Forty-two patients suffering from myasthenia gravis were examined in a longitudinal study design. The aim of the study was to investigate possible psychosocial predictors for the course of the disease. At the time of the first examination (T1) the diagnosis myasthenia gravis had been established for no longer than 1 year. Two further examinations were done at 6 months (T2) and 18 months (T3) after T1. Methods consisted of a personality questionnaire (FPI), a coping questionnaire (FKV), an assessment of neurotic symptoms by interviewers (PSKB) and an assessment of the doctor-patient relationship by the attending physicians. Two different severity scores (Oosterhuis Index, Myasthenia Score) served as criteria for the course of the disease. There was no connection between the course of myasthenia gravis and neurotic symptoms like anxiety or depression and the quality of the doctor-patient relationship (both assessed at T1). Also demographic data were independent from the development of severity scores. The personality factor extraversion was associated with a positive course of the disease, aggressiveness and worrying about health with a negative one. Among the coping behaviors religiousness and looking for sense were associated with a favorable course but that was shown only regarding the Oosterhuis Index and not the Myasthenia Score. As several T1 personality factors were predictive for the severity scores at T3, these results may suggest a causal influence of personality factors on the severity of the illness. Whether or not this relationship is actually in operation, however, remains ellusive. Further studies using an experimental design are needed to strengthen this hypothesis.