Emotional Stress and Physical Exertion as Triggers of Acute Myocardial Infarction

Increasing evidence supports the role of acute triggers of acute myocardial infarction (AMI); however, the utility of their identification for preventive strategies has been limited.1Tofler GH Muller JE. Triggering of acute cardiovascular disease and potential preventive strategies.Circulation. 2006; 114: 1863-1872Crossref PubMed Scopus (219) Google Scholar It is also uncertain how patient perception of triggers may differ from triggers determined by case-crossover analysis. Perceptions and attitudes can impact patient behavior after AMI, including engagement in secondary prevention measures and cardiac rehabilitation. This study aimed to analyze patient perception of triggers of their AMI, with a focus on the 2 common triggers of emotional stress and physical exertion, and to characterize the potential modifiers of these triggers. The TAMAMI (Triggers and Modifiers of Acute Myocardial Infarction) study was a prospective, observational cohort study conducted at a tertiary referral hospital in Sydney, Australia between December 2005 and January 2017 with the Human Research and Ethics Committee approval. All patients who had coronary angiography after an acute coronary syndrome were screened for inclusion with the following criteria: (1) identifiable onset of chest pain or other typical symptoms, (2) elevated biomarkers of myocardial injury (troponin and/or creatinine kinase MB), (3) obstructive coronary artery disease on angiography, and (4) ability to complete a structured interview. Patients with confirmed obstructive coronary artery disease underwent a structured interview with a research nurse within 48 hours of admission. The interview included the question “Can you tell me briefly whether you think anything you experienced during the last few days contributed to your heart attack?” If they answered “Yes” or “Maybe,” they were asked to identify or name the possible trigger(s) in their own words. These answers were reviewed by an investigator and thematically categorized. Data were then analyzed using the IBM SPSS Statistics, version 26 (IBM Corp., Armonk, New York). Multivariate logistic regression analysis using backward elimination was performed to determine the independent predictors of identifying possible triggers. Covariates were selected based on a p <0.25 on univariate modeling. Of the 874 patients included, 405 (46.3%) identified a possible trigger, whereas 469 (53.7%) did not identify a trigger. Of those identifying a possible trigger, 204 (23.3%) answered “yes” and 201 (23.0%) answered “maybe” to whether they believed a trigger contributed to their AMI. Emotional stress (24.7%) and physical exertion (10.9%) were the 2 most reported triggers (Figure 1). Eighty-four patients (9.6%) identified more than one possible trigger. Baseline characteristics and univariate predictors of patient perception of any trigger, emotional stress, or physical exertion are presented in Table 1. Multivariate logistic regression modeling confirmed that previous chest pain was associated with a higher likelihood of identifying any trigger (odds ratio OR 1.40, 95% confidence interval CI 1.06 to 1.85, p = 0.018) and older age with a lower likelihood of identifying any trigger (OR 0.983, 95% CI 0.97 to 0.99, p = 0.002). Patients who identified emotional stress as a trigger were younger (OR 0.98, 95% CI 0.97 to 0.99, p = 0.005), more likely to be female (OR 1.80, 95% CI 1.18 to 2.75, p = 0.007), and more likely to have had previous chest pain (OR 1.63, 95% CI 1.17 to 2.27, p = 0.004). Although patients taking β blockers were less likely to identify emotional stress as a trigger on univariate analysis (OR 0.53, 95% CI 0.29 to 0.96, p = 0.032), this association was not statistically significant in multivariate analysis (Table 1). Patients who identified physical exertion as a trigger were more likely male (OR 3.03, 95% CI 1.30 to 7.07, p = 0.011) and less likely active smokers (OR 0.503, 95% CI 0.267 to 0.945, p = 0.033) in multivariate analysis.Table 1Characteristics of patients who identified any trigger, specifically emotional stress or physical exertionAllAny TriggerEmotional StressPhysical ExertionYesNop-valueYesNop-valueYesNop-valueAll Patients (%)874 (100)405 (46.3)469 (53.7)-216 (24.7)658 (75.3)-95 (10.9)779 (89.1)-Age Mean ± SD59.8 ± 12.858.4 ± 12.561.6 ± 12.90.003*p-value <0.05.58 ± 12.060 ± 13.00.015*p-value <0.05.61 ± 12.860 ± 12.80.351Male Sex (%)729 (84.1)337 (84.0)392 (84.1)0.974169 (79.3)560 (85.6)0.029*p-value <0.05.88 (93.6)641 (82.9)0.007*p-value <0.05.EthnicityCaucasian (%)776 (90.4)367 (91.5)409 (89.5)0.379192 (90.1)584 (90.5)0.93991 (96.8)685 (89.7)0.202Asian (%)60 (7.0)22 (5.5)38 (8.3)16 (7.5)44 (6.8)2 (2.1)58 (7.6)Indigenous (%)11 (1.3)6 (1.5)5 (1.1)2 (0.9)9 (1.4)0 (0)11 (1.4)Other (%)11 (1.3)6 (1.5)5 (1.1)3 (1.4)8 (1.2)1 (1.1)10 (1.3)Maximum Schooling LevelPrimary (%)34 (3.9)12 (3.0)22 (4.8)0.1695 (2.4)29 (4.5)0.1165 (5.3)29 (3.8)0.202Secondary (%)530 (61.6)238 (59.8)292 (63.1)122 (58.1)408 (62.7)50 (53.2)480 (62.6)Tertiary (%)297 (34.5)148 (37.2)149 (32.2)83 (39.5)214 (32.9)39 (41.5)258 (33.6)Hypertension (%)405 (46.6)177 (43.9)228 (48.8)0.14893 (43.1)312 (47.7)0.23544 (46.3)361 (46.6)0.961Hypercholesterolemia (%)415 (47.7)190 (47.1)225 (48.2)0.761101 (46.8)314 (48.0)0.74938 (40.0)377 (48.6)0.111Diabetes Mellitus (%)138 (15.9)61 (15.1)77 (16.5)0.58632 (14.8)106 (16.2)0.62713 (13.7)125 (16.1)0.538Current Smoker (%)187 (21.4)86 (21.2)101 (21.5)0.91452 (24.1)135 (20.5)0.26912 (12.6)175 (22.5)0.027*p-value <0.05.Family History of IHD (%)355 (40.8)171 (42.4)184 (39.4)0.36487 (40.3)268 (41.0)0.85643 (45.3)312 (40.3)0.349Previous History of IHD (%)154 (17.7)70 (17.4)84 (18.0)0.81233 (15.3)121 (18.5)0.28217 (17.9)137 (17.7)0.958Previous AMI (%)123 (14.1)55 (13.6)68 (14.6)0.70026 (12.0)97 (14.8)0.30713 (13.7)110 (14.2)0.893Previous CABG (%)53 (6.1)18 (4.5)35 (7.5)0.0638 (3.7)45 (6.9)0.0914 (4.2)49 (6.3)0.417Previous PCI (%)85 (9.8)42 (10.4)43 (9.2)0.54818 (8.3)67 (10.2)0.4129 (9.5)76 (9.8)0.918Beta Blocker (%)90 (10.3)35 (8.7)55 (11.8)0.13214 (6.5)76 (11.6)0.032*p-value <0.05.6 (6.3)84 (10.8)0.173Aspirin (%)130 (14.9)58 (14.4)72 (15.4)0.66125 (11.6)105 (16.0)0.11116 (16.8)114 (14.7)0.579Statin (%)164 (18.8)72 (17.8)92 (19.7)0.47932 (14.8)132 (20.2)0.08215 (15.8)149 (19.2)0.422ACEI/ARB (%)233 (26.8)101 (25.0)132 (28.3)0.27854 (25.0)179 (27.3)0.50321 (22.1)212 (27.3)0.278Previous chest pains (%)358 (43.1)183 (47.2)175 (39.5)0.026*p-value <0.05.103 (51.0)255 (40.5)0.009*p-value <0.05.50 (54.3)423 (57.2)0.597Previous diagnosis of angina (%)119 (14.1)61 (15.4)58 (12.9)0.31330 (14.3)89 (14.0)0.92213 (13.8)106 (14.1)0.940Single vessel disease (%)429 (49.3)195 (48.8)234 (50.3)0.645111 (52.1)318 (48.8)0.39743 (45.7)386 (50.1)0.429Pre-PCI TIMI 2 or 3 (%)377 (44.4)175 (44.8)202 (44.1)0.84992 (43.8)285 (44.6)0.84136 (39.1)341 (45.0)0.281Post-PCI TIMI 2 or 3 (%)744 (98.8)345 (98.3)399 (99.3)0.225186 (98.9)558 (98.8)0.84886 (98.9)658 (98.8)0.967AMI occurring on Weekend (%)243 (27.8)113 (27.9)130 (27.7)0.95262 (28.7)181 (27.5)0.73428 (29.5)215 (27.6)0.700 p-value <0.05. Open table in a new tab The finding that almost half of patients (46.3%) identified a possible trigger is consistent with previous studies, including 48.5% in the Multicenter Investigation of Limitation of Infarct Size (MILIS) study2Tofler GH Stone PH Maclure M Edelman E Davis VG Robertson T Antman EM Muller JE. Analysis of possible triggers of acute myocardial infarction (the MILIS study).Am J Cardiol. 1990; 66: 22-27Abstract Full Text PDF PubMed Scopus (314) Google Scholar and 47% in a study by Sumiyoshi et al.3Sumiyoshi T Haze K Saito M Fukami K Goto Y Hiramori K. Evaluation of clinical factors involved in onset of myocardial infarction.Jpn Circ J. 1986; 50: 164-173Crossref PubMed Scopus (42) Google Scholar MILIS also reported that younger patients were more likely to identify a trigger.2Tofler GH Stone PH Maclure M Edelman E Davis VG Robertson T Antman EM Muller JE. Analysis of possible triggers of acute myocardial infarction (the MILIS study).Am J Cardiol. 1990; 66: 22-27Abstract Full Text PDF PubMed Scopus (314) Google Scholar We found no significant association between trigger identification and cardiovascular risk factors, in contrast to studies finding that patients with hypertension,4Brodov Y Sandach A Boyko V Matetzky S Guetta V Mandelzweig L Behar S. Acute myocardial infarction preceded by potential triggering activities: angiographic and clinical characteristics.Int J Cardiol. 2008; 130: 180-184Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar diabetes,2Tofler GH Stone PH Maclure M Edelman E Davis VG Robertson T Antman EM Muller JE. Analysis of possible triggers of acute myocardial infarction (the MILIS study).Am J Cardiol. 1990; 66: 22-27Abstract Full Text PDF PubMed Scopus (314) Google Scholar renal impairment,4Brodov Y Sandach A Boyko V Matetzky S Guetta V Mandelzweig L Behar S. Acute myocardial infarction preceded by potential triggering activities: angiographic and clinical characteristics.Int J Cardiol. 2008; 130: 180-184Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar or previous angina3Sumiyoshi T Haze K Saito M Fukami K Goto Y Hiramori K. Evaluation of clinical factors involved in onset of myocardial infarction.Jpn Circ J. 1986; 50: 164-173Crossref PubMed Scopus (42) Google Scholar were less likely to identify triggers. Gender and age have been previously reported to modify the association between emotional stress and cardiac events. Vaccarino et al5Vaccarino V Wilmot K Al Mheid I Ramadan R Pimple P Shah AJ Garcia EV Nye J Ward L Hammadah M Kutner M Long Q Bremner JD Esteves F Raggi P Quyyumi AA Sex differences in mental stress-induced myocardial ischemia in patients with coronary heart disease.J Am Heart Assoc. 2016; 5e003630Crossref Scopus (77) Google Scholar found that younger women, especially those ≤50 years, were 3 times more susceptible to stress-induced myocardial ischemia measured by perfusion imaging. Strike et al6Strike PC Perkins-Porras L Whitehead DL McEwan J Steptoe A. Triggering of acute coronary syndromes by physical exertion and anger: clinical and sociodemographic characteristics.Heart. 2006; 92: 1035-1040Crossref PubMed Scopus (104) Google Scholar reported that anger preceding AMI was associated with younger age and lower socioeconomic status. In our study, patients taking β blockers before their AMI were less likely to perceive emotional stress as a trigger in univariate but not multivariate analysis. Bhattacharyya et al7Bhattacharyya MR Perkins-Porras L Wikman A Steptoe A. The long-term effects of acute triggers of acute coronary syndromes on adaptation and quality of life.Int J Cardiol. 2010; 138: 246-252Abstract Full Text Full Text PDF PubMed Scopus (11) Google Scholar reported that patients on β blocker therapy before their AMI had lower levels of anxiety at 12 months after AMI, suggesting that modifiers of acute triggers may have longer-term impacts. We found that previous chest pain was associated with perceiving emotional stress but not physical exertion as a trigger, suggesting that these patients were possibly avoiding physical exertion to prevent further chest pain but had more difficulty avoiding emotional stress. Further study into how a history of previous chest pain affects patients’ perception of triggers may reveal further strategies to ensure early symptom recognition and presentation. In the Onset study, patients who had experienced anxiety in the 2 hours preceding their AMI had a 44% higher 10-year all-cause mortality rate.8Smeijers L Mostofsky E Tofler GH Muller JE Kop WJ Mittleman MA. Association between high levels of physical exertion, anger, and anxiety immediately before myocardial infarction with mortality during 10-year follow-up.J Am Coll Cardiol. 2015; 66: 1083-1084Crossref PubMed Scopus (6) Google Scholar The increased rate was particularly seen among women. AMI triggered by emotional stress has also been associated with elevated anxiety levels at 12 and 36 months after AMI and increased 30-day rehospitalization.7Bhattacharyya MR Perkins-Porras L Wikman A Steptoe A. The long-term effects of acute triggers of acute coronary syndromes on adaptation and quality of life.Int J Cardiol. 2010; 138: 246-252Abstract Full Text Full Text PDF PubMed Scopus (11) Google Scholar,9Tofler GH Kopel E Klempfner R Eldar M Buckley T Goldenberg I National Israel Survey of Acute Coronary Syndrome Investigators. Triggers and timing of acute coronary syndromes.Am J Cardiol. 2017; 119: 1560-1565Abstract Full Text Full Text PDF PubMed Scopus (13) Google Scholar AMI triggered by physical exertion has been associated with poorer long-term physical health (measured by the SF36 scale) at 12 and 36 months but reduced in-hospital and 30-day mortality compared with AMI not triggered by physical exertion.7Bhattacharyya MR Perkins-Porras L Wikman A Steptoe A. The long-term effects of acute triggers of acute coronary syndromes on adaptation and quality of life.Int J Cardiol. 2010; 138: 246-252Abstract Full Text Full Text PDF PubMed Scopus (11) Google Scholar,9Tofler GH Kopel E Klempfner R Eldar M Buckley T Goldenberg I National Israel Survey of Acute Coronary Syndrome Investigators. Triggers and timing of acute coronary syndromes.Am J Cardiol. 2017; 119: 1560-1565Abstract Full Text Full Text PDF PubMed Scopus (13) Google Scholar An AMI is perceived by many patients to be an unexpected and a significant negative life event. A “search for meaning” after such an event is an adaptive cognitive process that is unique to each patient and includes attributing the event to a trigger.10Skaggs BG Barron CR. Searching for meaning in negative events: concept analysis.J Adv Nurs. 2006; 53: 559-570Crossref PubMed Scopus (77) Google Scholar The high percentage of triggers perceived by patients and the presence of significant modifiers suggest that further research into triggering of AMI and its potential longer-term impacts is warranted. A better understanding of how patients perceive triggers may provide insights into developing more engaging and empowering secondary prevention strategies. The authors have no competing interests to declare.