The symptoms of Kennedy’s Disease (KD), or spinal and bulbar muscular atrophy, are greatly varied due to the broad effects of motor neurons in the body. It is common for the clinical signs and symptoms to be asymmetric with one side of the body more affected than the other.
Symptoms typically present in adulthood between the age of 20 and 50. However, some patients may be diagnosed earlier and some patients do not report symptoms until the age of 70 years. The life expectancy of patients is not greatly altered due to the slow progression of disease.
There are several symptoms related to nervous system that affect individual’s with Kennedys disease, including:
- Altered control of breathing, swallowing and talking (bulbar signs)
- Tremor in hands when in action
- Abnormal contraction of foot muscles in response to stimulus
- Weakness of muscle
- Numbness or loss of sensation
- Decreased or absent reflexed
The muscular symptoms also play a large role in the pathophysiology of Kennedy’s disease and can affect patients greatly. These include:
- Fasciculation or visible small muscle twitching
- Large muscle spasms or cramping
- Postural tremor
- Wasting or reduction of muscle
- Hypertrophy in calf muscles due to frequent cramps.
In addition to the neurological and muscular symptoms, there are various other symptoms that commonly affect patients with Kennedy’s disease. These symptoms include:
- Enlarged breasts
- Hormonal imbalance (androgen deficiency and estrogen excess leading to loss of masculinization)
- Erectile dysfunction and impotence
- Low sperm count
- Testicular changes in size and function
- Elevated serum creatinine kinase
Disease and Symptom Progression
Many patients presenting with Kennedy’s for the first time have a long history of muscle cramping, limb weakness and quickness to fatigue. These initial sign and symptoms can be viewed as normal and individuals may not initially be aware of the progression of disease.
In many cases, it is the bulbar signs that prompt patients to seek medical advice about their symptoms. Difficulty in chewing, swallowing and speaking are seen as abnormal and individuals commonly present in this stage to be diagnosed.
Following these signs, postural tremor and upper extremity tremor usually appear later in the course of the disease. The symptoms continue to progress until the level of disability inhibits the patient’s ability to move independently and they become wheelchair bound. Although the quality of life can be severely compromised due to these symptoms, the life expectancy is approximately equal to that of the general population.