67 times. Patients also used other chest descriptors including discomfort, tightness, burning, pressure, and aching, another 20 times. Of note, patients seldom reported chest pain in isolation. Rather, they indicated that it was the primary symptom (or chief complaint) that caused them to come to the hospital.
Ongoing evaluation of symptom severity. Patients frequently monitored their symptoms but were often uncertain as to when to label their symptoms as serious or life-threatening and make the decision to go to the ED. One participant stated that they "knew something was happening, something that could be deadly." Over-the-counter medications, such as antacids, acetaminophen (Tylenol), aspirin, or ibuprofen, were used with carbonated beverages or Epsom salts (mixed in water and taken by mouth). When these strategies failed to provide relief, or provided only temporary relief, patients relabeled their condition as serious and decided to go to the ED. Several patients thought that their illness could be fatal and either called 911 or drove to the ED.
Symptoms other than chest pain that worsened or were unrelieved. Other symptoms that caused distress or concern and resulted in a decision to seek care were as follows, in order of most to least frequently reported: shortness of breath, sweating, arm pain, weakness, dizziness, indigestion, and vomiting. Also of note, the words fear, fright, scared, or afraid were frequently mentioned by participants. This sense of fear played a part in their reasoning and final decision to seek care. Symptoms other than chest pain that prompted a decision to go to the ED were mentioned 52 times, representing 15.8% of all reasons for making a decision to seek emergency treatment.
Externally motivated. In some instances, the patient allowed others to make the decision to go to the ED for them. Patients were most likely to seek the opinion of family members when they became ill. Of particular interest, female relatives including wives, daughters, and sisters were most often consulted and usually insisted that patients seek emergency care. Rarely did a participant state that he/she consulted with a male relative. One participant who did consult a male relative stated that his son was a paramedic and was adamant that he call 911.
Internally motivated. Many patients decided early and independently to consult others about the severity of their symptoms. Under these circumstances, they called healthcare professionals, most often physicians. Without exception, they were told to call 911 or go to the ED. In 1 case, a patient undergoing renal dialysis experienced symptoms, and the dialysis nurse called 911. Other patients described monitoring their symptoms and seeking advice if they considered the illness to be serious or they had not previously experienced similar symptoms. One participant reported that "the chest pain was unrelieved with movement, and when I started to sweat, I felt it was time to go to the hospital."
Time to Presentation in the ED
Time from symptom onset until presentation in the ED was available from 243 patients (95%) (Table 3). The majority of both women (61.6%) and men (53.5%) presented to the ED 6 hours or more after symptom onset. Although women delayed longer in seeking treatment, there was no significant difference in median time from symptom onset to arrival in the ED between women and men (9.5 vs 6 hours, log-rank test; P = .63). Even though a greater percentage of men arrived in the ED within 3 hours, they also exclusively delayed greater than 240 hours. Figure 1 shows time to treatment for women and men using a Kaplan-Meier survival curve.
Factors Associated With Time to Treatment
Cox proportional hazards model showed differences between groups for time to treatment in the ED. Patients exhibiting constant pain sought treatment earlier than those with single instance or intermittent pain (hazard ratio, 1.44; P = .01). Older patients sought treatment later than younger patients (hazard ratio, 0.99; P = .02). Even though the difference was statistically significant, the hazard ratio indicates that the difference may not be clinically significant. Finally, time to treatment for patients with STEMI was compared with that of patients with NSTEMI and UA to examine differences for patients with a complete occlusion requiring rapid reperfusion from those with an incomplete occlusion requiring medical interventions. Patients diagnosed with STEMI sought treatment earlier than those with UA (hazard ratio, 1.59; P = .004). The differences in time to presentation did not vary between patients with STEMI and NSTEMI (hazard ratio, 0.82; P = .21) (Table 4).
The most important findings in this study were that intermittent pain and older age were associated with increased time to treatment. No prior studies were found associating the temporal nature of ischemic pain with time to treatment. This is important information for clinicians because the pain of myocardial ischemia can come and go or can be temporarily relieved with vasodilators or analgesics. Therefore, nurses should caution patients at risk for an episode of ACSs that pain may be intermittent and that they may be tempted to wait to go to the hospital or try to treat their symptoms at home. This additional delay could result in irreversible myocardial damage. Other investigators have reported a link between older age and additional delay in time to treatment,42,43 and this information should also be conveyed to older patients at risk for ACSs.
Our findings had commonalities with Rosenfeld's10 study of decision-making patterns in women with myocardial infarction in that we identified patients who decided independently to seek care and who tried to manage symptoms prior to making a decision to go to the ED. However, neither factor influenced time to presentation in the ED. Severity of symptoms, one factor linked to reduced time to treatment in prior studies,21,44 was frequently reported as a reason for seeking care but did not predict time to treatment in the ED. Unlike participants in Noureddine's26 study, most of our patients recognized their symptoms as being serious or being of cardiac origin and eventually sought care in the ED. This is most likely attributable to sampling bias as admission to the hospital through the ED was a criterion for inclusion in the study. Even though all patients sought care in the ED, some consulted with a physician, family member, or acquaintance prior to arrival. Consultation has been associated with delayed treatment in previous studies31,45,46 but was not significant in this sample.
The most troubling finding was that only 20.3% of patients arrived in the ED in 2 hours or less. This is consistent with prior reports in the literature.15 Fifty-two percent of patients waited 6 or more hours to go to the ED, effectively closing the window of opportunity for reperfusion to rescue an ischemic myocardium. Importantly, women delayed 3.5 hours longer than men. Although the difference was not statistically significant, it is clinically significant as demonstrated in the reduction of myocardial preservation and increased mortality.5,7
An incidental finding was that patients with STEMI sought treatment sooner than did patients with NSTEMI or UA. Because the type of ACSs is not something that the patient could recognize, this finding requires further study. There may be some link between pathophysiological processes and appraisal of symptoms that impacts the decision to seek care more quickly for patients with STEMI.
Although the sample size, large number of women, and innovative analyses are strengths of the study, there were limitations. Convenience sampling was used so it is possible that the sample does not represent the total population of ACS patients. Participants responded to 2 open-ended questions for the qualitative component of this study. They were permitted to respond at length, but the investigators did not probe with follow-up questions to elicit more in-depth reasons for presenting to the ED. Access to care28 was presumed for this sample because all participants presented to the ED; however, we did not measure whether perceived access affected how quickly patients sought treatment. We also did not assess factors related to emergency medical services and insurance, which could factor into a decision to go to the ED.
Recommendations for Future Study
Findings from this study and from other research sampling large heterogeneous populations and using varied methodologies indicate that time from symptom onset to presentation in the ED remains dangerously long. In this study, only 30% of patients arrived in the ED at less than 3 hours from symptom onset. The consequences of this decision delay are often irreversible myocardial damage, long-term morbidity, or death. Identifying factors that affect patients' decision making may be the most useful strategy in developing interventions that are effective in changing patients' propensity for delayed care seeking. Community-based health messages and interventions have not been effective in decreasing decision delay. Future research should focus on designing empirically derived, tailored interventions delivered to patients at high risk for ACSs. Our findings suggest that special emphasis be given to women and older persons who are more likely to delay in seeking care and are at higher risk for poor outcomes. Interventions should include content on symptom perceptions and barriers and facilitators to behavior change.
The authors thank Dr Sally Rankin and Dr Mary Dawn Hennessey for their thoughtful critiques of the manuscript.
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Keywords:© 2010 Lippincott Williams & Wilkins, Inc.
acute coronary syndromes; decision making; emergency treatment