Background: Percutaneous nephrolithotomy (PCNL) has been widely used to treat renal stones. The application of PCNL in obese patients results in the emergence of a number of challenges. This study compared the effect of obesity on the outcomes of PCNL in kidney stone treatment. Methods: Eligible studies were searched in PubMed, Web of Science, and Cochrane Library databases. Data were analyzed using RevMan statistical software, weighted mean differences, ORs, and 95% CIs were calculated. Results: Seven studies involving 2,720 normal-weight, 1,686 obese, and 286 super-obese individuals were included in this meta-analysis. A pooled analysis of safety revealed that no obvious differences in terms of complication rates after treatment existed between obese and normal-weight individuals (OR 0.97, 95% CI 0.80-1.16, p = 0.73), and between super-obese and normal-weight individuals (OR 0.88, 95% CI 0.61-1.27, p = 0.49). A pooled analysis of effectiveness revealed that no obvious difference in terms of stone-free rate after treatment existed between obese and normal-weight individuals (OR 0.98, 95% CI 0.84-1.15, p = 0.79), and between super-obese and normal-weight individuals (OR 1.20, 95% CI 0.88-1.63, p = 0.25). Moreover, no obvious differences in terms of length of hospital stay after treatment existed between super-obese and normal-weight individuals (95% CI -0.15 to 0.37, p = 0.39). Additionally, no obvious differences in terms of operation time existed between obese and normal-weight individuals (95% CI -3.36 to 1.17, p = 0.34). However, the operation time was longer among super-obese individuals than among normal-weight individuals (95% CI -22.64 to -1.40, p = 0.03), and the length of hospital stay was shorter among obese patients than among normal-weight patients (95% CI 0.04-0.34, p = 0.01). No publication bias was observed in this work. Conclusion: The PCNL performed in normal-weight, obese, and super-obese individuals for kidney stone treatment showed similar outcomes, except that operation time was longer among super-obese individuals and the hospital stay was shorter in obese individuals than in other groups. Thus, PCNL is a safe and efficacious treatment for renal stones in patients of all sizes.

Keywords:
Renal stones, Percutaneous nephrolithotomy, Obesity, Complications, Stone-free rate, Operative time, Length of hospital stay
1.
Djalalinia S, Qorbani M, Peykari N, Kelishadi R: Health impacts of obesity. Pak J Med Sci 2015;31:239-242.
2.
Musaiger AO: Overweight and obesity in eastern Mediterranean region: prevalence and possible causes. J Obes 2011;2011:407237.
3.
Djalalinia S, Kelishadi R, Qorbani M, Peykari N, Kasaeian A, Nasli-Esfahani E, et al: A systematic review on the prevalence of overweight and obesity, in Iranian children and adolescents. Iran J Pediatr 2016;26:e2599.
4.
Taylor EN, Stampfer MJ, Curhan GC: Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up. J Am Soc Nephrol 2004;15:3225-3232.
5.
Taylor EN, Stampfer MJ, Curhan GC: Diabetes mellitus and the risk of nephrolithiasis. Kidney Int 2005;68:1230-1235.
6.
Taylor EN, Stampfer MJ, Curhan GC: Obesity, weight gain, and the risk of kidney stones. JAMA 2005;293:455-462.
7.
Knoll T, Buchholz N, Wendt-Nordahl G: Extracorporeal shockwave lithotripsy vs. percutaneous nephrolithotomy vs. flexible ureterorenoscopy for lower-pole stones. Arab J Urol 2012;10:336-341.
8.
Javanmard B, Razaghi MR, Ansari Jafari A, Mazloomfard MM: Flexible ureterorenoscopy versus extracorporeal shock wave lithotripsy for the treatment of renal pelvis stones of 10-20 mm in obese patients. J Lasers Med Sci 2015;6:162-166.
9.
Mokhless IA, Abdeldaeim HM, Saad A, Zahran AR: Retrograde intrarenal surgery monotherapy versus shock wave lithotripsy for stones 10 to 20 mm in preschool children: a prospective, randomized study. J Urol 2014;191(5 suppl):1496-1499.
10.
Wang K, Zhang P, Xu X, Fan M. Ultrasonographic versus fluoroscopic access for percutaneous nephrolithotomy: a meta-analysis. Urol Int 2015;95:15-25.
11.
Şimşek A, Özgör F, Akbulut MF, Küçüktopçu O, Berberoğlu AY, Sarılar Ö, Binbay M, Müslümanoğlu AY: Does body mass index effect the success of percutaneous nephrolithotomy? Turk J Urol 2014;40:104-109.
12.
Torrecilla Ortiz C, Meza Martínez AI, Vicens Morton AJ, Vila Reyes H, Colom Feixas S, Suarez Novo JF, et al: Obesity in percutaneous nephrolithotomy. Is body mass index really important? Urology 2014;84:538-543.
13.
El-Assmy AM, Shokeir AA, El-Nahas AR, Shoma AM, Eraky I, El-Kenawy MR, et al: Outcome of percutaneous nephrolithotomy: effect of body mass index. Eur Urol 2007;52:199-204.
14.
Bagrodia A, Gupta A, Raman JD, Bensalah K, Pearle MS, Lotan Y: Impact of body mass index on cost and clinical outcomes after percutaneous nephrostolithotomy. Urology 2008;72:756-760.
15.
Fuller A, Razvi H, Denstedt JD, Nott L, Pearle M, Cauda F, et al: The CROES percutaneous nephrolithotomy global study: the influence of body mass index on outcome. J Urol 2012;188:138-144.
16.
WHO Global Infobase: Data for Saving Lives. 2011. https://apps.who.int/infobase/?id_1 (accessed August 9, 2011).
17.
Shavit L, Ferraro PM, Johri N, Robertson W, Walsh SB, Moochhala S, et al: Effect of being overweight on urinary metabolic risk factors for kidney stone formation. Nephrol Dial Transplant 2015;30:607-613.
18.
Polat EC, Ozcan L, Cakir SS, Dursun M, Temur AO, Ozbek E: Relationship between calcium stone disease and metabolic syndrome. Urol J 2015;12:2391-2395.
19.
Singh P, Yadav S, Singh A, Saini AK, Kumar R, Seth A, Dogra PN: Systemic inflammatory response syndrome following percutaneous nephrolithotomy: assessment of risk factors and their impact on patient outcomes. Urol Int 2016;96:207-211.
20.
Biring MS, Lewis MI, Liu JT, Mohsenifar Z: Pulmonary physiologic changes of morbid obesity. Am J Med Sci 1999;318:293-297.
21.
Keheila M, Leavitt D, Galli R, Motamedinia P, Theckumparampil N, Siev M, et al: Percutaneous nephrolithotomy in super obese patients (body mass index ≥ 50 kg/m²): overcoming the challenges. BJU Int 2016;117:300-306.
22.
Koo BC, Burtt G, Burgess NA: Percutaneous stone surgery in the obese: outcome stratified according to body mass index. BJU Int 2004;93:1296-1299.
23.
Alyami FA, Skinner TA, Norman RW: Impact of body mass index on clinical outcomes associated with percutaneous nephrolithotomy. Can Urol Assoc J 2013;7:E197-E201.
24.
Ozgor F, Ucpinar B, Binbay M: Effect of obesity on prone percutaneous nephrolithotomy outcomes: a systemic review. Urol J 2016;13:2471-2478.
25.
Curtis R, Thorpe AC, Marsh R: Modification of the technique of percutaneous nephrolithotomy in the morbidly obese patient. Br J Urol 1997;79:138-140.
26.
Mazzucchi E, Vicentini FC, Marchini GS, Danilovic A, Brito AH, Srougi M: Percutaneous nephrolithotomy in obese patients: comparison between the prone and total supine position. J Endourol 2012;26:1437-1442.
27.
Xue W, Pacik D, Boellaard W, Breda A, Botoca M, Rassweiler J, et al: Management of single large nonstaghorn renal stones in the CROES PCNL global study. J Urol 2012;187:1293-1297.
28.
Bayar G, Kadihasanoglu M, Aydin M, Sariogullari U, Tanriverdi O, Kendirici M: The effect of stone localization on the success and complication rates of percutaneous nephrolithotomy. Urol J 2014;11:1938-1942.
29.
Sergeyev I, Koi PT, Jacobs SL, Godelman A, Hoenig DM: Outcome of percutaneous surgery stratified according to body mass index and kidney stone size. Surg Laparosc Endosc Percutan Tech 2007;17:179-183.
30.
Kuntz NJ, Neisius A, Astroza GM, Tsivian M, Iqbal MW, Youssef R, et al: Does body mass index impact the outcomes of tubeless percutaneous nephrolithotomy? BJU Int 2014;114:404-411.
31.
Yang RM, Bellman GC: Tubeless percutaneous renal surgery in obese patients. Urology 2004;63:1036-1040; discussion 1040-1041.
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2017
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