Impact of a preoperative low-calorie diet on liver histology in patients with fatty liver disease undergoing bariatric surgery

Risa M Wolf; Kiyoko Oshima; Joseph K Canner; Kimberley E Steele

doi:10.1016/j.soard.2019.08.013

Impact of a preoperative low-calorie diet on liver histology in patients with fatty liver disease undergoing bariatric surgery

Surg Obes Relat Dis. 2019 Oct;15(10):1766-1772. doi: 10.1016/j.soard.2019.08.013. Epub 2019 Aug 22.

Authors

Risa M Wolf¹, Kiyoko Oshima², Joseph K Canner³, Kimberley E Steele⁴

Affiliations

¹ Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland; The Center for Metabolism and Obesity Research, Johns Hopkins University School of Medicine, Baltimore, Maryland. Electronic address: RWolf@jhu.edu.
² Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
³ Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
⁴ Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland; Division of Health, Behavior and Society, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.

PMID: 31558407
DOI: 10.1016/j.soard.2019.08.013

Abstract

Background: A low-calorie diet (LCD) before bariatric surgery has been shown to reduce liver volume and facilitate ease of operation. It is estimated that 75%-100% of individuals undergoing bariatric surgery have nonalcoholic fatty liver disease (NAFLD).

Objectives: We aimed to investigate how an LCD affects liver histology in the setting of NAFLD.

Setting: University Hospital, United States.

Methods: Forty intraoperative liver specimens were analyzed histologically as follows: 20 with and 20 without a preoperative 2-week, 1200 kcal/d LCD. Weight was measured prediet, at surgery, and 6 months after surgery. NAFLD activity score was used to grade liver histology at surgery. The NAFLD activity score scores steatosis, lobular inflammation, hepatocellular ballooning, and fibrosis.

Results: The non-LCD group (n = 20) had mean weight at surgery of 136.1 ± 24.1 kg. The LCD group (n = 20) had initial mean weight of 128.6 ± 25.4 kg, with presurgical weight loss of 3.43 kg (range, 0-9.3 kg), mean change in body mass index 1.24 kg/m² (2.66% total weight loss) on an LCD. The LCD group had significantly less steatosis (P = .02), fewer foci of lobular inflammation (P = .01), and less hepatocellular ballooning (P = .04) compared with the non-LCD group; with no difference in degree of fibrosis. Fewer patients in the LCD group had nonalcoholic steatohepatitis with ballooning (P = .04). Weight loss on an LCD before bariatric surgery was predictive of weight loss 6 months after surgery (P = .026).

Conclusions: A 2-week LCD before bariatric surgery is associated with significant improvement in steatosis, inflammation, and hepatocellular ballooning in NAFLD. Among LCD patients, preoperative weight loss was associated with improved 6-month weight loss and liver function.

Keywords: Bariatric surgery; Liver histology; Low-calorie diet; Nonalcoholic steatohepatitis; Preoperative weight loss.

MeSH terms

Adult
Bariatric Surgery*
Caloric Restriction*
Cohort Studies
Female
Humans
Liver / pathology
Male
Middle Aged
Non-alcoholic Fatty Liver Disease* / complications
Non-alcoholic Fatty Liver Disease* / pathology
Obesity, Morbid* / complications
Obesity, Morbid* / diet therapy
Obesity, Morbid* / surgery
Preoperative Care / methods*
Preoperative Period
Weight Loss
Young Adult