Serotonergic Function and Behavioural and Psychological Symptoms of Frontotemporal Dementia

Frontotemporal lobar degeneration(FTLD) is a common cause of early-onset dementia. FTLD is characterized multiple behavioral symptoms including mental rigidity, irritability, emotional blunting, disinhibition, apathy, and aggression. These behavioural disturbances are particularly important because they increase caregiver burden and may lead to earlier institutionalization. While the causes of FTLD are largely unknown, there is a great deal of evidence suggesting that a brain chemical called serotonin regulates many of the behaviours that are disturbed in FTLD. Our objective is therefore to determine whether dysfunction in the brain's serotonin system is responsible for behavioural problems among FTLD patients. We hope to take the first steps towards a scientific understanding of the behavioural symptoms of FTD, and use our findings to support a larger study optimizing the treatment of targeted behavioural disturbances in FTLD using the antidepressant citalopram. Citalopram increases transmission by serotonin; we plan to use this medication to determine whether there are any differences in how the serotonin system functions in FTLD patients who display different levels of behavioural disturbances. Patients will be given citalopram and will have their blood drawn after 2 and 3 hours to determine plasma levels of the hormones cortisol and prolactin at those times. These hormones are good indicators of serotonergic functioning in the central nervous system. We expect that patients with lower levels of serotonergic functioning will have more severe behavioural disturbances and be less responsive to treatment with citalopram. Following their first test day, we will provide patients with a 6-week supply of citalopram, and assess them for any changes in behaviour at the end of this treatment. This study aims to obtain a better understanding of how changes in the serotonin system relate to behavioural symptoms in FTLD patients. Using the information from this pilot study