Analysis of morbidity and mortality from complications of bariatric surgery in Brazil - an integrative literature review

Abstract

Objective: To highlight the main complications of bariatric surgery, as well as their impact on patient morbidity and mortality. Method: This study is a literature review, and the data evaluation method consisted of six steps: guiding question, database search, data collection, critical appraisal of the included studies, discussion of the results, and presentation of the literature review. The inclusion criteria were articles in Portuguese and English, published between 2016 and 2025, freely available in full, and addressing the topic of bariatric surgery, its complications, and its impact on morbidity and mortality. Exclusion criteria included any work that did not meet the aforementioned inclusion criteria. Results: Bariatric surgery offers many benefits in reducing mortality from severe obesity and improving parameters in Chronic Noncommunicable Diseases (NCDs). Complications resulting from this surgical procedure can be divided according to postoperative time as early (up to 30 days), immediate (up to 6 months), and late (more than 6 months). Regarding outcomes, we can list complications inherent to surgical procedures, such as hemorrhage, anastomotic fistulas, deep vein thrombosis, pulmonary embolism, and internal hernias. Furthermore, in the nutritional context, bariatric surgery can lead to micronutrient deficiencies (vitamins D, B1, B12, iron, and folic acid). These deficiencies can cause general anemia, asthenia, peripheral neuropathy, and cognitive impairment, but can also lead to specific conditions such as Wernicke-Korsakoff syndrome, linked to low vitamin B1 levels. In addition to these complications, postprandial hypoglycemia is another common condition that can occur postoperatively after bariatric surgery. In addition, the patient may also develop psychological and behavioral impairments. Some studies included in this literature review highlighted alcohol abuse as a possible compensatory mechanism for binge eating or even changes in the anatomical and physiological processes of absorption. Regarding surgical techniques, vertical gastrectomy (SG) has seen an increase in its performance rate in Brazil, with lower rates of immediate complications. However, a stronger link between this and the development of gastroesophageal reflux and gastritis in bariatric patients was observed. Roux-en-Y Gastric Bypass (RYGB) is highly effective in sustained weight loss, but it is more frequently associated with metabolic and behavioral complications. Conclusion: This study allowed us to understand the benefits of bariatric surgery and highlighted the complications associated with the procedure, which can directly impact patients' morbidity, mortality, and quality of life.