The Effect of Aliskiren and Losartan on Peritoneal Membrane in Continuous Ambulatory Peritoneal Dialysis Patients

• appearance rate of dialysate CA125 [ Time Frame: the begining, 6 months and 12 months ] [ Designated as safety issue: Yes ]
  Appearance rate of dialysate CA125 refers to anatomical change of peritoneal. It can be calculated by multiplying dialysate CA125 with dialysate volume and deviding by dwell time.
• nutritional status [ Time Frame: at the beginning, 6 months and 12 months ] [ Designated as safety issue: Yes ]
  assess by serum albumin and subjective global assessment
• adverse events [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]
  adverse events of the drugs

• appearance rate of dialysate CA125 [ Time Frame: the begining, 6 months and 12 months ] [ Designated as safety issue: Yes ]
  Appearance rate of dialysate CA125 refers to anatomical change of peritoneal. It's can be calculated by multiplying dialysate CA125 with dialysate volume and deviding by dwell time.
• nutritional status [ Time Frame: at the beginning, 6 months and 12 months ] [ Designated as safety issue: Yes ]
  assess by serum albumin and subjective global assessment
• adverse events [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]
  adverse events of the drugs

This is a prospective, randomized, placebo controlled, multi-center clinical trial to determine whether aliskiren or aliskiren plus losartan or enalapril plus losartan effects on peritoneal membrane transportation.

Detailed description:

Many peritoneal dialysis patients suffer from uremia due to inadequate dialysis or volume overload caused by failure of peritoneal membrane transportation. One of the most important etiologies of peritoneal membrane failure is unavoidable to use high glucose-containing dialysate solution that induces injury to mesothelial cells. Previous data found that injured mesothelial cell produced Angiotensin II inducing peritoneal inflammation and fibrosis. Blockade of the renin-angiotensin system by angiotensin-converting enzyme inhibition or angiotensin receptor antagonism play a major role to slow these effects.

Many trials in animal studies have proved the benefit of angiotensin-converting enzyme inhibition and angiotensin receptor antagonism in preservation of peritoneal membrane but clinical evidences in human are controversy in the past. Recently our data have demonstrated the roles of angiotensin-converting enzyme inhibition and angiotensin receptor antagonism for slowing peritoneal membrane dysfunction in views of anatomy and solute transportation (abstract presentation in American Society of Nephrology 2010). These available data confirmed that renin-angiotensin system blockages were benefit. Nowadays, there is a new class of antihypertensive drug, called direct renin inhibitor . It blocks (pro)renin active site that is the rate- limiting step of renin-angiotensin system. We're interesting in this drug and wonder it can slow the peritoneal membrane dysfunction in continuous ambulatory peritoneal dialysis patients. Therefore, we design a study to show the effect of aliskiren alone or combination with angiotensin receptor antagonism for slowing peritoneal membrane dysfunction in naive continuous ambulatory peritoneal dialysis patients in several hospitals. Our study will be taken in 1 year duration and uses modified peritoneal equilibrium test and dialysate cancer antigen 125 (CA125) as indexes of peritoneal membrane transportations.

• Drug: placebo
  Patients in the control group will administer antihypertensive agents, except angiotensin converting enzyme inhibitors, angiotensin receptor blockers and spironolactone. Dosages are adjusted appropriately to achieve and maintain the target blood pressure of 130/80 mmHg
  Other Name: Control
• Drug: Aliskiren
  Patients with hypertension will take fixed-dose 150 mg aliskiren per day. Antihypertensive agents other than angiotensin converting enzyme inhibitors, angiotensin receptor blocker and spironolactone will be allowed and dosages are adjusted appropriately to achieve and maintain the target blood pressure of 130/80 mmHg
  Other Name: Aliskiren group
• Drug: Aliskiren plus Losartan
  Patients with hypertension will take fixed-dose 150 mg aliskiren + 50 mg losartan per day. Antihypertensive agents other than angiotensin converting enzyme inhibitors, angiotensin receptor blockers and spironolactone will be allowed and dosages are adjusted appropriately to achieve and maintain the target blood pressure of 130/80 mmHg
  Other Name: Aliskiren plus Losartan group
• Drug: Enalapril plus Losartan
  Patients with hypertension will take fixed-dose 20 mg enalapril + 50 mg losartan per day. Antihypertensive agents other than angiotensin converting enzyme inhibitors, angiotensin receptor blockers and spironolactone will be allowed and dosages are adjusted appropriately to achieve and maintain the target blood pressure of 130/80 mmHg
  Other Name: Enalapril plus Losartan group

• Active Comparator: Aliskiren
  Intervention: Drug: Aliskiren
• Active Comparator: Aliskiren plus Losartan
  Intervention: Drug: Aliskiren plus Losartan
• Active Comparator: Enalapril plus Losartan
  Intervention: Drug: Enalapril plus Losartan
• Placebo Comparator: placebo
  Intervention: Drug: placebo

Inclusion Criteria:

1. All patients received continuous ambulatory peritoneal dialysis less than one and a half years
2. Subjects of either sex, more than 20 years old
3. Hypertension
4. Provision of written informed consent by subject or guardian

Exclusion Criteria:

1. No history of taking an angiotensin converting enzyme inhibitor or angiotensin-receptor blockers or aldosterone antagonist for at least 2 month
2. Serum potassium more than 5.5 mEq/L
3. History of renal artery stenosis
4. Peritonitis or volume overload within the preceding 1 month
5. Myocardial infarction within the preceding 6 months or clinically significant valvular disease or any active cardiovascular disease
6. History of malignant hypertension or hypertensive encephalopathy or cerebrovascular accident within the preceding 6 months
7. Any condition that may have precluded a patient from remaining in the study, such as alcohol or drug abuse, chronic liver disease, malignant disease, or psychiatric disorder
8. History of allergy or intolerance to an angiotensin converting enzyme inhibitors or angiotensin receptor blockers
9. Hypotension defined as systolic blood pressure less than 90 mmHg