Clinical Trial: A Randomized Double-Blind Study Testing the Effects of Pregabalin on Diabetic Neuropathy

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: A Randomized, Double-Blind, Placebo-Controlled, Single Center Study Designed to Assess the Effects of Pregabalin on Change in Patients With Diabetic Neuropathy

Brief Summary: This study is designed to examine how pregabalin affects parameters of autonomic nerve regulation in correlation with change in pain, anxiety, and depressive symptoms in patients with diabetic neuropathy.

Detailed Summary: This study is designed to primarily examine how pregabalin affects the autonomic nerve or sympathetic-parasympathetic regulation in patients with diabetic neuropathy and its relationship to neuropathic pain. The goals of this study include (1) assessing the change of parameters of autonomic nerve function such as heart rate variability (HRV), respiratory sinus arrhythmia (RSA), minute ventilation, and changes in objective sleep parameters measured by means of the LifeShirt, upon treatment of pregabalin in comparison to placebo; (2) assessing the symptom change of neuropathic pain upon treatment of pregabalin in comparison to placebo; (3) assessing the change of anxiety symptoms upon treatment of pregabalin in comparison to placebo; (4) assessing the change of depressive symptoms upon treatment of pregabalin in comparison to placebo; (5) assessing the relationship of autonomic nerve function with neuropathic pain at baseline prior to treatment and the correspondences to the study drug; (6) assessing the relationship of autonomic nerve function with anxiety and depressive symptoms at baseline prior to treatment and their correspondences to the study drug; (7) identifying sensitive and reliable parameters of autonomic nerve regulation as predictor(s) of the severity and improvement of neuropathic pain and/or anxiety; and (8) to assess the change in objective sleep parameters (EEG/EOG) by means of the LifeShirt, upon treatment of pregabalin in comparison to placebo
Sponsor: Duke University

Current Primary Outcome:

  • Assessing the Change in Resting Blood Pressure Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy. [ Time Frame: baseline and at end of a 4-week intervention ]
  • Assessing the Change in Heart Rate by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy. [ Time Frame: baseline and at end of a 4-week intervention ]
    The LifeShirt System, developed by VivoMetrics, is a lightweight vest with embedded sensors that continuously collect information on a range of cardiopulmonary parameters. It was used to collect and store the respiratory rate, posture, activity level, QRS complexes, and R-R intervals via a 3-axis accelerometer and a 3-lead, single channel electrocardiogram.
  • Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy. [ Time Frame: baseline and at end of a 4-week intervention ]
    Heart rate variability parameters generated by the frequency domain analysis included: total power (area under the curve) over all frequencies, very low frequency (VLF, 0-0.04 Hz),low frequency (LF, 0.04-0.15 Hz), and high frequency (HF,0.15-0.4 Hz).
  • Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy. [ Time Frame: baseline and at end of a 4-week intervention ]
    Heart Rate Variability parameters generated by the frequency domain analysis included: Low Fre

    Original Primary Outcome: Assessing the change of parameters of autonomic nerve function such as Heart Rate Variability (HRV), Respiratory Sinus Arrhythmia (RSA), minute ventilation, and blood pressure by means of the LifeShirt [ Time Frame: 4 weeks of treatment ]

    Current Secondary Outcome:

    • To Assess the Change of Pain Symptoms Upon Treatment of Pregabalin in Comparison to Placebo. [ Time Frame: baseline and end of 4 week intervention ]
      Pain severity was evaluated using the Visual Analog Scale, the Modified Brief Pain Inventory-Short Form, and the Neuropathy Pain Scale. The Visual Analog Scale was scored within a range of 0-100 with 0=no pain and 100=the worst imaginable pain. The Brief Pain Inventory is made up of two parts: total pain and pain interference. The total pain score is the sum of most, least, average, and now pain scored within a range of 0-10 with 0=no pain and 10=pain as bad as you can imagine. The pain interference score is the sum of affective and activity interference - how pain interfered with general activity, mood, walking ability, normal work, relationships, sleep, and enjoyment of life. It was scored within a range of 0-10 with 0=pain does not interfere and 10=pain completely interferes. The Neuropathy Pain Scale total is the sum of 10 items -cold, sharp, deep, dull, hot, intense, itchy, sensitive, surface, and unpleasant pain scored within a range of 0-10 with 0=no pain and 10=most pain.
    • To Assess the Change of Anxiety Symptoms Upon Treatment of Pregabalin in Comparison to Placebo. [ Time Frame: baseline and at end of a 4-week intervention ]
      Anxiety symptoms were measured using the Spielberger State-Trait Anxiety Inventory Scale (STAI) for symptoms of anxiety. State anxiety: score range, 20-80 (higher score=greater levels of state anxiety). Trait anxiety: score range, 20-80 (higher score=greater levels of trait anxiety).
    • To Assess the Change of Depressive Symptoms Upon Treatment of Pregabalin in Comparison to Placebo. [ Time Frame: baseline and at end of a 4-week intervention ]
      The Beck Depression Inventory Scale measures symptoms of depression, score range, 0-63 (higher score=greater severity of depressive symptoms)
    • To Assess the Change in Disability Scale Upon Treatment of Pregabalin in Comparison to Placebo. [ Time Frame: baseline and at end of a 4-week intervention ]
      The Sheehan Disability Scale was used to evaluate functional impairment in work/school, social and family life, score range, 0-10; the 3 items can be summed into a single dimensional measure of global functional impairment that ranges from 0(unimpaired) to 30 (highly impaired).


    Original Secondary Outcome: Assessing the change of pain symptoms upon treatment of pregabalin in comparison to placebo [ Time Frame: 4 weeks of treatment ]

    Information By: Duke University

    Dates:
    Date Received: December 12, 2007
    Date Started: March 2006
    Date Completion:
    Last Updated: July 11, 2014
    Last Verified: July 2013