Abstract Background Diabetes mellitus (DM) is prevalent in up to 30% of patients with infective endocarditis (IE) and this is associated with more severe outcomes. Current guidelines have no specific recommendations for patients with IE and DM, yet they constitute an important and vulnerable subgroup of patients. Purpose The aim of this cohort study was to report clinical characteristics, microbial etiology, and in-hospital mortality for patients with IE by DM status. Methods We used the National Danish Endocarditis Studies (NIDUS) registry. NIDUS is an all-comer Danish nationwide cohort of patients with IE between 2016-2021 with comprehensive clinical data. We included patients with left-sided IE who did not have missing information regarding DM status and had no prior IE. We grouped patients by DM status, and reported who were insulin dependent. We compared their characteristics and in-hospital mortality. Results We included 2,878 patients with left-sided IE. There were 662 (23.0%) with IE and DM (insulin dependent: 46.7%). A definite diagnosis of IE was recorded similarly between the groups (82.5% vs. 80.5%), the rest had possible IE. Male sex and median age (25th-75th percentile) for patients with IE and DM was 65.6% and 73.1 years (66.2-79.1), and this was 66.8% and 74.4 years (64.7-81.4) in those without DM. Patients with IE and DM presented more often with kidney disease and dialysis (32.2% and 10.1%), compared to those without DM (12.0% and 3.8%). The most predominant microorganism was S. aureus (34.1%) among patients with IE and DM, but this was Streptococcus spp. (33.9%) among patients without DM, see Figure 1. Suspected point-of-entry was available for 66.5% of the patients, and skin was reported more often for patients with IE and DM (19.8% vs. 15.8%, P=0.03). Healthcare acquired IE was reported similarly between the groups (24.5%, vs. 21.5%, P=0.124). The diagnostic echocardiography showed reduced ejection fraction (≤45%) more often for patients with IE and DM compared to those without DM (14.7% vs. 10.5%), and similar proportions of large vegetations ≥10 mm (39.4% vs. 41.4%). IE related to prior prosthetic heart valve (PVE) was also reported with similar rates in both groups (23.0% vs. 23.3%), but patients with IE and DM underwent valve surgery less frequently (17.2% vs. 23.3%). Absolute in-hospital mortality was higher for patients with IE and DM compared to those without DM (23.0% vs. 16.3%, P0.01). Adjusted in-hospital mortality was higher for patients with IE and DM compared to those without DM (HR=1.28 95% CI: 1.05-1.56). Conclusions Patients with IE and DM presented with higher proportions of key comorbidities, had a higher proportion of S. aureus, point-of-entry was more often related to skin, and absolute and adjusted in-hospital mortality was higher compared to those without DM. Our findings highlight the need for further research into this clinically important patient group who experience more severe outcomes.
Jensen et al. (Sat,) studied this question.