6.2.0.0 Adverse Effects
The safety of metabolic surgery has improved significantly over the past two decades, with continued refinement of minimally invasive approaches (laparoscopic surgery), enhanced training and credentialing, and involvement of multidisciplinary teams. Mortality rates with metabolic operations are typically 0.1%–0.5%, similar to cholecystectomy or hysterectomy (79-83,). Morbidity has also dramatically declined with laparoscopic approaches. Major complications rates (e.g., venous thromboembolism, need for operative reintervention) are 2%–6%, with other minor complications in up to 15% (79-88,), which compare favorably with rates for other commonly performed elective operations (83). Empirical data suggest that proficiency of the operating surgeon is an important factor for determining mortality, complications, reoperations, and readmissions (89).
Longer-term concerns include dumping syndrome (nausea, colic, and diarrhea), vitamin and mineral deficiencies, anemia, osteoporosis, and, rarely (90), severe hypoglycemia. Long-term nutritional and micronutrient deficiencies and related complications occur with variable frequency depending on the type of procedure and require life-long vitamin/nutritional supplementation (91,92). Postprandial hypoglycemia is most likely to occur with RYGB (92,93). The exact prevalence of symptomatic hypoglycemia is unknown. In one study, it affected 11% of 450 patients who had undergone RYGB or vertical sleeve gastrectomy (90). Patients who undergo metabolic surgery may be at increased risk for substance use, including drug and alcohol use and cigarette smoking. Additional potential risks of metabolic surgery that have been described include worsening or new-onset depression and/or anxiety, need for additional GI surgery, and suicidal ideation (94-97,).
People with diabetes presenting for metabolic surgery also have increased rates of depression and other major psychiatric disorders (98). Candidates for metabolic surgery with histories of alcohol, tobacco, or substance abuse; significant depression; suicidal ideation; or other mental health conditions should therefore first be assessed by a mental health professional with expertise in obesity management prior to consideration for surgery (99). Surgery should be postponed in patients with alcohol or substance abuse disorders, significant depression, suicidal ideation, or other mental health conditions until these conditions have been fully addressed. Individuals with preoperative psychopathology should be assessed regularly following metabolic surgery to optimize mental health management and to ensure psychiatric symptoms do not interfere with weight loss and lifestyle changes.