Effect of the body mass index on outcomes of flexible ureterorenoscopy

Abstract

The aim of the study to compare outcomes of flexible ureterorenoscopy in patients with different body mass index (BMI) scores and to explore whether the BMI has an effect on outcomes of RIRS. Five hundred and two patients who underwent flexible URS in 3 centers between 2008 and 2012 for the management of single upper urinary tract calculi were retrospectively reviewed. Patients were categorized as normal weight BMI 18.5 to 24.99 kg/m(2), overweight 25 to 29.99 kg/m(2), obese 30 to 39.99 kg/m(2) and morbid obese >40 kg/m(2).The groups were assessed in terms of demographic parameters including age, gender, stone size, intraoperative and postoperative variables. The mean patient age was 41.3 ± 15.51 (18-81) years and with an average BMI 26.68 ± 5.2 kg/m(2) (16.64-55.15 kg/m²). Of the patients, 43.2 % had normal weight (NW), 32.2 % were overweight (OW), 21.9 % were obese (O) and 2.5 % were morbidly obese (MO). Stone-free rates after single procedure in NW, OW, O, MO groups were 60.8, 61.7, 73.6, 61.5 %, respectively (p = 0.079). Overall targeted stone-free rates were also similar in four groups (88.9, 90.1, 93.6, 90.4 %, p = 0.586). There were no statistically significant differences in the frequency of complications and mean hospitalization time among the groups (p > 0.05). In conclusion, this study demonstrated that flexible URS is a valuable option for the treatment of kidney stone in both obese and non-obese patients. BMI did not influence the postoperative outcomes.

Nephrolithiasis in the Obese Patient

“…However, in a subanalysis, FURS had poorer SFR in obese patients for stones > 20 mm [46]. However, multiple further studies have found no difference in SFR with URS for normal-weight patients (60.8-70.7%) compared with obese patients (65-79.4%) [47][48][49], even for large stone sizes (> 20 mm) [48]. There was also no significant difference between complication rates for normal-weight patients and obese patients [47,49].…”

Flexible Ureterorenoscopy for Treatment of Kidney Stones: Establishment as Primary Standard Therapy in a Tertiary Stone Center

“…A high BMI additionally influenced the outcome of ESWL negatively due to difficult stone location and increased skin-to-stone distance with attenuation of the application of shock wave energy [25]. Sari et al [11] investigated the effect of the BMI on outcome of fURS. The average BMI was 26 with a distribution of normal weighted patients being 43%, overweight 32%, obese 22% and morbidly obese 3%.…”

“…In addition, successful ESWL is dependent on skin-to-stone distance, resulting in poorer results in obese patients [10]. In contrast, no negative influence regarding body mass index (BMI) on the stone free rate was documented for fURS [11]. …”

Retrograde intrarenal surgery for renal stones - Part 2

“…The efficiency of fURS for obese and morbidly obese patients has been evaluated in various studies, and SFR and complication rates were found to be not affected by body mass index. [27][28][29] …”