Effect of alkalized urine on renal calculi in patients with gout: a protocol for a placebo-controlled, double-blinded randomized controlled trial

Jia, Ertao; Zhu, Hongjun; Geng, Hongling; Wang, Yadong; Zhong, Li; Liu, Shangwen; Lin, Feng; Zhang, Jianyong

doi:10.1186/s13063-021-05721-8

Cited by 1 publication

(2 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Studies have shown that formation of UA stones is strongly propelled by presence of acidic urine (6,7), and thus can be prevented by promoting the urine pH to alkaline range (8,9). Use of sodium bicarbonate is a common option for urine alkalization in patients with UA calculi, but not justified for regular use in normal individuals as a prevention, considerably due to gastrointestinal disturbance.…”

Section: Introductionmentioning

confidence: 99%

“…Use of sodium bicarbonate is a common option for urine alkalization in patients with UA calculi, but not justified for regular use in normal individuals as a prevention, considerably due to gastrointestinal disturbance. On the other hand, a dietary approach could be more acceptable for this purpose (8,(10)(11)(12)(13). Based on the acid-ash hypothesis, oral use of alkaline water has been attempted to provide more alkaline ions after metabolism.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Baseline urine pH is related to effective urine alkalization by short-term alkaline water supplementation: data from a self-controlled study in healthy Chinese volunteers following a systematic review and meta-analysis of literature

Zhang¹,

Deng²,

Deng³

et al. 2022

Transl Androl Urol

View full text Add to dashboard Cite

Background: The outcomes of urine alkalization with alkaline water supplementation vary greatly across studies and therefore remain inconclusive, probably arising from differences in study design, ethnic group, and source of alkaline water, which needs further clarification. With a systematic review of literature, followed by an empirical observation among healthy Chinese volunteers, we aimed to investigate the outcomes of urine alkalization with alkaline water vs. daily drinking water, and whether these outcomes are intersected by certain factors such as gender and body mass index (BMI).Methods: We conducted a literature search of related studies on alkaline water supplementation and urine pH using the PubMed, Embase, Medline and Cochrane Library databases. The publication bias was assessed with inverted funnel plotting. Chi-square-based Q-test and I 2 -statistic test were used to examine the data heterogeneity. The studies were evaluated for quality using the Cochrane risk of bias tool or Newcastle-Ottawa Scale (NOS). The meta-analysis was followed by a study in healthy volunteers. As per protocol, all subjects remained on regular drinking water for one week and were switched to alkaline water for the next week. Urine pH was measured thrice daily and averaged. The mean urine pH values in the first and second weeks were compared for all subjects. Alkalization gains in urine pH (AGU-pH) was computed to determine the outcome of alkaline water supplementation in relation to baseline urine pH.Results: Our systematic review of literature yielded limited data about the effect of alkaline water on urine pH. Despite an increase in urine pH after supplementation of alkaline water as indicated by the randomeffect model, a high heterogeneity across the included studies (I 2 =94%, P<0.001) precluded a robust determination. In our volunteer study, alkaline water led to elevation of urine pH from baseline in 84.9% of all subjects or by BMI stratification. Effective urine alkalization was noted in males but not in females.Subjects who presented effective urine alkalization had significantly lower baseline urine pH compared with those who did not (5.94±0.27 vs. 6.22±0.22, P=0.0016). The negative correlation between AGU-pH and baseline urine pH (r=−0.236, P=0.044) and receiver operating curve (ROC) analysis suggested that subjects with more "acidic" urine, particularly those with a baseline urine pH ≤6.0 (maximum Youden index =1.548, cut-off =5.977), could show more pronounced outcome of urine alkalization from oral alkaline water.Conclusions: Our meta-analysis and human subjects study revealed that alkaline water supplementation may be useful for urine alkalization, particularly in individuals with a lower urine pH. The outcomes seem not significantly pronounced in females, although more efforts warranted for validation. Short-term use of alkaline water is well-tolerated and not associated with over-alkalization of the urine.

show abstract