Urinary pH as a Target in the Management of Lithiasic Patients in Real-World Practice: Monitoring and Nutraceutical Intervention for a Nonlithogenic pH Range

Abstract

Introduction: We assessed the effectiveness of the joint use of a pH meter in combination with dietary supplements in restoring the urinary pH balance of patients with medical history of uric acid or calcium phosphate/calcium oxalate stones in real-world practice. Methods: An interventional, prospective, and open-label study was performed. At baseline visit, patients were assigned to a group according to the type of previous calculus and urinary pH: the alkalinizer group (uric acid stones and/or pH < 5.5) and acidifier group (calcium oxalate stones and/or pH > 6.2) received dietary supplement to increase or decrease, respectively, urinary pH. Patients were examined at baseline and after treatment for 30, 60, and 90 days. Urinary pH, type of therapy, compliance, and self-reported renal colic events were recorded at each visit. Results: The study included 143 patients, 45.5% in the alkalinizer group and 54.5% in the acidifier group, and the mean age was 53.60 years. Both nutraceuticals were significantly effective in normalizing urinary pH (P < 0.00001) at all follow-up visits compared with baseline, with a maximum percentage of patients who achieved nonlithogenic pH (54.9%) at day 60 (P < 0.00001). Analysis of the effect of treatment compliance at 60 days indicated that 71.8% of compliant and 45.9% of noncompliant patients achieved nonlithogenic pH (odds ratio [OR]: 3.03, 95% confidence interval [CI]: 1.29-6.66). A Cox-regression model indicated that nonlithogenic pH at 90 days (hazard ratio [HR]: 0.428, 95% CI: 0.193-0.947) and compliance at 60 days (HR: 0.428, 95% CI: 0.189-0.972) were independently associated with colic complaints-free survival. Conclusions: In patients with medical history of renal lithiasis, monitoring of pH in combination with dietary supplements may be useful in maintaining nonlithogenic pH values, yielding very high ratios of success, especially in compliant patients. Besides this main outcome, a reduction in self-reported colic complaints associated with pH balance was also observed.