Prevalence and correlates of the head turning sign in mild cognitive impairment and dementia due to neurodegenerative, chronic cerebrovascular, and mixed etiologies.

Background: The head turning sign (HTS) consists in the patient turning his/her head towards the accompanying person in search for support when being asked questions. Although the HTS is known to be associated with cognitive impairment, previous investigations were biased towards Alzheimer's disease (AD) or did not differentiate between diverse dementia etiologies; moreover, little is known about the specific cognitive correlates of the HTS.

Objective: To assess the prevalence and clinical correlates of the HTS in patients with mild cognitive impairment (MCI) and dementia of various etiologies.

Methods: The HTS was recorded during the Mini-Mental State Examination (MMSE) in 232 MCI/dementia patients with the following etiological classification: AD (N = 121); frontotemporal lobar degeneration (FTLD; N = 24); Lewy body disease (LBD; N = 11); vascular (N = 29); mixed (N = 47).

Results: The overall prevalence of the HTS in the whole cohort was 27.6%. Albeit being descriptively higher in dementia (29.9%) versus MCI (22.7%), as well as descriptively lower in FTLD and LBD than in remaining subgroups, no significant association was detected between the HTS and either MCI/dementia status or etiology. HTS + patients were older and more frequently females, also reporting lower MMSE scores and differing from HTS- ones on Temporal and Spatial Orientation and Constructional Praxis sub-scores. An association between the HTS and lower MMSE scores was found in patients with MCI but not in those with dementia.

Conclusions: In patients with cognitive impairment due to diverse causes, the HTS might occur regardless of MCI versus dementia status and across different etiologies. MCI patients displaying the HTS might have more severe cognitive deficits.