Skip to main content
Journal of Medical Genetics logoLink to Journal of Medical Genetics
. 1997 Mar;34(3):229–233. doi: 10.1136/jmg.34.3.229

Mild myotonic dystrophy is associated with memory impairment in the context of normal general intelligence.

J S Rubinsztein 1, D C Rubinsztein 1, P J McKenna 1, S Goodburn 1, A J Holland 1
PMCID: PMC1050898  PMID: 9132495

Abstract

Previous investigations of cognitive function in myotonic dystrophy (DM) suggested that DM subjects have impairment of general intelligence and severe defects in executive function. These studies had to neglect patients with mild clinical disease, since they were generally performed before the availability of DNA testing for DM. We have investigated a group of milder DM cases (defined both by their degree of disability and CTG expansion size) and have not found any defect in general intelligence using the National Adult Reading Test, Standard Progressive Matrices, and Mini-Mental State examination. Three executive function tests were used. The cognitive estimates test and the Wisconsin Card Sorting Test showed tendencies towards impairment, which were of borderline significance, but the verbal fluency task was performed normally. However, in the face of normal general intelligence, mild DM subjects as a group show impairment of memory function. This suggests that memory function may be more sensitive to small CTG repeat expansions than general intelligence.

Full text

PDF
229

Images in this article

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bird T. D., Follett C., Griep E. Cognitive and personality function in myotonic muscular dystrophy. J Neurol Neurosurg Psychiatry. 1983 Nov;46(11):971–980. doi: 10.1136/jnnp.46.11.971. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Chang L., Anderson T., Migneco O. A., Boone K., Mehringer C. M., Villanueva-Meyer J., Berman N., Mena I. Cerebral abnormalities in myotonic dystrophy. Cerebral blood flow, magnetic resonance imaging, and neuropsychological tests. Arch Neurol. 1993 Sep;50(9):917–923. doi: 10.1001/archneur.1993.00540090024006. [DOI] [PubMed] [Google Scholar]
  3. Folstein M. F., Folstein S. E., McHugh P. R. "Mini-mental state". A practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res. 1975 Nov;12(3):189–198. doi: 10.1016/0022-3956(75)90026-6. [DOI] [PubMed] [Google Scholar]
  4. Harley H. G., Rundle S. A., MacMillan J. C., Myring J., Brook J. D., Crow S., Reardon W., Fenton I., Shaw D. J., Harper P. S. Size of the unstable CTG repeat sequence in relation to phenotype and parental transmission in myotonic dystrophy. Am J Hum Genet. 1993 Jun;52(6):1164–1174. [PMC free article] [PubMed] [Google Scholar]
  5. Harper P. S. Congenital myotonic dystrophy in Britain. I. Clinical aspects. Arch Dis Child. 1975 Jul;50(7):505–513. doi: 10.1136/adc.50.7.505. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Hunter A., Tsilfidis C., Mettler G., Jacob P., Mahadevan M., Surh L., Korneluk R. The correlation of age of onset with CTG trinucleotide repeat amplification in myotonic dystrophy. J Med Genet. 1992 Nov;29(11):774–779. doi: 10.1136/jmg.29.11.774. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Nelson H. E. A modified card sorting test sensitive to frontal lobe defects. Cortex. 1976 Dec;12(4):313–324. doi: 10.1016/s0010-9452(76)80035-4. [DOI] [PubMed] [Google Scholar]
  8. Portwood M. M., Wicks J. J., Lieberman J. S., Duveneck M. J. Intellectual and cognitive function in adults with myotonic muscular dystrophy. Arch Phys Med Rehabil. 1986 May;67(5):299–303. [PubMed] [Google Scholar]
  9. Shallice T., Evans M. E. The involvement of the frontal lobes in cognitive estimation. Cortex. 1978 Jun;14(2):294–303. doi: 10.1016/s0010-9452(78)80055-0. [DOI] [PubMed] [Google Scholar]
  10. Wieringa B. Myotonic dystrophy reviewed: back to the future? Hum Mol Genet. 1994 Jan;3(1):1–7. doi: 10.1093/hmg/3.1.1-a. [DOI] [PubMed] [Google Scholar]
  11. Wilson B., Cockburn J., Baddeley A., Hiorns R. The development and validation of a test battery for detecting and monitoring everyday memory problems. J Clin Exp Neuropsychol. 1989 Dec;11(6):855–870. doi: 10.1080/01688638908400940. [DOI] [PubMed] [Google Scholar]
  12. Woodward J. B., 3rd, Heaton R. K., Simon D. B., Ringel S. P. Neuropsychological findings in myotonic dystrophy. J Clin Neuropsychol. 1982 Dec;4(4):335–342. doi: 10.1080/01688638208401141. [DOI] [PubMed] [Google Scholar]

Articles from Journal of Medical Genetics are provided here courtesy of BMJ Publishing Group

RESOURCES