Sex, BMI, preoperative FIB-4 index, and iron supplementation were associated with postoperative anemia after laparoscopic sleeve gastrectomy among 619 Chinese patients: a retrospective cohort study.

INTRODUCTION

Laparoscopic sleeve gastrectomy (LSG) has become a common bariatric procedure in China, and the long-term risk of postoperative anemia remains to be estimated. This study aimed to investigate the incidence and risk factors of anemia at different times after LSG in Chinese population.

OBJECTIVES

To investigate the incidence of postoperative anemia and its risk factors in a cohort of Chinese patients with obesity undergoing LSG.

SETTING

Huashan Hospital, Fudan University, Shanghai, China.

METHODS

A retrospective cohort study was conducted on 619 patients who underwent LSG at a tertiary hospital between 2012 and 2022. The incidence of anemia at different postoperative stages was reported, and risk factors were explored using multivariable logistic regression.

RESULTS

Among the 619 patients, 567, 436, and 189 participated in 0∼3, 3+∼12, and 12+∼60 months follow-up visits, respectively. The cumulative incidence of anemia for each period were 9.3%, 6.6%, and 9.1% for males, lower than those of 13.5%, 20.6%, and 39.2% for females. During the first 3 months of follow-up, preoperative iron deficiency was associated with a higher incidence of postoperative anemia (odds ratio [OR]: 3.67, 95% confidence interval [CI]: 1.11-12.16), and iron supplementation was associated with a lower risk of anemia among all patients (.46, .27-.77) and female patients (.49, .27-.87). In the period of 3+ - 12 months, females with advanced FIB-4 level (≥1.45, an index for liver fibrosis) had a higher incidence of anemia (5.72, 1.24-26.49). Among males, higher preoperative body mass index (BMI) was associated with a lower risk (.79, .64-.98), while weight loss was positively associated with anemia (1.26, 1.06-1.48).

CONCLUSION

Postoperative anemia was frequent in Chinese patients undergoing LSG and was associated with female gender, lower BMI, advanced preoperative FIB-4 level, and a lack of iron supplementation after surgery.