In-depth look into urban and rural disparities in prehospital delay in patients with acute ST-elevation myocardial infarction and its impact on prognosis: a prospective observational study

Abstract

Objectives: In line with the cardiac fast track, the 'green pathway for patients with heart attack' policy in China is implemented to reduce door-to-balloon time in patients with ST-segment elevation myocardial infarction (STEMI). However, the difference in prehospital delay between urban and rural areas of China and its impact on prognosis is unclear.

Design: Prospective observational study.

Setting: This study was conducted in a tertiary hospital, the only nationally accredited chest pain centre with percutaneous coronary intervention (PCI) capacity in Pizhou, China.

Participants: 394 patients with STEMI without patients with in-hospital STEMI or patients lost to follow-up were included.

Primary outcome measures: Primary outcome was major adverse cardiovascular events (MACEs), including cardiac death, non-fatal myocardial infarction and heart failure.

Results: Among 394 patients enrolled, 261 (66.2%) were men, the median age was 69 years (interquartile range: 61-77 years), and 269 (68.3%) were from rural areas. Symptom-to-door (S2D) time was significantly longer for rural patients than for urban patients (p<0.001). Cox regression analyses revealed living in rural areas was independently associated with prolonged S2D time (adjusted HR 0.59; 95% CI 0.43 to 0.81; p=0.001). HR of <1 indicates that the S2D time is longer for patients in the rural group (group of interest). During 1-year follow-up, the incidence of MACEs was higher in rural patients (p=0.008). The unadjusted OR for MACEs between rural and urban patients was 2.22 (95% CI 1.22 to 4.01). Adjusting for sex did not attenuate the association (OR 2.06; 95% CI 1.13 to 3.76), but after further adjusting for age, cardiac function classification, S2D time and performance of primary PCI, we found that odds were similar for rural and urban patients (OR 1.19; 95% CI 0.59 to 2.38).

Conclusions: Rural patients with STEMI had a longer S2D time, which led to a higher incidence of MACEs. This study provides rationales for taking all the measures to avoid prehospital delay.

Keywords: Coronary heart disease; Coronary intervention; Myocardial infarction.