Multiple sclerosis is a chronic disease in which myelin is damaged, leading to difficulties with movement, thinking and sensation. Myelin is a protective covering of nerves in the central nervous system that helps to quicken signals between the brain and the body. Late-onset multiple sclerosis is defined as having an initial diagnosis of the condition after the age of 50 years, as the usual onset is between the ages of 20 and 40 years, according to a review of research in the November 2004 issue of "Neurological Sciences."
Movement Difficulties
Difficulties with movement is the most common symptom of late-onset multiple sclerosis. According to a study led by Dr. Michael Polliack in the February 2001 edition of the "Journal of the American Geriatrics Society," over 60 percent of individuals with late-onset multiple sclerosis report motor difficulties at the beginning of the condition. Movement difficulties depend upon which nerves of the central nervous system were affected. Muscles rely on nerve impulses from the brain to move. Nerve impulses are often distorted, slowed or inhibited when nerves are damaged, so the affected body part does not move properly. Individuals with motor deficits may sway or stumble when walking, or have difficulty controlling arm movements. Speech may be slowed or slurred.
Abnormal Sensations
Individuals with late-onset multiple sclerosis often experience abnormal sensations. According to the study by Dr. Polliack in the "Journal of the American Geriatrics Society," 30 percent of people with late-onset multiple sclerosis report sensory disturbances at the start of the disease. Numbness, tingling, burning and feeling like the skin is being pricked by pins and needles are common sensations felt by those with multiple sclerosis. These sensations are usually felt on the arms, hands, legs or feet, but they may be felt anywhere on the body. Myelin destruction of the nerves in the central nervous system results in the abnormal sensations. Sometimes the sensations are mild and temporary, but sometimes they are so bothersome that they inhibit everyday functioning.
Lhermitte's symptom, an electrical sensation that shoots down the back and into the limbs, is another common sensation among individuals with multiple sclerosis. Bending the neck forward or backward usually triggers the electrical sensation of Lhermitte's symptom. A person with multiple sclerosis may also experience Uhthoff's phenomenon, or a worsening of multiple sclerosis symptoms when overheated. Hot baths, fever, hot weather or exercise may spark Uhthoff's phenomenon.
Depression
Individuals with late-onset multiple sclerosis may experience depression. According to the study by Dr. Polliack in the "Journal of the American Geriatrics Society," about 23 percent of people with late-onset multiple sclerosis have a major depressive episode within 4 years of the diagnosis of multiple sclerosis. Symptoms of a major depressive episode include feeling sad or down, loss of interest in enjoyable activities, changes in sleep, low energy, changes in appetite, feelings of guilt, concentration difficulties and suicidal thoughts.
References
- "Journal of the American Geriatrics Society"; Late-Onset Multiple Sclerosis; Michael Polliack M.D., Yoram Barak M.D., and Anat Achiron M.D. Ph.D.; February 2001.
- "Neurological Sciences"; Late Onset Multiple Sclerosis: Clinical Characteristics, Prognostic Factors and Differential Diagnosis; Vittorio Martinelli, M.D., Mariemma Rodegher, M.D., Lucia Moiola, M.D., and Giancarlo Comi, M.D.; November 2004
