Effect of a low-calorie diet on 24-hour urinary parameters of obese adults with idiopathic calcium oxalate kidney stones

Author(s)

Alexandre Danilovic ^[1] ; Giovanni Scala Marchini ^[2] ; Nidia Denise Pucci ^[3] ; Brian Coimbra ^[4] ; Fabio Cesar Miranda Torricelli ^[5] ; Carlos Batagello ^[6] ; Fabio Carvalho Vicentini ^[7] ; Miguel Srougi ^[8] ; William C. Nahas ^[9] ; Eduardo Mazzucchi ^[10]

Affiliation

^[1] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Urologia - Brasil

^[2] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Nutrição - Brasil

^[3] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Nutrição - Brasil

^[4] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Urologia - Brasil

^[5] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Urologia - Brasil

^[6] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Urologia - Brasil

^[7] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Urologia - Brasil

^[8] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Urologia - Brasil

^[9] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Urologia - Brasil

^[10] Faculdade de Medicina da Universidade de São Paulo. Hospital das Clínicas. Departamento de Urologia - Brasil

• Document type: Journal article
• Source: INTERNATIONAL BRAZ J UROL; v. 47, n. 6, p. 1136-1147, 2021-10-01.

Abstract

ABSTRACT Purpose: to evaluate the effect of low-calorie diet on 24-hour urinary metabolic parameters of obese adults with idiopathic calcium oxalate kidney stones. Materials and Methods: Adult idiopathic calcium oxalate stone formers, with body mass index (BMI) ≥30kg/m2 and a known lithogenic metabolic abnormality, were submitted to low-calorie diet for twelve weeks. After enrolment, anthropometric measures, serum exams, 24-hour urinary metabolic parameters and body impedance were collected one month prior to dietary intervention and at the end of twelve weeks. Correlations between weight loss, waist circumference loss, fat loss and variation in 24-hour urinary lithogenic parameters and calcium oxalate urinary supersaturation (CaOx SS) as per Tiselius equation were analysed. Results: From January 2017 to January 2018, 39 patients were enrolled to participate in this study. Median (range) prescribed diet was 1300 (1100-2100) Kcal/day. Mean age was 51.7±11.0 (29-68) years old and 69.2% were female. 30.8% of the participants shifted from obesity to BMI <30kg/m2 and none to BMI <25kg/m2. A significant correlation was found between baseline 24-hour urinary oxalate and weight (p=0.018) and BMI (p=0.026). No correlation was found between variation of weight, waist circumference, fat mass and 24-h urinary stone risk factors or CaOx SS. Conclusions: Short-term modest weight loss induced by twelve weeks of low-calorie diet is not associated with a decrease of 24-hour urinary lithogenic parameters in idiopathic calcium oxalate stone formers. Calcium oxalate urinary stone formation is probably multifactorial and driven by other factors than weight. (AU)

• FAPESP's process: 15/04998-1 - Influence of low-calorie diet on metabolic parameters of obese patients with urinary stone disease
• Grantee: Brian Guilherme Monteiro Marta Coimbra
• Support Opportunities: Scholarships in Brazil - Scientific Initiation