Changes in Anthropometric, Metabolic, and Micronutrient Features Among Patients with Severe Obesity Awaiting Metabolic and Bariatric Surgery

BACKGROUND AND OBJECTIVE: Due to high demand for metabolic and bariatric surgery, patients often face significant waiting periods before undergoing the procedure. This study aimed to investigate trends in weight and metabolic changes among patients with severe obesity awaiting surgery, given the potential impact of preoperative metabolic changes on perioperative outcomes. METHODS: This retrospective cohort study included patients with severe obesity who had been waiting for metabolic and bariatric surgery for at least six months. Weight, body composition analysis parameters, and biochemical tests were recorded every six to eight weeks for these candidates. RESULTS: Among the 2926 patients studied, the average age was 39.7 years, with 74.8% being women. The mean weight was 124.65 kg, while the mean BMI was 46.14 kg/m². Seventy-five percent of the patients had obesity-related comorbidities. Adjusted models based on generalized estimating equations (GEE) approach showed that weight, FBS, insulin, and TG have an increasing trend over time. Male sex was associated with significantly higher weight (+25.78 kg), FBS (+4.11 mg/dL), insulin (+8.47 µIU/mL), TG (+15.39 mg/dL), SGPT (+17.59 IU/L), and SGOT (+6.93 IU/L), as well as lower HDL (-3.89 mg/dL), and a small but statistically significant increase in BUN. Age showed small but significant effects, with increases linked to reduced weight, insulin, TG, and SGPT, but slightly higher FBS, LDL, HDL, and BUN values. Dyslipidemia was significantly associated with higher TG (+38.20 mg/dL), while type 2 diabetes mellitus was linked to large increases in FBS (+61.63 mg/dL) and TG (+18.04 mg/dL) and a decrease in LDL (-7.50 mg/dL). The presence of cardiovascular disease was related to higher insulin (+7.22 µIU/mL), but lower TG (-4.02 mg/dL) and LDL (-13.84 mg/dL). CONCLUSION: Lengthening the waiting time for surgery can lead to worsening glycolipid status and weight gain in patients. Therefore, if possible, reducing wait times or providing more regular and thorough nutritional and psychological consultations can improve metabolic conditions, resulting in better outcomes after surgery.