Fast Five Quiz: Spinal Muscular Atrophy in Adults

Stephen L. Nelson, Jr, MD, PhD


February 01, 2021

In many ways, the symptoms of SMA type 4 (adult-onset SMA) mimic those of SMA type 3. For example, the disease course is largely mild, and most patients will have a normal life expectancy.

Disease onset in most patients with SMA type 4 occurs in the third decade of life. There may be a gradual decline in muscle strength and motor function, although this is highly variable among patients and is typically less severe in adult-onset disease than other phenotypes.

Learn more details about SMA in adults.


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