IJCS | Volume 33, Nº1, January / February 2019

DOI: 10.5935/2359-4802.20190049 14 ORIGINAL ARTICLE International Journal of Cardiovascular Sciences. 2020;33(1):14-21 Mailing Address: Renato Lott Bezerra Rua Professor Morais, número 210, apartamento 303. Postal Code: 30150-370. Funcionários, Belo Horizonte, MG - Brazil. E-mail: lott.renato@gmail.com Association between Insulin use and Infective Endocarditis: An Observational Study Renato Lott Bezerra, 1, 4 T hales Figueiredo de Carvalho, 1 R icardo dos Santos Batista, 1 Yago Machado da Silva, 1 Bruno Fiuza Campos, 1 J oão Henrique Máximo de Castro, 1 M atheus de Carvalho Alves, 1 Pedro Ivo Palhares Monteiro, 1 Raimundo Matos Bezerra Filho, 2 E duardo Luis Guimarães Machado 1, 3 Faculdade de Ciências Médicas de Minas Gerais, 1 Minas Gerais, MG - Brazil Hospital Márcio Cunha, Fundação São Francisco Xavier, 2 Ipatinga, MG - Brazil Santa Casa de Misericórdia de Belo Horizonte, 3 Belo Horizonte, MG - Brazil Hospital João XXIII, Fundação Hospitalar do Estado de Minas Gerais, 4 Belo Horizonte, MG - Brazil Manuscript received on May 22, 2018, revised manuscript on September 11, 2018, accepted on November 01, 2018. Abstract Background: The association between Diabetes Mellitus (DM) and Infective Endocarditis (IE) is controversial in the literature, since many controversial results have been published. However, when evaluating specifically the evidence on IE and individuals with DM using insulin, we found only two observational studies that considered this variable, with discordant results regarding the prognosis and prevalence of Staphylococcus sp in insulin users compared to non-users. Despite the lack of evidence, in clinical practice the insulin use could be interpreted as minor criteria "injection drug use", using the modified Duke criteria for IE diagnosis. Objectives: To compare the microbiological and valvar profile, as well as the outcome of non-diabetic and diabetic patients with IE who were insulin users or not. Methods: This was an observational, analytical and retrospective study of patients diagnosed with IE between 2003 and 2015 in three tertiary care centers. A total of 211 patients were included, of which 17 were diabetics and 9 were insulin users. Patients were compared using the Shapiro-Wilk normality test and Fisher's exact test, with a significance level of 5%. Results: The mortality from IE in diabetic individuals was higher than that of non-diabetic patients, but with no statistical significance (35.29% vs. 21.1%; p = 0.221), even when the groups were divided into insulin-user diabetic, non-insulin user diabetic and non-diabetic patients (33.3% vs. 37.5% vs. 21.1%, p = 0.229). There was a difference regarding the prevalence of IE caused by S. aureus (57.1% vs. 14.3% vs. 17.4%, p = 0.029) and the involvement of the tricuspid valve (33.3% vs. 0.00% vs. 10.0%, p = 0.034) among insulin users. Conclusion: In our sample, insulin use or the presence of DM did not mean higher in-hospital mortality from IE. It is not possible to generalize the microbiological and valvar findings due to the lack of studies evaluating insulin users in IE; however, particularities have been previously reported and may indicate a different behavior of IE in these patients. New studies considering the insulin use variable are required to elucidate the association between DM and IE. (Int J Cardiovasc Sci. 2020;33(1):14-21) Keywords: Diabetes Mellitus; Insulin; Inyeccion; Infections; Heart Valve Diseases; Endocarditis, Bacterial. Introduction Infective Endocarditis (IE) is an infectious condition with high mortality that develops when bacteremia and endocardial tissue invasion occurs, usually in previously damaged cardiac valves. Several conditions have been associated with IE, such as congenital and rheumatic heart diseases, presence of prosthetic valves, prior IE and Diabetes Mellitus (DM). 1-4 DM is a high- prevalence disease, with an estimated 11.9 million affected individuals in Brazil and 387 million in the worldwide population. 5 It is a condition that leads to immunosuppression and, therefore, predisposes to several infectious complications. 6