Effect of salt intake reduction on nocturia in patients with excessive salt intake

Neurourol Urodyn. 2019 Mar;38(3):927-933. doi: 10.1002/nau.23929. Epub 2019 Feb 1.

Abstract

Aims: To assess the efficacy of salt reduction for improving nocturia in patients with high salt intake.

Methods: Changes in lower urinary symptoms and frequency volume chart by salt intake (men: 8 g/day; women: ≥7 g/day) were analyzed in this prospective study. Patients were instructed to use a brochure for salt intake restriction via interview once every four weeks. The daily salt intake was estimated by using spot urine samples.

Results: Two-hundred twenty-three (69.5%) patients were successful in reducing their daily salt intake (S group), whereas 98 (30.5%) patients failed to reduce their salt intake (F group). In the S group, nocturia improved from 2.3 ± 0.9 to 1.4 ± 1.0, and nocturnal polyuria index (NPi) improved from 30.2 ± 7.5 to 27.7 ± 7.3% (P < 0.001). In the Core Lower Urinary Tract Symptom Score (CLSS) of the S group, Q3 (urgency) improved from 1.0 ± 1.0 to 0.9 ± 1.0 (P = 0.001); Q1 (diurnal frequency) (P < 0.001), and Q2 (nocturia) also improved (P < 0.001). Moreover, the quality of life parameter improved significantly (P < 0.001). The patients in the F group did not have improvements in any symptom during the study period.

Conclusions: Patients with nocturia who also have high salt intake should be advised to reduce their salt intake, as a lifestyle modification. Our results support the importance of randomized clinical trials with larger populations and the appropriate inclusion/exclusion criteria to conclude the clinical usefulness of salt reduction in this patient cohort.

Keywords: lower urinary tract symptoms; nocturia; salt intake reduction; treatment.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Circadian Rhythm
  • Cohort Studies
  • Diet, Sodium-Restricted*
  • Female
  • Humans
  • Lower Urinary Tract Symptoms / diet therapy
  • Male
  • Middle Aged
  • Nocturia / diet therapy*
  • Nocturia / etiology*
  • Prospective Studies
  • Sodium Chloride, Dietary / adverse effects*
  • Treatment Outcome
  • Urination
  • Urodynamics

Substances

  • Sodium Chloride, Dietary