The Effect of Correction of Metabolic Acidosis in CKD on Intrarenal RAS Activity

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02896309

Acronym

BIC

Enrollment

Registered

2016-09-12

Start date

2016-09-30

Completion date

2018-12-27

Last updated

2019-06-20

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Chronic Kidney Disease

Brief summary

This study evaluates the effect of oral sodium bicarbonate treatment on the intrarenal renin-angiotensin-system in adult patients with a metabolic acidosis and chronic kidney disease. This treatment is compared to sodium chloride treatment, which serves as control for increased sodium-intake and no treatment, which serves as time-control.

Detailed description

In chronic kidney disease (CKD), as glomerular filtration rate decreases, excretion of hydrogen ions fails, leading to progressive metabolic acidosis (arterial pH \< 7.35 and a serum bicarbonate concentration \< 22 meq/L). Metabolic acidosis enhances further progression of CKD. It is known that the intrarenal renin-angiotensin system (RAS) is stimulated during metabolic acidosis, but it's specific role in the renal response on changes in the acid-base balance is unknown. Correction of metabolic acidosis by administration of bicarbonate is a common intervention in patients with metabolic acidosis due to chronic kidney disease. It is proven to slow down progression of CKD. There is no knowledge on the effect this therapy has on the intrarenal RAS. Since acidosis does not change serum renin levels, and bicarbonate therapy has no effect on blood pressure, it seems to have no effect on the systemic RAS. The investigators hypothesize that bicarbonate therapy diminishes intrarenal RAS activity without affecting the systemic RAS.

Interventions

DIETARY_SUPPLEMENTSodium bicarbonate

DIETARY_SUPPLEMENTSodium chloride

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to 100 Years

Healthy volunteers

Inclusion criteria

* male or female adult (≥18 years) * chronic kidney disease stage 4, i.e. estimated glomerular filtration rate (MDRD) 15-30 ml/min * plasma bicarbonate concentration of 15-24 meq/L

Exclusion criteria

* bicarbonate level \>24 meq/L or \<15 meq/L, the latter because in that case it seems highly recommended to start sodium bicarbonate suppletion and not to postpone this * sodium bicarbonate use in the 1 month preceding the study * heart failure * liver cirrhosis * blood pressure \>140/90 mmHg despite the use of 3 different antihypertensives * a kidney transplant in situ * a history of nonadherence to medication * use of calcineurin inhibitors (these immunosuppressive drugs are known to induce metabolic acidosis and influence electrolytes and acid-base balance)

Design outcomes

Primary

Measure	Time frame
Urinary renin concentration	4 weeks

Countries

Netherlands

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026