The impact of dietary salt intake and kidney disease on aldosterone regulatio

Not Applicable

Completed

• Conditions: Hypertension in chronic kidney disease (CKD); Urological and Genital Diseases

• Registration Number: ISRCTN25169606
• Lead Sponsor: HS Greater Glasgow and Clyde (UK)

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2014-01-10
• Study Completion: 2015-02-18
• Last Update Posted: 6 July 2020

Recruitment & Eligibility

• Status: Completed
• Sex: All
• Target Recruitment: 48

Inclusion Criteria

1. Individuals aged between 18 and 80 years
2. Individuals with capacity
3. Renal group:
3.1 Patients with CKD who attend the Western Infirmary renal unit and its satellite units CKD stage 3 and CKD stage 4 [decline in glomerular filtration rate (GFR) <5ml/min in preceding 6 months]
3.2 Proteinuric [polymerase chain reaction (PCR) =100mg/mmol] and non proteinuric (PCR <50mg/mmol) patients will be included
3.3 Patients' blood pressure (BP) should be controlled <160/90 mmHg (where applicable patients should be on a stable dose of antihypertensive for four weeks prior to consent for study)
4. Hypertensive group:
4.1 Patients who attend the hypertension clinic at Western Infirmary Glasgow (WIG) or Glasgow Royal Infirmary (GRI)
4.2 Patients' BP should be controlled <160/90 mmHg (where applicable patients should be on a stable dose of antihypertensive for four weeks prior to consent for study)
4.3 No significant proteinuria (PCR <20 mg/mmol)

Exclusion Criteria

1. Individuals unable to give informed consent
2. Diabetes mellitus (possibility of type 4 renal tubular acidosis ? hyporeninaemic hypoaldosteronism)
3. Patients with nephrotic range proteinuria (PCR =300 mg/mmol)
4. Patients on aldosterone antagonist or direct renin inhibitor
5. Individuals pregnant or breast feeding
6. Patients with a history of Conn?s syndrome, Cushing?s disease or Addison?s disease
7. Patients who require maintenance corticosteroids or patients who have had corticosteroid treatment within 3 months prior to study commencing
8. Renal group - patients with progressive (decline in eGFR of >5 ml/min) renal disease in the six months leading up to study start date

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Difference in urinary aldosterone (THALDO) excretion after dietary salt loading between the three groups of patients (CKD, hypertension and control) will be measured from urine samples using gas chromatography-mass spectrometry (GC-MS)

Secondary Outcome Measures

Name	Time	Method
<br> 1. Difference in serum aldosterone levels in response to acute salt loading (modified saline suppression test) at baseline between the three groups of patients.<br> 2. Difference in response to angiotensin II stimulation test (serum aldosterone measurements) between the groups in the low and high salt environment. This test will be carried out at study visit number 2 and study visit number 3.<br> 3. Influence of dietary salt intake on level of muscle sympathetic nerve activity (MSNA). An intraneural recording of MSNA will be made using a tungsten microelectrode after dietary salt loading and dietary salt reduction. This will be carried out at study visit number 2 and study visit number 3 before the angiotensin II stimulation test.<br>