This disease causes a progressive degeneration of the myelin sheath and the nerve fibers in the central nervous system (CNS), which can lead to a wide range of symptoms.
Fatigue
According to the National Multiple Sclerosis Society (NMSS), about 80 percent of MS patients will experience fatigue that can become severe enough to interfere with daily responsibilities at home and work. This may be the most common symptom associated with MS and one of the earliest notable signs in a patient who has otherwise been healthy and had no or minimal physical limitations in the past.
The Nervous System
MS causes the immune system to attack the myelin sheath that insulates and protects the nerve fibers, and, eventually, the nerve fibers themselves. As the myelin is attacked, it causes scarring, also called sclerosis, which can cause signals to and from the brain to become scrambled or not be transmitted at all.
This interruption in signal transmission can affect the body’s organs, muscles and tissues, which can lead to a number of characteristic MS symptoms, including numbness, dizziness, memory problems, personality changes and depression. Mood changes can be a result of the disease or a secondary condition that arises from the stress and frustration of living with the disease. While headaches are not a common MS symptom, some patients will develop chronic or regularly recurring headaches as one of the symptoms of the disease.
Another symptom that may develop in more advanced cases is seizures, which are estimated to occur in up to 5 percent of MS patients.
Vision Problems
Because MS causes the immune system to attack the optic nerve, vision problems are often early symptoms associated with the onset of the disease. Patients may experience blurry or double vision, pain when moving the eyes, problems with depth perception or color contrast. This symptom may come on gradually or suddenly and may affect one or both eyes.
Most people with MS will experience some degree of vision problems, but for most, the symptoms can be managed or corrected with steroid treatments.
Mouth, Throat and Lungs
According to the National Multiple Sclerosis Society, MS can cause a wide range of speech problems, which can range from slurred words to problems with articulation and volume control. For other patients, changes can include altered vocal quality, which can include hoarseness or sounding breathless. These problems can be the result of problems breathing or from damaged or weakened nerves in the chest.
In rare cases, patients may experience problems with breathing that can be dangerous as the disease progresses and attacks the nerves that control the muscles responsible for breathing. For most patients who develop this complication, respiratory therapy helps manage it.
Still other patients develop problems swallowing, which may be caused by damage to the muscles that control these actions. This can cause food or drink to be aspirated into the lungs, resulting in infections, along with an increased choking risk.
Extremities
The majority of MS patients will experience problems with their limb functions, which can range from mild -- such as numbness or tingling in the early stages of the disease, to muscle weakness, problems with gait and coordination, and balance issues as the disease progresses. For some patients, this means that living with MS will also mean learning to use canes, walkers or wheelchairs. Physical therapy and other technologies can help manage muscle control and strength in many patients. Immobility may lead to pressure sores, or bedsores. Immobile patients will experience more rapid and severe loss in muscle tone, as well as more progressive weakness, than those who remain active.
Some MS patients will develop tremors, or uncontrollable shaking, as a result of damage to the nerve pathways that are responsible for movement, although this symptom is less common than other physical symptoms of the disease. Other patients will experience regular, uncomfortable itching, called pruritus, as one of the sensations that comes with the jumbled nerve transmissions.
Skeletal Problems
Limited motion, the effects of MS medications and other factors can put MS patients at an increased risk for developing skeletal problems, such as osteoporosis. MS patients who have weakened bones are more likely to have broken or fractured bones.
Bladder and Bowel Problems
More than 80 percent of MS patients will develop some level of bladder dysfunction, according to the NMSS, with some experiencing problems to the point where a catheter is necessary. The damage to the nerves that control the bladder can result in frequent urinary tract infections (UTIs), as well as bladder and kidney infections.
Patients may develop bowel problems that can range from constipation to diarrhea or loss of bowel control altogether.
Reproductive Damage
MS doesn’t impact fertility -- and many women find that their symptoms ease during the pregnancy, but up to 40 percent of women will experience a relapse postpartum. MS patients often experience other reproductive issues, however, which can include problems with arousal and orgasm. Other patients may shy away from intimacy because other symptoms of MS, such as fatigue and pain, can make sexual intimacy seem daunting or unattractive. For others, the depression and emotional issues commonly associated with MS can make intimacy a challenge.
If you or a loved one suffers from MS, it's important to communicate with health care providers about new or progressively worse symptoms.