"ANATOMICAL & PHYSIOLOGICAL CHANGES, HORMONAL SHIFTS AND NUTRITIONAL DEFICIENCIES AFTER SLEEVE GASTRECTOMY"

Abstract

Sleeve gastrectomy (SG) is a widely adopted bariatric procedure that promotes significant weight loss and metabolic improvement in obese individuals. However, this surgical intervention alters gastrointestinal anatomy and physiology, influences hormonal secretions, and may predispose patients to nutritional deficiencies. Despite its widespread use, there is limited clinical data from cross-sectional evaluations detailing these multifaceted changes in post-operative patients.

Objective: To assess the anatomical and physiological changes, hormonal alterations, and prevalence of nutritional deficiencies in patients 6 to 18 months post-sleeve gastrectomy in a tertiary care setting.

Methodology: A cross-sectional clinical study was conducted on 112 adult patients (aged 20–55 years) who underwent laparoscopic sleeve gastrectomy between January 2024 to June 2025 at a tertiary care hospital Lahore. Data collection included clinical evaluation, anthropometric measurements, laboratory investigations (complete blood count, serum ferritin, vitamin B12, folate, vitamin D, calcium), and hormonal profiling (ghrelin, GLP-1, insulin). Upper GI endoscopy and abdominal ultrasound were used to evaluate anatomical changes and gastric motility. Statistical analysis was performed using SPSS v25, with significance set at p<0.05. Results: Mean BMI decreased significantly from 42.3±5.6 kg/m² preoperatively to 30.1±4.2 kg/m² postoperatively (p<0.001). Endoscopic findings revealed delayed gastric emptying in 18.7% and reduced gastric volume in all patients. Serum ghrelin levels were reduced by 68% postoperatively, while GLP-1 and insulin sensitivity showed marked improvement (p<0.01). Nutritional deficiencies were prevalent: vitamin B12 deficiency in 34.8%, iron deficiency in 29.5%, vitamin D deficiency in 46.4%, and folate deficiency in 18.7% of patients. A significant correlation was found between deficiency prevalence and time elapsed since surgery. Conclusion: Sleeve gastrectomy results in significant anatomical and hormonal alterations that contribute to weight loss and metabolic improvement. However, it also poses a risk for multiple micronutrient deficiencies, particularly in vitamin B12, iron, and vitamin D. Regular post-operative monitoring and individualized nutritional supplementation are essential to mitigate long-term complications and optimize clinical outcomes.