Effect of Renin-angiotensin System Blockers on Glomerular Filtration Rate in Patients With Hypertension, Type 2 Diabetes With Normoalbuminuria (eGFR)

This study is ongoing, but not recruiting participants.
Sponsor:
Information provided by (Responsible Party):
Hospital Authority, Hong Kong
ClinicalTrials.gov Identifier:
NCT01500590
First received: December 23, 2011
Last updated: October 22, 2013
Last verified: October 2013
  Purpose

Diabetes is the leading cause of chronic kidney disease in developed countries. About 30-40% of patients with type 1 and type 2 diabetes mellitus will develop diabetic nephropathy. Microalbuminuria is often used as an early predictor of diabetic nephropathy. Many studies already demonstrated the renoprotective effect of Renin-angiotensin-system (RAS) blockers in patients with varying degree of albuminuria, few studies focus on studying the decline in glomerular filtration rate (GFR) among patients with normoalbuminuria. However a substantial number of diabetic patients exist with sub-normal GFR without microalbumin excretion. From literature, DM will have faster decline in GFR but the investigators do not know whether such decline can be slowed down by the use of RAS blockers as compared with other anti-hypertensive drugs. This Study investigate the effect of early treatment with RAS blockers on the decline rate of GFR in diabetic patients with normoalbuminuria.


Condition Intervention Phase
Diabetes
Hypertensive Disease
Drug: Renin-angiotensin system blockers
Drug: non-renin angiotensin system blockers
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Phase IV, Effect of Rennin-Angiotensin System Blockers on Glomerular Filtration Rate in Patients With Hypertension, Type 2 Diabetes With Normoalbuminuria--- A Randomized Controlled Trial

Resource links provided by NLM:


Further study details as provided by Hospital Authority, Hong Kong:

Primary Outcome Measures:
  • change of estimated GFR calculated by MDRD equation and onset of microalbuminuria [ Time Frame: every 3 months ] [ Designated as safety issue: No ]

    DM patients assigned to have RAS blockers have slower decline in GFR and delay in onset of microalbuminuria compared with those using other anti-hypertensive drugs. We measure the value of eGFR at baseline and every 6 months period in both control group and intervention group. The eGFR is calculated by MDRD equation. GFR = 186 x {serum creatinine (umol/l) /88.4}-1.154 x (age) -0.203 x ( 0.742 if female)

    We than calculate the difference of eGFR value every 6 month from the baseline. We would like to compare this difference in both groups.



Estimated Enrollment: 1400
Study Start Date: November 2011
Estimated Study Completion Date: August 2017
Estimated Primary Completion Date: August 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: renin-angiotensin system blockers
Those eligible patients will be randomized into 2 groups. One group use renin-angiotensin systems (RAS) blockers to control their blood pressure, the other group will use other types of anti-hypertensive agents other than RAS blockers
Drug: Renin-angiotensin system blockers
lisinopril 2.5mg to 20mg once daily if patient experience cough, we will use irbesartan 150 mg to 300mg once daily
Other Names:
  • zestril
  • aprovel
Active Comparator: non-renin angiotensive system blockers Drug: non-renin angiotensin system blockers
amlodipine 2.5 to 10 mg once daily nifedipine retard 20mg to 40mg twice daily indapamide 2.5mg once daily metoprolol 25mg to 100mg daily methyldopa 125 mg to 500mg twice daily
Other Names:
  • norvasc
  • adalat retard
  • natrilix
  • betaloc
  • aldomet

Detailed Description:

Renal excretory function, represented by GFR, deteriorates with age. After age 20-30 years, GFR declines by 1ml/min per year. This age related loss of renal function is proportional to blood pressure and glycemic level, and the rate of decline can accelerate up to 10-12 ml/min per year in poor BP and glycemia control.(1) Such rate of deterioration may lead to end-stage renal failure and the need for dialysis or transplantation.

Chronic kidney disease (CKD) is defined as either presence of kidney damage or GFR< 60 ml/min/1.73 m2 for more than 3 months. Kidney damage is defined as pathological abnormalities or markers of damage, including abnormalities in blood or urine tests or imaging studies. Microalbuminuria is often an early and sensitive marker of kidney damage in many types of chronic kidney disease. Among patients with chronic kidney disease, the stage is divided into stage 1-5 by the level of GFR, with higher stages representing lower GFR levels.(2) Renin-Angiotensin System ( RAS) is an enzymatic cascade in which angiotensinogen is cleaved by renin to form angiotensin I, which in turn, is converted by angiotensin converting enzyme (ACE) to form angiotensin II. Angiotensin II produces renal vasoconstriction, so blocking the RAS is shown to be a useful approach to reduce the renovascular risk. Among the RAS blocking agents, angiotensin converting enzyme inhibitor (ACEI) and angiotensin receptor blockers (ARB) are most commonly used in clinical practice.

Many studies already demonstrated the renoprotective effect of ACEI and ARB. These studies include MicroHOPE study(3), IRMA(4), IDNT(5), RENNAL(6) with subjects having varying degree of albuminuria. With compelling benefit of RAS blockers in diabetic patients with albuminuria, current guideline from American diabetic Association (ADA) recommend the use of ACEI and ARB to delay the progression of renal disease in diabetic nephropathy.(7) According to the National Kidney Foundation guideline, the workgroup recommend hypertensive patients with diabetes and CKD stage 1-4 should be treated with an ACEI or ARB, usually in combination with a diuretic.(8) For patients with suboptimal GFR (>= 60 ) without evidence of kidney damage like microalbuminuria, they are not considered as having CKD. There is lack of consensus on the selection of anti-hypertensive medication in this group of patients.

For subjects having normoalbuminuria, BENEDICT study demonstrates the delay in onset of microalbuminuria with the use of either trandolapril alone or trandolapril plus verapamil.(9) In ADVANCE trial, treatment with fixed combination of perindopril and indapamide reduced total renal event by 21%, defined as having new or worsening nephropathy or the development of new microalbuminuria.(10) However these studies mainly focus on using urinary albumin excretion as outcome measures. They seldom took the value of GFR into account.

However studies have found that significant decline in GFR in the absence of increase urine albumin excretion exists in a substantial percentage of adults with diabetes.(11) Decline in GFR should have diagnostic and prognostic value equivalent to urinary albumin excretion. However from literature, we cannot found the effect of RAS blockers on the decline in GFR. We therefore would like to carry out this study to investigate whether RAS blockers can delay the progress of renal disease, with particular attention to the value of GFR, in patients with GFR>=60 but without microalbuminuria.

  Eligibility

Ages Eligible for Study:   35 Years to 75 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion criteria:

  1. age >=35 - 75 years old who is capable to give consent
  2. Chinese
  3. Type 2 DM diagnosed according to ADA guideline
  4. Estimated GFR (eGFR) >=60 - 89 ml/min/1.73m2 calculated by the abbreviated 4 variable Modification of Diet in Renal Disease (MDRD) study equation and no other identified causes of renal insufficiency.
  5. normoalbuminuria determined by urine albumin to creatinine ratio <2.5 mg/mmol for men or < 3.5 mg/mmol for women in first morning void urine sample.

Exclusion criteria:

  1. patients currently on ACEI or ARB as their anti-hypertensive medication
  2. Pregnancy
  3. Type 1 diabetes
  4. Non-diabetic renal disease including renal artery stenosis
  5. secondary hypertension
  6. History of heart failure or myocardial infarction
  7. specific indication for or contraindication to use ACEI or ARB
  8. History of allergy to ACEI or ARB
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01500590

Locations
China
Hospital Authority, HKEC, FM&PHC
Hong Kong, China
Sponsors and Collaborators
Hospital Authority, Hong Kong
Investigators
Principal Investigator: Wai Sing, Daniel CHU, M.B.,B.S. Hospital Authority, Hong Kong
  More Information

No publications provided

Responsible Party: Hospital Authority, Hong Kong
ClinicalTrials.gov Identifier: NCT01500590     History of Changes
Other Study ID Numbers: 001
Study First Received: December 23, 2011
Last Updated: October 22, 2013
Health Authority: Hong Kong: Department of Health
Hong Kong: Ethics Committee

Keywords provided by Hospital Authority, Hong Kong:
Diabetes
hypertensive
without albuminuria

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 2
Hypertension
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Vascular Diseases
Cardiovascular Diseases

ClinicalTrials.gov processed this record on April 17, 2014