Background: The main aims of this study were to describe trends and outcomes during admission for infective endocarditis (IE) in people ≥ 40 years old with or without type 2 diabetes distributed in five time-periods (2001-2003; 2004-2006; 2007-2009; 2010-2012 and 2013-2015), using Spanish national hospital discharge data.
Methods: We estimated admission rates by diabetes status. We analyzed comorbidity, therapeutic procedures, and outcomes. We built Poisson regression models to compare the adjusted time-trends in admission rates. Type 2 diabetes cases were matched with controls using propensity score matching (PSM). We tested in-hospital mortality (IHM) in logistic regression analyses.
Results: We identified 16,626 hospitalizations in patients aged ≥ 40 years for IE in Spain, 2001-2015. The incidence of IE increased significantly from 6.0/100,000 per year to 13.1/100,000 per year (p < 0.001) in the population with type 2 diabetes, and from 3.9/100,000 per year to 5.5/100,000 per year (p < 0.001) in the population without diabetes, over the study period. The adjusted incidence of IE was 2.2-times higher among patients with diabetes than among those without diabetes (IRR = 2.2; 95% CI 2.1-2.3). People with type 2 diabetes less often underwent heart valve surgery than people without diabetes (13.9% vs. 17.3%; p < 0.001). Although IHM decreased significantly in both groups over time, it represented 20.8% of IE cases among diabetes patients and 19.9% among PSM matched controls (p = 0.337). Type 2 diabetes was not associated with a higher IHM in people admitted to the hospital for IE (OR = 1.1; 95% CI 0.9-1.2).
Conclusion: Incidence rates of IE in Spain, among those with and without T2DM, have increased during the period 2001-2015 with significantly higher incidence rates in the T2DM population. In our population based study and after PSM we found that T2DM was not a predictor of IHM in IE.
Keywords: Comorbidities; Heart valve surgery; In-hospital mortality; Infective endocarditis; Type 2 diabetes mellitus.