Controlling Nutritional Status (CONUT) Score: a new tool for characterization and prognosis of patients with infective endocarditis

Abstract Background malnutrition is a marker of unfavorable prognosis in different medical conditions, however, the association between new objective immunonutritional indexes and outcomes for patients with infective endocarditis (IE) is not fully studied. Purpose the aim of this study was to assess the role of the Controlling Nutritional Status (CONUT) Score in the characterization of patients with IE and its association with prognostic outcomes. Methods a total of 184 cases of confirmed IE were consecutively collected and followed during one year after diagnosis in two tertiary hospitals. CONUT score was calculated using serum albumin, total cholesterol and lymphocyte count [(range 0-12), the higher, the worse] at diagnosis, and patients were categorised as CONUT-high (>=6, n=98), and CONUT-low (<6, n=86) based on the sample median value. Results mean age was 70 [SD 15] years, 64% were men and community-acquired infections were 69%. Median score value was 6 (4). As shown in Table 1 and 2, diabetes and frailty were more prevalent in CONUT-high group, who showed a worse profile of nutritional biomarkers. Overall, the most frequent pathogen was S. viridans (n=43). By groups, S. aureus was predominantly isolated in CONUT-high (20 vs 8%; p 0.02), and non-viridans streptococci in CONUT-low (9 vs 2%, p 0.03). Regarding infection site, IE of aortic bioprostheses was more common in CONUT-high, whereas mechanical aortic valves and mitral bioprostheses were more frequently involved in CONUT-low. Larger vegetations [14 (11) vs 11 (7) mm, p 0.02], and more periannular abscesses (25 vs 13%, p 0.04) were detected in CONUT-high, who presented more acute kidney injury and septic shock during hospitalization. Despite higher predicted surgical risk in CONUT-high, neither the proportion of patients who underwent surgery nor in-hospital mortality, differed between groups. When analyzing according to the therapeutic approach, only among those medically managed patients without surgical indication, in-hospital mortality was higher in CONUT-high. At 1-year follow-up, rehospitalization rate tended to be lower in those with a better nutritional status (35% vs 51%, p 0.07). Conclusions in patients with IE and a high CONUT score, diabetes and frailty were more prevalent. In addition, virulent pathogens, larger vegetations and periannular complications were more frequently reported. Although surgery performance and in-hospital mortality did not differ between groups, a worse nutritional status was associated with a higher rate of clinical complications and higher mortality among patients with conservative management who did not meet surgical criteria.