Neurology, Addiction and Psychiatry Conference

SBMA, or Spinal Bulbar Muscular Atrophy, is another name for Kennedy's disease, which is a genetic neurodegenerative disorder characterized by widespread motor neuron loss in the spinal cord and brainstem. The effects of SBMA include progressive weakness, atrophy, and dysfunction of the bulbar leading to severe dysfunction of muscle control, speech, swallowing, and respiration. It results from mutation in the androgen receptor (AR) gene, where there is an abnormal accumulation of the androgen receptor protein in the neurons that progressively damages motor neurons over time. SBMA is an X-linked disorder which means it predominantly affects males, though female carriers may sometimes experience mild symptoms.

Classic features of SBMA include muscle weakness and atrophy in the limbs and bulbar muscles that are tasked with functions such as speech and swallowing. In most cases, symptoms start appearing in adulthood at around 30 to 50 years of age. Initial presentations include a client's impaired ability to walk or maintain balance and fine motor capabilities as well as hand cramping and tremors. Finally, symptoms from the bulbar become so predominant that the disease course is shaped by such symptoms that patients develop significant impairments in speech and swallowing (dysphagia), and significant respiratory complications can occur in the terminal stages.

SBMA is a disease, which occurs due to the expansion of a CAG repeat within the androgen receptor gene leading to toxic gain of function in motor neurons. The genetic mutation is transmitted from father to mother, and most females harboring this genetic mutation are asymptomatic or mildly affected with weakness in muscles.

Genetic testing is confirmed for the diagnosis of SBMA by showing an abnormal mutation within the androgen receptor gene. Early diagnosis allows the development of therapeutic approaches that may, at least temporarily, improve the quality of life for the patient. Though currently, a certain cure is not available, still research strides forward in therapy, moving one step closer to the disease mechanisms: reduction of the receptor's toxicity to the androgen receptor and guaranteeing survival of the motor neurons.

Multi-disciplinary approaches to the management of SBMA: Here, along with this approach, physical therapy, speech therapy, and nutritional support are the components that keep the functionality of muscles in place, and the bulbar symptoms are kept under management. Spasm of muscle cramps can also be medicated upon, and to reduce the activities of the androgen, hormonal therapy may also take place.

Future prospects in new therapies, such as gene therapy, androgen receptor antagonists, and neuroprotective agents, are being researched as possible future treatments which could perhaps slow down the progression of SBMA and lead to better lives for those afflicted by this often debilitating disease.