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Kennedy disease

Other Names for this Disease
  • Bulbospinal muscular atrophy
  • SBMA
  • Spinal and bulbar muscular atrophy
  • Spinobulbar muscular atrophy
  • X-linked bulbospinal amyotrophy
More Names
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Kennedy disease is a gradually progressive neuromuscular disorder chiefly characterized by wasting of the proximal muscles (those closer to the trunk) and bulbar muscles (those of the face and throat).[1][2] The condition mainly affects males, with onset between the ages of 30 and 60.[1][2] Early signs and symptoms may include tremor, muscle cramps and muscle twitching, followed by progressive muscle weakness and wasting which may manifest in a variety of ways.[1][2] Affected individuals may also have gynecomastia, testicular atrophy (reduction in size or function), and reduced fertility.[2] It is caused by a mutation in the androgen receptor (AR) gene, in which a DNA segment known as a CAG triplet repeat is abnormally expanded.[3] It is inherited in an X-linked recessive manner. Treatment may include physiotherapy and rehabilitation, medications for tremor and muscle cramps, and hormone therapy or surgical treatment of gynecomastia.[1]
Last updated: 9/28/2012


  1. Josef Finsterer. Kennedy disease. Orphanet. July 2011; Accessed 9/28/2012.
  2. Albert La Spada. Spinal and Bulbar Muscular Atrophy. GeneReviews. October 13, 2011; Accessed 9/28/2012.
  3. Spinal and bulbar muscular atrophy. Genetics Home Reference. May 2006; Accessed 9/28/2012.
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  • PubMed is a searchable database of medical literature and lists journal articles that discuss Kennedy disease. Click on the link to view a sample search on this topic.