An Observational Study to Assess Clinical, Molecular and Imaging Biomarkers in Spinal and Bulbar Muscular Atrophy (SBMA)
Background: SBMA is an inherited chronic disease. It affects males in mid to late adulthood. It causes slowly progressive weakness of muscles and hand tremors. Researchers want to learn more about the effects of SBMA.
Objective: To identify measurements that change over time in SBMA, including tests of muscle strength and function, as well as measurements of muscle and fat size.
Eligibility: Men over the age of 18 both with and without a history of SBMA.
Design: Participants will have a medical history, physical exam, and blood and urine tests. They will have neuromuscular ultrasound. They will have a lumbar puncture to obtain spinal fluid. For this, a needle will be inserted into the spinal canal in the lower back. Participants will have muscle strength and function tests. These tests may include pushing, pulling, rising from a chair and sitting back down, and/or walking. During these tests, they may wear an accelerometer (activity tracker) on their wrist. Participants will get an activity tracker to wear on their wrist for 10 days at home every 3 months. Participants with SBMA will also have lower limb magnetic resonance imaging (MRI) and optional whole-body MRI. They will have lung function tests. They will have speech and swallow tests. They will complete questionnaires. They may have optional body scans to measure bone density and lean body mass. They may have optional muscle biopsies. For biopsies, a needle will be used to take a small piece of muscle from the leg. Participants with SBMA will have 5 study visits over 2 years (every 6 months). Participants without SBMA will have 1 study visit.
∙ Some restrictions are placed on participation in the study because we aim to identify disease biomarkers specific to those with early to intermediate stages of disease who would be potential candidates for future therapeutic studies.
∙ In order to be eligible to participate in the SBMA cohort, an individual must meet all of the following criteria:
• Stated willingness to comply with all study procedures and availability for the duration of the study
• Male, above the age of 18 years
• Genetically confirmed SBMA
• Ability of subject to understand and the willingness to sign a written informed consent document
• Ability of subject to travel to the NIH Clinical Center.
∙ Note: an SBMA patient who meets both of the additional following criteria will be offered an optional whole body MRI at subsequent follow-up visits:
• Spinal bulbar muscular atrophy functional rating of \< 50 (and \> 35).
• On initial whole body MRI, subject has evidence of muscle fat replacement such that the total volume of disease affected muscles (i.e., muscles with at least 10% muscle fat infiltration and no more than 50% muscle fat fraction) is at least:
‣ 500ml if only 1 muscle is eligible or
⁃ 250ml if more than one muscle meets the criteria
∙ In order to be eligible to participate in this study in the Healthy Control cohort, an individual must meet all of the following criteria:
• Stated willingness to comply with all study procedures and availability to travel to the NIH for the duration of the study
• Male, above the age of 18 years
• No history of SBMA or other neuromuscular disorder
• No history of facial palsy
• Ability of subject to understand and the willingness to sign a written informed consent document
• Ability of subject to travel to the NIH Clinical Center.