Myo-inositol Levels Higher in Adults with Down Syndrome
Higher concentrations associated with reduced cognitive ability
FRIDAY, Dec. 9 (HealthDay News) -- Adults with Down syndrome have a higher concentration of myo-inositol in the hippocampus and this may predispose them to development of Alzheimer disease later in life, according to a study published in the December issue of the Archives of General Psychiatry. The transporter gene for myo-inositol, which affects neuron survival and function, is located on chromosome 21.
Declan G. M. Murphy, M.D., of the Institute of Psychiatry, London, and colleagues conducted a case-controlled study of 38 adults with Down syndrome without dementia and 42 healthy controls of similar age, ethnic origin, apolipoprotein E status and handedness.
The authors used the Cambridge Cognitive Examination to assess cognitive performance and also measured hippocampal myo-inositol concentration.
Among those with Down syndrome, hippocampal myo-inositol was significantly higher than among the controls, the investigators found. And there was a significant negative association between increased myo-inositol concentration and overall cognitive ability in those with Down syndrome.
"There is, at present, no treatment for cognitive impairment in Down syndrome. However, the possibility that increased myo-inositol concentration in the Down syndrome brain may be associated with a greater degree of mental retardation and/or later Alzheimer disease suggests that trials are required to determine whether reduction in brain myo-inositol concentration improves cognitive outcome in Down syndrome," the authors conclude.