The assessment of 24 24-h urine volume by measurement of urine specific gravity with dipstick in adults with nephrolithiasis

Abstract

Background:Nephrolithiasis is a recurrent disease, and one of the most effective methods for prevention of stone recurrence is increasing the urine output (>2 L/day), but it is difficult to achieve it. The aim of this study was to evaluate the effect of behavioral intervention by measurement of urine specific gravity using dipstick on 24-h urine volume in first renal stone patients.Materials and Methods:In this prospective randomize clinical study, 80 adult patients with history of first renal stone were included. Patients were divided into two groups with 40 patients in each group. We explained the importance of high fluid intake and high urine volume in the prevention of renal stones for all patients. Group A patients were trained to measure 24-h urine volume every 15 days, and group B patients were trained to keep urine specific gravity below 1.010 by using dipstick. We measured 24-h urine volume in each group before intervention, and at 3 months and 6 months after intervention and compared them.Results:There were no significant differences between the two groups in 24-h urine volume before intervention (P = 0.41), but it was significant 3 months (P = 0.01) and 6 months (P = 0.01) after intervention. Patients’ compliance was 20% in group A and 90% in group B (P < 0.05).Conclusion:The use of behavioral modification with dipstick is an effective method for control and maintenance of optimal urine volume, and it has resulted in more patient compliance for drinking water and is more effective for prevention of renal stone.

A systematic review to determine the most effective interventions to increase water intake

“…Self‐monitoring tools were used in three of the studies and included patient‐led checking of urine volume and urine specific gravity (Table ). The study with the greatest increase in water intake (1550 mL or 145%) was a large 5 year RCT of patients with nephrolithiasis who were instructed to self‐monitor urine volume to achieve 2 L or more per day .…”

“…The study with the greatest increase in water intake (1550 mL or 145%) was a large 5 year RCT of patients with nephrolithiasis who were instructed to self‐monitor urine volume to achieve 2 L or more per day . Two studies that used dipsticks to self‐monitor urine specific gravity by patients with nephrolithiasis also achieved large increases in urine volume: 1200 mL (108%) over 6 months and 1300 mL increase (92%) over 2 months …”

“…The results from this systematic review indicate that all of the interventions carried out in the studies succeeded in increasing water intake. The studies of neutral quality suggest that the most helpful interventions to maintain adherence in the long term included specific instructions on water intake and the use tools to self‐monitor water intake, such as dipsticks to measure urine specific gravity or measurement of urine volume. Moreover, studies that instructed on the amount and frequency of water intake (specifically instructions to drink 500 mL water three times throughout the day or before meals) had more consistent changes in behaviour to consume fluid.…”

“…Sample sizes varied from 5 to 2877 participants, aged between 18 to 80 years, comprised of both genders, with and without co-morbidities. Only three studies examined the efficacy of increasing water intake in ADPKD patients [10][11][12] and one in CKD 13 , with the purpose of the remaining studies varying from the secondary prevention of recurrent kidney stones (n = 6) [14][15][16][17][18][19] ; treatment of headaches (n = 2) 20,21 ; weight loss (n = 2) 22,23 ; patients with urinary tract symptoms (n = 1) 24 and in healthy subjects (n = 1) 25 . Caffeine consumption was discouraged in three studies 10,11,21 , and subjects using diuretics were excluded from three studies 11,13,24 , while in one study, the use of diuretics was an inclusion criteria.…”

“…24 Self-report through fluid intake diaries was also utilized, ranging from 1 to 7 days. 20,21,25 Eight out of the 16 studies were randomised controlled trials (RCT), 13,14,16,[20][21][22][23][24] while the others were non-randomised and/or non-controlled trials.…”