There is an established association between fast-food consumption and metabolic diseases. Some studies also suggest that calorie-dense food promotes a proinflammatory response, which is itself linked with myocardial infarction (MI). Whether increased fast-food availability is a risk factor for MI remains unknown.
To investigate the role of fast-food outlet density as a novel environmental risk factor for myocardial infarction in the Hunter region, NSW.
We conducted a retrospective cohort study using a database of all MI events between 1996-2013, extracted from the Hunter Cardiac and Stroke Outcomes unit. Fast-food outlet density (FFD) was calculated for each local government area (LGA) of the Hunter region, allowing for a comparative analysis. Stratification by fast-food outlet data and LGA resulted in a total of 3070 cases. Weighted linear regression was used to investigate the role of fast food outlet density on incidence of myocardial infarction in regional and rural Australia.
FFD was positively correlated with rates of MI, remaining consistent in both single and multivariate predictor models adjusting for age, obesity, hyperlipidaemia, hypertension, smoking status, diabetes and socioeconomic status (p < 0.001). An increase of one fast-food outlet corresponded with four additional cases of MI per 100 000 people per year (4.07, 95% CI. 3.86-4.28).
Fast-food outlet density was positively associated with incidence of myocardial infarction in both rural and metropolitan areas of NSW. This relationship remained consistent after multivariate adjustment for standard cardiovascular risk factors, highlighting the importance of an individual’s food environment as a potential contributor towards their health.