Epidemiology Of Myasthenia Gravis


The prevalence of myasthenia gravis in the United States is estimated at 14 to 20 per 100,000 population, approximately 36,000 to 60,000 cases in the United States. However, myasthenia gravis remains underdiagnosed and the prevalence is probably higher. Previous studies have shown that women are more often affected than men. The most common age at onset is the second and third decades in women and the seventh and eighth decades in men. As the population ages, the average age at onset has increased correspondingly, and now males are more often affected than females, and the onset of symptoms is usually after age 50. A 2015 study in acetylcholine receptor antibody (AChR-Abs) positive Caucasian has demonstrated that there is no specific causal gene for myasthenia gravis there are specific regulatory genes that influence immune regulation. In addition, about 3% of the study population had a primary relative with myasthenia gravis suggesting a small but distinct but not direct genetic influence.

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