Clinical trial NCT00438321: Effect of Increasing Testosterone on Insulin Sensitivity in Men With the Metabolic Syndrome
Official title: Effect of Increasing Testosterone on Insulin Sensitivity in Men With the Metabolic Syndrome
Study type: INTERVENTIONAL
Overall status: TERMINATED
Phase: PHASE1
Conditions: Metabolic Syndrome
Keywords: Overweight
obesity
testosterone
diabetes
metabolic syndrome
aging
Lead sponsor: Massachusetts General Hospital
Sponsor class: OTHER
Collaborators: name: National Institutes of Health (NIH)
name: American Diabetes Association
First posted: 2007-02-22
Enrollment: 66
Sex: MALE
Minimum age (years): 50
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The purpose of the study is to examine the effect of testosterone treatment on insulin in men with the metabolic syndrome with testosterone levels at or below the lower end of the normal range.

Detailed description: The metabolic syndrome is a medical condition defined by high cholesterol levels, high blood pressure, increased abdominal obesity (gain in fat around the region of the stomach), and insulin resistance. Insulin is the hormone that your body produces to decrease the levels of sugar in your blood. A person that is insulin resistant needs more insulin to decrease blood sugar levels than a normal person does. Insulin resistance can lead to type 2 diabetes, which is one of the most common illnesses in the United States.

There is evidence pointing to a relationship between insulin and testosterone in men (testosterone is the male sex hormone that is produced in the testes). As men get older their testosterone levels decrease while their weight and insulin resistance tends to increase. The purpose of this research study is to learn more about the details of the relationship between insulin and testosterone. A clearer understanding of this relationship can have an important impact on public health due to the high rate of health problems associated with diabetes, obesity, and heart disease.

We are looking for men between the ages of 50-75 with the metabolic syndrome to participate in this research study. Participation in this study involves taking medication and/or placebo (a placebo looks exactly like the study medication but contains no active drug), blood tests, muscle biopsies, and imaging scans. This study involves outpatient visits. Subjects are paid up to $500 for completing the study.

Eligibility criteria: Inclusion Criteria:

Stable weight for previous three months (no weight change greater than or equal to +/-10 lbs)

Exclusion Criteria:

* No new diagnosis of type 2 diabetes or on oral hypoglycemic agents
* No history of testicular disorders
* No history of bleeding disorders (i.e. Pulmonary Embolism, Deep Vein Thrombosis, stroke, hypercoagulable syndrome)
* No history of prostate cancer
* No previous diagnosis of osteoporosis
* No history of sleep apnea (subjects will also be excluded if at their baseline assessment they admit to heavy snoring, restless sleep, and/or excessive daytime somnolence)
* No symptoms of urinary outflow obstruction or medications for prostate disease
* No illicit drug use or heavy alcohol use (\>4 drinks/day)

Primary outcomes:
measure: Insulin sensitivity
timeFrame: 3 months
Secondary outcomes:
measure: Resting energy expenditure
timeFrame: 3 months
measure: Lipid profile
timeFrame: 3 months
measure: Body composition
timeFrame: 3 months
measure: Intramyocellular fat
timeFrame: 3 months
Other outcomes:
Locations:
city: Boston
country: United States
facility: Massachusetts General Hospital
state: Massachusetts
Study officials:
affiliation: Massachusetts General Hospital
name: Frances J Hayes, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Pitteloud N, Hardin M, Dwyer AA, Valassi E, Yialamas M, Elahi D, Hayes FJ. Increasing insulin resistance is associated with a decrease in Leydig cell testosterone secretion in men. J Clin Endocrinol Metab. 2005 May;90(5):2636-41. doi: 10.1210/jc.2004-2190. Epub 2005 Feb 15.
citation: Pitteloud N, Mootha VK, Dwyer AA, Hardin M, Lee H, Eriksson KF, Tripathy D, Yialamas M, Groop L, Elahi D, Hayes FJ. Relationship between testosterone levels, insulin sensitivity, and mitochondrial function in men. Diabetes Care. 2005 Jul;28(7):1636-42. doi: 10.2337/diacare.28.7.1636.