The overall goal of this study is to develop a new and practical way to prevent the development of Hypoglycemia Associated Autonomic Failure (HAAF), which is unawareness of hypoglycemia (low blood sugar) in individuals with diabetes. Previous studies suggest that two medications, naloxone and diazoxide, may increase the body's ability to respond to episodes of low blood sugar and prevent the development of HAAF (or hypoglycemia unawareness). Only healthy subjects are being recruited for this study. The study has three distinct phases. In the first phase, healthy, non-diabetic individuals who are susceptible to developing HAAF are identified. Only these individuals will be studied in the second and third phases. The second phase of this study evaluates the effect of using a naloxone nasal spray versus a placebo nasal spray in improving the body's response to episodes of low blood sugar and in preventing the development of HAAF. The third phase of this study evaluates the effect of using naloxone nasal spray and diazoxide in combination, compared to naloxone nasal spray plus a placebo (for diazoxide) or diazoxide plus a placebo (for naloxone) in improving the body's response to episodes of low blood sugar and in preventing the development of HAAF.
Type I diabetes affects the body's ability to respond to low blood sugar (hypoglycemia). Repeated episodes of hypoglycemia may affect an individual's autonomic system, and leads to Hypoglycemia Associated Autonomic Failure (HAAF) in around two-thirds of individuals. This study is looking at healthy, non-diabetic individuals who are susceptible to developing HAAF and their response to either naloxone nasal spray alone or in combination with diazoxide in improving their body's ability to respond to episodes of low blood sugar, and in preventing the development of HAAF. The body's response to episodes of hypoglycemia is measured using a procedure called a hypoglycemic clamp. Each phase of this study involves three clamp procedures over a period of 2 days. During the clamp procedures, glucose (a sugar) and insulin (a hormone produced in the pancreas that regulates the amount of glucose in the blood) are infused with an intravenous catheter, and blood samples are collected periodically throughout the procedure to measure blood sugar levels and the levels of several hormones, including epinephrine, that are found in the body and are related to glucose metabolism. The rates of endogenous glucose production (a measure of the body's production of sugar) will be measured. Additionally, the level of awareness of hypoglycemia symptoms will be monitored using a standardized questionnaire. Both hypoglycemia and stress activate the body's opioid system. Recently published data has shown that blocking opioid receptors with naloxone may increase the body's ability to respond to hypoglycemia.The body's response to hypoglycemia affects many systems, and acting on several of these systems may help the body to respond more effectively to episodes of low blood sugar, and to prevent the development of HAAF. Studies have shown that potassium channels in the hypothalamus, a part of the brain, have an important role in detecting hypoglycemia. Diazoxide activates potassium channels in the cells of the brain that respond to changes in sugar (glucose) that occur in the body, and may also reduce the development of hypoglycemia associated autonomic failure. Additionally, certain glucose-responsive cells in the brain have opioid receptors that are combined with potassium channels which may respond to both diazoxide and naloxone which may work together to more effectively increase the body's ability to respond to episodes of low blood sugar and prevent HAAF. UPDATE: This study was terminated early and only the second phase (Aim 2) of the study above was conducted. This phase was designed to assess the effect of opioid receptor antagonist - intranasal naloxone - as compared to matched placebo on experimentally induced HAAF in healthy, nondiabetic volunteers.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
DOUBLE
Enrollment
4
Albert Einstein College of Medicine
The Bronx, New York, United States
Comparison of Peak Epinephrine Levels Between First and Third Hypoglycemic Clamp Episodes
Peak epinephrine levels during the first (during Day 1) and third (During Day 2) hypoglycemic clamp episodes were compared. Blood samples were taken every 15 minutes throughout clamp procedures and analyzed using high performance liquid chromatography to measure epinephrine levels. Peak epinephrine levels during the course of the three clamp procedures over the two days were identified for each participant. Results are summarized and reported by study arm using basic descriptive statistics. A reduction of \>20% in the average peak epinephrine levels between first and third hypoglycemic clamp episodes will be considered to define HAAF.
Time frame: Obtained every 15 minutes during the first and third 2-hour hypoglycemic episodes (on Day 1 and Day 2), crossover visits up to approximately 6 months apart
Endogenous Glucose Production (EGP)
EGP, a measure of the body's production of sugar, was assessed by determining the Glucose Infusion Rate (GIR), an indirect measure of endogenous glucose production, during the first and third hypoglycemic clamp episodes. GIR is reported in cubic centimeters/minute (cc/min) and results are summarized and reported by study arm using basic descriptive statistics.
Time frame: Obtained every 15 minutes during the 1st and 3rd 2-hour hypoglycemic episodes (on Day 1 and Day 2), crossover visits up to ~6 months apart. Data from the five timepoints over the final hour of the 1st and 3rd clamp episodes were averaged/reported.
Symptoms of Low Blood Sugar
Symptoms of low blood sugar were assessed during steady state (the last 30 minutes) using the Edinburgh Hypoglycemia Symptom Scale (EHSS). The EHSS questionnaire is comprised 11 key symptoms (sweating, palpitations, shaking, hunger, confusion, drowsiness, odd behavior, speech difficulty, incoordination, nausea, and headache) and asked participants to evaluate these symptoms using an 8-point Likert scale ranging from 0 ("Not at all") to 7 ("Very severe"), for an overall possible range of 0-77 for each patient, such that higher scores are associated with more intense hypoglycemic symptoms. EHSS scores were summed and averaged and reported by study arm using basic descriptive statistics.
Time frame: Obtained every 15 minutes during the first and third 2-hour hypoglycemic episodes (on Day 1 and Day 2), crossover visits up to approximately 6 months apart
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.