Does Myasthenia Gravis Get Worse With Age?

Myasthenia gravis (MG) is a chronic autoimmune disease and there is no cure for it. With treatment, the symptoms can be controlled and improve up to a certain extent so that the patients can live a normal or near-normal life.

Patients come to a physician with the initial symptoms of eye muscle weakness, drooping of eyelids and double vision. Almost two-thirds of the patient’s initial symptoms are these and they usually do not complain of fatigue at that stage. Most patients have all those symptoms within 2 years of the first symptoms. In one-sixth of the patient’s weakness of the oropharyngeal muscles, choking, difficulty in swallowing, and difficulty in talking are the initial symptoms. Limb weakness is seen in 10% of myasthenia gravis patients as the initial symptoms. Initial muscle weakness is seen usually, in a group of muscles like the neck, finger extensors or hip flexing muscles. The intensity of the symptoms varies during the day, usually, the symptoms are not present or less severe during the morning and by evening there is marked weakness in the muscles. Also, after prolong use of the muscles the weakness becomes severe.

Myasthenia gravis is a progressive disease however; the course of the disease can be different from person to person and according to the treatment. The main symptoms of myasthenia gravis are fluctuating muscle weakness and fatigability that is seen in a group of muscles or muscles in the whole body. 

The muscle weakness is seen only in eye muscles in 10-40% of patients and they do not develop any other muscle weakness in the body. If these patients have only eye muscle weakness (ocular muscle weakness) for at least one year there is a high chance that it will remain the same and not progress further and these patients have a good prognosis. The rest of the people will have progressive weakness of the oropharyngeal and limb muscles which will develop during the first two years of the disease and eventually they progress into a generalized myasthenia gravis. The involvements, severity, and outcome of myasthenia gravis is determined usually during the first three years of the disease.

There is an active stage in myasthenia gravis where fluctuation of symptoms occurs for a short period then symptoms progress (at a severe stage) for several years. After this, there is an inactive stage where fluctuations occur, but these are due to fatigue and simultaneous infections, not really because of the progressive muscle weakness. After about 15-20 years the muscle weakness becomes fixed and the muscles that are involved severely becomes wasted (atrophied).

There are few factors that can worsen the myasthenia gravis symptoms

Before the treatment with corticosteroids, the weakness is maximum during the first year after the disease for two-thirds of the patients and roughly one-third of patients recover without any treatment, one-third the myasthenia gravis becomes worst and the remaining one-third die of the disease. But with the treatment of corticosteroids, this has changed and more patients live a normal or near-normal life. The goal of treatment is to improve muscle function and prevent breathing and swallowing difficulties.

Myasthenia gravis does get worst with age as it is a progressive autoimmune disease which does not have a cure yet. With treatment, symptoms can be controlled up to some point. However, not all myasthenia gravis patients get worst with age. The patients who only have ocular muscle symptoms (10-40%) only for at least one year will not develop any other muscle weakness in the body most of the time. These patients have a good prognosis. Remaining patients will have progressive development of fluctuating symptoms of muscle weakness and fatigability for several years and then within about 15-20 years this muscle weakness will be fixed and the severely affected muscles gets atrophied.