Hypersexual Behavior in Frontotemporal Dementia: A Comparison with Early-Onset Alzheimer’s Disease

Abstract

The basis of hypersexual behavior among patients with dementia is not entirely clear. Hypersexual behavior may be a particular feature of behavioral variant frontotemporal dementia (bvFTD), which affects ventromedial frontal and adjacent anterior temporal regions specialized in interpersonal behavior. Recent efforts to define Hypersexual Disorder indicate an increasing awareness of heightened sexual activity as a source of personal distress and functional impairment, and clarification of hypersexuality in bvFTD could contribute to understanding the neurobiology of this behavior. This study reviewed 47 patients with bvFTD compared to 58 patients with Alzheimer’s disease (AD) for the presence of heightened sexual activity to the point of distress to caregivers and others. Hypersexual behavior occurred in 6 (13%) bvFTD patients compared to none of the AD patients. Caregivers judged all six bvFTD patients with hypersexual behavior as having a dramatic increase in sexual frequency from premorbid levels. All had general disinhibition, poor impulse control, and actively sought sexual stimulation. They had widened sexual interests and experienced sexual arousal from previously unexciting stimuli. One patient, with early and predominant right anterior temporal involvement, was easily aroused by slight stimuli, such as touching her palms. Although previously considered to be predominantly disinhibited sexual behavior as part of generalized disinhibition, these patients with dementia illustrate varying degrees of increased sexual desire. We conclude that bvFTD is uniquely associated with hypersexuality; it is more than just cognitive impairment with frontal disinhibition but also involves alterations in sexual drive, possibly from right anterior temporal-limbic involvement in this disease.

Characterizing Sexual Behavior in Frontotemporal Dementia

“…The findings of hyposexuality in our FTD cohorts, particularly in the bvFTD group, contrasts with previous studies that have reported hypersexuality and aberrant sexual behavior in this syndrome [11,12]. This difference may be due to the fact that these studies used retrospective case note review looking for documentation of hypersexual behavior and did not look for evidence of hyposexual behavior.…”

“…Previous reports on sexual function [11,12] in FTD have highlighted the occurrence of hypersexual and aberrant sexual behavior, yet the incidence of such behavior in these studies has been rather low, between 13% [12] and 17% [11]. In the current study, we found that bvFTD is characterized by hyposexual behavior that represents a change from their behavior prior to symptom onset.…”

“…Hypersexual and aberrant sexual behavior has previously been suggested to arise from alterations in the right hemisphere reward pathways [11], and changes in sexual drive related to right anterior temporal limbic involvement [12,15]. As mentioned, one previous study has alluded to the presence of hyposexual behavior in FTD, with 54% of FTD caregivers reporting hyposexual behavior versus 23% in AD patients, and suggested that this may represent one of the first presenting symptoms of FTD [13].…”

“…Disinhibition is commonly reported in the behavioral variant of FTD (bvFTD) [7] and has led to the assumption that bvFTD patients exhibit hypersexual behavior. Perhaps surprisingly, there has been little examination of sexual function in bvFTD, other than isolated reports [8][9][10] and series [11,12] using retrospective case note analyses, documenting hypersexuality and aberrant behaviors in a proportion of cases. One previous study that used a carer survey suggested that hyposexuality may be the dominant behavioral change [13].…”

Addressing Sexuality in Dementia: A Challenge for Healthcare Providers

“…The second type is sexually disinhibited behaviour, which is part of the general behavioural disinhibition in dementia (e.g. lewd language, exhibitionism, repeating attempts to have sex, aggressive sexual demands) [20,21].…”