Abstract
Background: Frontotemporal dementia (FTD) is characterized by a number of
prominent behavioral changes. While FTD has been associated with the presence of aberrant
or unusual sexual behaviors in a proportion of patients, few studies have formally
investigated changes in sexual function in this disease.
Objective: We aimed to systematically quantify changes in sexual behavior,
including current symptoms and changes from prior diagnoses, in behavioral-variant (bvFTD)
and semantic dementia (SD), compared to Alzheimer’s disease (AD).
Methods: Carers of 49 dementia patients (21 bvFTD, 11 SD, 17 AD) were
interviewed using the Sexual Behavior and Intimacy Questionnaire (SIQ), a survey designed
to assess changes in sexual function across multiple domains including initiating, level
of affection, and aberrant or unusual sexual behavior.
Results: BvFTD patients show prominent hyposexual behavior including
decreased affection, initiation, and response to advances by partners, and decreased
frequency of sexual relations, compared to AD and to SD patients. The greatest changes in
sexual behavior compared to pre-diagnoses were found in the bvFTD group with a 90–100%
decrease in initiation, response, and frequency of sexual relations. Notably, aberrant or
unusual sexual behavior was reported in a minority of bvFTD and SD patients and occurred
in patients who also showed hyposexual behavior toward their partner.
Conclusion: Overall loss of affection, reduced initiation of sexual activity,
and responsiveness is an overwhelming feature of bvFTD. In contrast, aberrant or unusual
sexual behavior is observed in the minority of bvFTD patients. The underlying
pathophysiology of these changes likely reflects structural and functional changes in
frontoinsular and limbic regions including the hypothalamus.
