METHODS: All available genetically diagnosed patients studied by us in 2010 (n = 41) were invited to the follow-up study; assessment of motor function (MFM-32), muscle strength (MRC %)and respiratory function (FVC %) and prime assessor were the same as in the initial study. Patients were asked whether the course of disease had progresses, was stable or had improved.
RESULTS: 23 patients (15-61 y) accepted the invitation. Mean follow-up time was 7.7 years. Loss of muscle strength was more prominent in patients with mutations in DNM2, RYR1 and TPM2/3 genes and deterioration in FVC % was more evident in patients carrying NEB and ACTA1 gene mutations. MFM-sum score was less sensitive to change compared to MRC-sum score. In general, agreement between the patient\'s own opinion of the course of disease and results of assessments was good.
CONCLUSIONS: The number of patients in the study is too small to be conclusive, but the results indicate that CM can be stable or slowly progressive depending on the genetic subtype.