Association of body mass index with the outcomes of retrograde intrarenal surgery

Abstract

Objective: Overweight and obesity increased worldwide over four decades. In 2016, nearly 11% of men and 15% of women over 18 years old were obese. Obesity is accepted as a risk factor for renal stones. The relationship between obesity and urolithiasis is complicated. Various complications can occur during perioperative or postoperative follow-up in obese patients. Minimal invasive nature and high efficacy of Retrograde Intrarenal Surgery (RIRS) present itself as a safe and less morbid treatment option. In this study, we aimed to compare the efficacy and safety of RIRS in the treatment of kidney stones in different BMI levels. Material and Methods: Files of 552 patients who underwent RIRS for renal stones between January 2012 and December 2017 were reviewed. We classified patients according to the World Health Organisation classification. These three groups were compared for stone-free rate, complication rate, operative and fluoroscopy times and length of hospital stay. Results: The stone-free rate (SFR) of the study population was 80.8%. It was 81% for Group 1, 83.7% for Group 2 and 77.7% for Group 3. There was no statistically significant difference between the three groups among SFR (p=0.346). Clinical insignificant residual fragments (CIRF) status was also similar among the three groups (p=0.254). Complication rates between the three groups were statistically similar (p=0.416). Conclusion: In this study, we have shown that RIRS is a suitable option for all urolithiasis patients, even for obese individuals. Stone-free rates, length of hospital stay, operation time and complication rates in obese patients are similar with non-obese patients. Keywords: urolithiasis; obesity; laser lithotripsy