Clinical and imaging correlates of hyperorality in syndromes associated with frontotemporal lobar degeneration

Empirical research investigating hyperorality in syndromes associated with frontotemporal lobar degeneration (FTLD) is limited. The present study aims to assess and describe hyperorality and its clinical and imaging correlates in patients with FTLD-associated syndromes.

This retrospective longitudinal study included consecutive patients with FTLD who underwent a clinical, cognitive, and behavioral assessment. The presence and severity of hyperorality was assessed using the Frontal Behavior Inventory.

A total of 712 patients with FTLD were included in the study. Hyperorality was reported by 29% (204 of 712 [95% CI: 25-32%]) of patients; was more frequent in those with severe dementia than in those with prodromal or mild to moderate dementia (P < 0.05); was associated with younger age (odds ratio [OR] = 0.96 [95% CI: 0.94-0.99]), (P = 0.003) and positive family history for dementia (OR = 2.03 [95% CI: 1.18-3.49], P = 0.010); was overall more probable in the behavioral variant of frontotemporal dementia (bvFTD) and frontotemporal dementia with amyotrophic lateral sclerosis phenotypes, and less probable in other language or motor phenotypes; and was associated with higher severity of neuropsychiatric symptoms (OR = 1.08 [95% CI: 1.06-1.10], P < 0.001) and with the presence of several behavioral symptoms (P < 0.05). Moreover, hyperorality severity increased over time only in patients with bvFTD (β = +0.15, P = 0.011) or semantic variant of primary progressive aphasia (β = +0.34, P = 0.010). Finally, the presence of hyperorality was significantly associated with greater atrophy in the right anterior insula and right orbitofrontal region (false discovery rate-corrected P < 0.05).

Hyperorality is common in certain FTLD-associated syndromes. Understanding its correlates can help clinicians define pharmacological and educational interventions and clarify related anatomical circuits.