The effect of dietary counselling in reducing sodium consumption among hypercalciuric stone formers and its impact on metabolic risk factors

Author(s): Fernanda Berto, Jennifer Bjazevic, Abdulaziz Alathel, Enad Alsolami, Nabil Sultan, Hassan Razvi

Introduction: Elevated urinary sodium from excessive dietary consumption may lead to hypercalciuria and increase urinary stone risk. Our study aimed to assess the impact of targeted dietary counseling on normalizing urinary sodium levels in hypercalciuric stone patients.

Methods: A retrospective analysis of a prospectively collected metabolic stone clinic database was performed. Patients with hypercalciuria and elevated urine sodium on 24-hour urine collection were counselled by the attending nephrologist, urologist or a registered dietician to limit their dietary sodium to < 2g/day intake. Repeat metabolic testing was performed at least 6 months later. Logistic regression was used to determine correlations between elevated urinary calcium and sodium to other urinary abnormalities, and to evaluate the effect of normalizing urinary sodium on urinary parameters.

Results: Metabolic evaluations from 1184 patients were analyzed. Ninety-eight patients with concomitant hypercalciuria and hypernatriuria were predominantly male (67.3%) and had a higher median body mass index than the entire cohort. The presence of elevated urinary sodium was associated with hyperuricosuria (p<0.001) and hyperphosphaturia (p < 0.001). In follow-up, 59.4% corrected their urinary sodium, and 43.8% also corrected their urinary calcium. Patients who corrected their urinary sodium were also more likely to have normal urinary values for volume (p = 0.045), oxalate (p = 0.004), and urate (p = 0.008).

Conclusions: Targeted dietary counseling can be associated with normalizing both elevated urinary sodium and calcium levels in stone patients and may reduce the need for pharmacotherapy for the treatment of hypercalciuria.