highly significantp = 0.0004
This would be consistent with the finding in the same study of highly significant correlations between tryptophan levels in the blood and disease severity as indicated by the number of CAG motif repeats (negative correlation, p = 0.0004), and between the kynurenine:tryptophan ratio and CAG repeat length (positive correlation, p = 0.0025). 16 In neither of these two patient groups is there any available pharmacological strategy for significantly improving the long-term outcome of the brain injury or neurodegeneration, so therapeutic studies to assess responses to drug therapies as performed in osteoporosis patients (above) are not currently possible.