Effect of Gabapentin on Kidney Function Following Laparoscopic Sleeve Gastrectomy (LSG)

Obesity is an important risk factor for kidney disease because it is strongly associated with diabetes and hypertension, two major causes of end-stage kidney disease (ESKD). Adults with severe obesity are at increased risk of diabetes compared with lean individuals. Laparoscopic sleeve gastrectomy (LSG) is an established surgical treatment for obesity and obesity-related diseases.

Acute kidney injury (AKI) is an important postoperative complication associated with prolonged hospital stay, increased hospital costs, higher mortality, and an increased risk of subsequent chronic kidney disease. Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used postoperatively and may contribute to renal adverse effects in susceptible patients.

Gabapentin is an anticonvulsant widely used for neuropathic pain and has also been investigated in the perioperative setting for reducing postoperative pain and opioid requirements. Experimental studies have suggested that gabapentin may influence pathways related to oxidative stress and renal injury; however, its effects on perioperative renal stress in clinical settings remain uncertain.

Neutrophil gelatinase-associated lipocalin (NGAL) and Dickkopf-3 (DKK3) were evaluated as biomarkers of renal stress and kidney injury. NGAL has been investigated as an early biomarker of AKI, whereas urinary DKK3 has been proposed as a marker of renal tubular stress and risk of kidney injury.

The study included 90 participants. Sixty participants undergoing LSG were randomized in a 1:1 ratio to LSG without preoperative gabapentin or LSG after a single 1200-mg oral dose of gabapentin approximately 1 hour preoperatively. An additional 30 participants with severe obesity who did not undergo surgery served as a non-randomized external reference cohort. Blood and urine samples were obtained at baseline, 24 hours postoperatively, and 6 months after surgery in the randomized surgical groups, whereas the external reference cohort underwent a single assessment at enrollment.

Inclusion criteria

• Age: 18-65 years old.
• Participants with severe obesity (BMI ≥40 kg/m², without comorbidities or BMI ≥35 kg/m², in the presence of obesity-related comorbidities).
• Preserved kidney function at baseline.
• For the randomized surgical cohort (Groups II and III), participants with severe obesity scheduled to undergo laparoscopic sleeve gastrectomy.
• For the non-randomized external reference cohort (Group I), participants with severe obesity who did not undergo laparoscopic sleeve gastrectomy during the study period or receive the study intervention.
• Both sexes.

Exclusion criteria

• Advanced cancer receiving active treatment.
• End-stage renal, hepatic, or cardiopulmonary disease.
• Untreated schizophrenia or cognitive impairment.
• Use of psychiatric medications, as specified in the study protocol.
• Active substance abuse.
• Chronic use of gabapentin or known hypersensitivity to gabapentin.
• Pregnancy or breastfeeding.
• Use of medications that could interfere with the assessed study parameter