Episodic memory is impaired in Alzheimer’s disease (AD) dementia but thought to be relatively spared in behavioral variant frontotemporal dementia (bvFTD). This view is challenged by evidence of memory impairment in bvFTD. This study investigated differences in recognition memory performance between bvFTD and AD.

We performed a retrospective analysis on the recognition trial of the Rey Auditory Verbal Learning Test in patients with bvFTD (n = 85), AD (n = 55), and control participants (n = 59). Age- and education-adjusted between-group analysis was performed on the total score and indices of discriminative ability and response bias. Correlations between recognition and measures of memory, language, executive functioning, and construction were examined.

Patients with AD had a significantly lower total recognition score than patients with bvFTD (control 28.8 ± 1.5; bvFTD 24.8 ± 4.5; AD 23.4 ± 3.6, p < .01). Both bvFTD and AD had worse discriminative ability than controls (A’ control 0.96 ± 0.03; bvFTD 0.87 ± 0.03; AD 0.84 ± 0.10, p < .01), but there was no difference in response bias (B” control 0.9 ± 0.2; bvFTD 1.6 ± 1.47; AD 1.4± 1.4, p < .01). AD had worse discriminability than bvFTD (p < .05). Discriminability was associated with memory for both patient groups (median correlation coefficient r = .34) and additionally associated with language (r = .31), but not executive functioning (r = −.03) in bvFTD. Response bias was unrelated to other cognitive functions (r = −.02).

Discriminability, but not response bias, differentiated patients with bvFTD from AD. The presence of an impaired discrimination index suggests a “pure” (recognition) memory deficit in bvFTD.

Previous studies in western countries have shown that about 30%–50% of patients with frontotemporal lobar degeneration (FTLD) have a positive family history, whereas the few epidemiological studies on FTLD done in Asia reported much lower frequencies. It is not clear the reason why the frequencies of FTLD with positive family history were lower in Asia. Furthermore, these findings were not from studies focused on family history. Therefore, it is necessary to conduct further studies on the family history of FTLD in Asia. This international multi-center research aims to investigate the family histories in patients with FTLD and related neurodegenerative diseases such as progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), and motor neuron diseases in a larger Asian cohort.

Participants were collected from five countries: India, Indonesia, Japan, Taiwan, and Philippines. All patients were diagnosed with behavioral variant frontotemporal dementia (bvFTD), semantic dementia (SD), progressive non-fluent aphasia (PA), frontotemporal dementia with motor neuron disease (FTD/MND), PSP, and corticobasal degeneration (CBD) according to international consensus criteria. Family histories of FTLD and related neurodegenerative diseases were investigated in each patient.

Ninety-one patients were included in this study. Forty-two patients were diagnosed to have bvFTD, two patients had FTD/MND, 22 had SD, 15 had PA, one had PA/CBS, five had CBS and four patients had PSP. Family history of any FTLD spectrum disorder was reported in 9.5% in bvFTD patients but in none of the SD or PA.

In contrast to patients of the western countries, few Asian FTLD patients have positive family histories of dementia.