Risk of acute myocardial infarction in patients with non-typhoidal Salmonella infection: A nationwide matched population-based cohort study

Abstract

Objectives: We used a nationwide cohort to explore the association of non-typhoidal Salmonella (NTS) with risk of incident acute myocardial infarction (AMI).

Study design: Nationwide matched population-based cohort study.

Methods: We retrospectively analyzed a national insurance database, in which the NTS cohort (N = 15,152) and non-NTS cohort (N = 60,608) were individually-matched at 1:4 ratio by the index date, age, gender, and propensity score of comorbidities. Participants were identified by International Classification of Diseases, 9th Revision (ICD-9) codes from January 1, 2000 to December 31, 2014 and follow-up to Dec 31, 2017. Cox proportional hazard-models taking competing risk of death into account were adopted to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) of AMI. Multiple sensitivity analyses were conducted focusing on gender and comorbidities.

Results: The sub-distribution HR (sHR) of new-onset AMI was 1.63 (95 % CI, 1.32-2.01; p < 0.0001). Our findings were consistent across gender (female, sHR = 1.42; 0.98-2.07 and male, sHR = 1.72; 1.34-2.22). While a positive association between NTS infection and AMI risk was noted in individuals without comorbidities, the correlation persisted in those with diabetes (sHR = 1.85; 1.34-2.55), moderate to severe kidney disease (sHR = 3.02; 1.49-6.13), acquired immunodeficiency syndrome (sHR = 1.64; 1.33-2.02), gastroenteritis (sHR = 2.75; 1.32-5.74) and hypertension (sHR = 1.66; 1.28-2.15) CONCLUSIONS: The risk of AMI was significantly higher in the NTS cohort than that in the non-NTS cohort, indicating that NTS infection may be a potentially modifiable risk factor for AMI that warrants further studies for verification.

Keywords: Cohort; Epidemiology; Myocardial infarction; Non-typhoidal Salmonella.