The Effect of Renin Inhibition on Nerve Function in Diabetes

Not Applicable

Completed

Conditions: Diabetes

Interventions: Drug: Aliskiren
Other: Placebo

Registration Number: NCT00935064

Lead Sponsor: Christiana Care Health Services

Brief Summary: This study will assess the effect of direct renin inhibition on nerve function in persons with diabetes using a double-blind, placebo-controlled randomized trial involving two treatment arms (i.e., \[1\] 30 participants enrolled and randomized to 300 mg of Aliskiren; \[2\] 30 participants enrolled and randomized to placebo).

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 60

Inclusion Criteria

Individuals >18 years old with type 1 or type 2 diabetes mellitus.

Exclusion Criteria

Individuals currently taking the maximum dose of an ACE inhibitor or an ARB.
Individuals with a history of a MI, percutaneous coronary interventions, coronary artery bypass graft (CABG) surgery, acute coronary syndromes, recent/on going atrial fibrillation, frequent atrial arrhythmias, frequent ventricular arrhythmias, or acute myocardial ischemia changes.
Individuals whose treatment dosage changes 2 months prior to the study for antihypertensive and antidiabetes medications, and the following medications that may affect the ANS: anti-tuberculosis drugs, nitrofurantoin, metronidazole, chloramphenicol, perhexiline maleate, amiodarone, clofibrate, tricyclic antidepressants, phenytoin, barbiturates, neuroleptic, antiparkinsonism drugs, and nitrated drugs.
Pregnant or lactating females.
Individuals with impaired renal function (i.e., creatinine >1.5 mg/dl), a history of dialysis, nephritic syndrome or renovascular hypertension.
Individuals with potassium levels within 0.5 mmol/L of the upper limit of normal (i.e., hyperkalemia).

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Aliskiren	Placebo	Pill, 300 mg, once daily, for 6 weeks
Placebo	Placebo	-
Aliskiren	Aliskiren	Pill, 300 mg, once daily, for 6 weeks

Primary Outcome Measures

Name	Time	Method
Systolic Blood Pressure Before and After Treatment	baseline and 6 weeks	Systolic blood pressure at baseline and follow-up
Diastolic Blood Pressure Before and After Treatment	baseline and 6 weeks	Diastolic blood pressure at baseline and follow-up.
Serum Renin Level Before and After Treatment	baseline and 6 weeks	Serum renin level at baseline and follow-up
Expiration/Inspiration Ratio Before and After Treatment	baseline and 6 weeks	Expiration/inspiration ratio at baseline and follow-up. There are several different assessment modalities used for the determination of cardiovascular autonomic function (i.e. HRV). One widely used clinical method for assessing HRV is RR-variation during deep breathing. RR-variation is a measure of the change in heart rate resulting from the variation in intrathoracic pressure due to respiration. It is predominantly a function of parasympathetic activity. In this study, RR-variation during deep breathing, performed for 6 min, was measured by vector analysis \[i.e. mean circular resultant (MCR)\] and by the expiration/inspiration (E/I) ratio of the first six breath cycles.
Mean Circular Resultant Before and After Treatment	baseline and 6 weeks	Mean circular resultant at baseline and follow-up. There are several different assessment modalities used for the determination of cardiovascular autonomic function (i.e. HRV). One widely used clinical method for assessing HRV is RR-variation during deep breathing. RR-variation is a measure of the change in heart rate resulting from the variation in intrathoracic pressure due to respiration. It is predominantly a function of parasympathetic activity. In this study, RR-variation during deep breathing, performed for 6 min, was measured by vector analysis \[i.e. mean circular resultant (MCR)\] and by the expiration/inspiration (E/I) ratio of the first six breath cycles. With regard to the MCR, the length of the vector mean is proportional to the degree of HRV. Weinberg and Pfeifer first introduced the assessment of HRV via determination of the MCR in a paper in Biometrics 1984:40:855-861. Low HRV is considered to be less favorable.