Influence of Hypocaloric Diet on Urinary Lithogenic Factors of Obese Patients With Kidney Stones

University of Sao Paulo General Hospital

Status: Completed

Conditions: Kidney Stones; Obesity

Treatments: Behavioral: Hypocaloric diet

Study type: Interventional

Funder types: Other

Identifiers

NCT02690662

FAPESP 2015/04998-1

Details and patient eligibility

About

The objective of this study is to evaluate the influence of low-calorie diet on serum and urinary metabolic parameters of obese adults with urinary calculi and lithogenic metabolic abnormalities.

Full description

Objective: to evaluate the influence of low-calorie diet on serum and urinary metabolic parameters of obese adults with urinary calculi and lithogenic metabolic abnormalities.

Method: prospective study of 50 patients, aged over 18 years, with a body mass index above 30 kg/m2, urinary calculi and lithogenic metabolic abnormalities. Will be excluded from the study patients with psychiatric diagnoses other than depression, patients with inability to attend to clinical follow-up, patients with nephrocalcinosis, patients with urinary tract infection, patients with cystinuria and patients subjected to previous surgeries to treat obesity. Each patient will be evaluated monthly on the same day by urologist and nutritionist. On the first evaluation, will be done anamnesis, anthropometric measurements of weight, height, waist, bioimpedance and requested total serum calcium, phosphate, sodium, potassium, urea, creatinine, uric acid, and PTH, pH venous blood, urine tests type I, culture of urine and urine tests of calcium, oxalate, phosphate, sodium, potassium, citrate, magnesium, creatinine, uric acid, cystine and computed tomography for evaluation of urinary calculus. In the second evaluation, 30 days after, anthropometric measures will be repeated, bioimpedance and nutritional assessment will be made with recommendation of daily ingestion of 2500 ml of water and low-calorie diet of 16 Kcal/kg bw/day and requested total serum calcium, phosphate, sodium, potassium, urea, creatinine, uric acid, and PTH, pH venous blood, urine tests type I, culture of urine and urine tests of calcium, oxalate, phosphate, sodium, potassium, citrate, magnesium, creatinine, uric acid, cystine. Patients will be monitored monthly for 3 months with anthropometric measurements, bioimpedance and strengthening of nutritional recommendations. By the end of the third month, patients will be submitted to two series of serum and urine tests as before the diet. The results of serum and urine tests from the beginning of dietary treatment will be compared to those of the end of the treatment with Student T test. P<0.05 are considered significant.

Enrollment: 50 patients

Sex: All

Ages: 18 to 60 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• body mass index above 30 kg/m2 and urinary calculi on tomography and lithogenic metabolic abnormalities.

Exclusion criteria

• psychiatric diagnoses other than depression
• inability to attend to clinical follow-up
• nephrocalcinosis
• urinary tract infection
• cystinuria
• previous surgeries to treat obesity

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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50 participants in 1 patient group

Obese with kidney stones

Experimental group

Description:

Hypocaloric diet for 3 months

Treatment:

Behavioral: Hypocaloric diet