CIT-HD: Study in Huntington's Disease

Specific Aims:

1. To examine the effects of sixteen weeks of treatment with the selective serotonin
reuptake inhibitor (SSRI) citalopram compared to placebo on executive function in
patients with early Huntington's disease (HD).

2. To study the relationship between executive function and functional status in patients
with early HD after SSRI treatment.

3. To determine the effect of sixteen weeks of citalopram compared to placebo on other
outcome variables including functional measures (health-related quality of life, work
productivity, and self-reported attention), motor performance, and psychiatric status.

4. To examine the effect of citalopram treatment on volumetric and metabolic (i.e,
N-Acetyl-Aspartate concentration) measures in the neostriatum among patients with
recently diagnosed Huntington's Disease.

Main Hypotheses:

1. At the end of the treatment protocol (i.e., sixteen weeks), patients receiving
citalopram as compared with placebo will show a significantly greater improvement on
tests of executive function.

2. Performance on measures of executive function will be significantly associated with
measures of functional status.

3. At the end of the treatment protocol (i.e., sixteen weeks), patients receiving
citalopram as compared with placebo will show a significantly greater improvement in
functional status and psychiatric ratings; motor score is not expected to change as a
result of citalopram therapy.

4. Using structural MRI and 1H-MRS, after 16 weeks of citalopram treatment, patients with
recently diagnosed Huntington's Disease will show greater changes from baseline on
volumetric and metabolic (i.e., N-Acetyl-Aspartate concentration) neuroimaging measures
in the neostriatum than those on placebo.