Roux-en-Y gastric bypass has a significant impact on improving clinical outcomes for patients with nonalcoholic fatty liver disease, a West Virginia University study found. The study, led by Dr Shailendra Singh, included thousands of patients diagnosed with NAFLD, a condition that is seeing an upsurge and contributes to multiple other afflictions.
"NAFLD is one of the most common causes of liver disease in the United States," said Singh, associate professor and director of bariatric endoscopy in the WVU School of Medicine. "The global prevalence of NAFLD has reached 25% and is projected to be more than 33% by 2030. NAFLD is closely associated with obesity and metabolic syndrome, and it can lead to various complications, such as liver cirrhosis, cancer and cardiovascular diseases. Our study provides critical data about the impact of bariatric surgery on patients with NAFLD and supports its use as a therapeutic modality to improve clinical outcomes."
While bariatric surgery has long been associated with reducing cardiovascular disease and death in patients with obesity, the research team set out to explore whether the same held true for patients with NAFLD.
"Obesity is a significant risk factor for cardiovascular disease, one of the leading worldwide mortality causes," explained Singh. "Bariatric surgery is an effective weight-loss intervention in patients with obesity."
The study included patients who received either Roux-en-Y gastric bypass or sleeve gastrectomy. Patients with a history of gastric banding and other less common bariatric procedures were excluded.
The study group included 9,374 adult patients with NAFLD and obesity, classified as having a body mass index of 35 or greater. The patients were divided into two groups of 4,687 each, those who underwent bariatric surgery and the nonsurgical control group. Patients in the surgical group were matched with those in the control group according to age, demographics, medication and comorbidities, having two or more chronic or long-term conditions simultaneously.
"We then studied the risk of major cardiovascular events such as heart failure, myocardial infarction, stroke or need for cardiac surgeries and death in both groups," Singh said.
The BS group had significantly lower risk of new-onset of heart failure (HR, 0.60; 95% CI, 0.51-0.70), cardiovascular events (HR, 0.53; 95% CI, 0.44-0.65), cerebrovascular events (HR, 0.59; 95% CI, 0.51-0.69) and coronary artery interventions (HR, 0.47; 95% CI, 0.35-0.63), compared with the non-BS group. Similarly, all-cause mortality was substantially lower in the BS group (HR, 0.56; 95% CI, 0.42-0.74).
The total number of patients who remained in follow-up was 3,679 patients in the BS group and 3,727 patients in the non-BS group at the end of 1 year, 2,092 patients in the BS group and 2,133 patients at the end of 3 years, 1056 patients in the BS group and 1,069 patients in the non-BS group at the end of 5 years, and 769 patients in the BS group and 516 patients in the non-BS group at the end of 7 years. These outcomes were consistent at follow-up durations of one, three, five and seven years.
Within 30 days after bariatric surgery, 271 patients (5.8%) experienced postoperative complications. Complications included postprocedural haemorrhage (51 patients [1.1%]), gastrointestinal leak (61 patients [1.3%]), postoperative sepsis (58 patients [1.2%]), venous thromboembolism (19 patients [0.4%]), small bowel obstruction (36 patients [0.8%]), acute postprocedural respiratory failure (12 patients [0.2%]) and acute kidney injury (53 patients [1.1%]).
The findings of this cohort study suggest that surgery was associated with a lower incidence of major adverse cardiovascular events and all-cause mortality in patients with NAFLD and obesity. Although the study provides novel information, the researchers called for further randomised clinical trials and additional observational studies are needed to corroborate their findings.
"The multifaceted nature of NAFLD with varying coexisting complications makes its treatment complex," he added. "We hope that our study findings will lead to increased awareness of the benefits of bariatric surgery and its role in the management of patients with NAFLD and obesity."
The findings were reported in the paper, ‘Cardiovascular Outcomes and Mortality After Bariatric Surgery in Patients With Nonalcoholic Fatty Liver Disease and Obesity’, published in JAMA Network Open.
To access this paper, please click here