Increased prevalence of infectious endocarditis in patients with type II diabetes mellitus.

BACKGROUND

Patients with diabetes mellitus (DM) are at increased risk of infection. However, there are controversial reports about DM association with infectious endocarditis (IE). We evaluated the occurrence of IE in DM patients compared to a matched control.

METHOD

Treatment files of inpatients' admission that contained discharge diagnosis (ICD-9 codes) from Veterans Health Administration hospitals were used for this study. ICD-9 codes for DM (n=293,124) and a control group with ICD-9 codes for hypertension without DM (n=552,623) were utilized for comparison. The prevalence of IE was studied using ICD-9 codes for IE. Multivariate analysis was performed adjusting for chronic and acute renal failure and aortic and mitral valve disease. Continuous variables were analyzed by unpaired t tests. Binary variables were analyzed using the chi-square test and Fisher's Exact Tests.

RESULTS

IE was present in 1340 (0.5%) DM patients versus 1412 (0.3%) patients from the control group (relative increase of 40%). Using multivariate analysis adjusting for renal failure and valvular abnormalities, DM remained independently associated with IE (odds ratio=1.9; 95% confidence interval=1.8-2.1; P<.0001).

CONCLUSION

Patients with type II DM have significantly higher prevalence of IE independent of renal failure or valvular abnormalities consistent with increased vulnerability of DM patients for infections.