Obesity and SARS-CoV-2 infection have both been associated with renal injury through inflammatory, endothelial, and microvascular mechanisms. Whether a history of COVID-19 modifies renal trajectories after metabolic surgery remains unclear. To evaluate the association between prior COVID-19 infection and renal outcomes 12 months after laparoscopic Roux-en-Y gastric bypass (LRYGB). We conducted a prospective cohort study including 38 adults with severe obesity (BMI ≥ 35 kg/m² with comorbidities or ≥ 40 kg/m²) and preserved baseline kidney function who underwent LRYGB between January 2022 and January 2024. Participants were stratified according to a history of laboratory-confirmed COVID-19 infection. Renal outcomes included measured and estimated glomerular filtration rate, creatinine and urea clearance, 24-h proteinuria, albuminuria, and urine albumin-to-creatinine ratio (ACR). KDIGO combined G/A risk categories were assessed at baseline and 12 months. Longitudinal changes were explored using within-group analyses and between-group comparisons of trajectories. Eighteen patients (47%) had a history of COVID-19 infection. Weight loss and metabolic response were comparable between groups (BMI 44 ± 6 to 29 ± 5 kg/m²; p < 0.01). Classical renal function parameters remained stable in both groups. ACR decreased significantly over time only among patients without prior COVID-19 infection (14 ± 14 to 7 ± 6 mg/g; p = 0.03), whereas the reduction did not reach statistical significance in previously infected patients (12 ± 10 to 10 ± 10 mg/g; p = 0.20). However, formal between-group analyses did not demonstrate a statistically significant difference in renal trajectories. LRYGB was associated with substantial weight loss and stable renal function at 12 months regardless of prior COVID-19 infection. A differential within-group pattern in albuminuria improvement was observed, but between-group differences were not statistically significant. These findings should be interpreted as exploratory and hypothesis-generating, highlighting the need for larger studies with longer follow-up and mechanistic biomarkers to clarify renal outcomes after metabolic surgery in patients with a history of COVID-19 infection.
García et al. (Thu,) studied this question.