Symptoms of SPMS are similar to those of primary-progressive multiple sclerosis (PPMS). The main symptom of both forms of the condition is gradual worsening of disability.
This may be experienced through increased:
- Numbness or tingling
- Vision problems, such as double vision
- Spasticity or stiffness of the muscles
- Bowel and bladder problems, such as urgent need to urinate
- Problems with cognition, such as learning and memory or information processing
- Difficulty with walking and coordination
Patients with SPMS may experience relapses and remission of symptoms, but the remissions aren’t complete and symptoms often remain present during these times.
Causes and Risk Factors
SPMS can only be diagnosed in patients who have had RRMS, but the cause of SPMS is unknown.
Since the risk of multiple sclerosis is significantly higher when a parent has been diagnosed with the disease, genetic factors may play a role. The unusual relationship between a person's geographic location during childhood and the risk of multiple sclerosis later in life suggests there may be environmental factors at work in the disease.
SPMS affects women twice as often as men and is more common in Caucasian patients.