Association between small intestinal bacterial overgrowth and cardiac function in patients with chronic heart failure
ZHANG Xian1， QI Xiang2， DONG Xinyue1， SONG Yu1， XU Yamei1，LU Feixin 1， ZHANG Qian1， XIAO Huahua3， LIN Ying1
(1. Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai 200032； 2. School of Nursing, Fudan University, Shanghai 200032； 3. Department of Endocrinology, the First Affiliated Hospital of Sun Yatsen University, Guangzhou Guangdong 510080,China)
Objective: To investigate the association between small intestinal bacterial overgrowth（SIBO） and the severity of heart failure in chronic heart failure（CHF）patients. Methods: A total of 160 CHF patients admitted to the Department of Cardiology of Zhongshan Hospital were recruited as the CHF group, and 50 nonCHF patients admitted in the same period were selected as the control group. Lactulose hydrogen breath test（LHBT）was used to compare the incidence of SIBO between the CHF group and the control group; in addition, the association between the severity of heart failure（NYHA cardiac function classification）and the positivity of SIBO in patients with CHF was also analyzed. The association between SIBO positivity and clinical characteristics of CHF patients was further analyzed, and the ordered multi-categorical Logistic regression was used to screen the factors associated with the severity of heart failure in CHF patients. Results: ① The positive rate of SIBO in patients with CHF（53.8%）was significantly higher than that in the control group（32.0%， x2=7.214，P<0.01). ② The positive rates of SIBO in NYHA cardiac function class Ⅰ-Ⅳ patients were 20.0%, 36.5%, 66.7% and 71.4%, respectively, with statistically significant differences（x2=16.820，P<0.01). ③ C reactive protein, NT-proBNP and pulmonary artery pressure in SIBO positive group were significantly higher than those in SIBO negative group（all P<0.05). The incidences of jugular vein distention, pulmonary rales and lower limb edema in SIBO positive group were 29.1%, 24.4% and 46.5%, respectively, which were significantly higher than those in SIBO negative group（all P<0.05). ④ The positivity of SIBO was significantly associated with the aggravation of cardiac function class（OR=2.661, 95% CI：1.30-5.45, P=0.007). Conclusion: The positivity of SIBO is associated with CHF, and the incidence of SIBO in CHF patients increases with the severity of heart failure.
