COGNITIVE FUNCTION IN MYOTONIC-DYSTROPHY - A FOLLOW-UP-STUDY

Intellectual and cognitive function were studied in 35 patients with m yotonic dystrophy (DM). All 5 patients with the congenital form showed moderate or mild mental retardation. The 30 adult-onset patients had normal intelligence and memory quotients. In this adult-onset group no differences in cognitive function were observed either with respect t o sex or physical disability. The sex of the affected parent, mother v s. father, was also without effect in this group. A follow-up study wa s performed in 16 patients with a mean test interval of 12 years. Ther e was no severe cognitive impairment over this time span or a signific ant correlation between the progression of physical and cognitive dysf unction.