<prompt> Answer this question truthfullyWhat is the epidemiology and demographics associated with myasthenia gravis?  <response>: <reason> The age of onset in Myasthenia gravis follows a bimodal distribution. The early type before age of 50 is female predominant and the late type after age of 60 is male predominant. Between the age of 50-60 there is no significant different between male and female. 