To our knowledge, this is the first report that evaluates the impact of obesity on outcomes associated with Candida bloodstream infections. Similar to reported trends in Candida epidemiology, the predominantly identified pathogens in this study were C. albicans and C. glabrata [13,14,15]. Obese patients had slightly more C. glabrata, but this number was not significant. Obesity did not impact the choice of empiric antifungal therapy, although numerically more obese patients were treated with echinocandins. However, significantly more obese patients received an echinocandin as definitive therapy. This may be explained by the higher proportion of patients in this group with C. glabrata, the almost 10% less source control in the obese group, or the higher number of infectious diseases consults in the obese group.
The results of this study are comparable to published literature on overall outcomes associated with candidemia. First, in this study, the infection-related length of stay was a median of 13 days, which is similar to a study conducted among patients in internal medicine wards . Obese patients had an infection-related length of stay roughly 7 days longer than non-obese patients. Next, the duration of candidemia in this study was a median of 5 days, which is shorter than the 10 days reported in patients in an intensive care unit . However, obese patients had a significantly longer duration of candidemia, which may be responsible for the longer length of stay. Finally, the overall in-hospital mortality rate was 16.3%, which is lower than the 83% reported in intensive care units, but falls within the range of 5–71% that has been reported otherwise [17, 18]. Although there was no statistical difference in mortality between groups, one may argue that a 7% difference in mortality may be clinically relevant.
General risk factors for candidemia have been established, but limited information is available related to risk factors for clinical failure [16, 19]. Compared with general reports of successful treatment in 70% of patients, our rates of clinical failure of 65–75% are high . This is likely due to discrepancies in definitions of success and failure between studies.
Although limited information is available on the impact of obesity in candidemia, several studies have been published related to the effect of obesity in other infectious diseases with mixed results [21,22,23]. In one study, obesity was associated with decreased 30-day mortality in pneumonia, but had no impact on mortality in urinary tract infections, skin infections, or bloodstream infections . No differences in length of stay or requirement for intensive care were found between obese and non-obese groups. In a second study, higher BMI was associated with increased risk of all-cause mortality and organ failure in patients with gram-negative bloodstream infections . Finally, in obese patients with sepsis, all-cause mortality was lower, length of stay was longer, and hospital costs were higher than in non-obese patients . Taken together, these results lend support to the findings of increased mortality and length of stay in obese patients with Candida bloodstream infections that were found in this study.
This study is not without limitations. First, this study was retrospective, which is prone to selection bias and confounding variables. In this trial, all patients who met inclusion criteria during this period were included, limiting selection bias. In addition, standard definitions were used, and these were applied consistently between obese and non-obese groups. Demographics, comorbidity scores, and severity of illness scores were compared between groups and found to be similar, which should limit confounding variables. Next, this study was small and performed at a single center, which may limit the generalizability of these results to other centers or those with a different Candida epidemiology or patient case mix. However, the included patients were representative of obese populations, those found at academic medical centers, and those with Candida bloodstream infections.