Theory-based cognitive–narrative intervention versus didactic education for promoting prompt care-seeking for acute myocardial infarction: A multisite mixed-methods randomized controlled trial

Prolonged delays by patients in making care-seeking decisions remain a significant obstacle to the effective management of acute myocardial infarction. This study aimed to compare the effects of a theory-based cognitive–narrative intervention with those of didactic education over a 24-month period on the participants' attitudes, beliefs, and knowledge regarding acute myocardial infarction, prehospital delay time, and the use of an ambulance. We also explored participants' engagement in the intervention. This study adopted a sequential mixed-methods design comprising a multisite randomized controlled trial and a qualitative study. Community-dwelling adult patients with a prior history of acute myocardial infarction in the past year were recruited from four hospitals in Hong Kong. They were randomly assigned to an 8-week theory-based cognitive–narrative intervention that involved a vivid experience of complex decision-making or didactic education. The Acute Coronary Syndrome Response Index questionnaire was administered at baseline (T0) and at 3- (T1), 12- (T2), and 24-month (T3) follow-up time points. Prehospital delay time and the use of an ambulance were evaluated for those participants who had recurrent acute myocardial infarction attacks during the study period. A total of 608 participants were randomly assigned to the theory-based cognitive–narrative intervention group (n = 304) or the didactic education group (n = 304). The intervention group reported greater improvements than the control group in their attitudes (β = − 1.053, p = 0.002) and beliefs (β = − 0.686, p = 0.041) regarding acute myocardial infarction and care-seeking at T1. These effects were sustained at T2 [attitudes (β = − 0.797, p = 0.018); beliefs (β = − 0.692, p = 0.047)] and T3 [attitudes (β = − 0.717, p = 0.024); beliefs (β = − 0.701, p = 0.032)]. Sixty-three participants experienced another acute myocardial infarction event by T2. The median delay times for the intervention and control groups were 3.13 h (interquartile range (IQR: 1.15–6.48)) and 4.82 h (IQR: 2.23–9.02), respectively. The prehospital delay time was significantly reduced in the intervention group compared with the control group (β = − 0.07, p = 0.011). The qualitative findings echoed the quantitative findings, as participants indicated that the intervention helped them to understand the variable nature of the disease presentation, which enabled them to recognize the symptoms more readily. The novel cognitive–narrative intervention used in this study effectively improved the participants' attitudes and beliefs regarding acute myocardial infarction and reduced the prehospital delay time. This study was registered with the International Clinical Trials Registry Platform of the World Health Organization (ChiCTR-IIC-17010576) on February 2, 2017; the first participant was recruited on January 11, 2018.