Herein, we presented a patient with FTD successfully treated for his BPSD with escitalopram.
The NPI-Q is a two-page self-administered questionnaire that has written instructions for completing the questionnaire form . It can evaluate symptom severity and caregiver distress. The NPI-Q total severity score and total caregiver score were measured, which excluded the assessments of nighttime disturbances and appetite/eating disturbances. His wife checked the NPI-Q. The anxiety, irritability/lability, aberrant motor and appetite/eating disturbances scores were reduced after starting escitalopram 5 mg.
The SRI is a useful instrument for assessing five distinctive stereotypic behavioral disturbances, eating and cooking behaviors, roaming, speaking, movements and daily rhythm, which are often seen in patients with FTD . The SRI uses the same technique as the NPI in that both the frequency and the severity of each behavior are determined. The scores for roaming, speaking and daily rhythm were reduced after treatment with escitalopram 5 mg/day, and eating and cooking was reduced after increasing the escitalopram dosage to 10 mg/day.
The Food and Drug Administration (FDA) do not currently have any approved drugs for the treatment of FTD . Serotonin reuptake inhibitors (SSRIs) may be useful for reducing the severity of compulsion, agitation, aggressiveness, impulsivity, irritability, eating behavior disruptions, and disinhibition [7, 8]. Studies of sertraline efficacy in treating FTD symptoms have been mainly limited to observational studies. Sertraline has been shown to improve behavior in several open-label trials in FTD patients [8, 9]. One open-label 12-week trial showed a treatment response with fluvoxamine administration from a dosage range of 50–150 mg/day, improving stereotypic behavior, eating behavior, and roaming behavior . It has been proposed that fluvoxamine and topiramate may be considered treatment options in the clinical phenotype of repetitive and compulsive habits in behavioral FTD . In a systematic review, SSRIs such as citalopram and paroxetine reduced multiple symptoms, including disinhibition, hyperorality, and depression .
Citalopram is a racemate consisting of the S(+)-enantiomer (escitalopram) and R(-)-enantiomer (R-citalopram) in a 1:1 ratio . R-citalopram was approximately 150 times less potent than escitalopram in an in vitro rat brain synaptosome system regarding serotonin reuptake inhibitor activity [14, 15]. Additionally, escitalopram, as an inhibitor of transporter activity, is approximately twice as potent as citalopram and at least 27-fold more potent than R-citalopram in experiments using cultured cells expressing the human serotonin transporter protein . Escitalopram has been shown in nonclinical experiments to have greater efficacy than equivalent doses of citalopram . Wiborg et al suggested that R-citalopram reduces the on-rate of S-citalopram to the transporter, possibly via an allosteric site. This was attributed to the R-enantiomer having a counteracting effect on the S-enantiomer . The detailed molecular basis for this effect remains to be identified, but pharmacological studies have suggested that the R- and S-enantiomers interact at the level of the serotonin transporter protein by a mechanism other than simple antagonistic occupation of the high-affinity binding site . Escitalopram showed better efficacy than citalopram, with higher response and remission rates and faster time to symptom relief . Citalopram was shown to be significantly less effective than escitalopram in achieving acute responses in a Cochrane systematic review . Network meta-analysis showed significantly greater efficacy with escitalopram than citalopram for depression . Taking these findings into account, it has been suggested that escitalopram might have clinically better efficacy than citalopram for the treatment of depression because of its potent inhibition of serotonin transporters.
To the best of our knowledge, this is the first case demonstrating the efficacy of a low dose of escitalopram, only 5 mg/day, for behavioral and psychiatric symptoms associated with FTD.