Factors affecting sensitivity and specificity of head-turning sign in the studies

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

BackgroundThe 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.ObjectiveTo assess the prevalence and clinical correlates of the HTS in patients with mild cognitive impairment (MCI) and dementia of various etiologies.MethodsThe 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).ResultsThe 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.ConclusionsIn 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.

"Don't know" sign: description and evaluation of its diagnostic accuracy for cognitive impairment

OBJECTIVES

Patients in neurology clinics are sometimes not aware of the reason for the consultation, and we have called this circumstance the "Don't know" sign (DKS). Our objective was to define this new sign and its modalities and to evaluate its prevalence and its diagnostic accuracy for cognitive impairment (CI) in comparison to other observation-based signs.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional prospective study included all new outpatients evaluated by the authors at neurology consultation.

MEASUREMENTS

We recorded observation-based signs. The Global Deterioration Scale (GDS) was used to assess the cognitive status of patients, based on clinical history, caregiver interview, and cognitive test results. We analyzed the prevalence and the diagnostic accuracy for CI of DKS, "head turning sign," "attending with," verbal repetition, and combinations, calculating sensitivity (Se), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

We enrolled 673 consecutive patients (62% female) with a mean ± SD age of 59.3 ± 20.2 years. DKS was positive in 94 patients (14%) and was strongly associated with GDS score. DKS had a Se of 0.41, Sp of 0.98, PPV of 0.89, and NPV of 0.79 for CI diagnosis. The presence of at least two positive observation signs yielded a Se of 0.50, Sp of 0.97, PPV of 0.86, and NPV of 0.81.

CONCLUSIONS

DKS is frequently observed in neurology outpatients. It has low sensitivity but high specificity and PPV for CI diagnosis. It does not require additional consultation time, and its use can be recommended in combination with other observation-based signs.

Triple Test Plus Rapid Cognitive Screening Test: A Combination of Clinical Signs and A Tool for Cognitive Assessment in Older Adults

Less time-consuming, easy-to-apply and more reliable cognitive screening tests are essential for use in primary care. The aim of this study was to investigate the diagnostic value of the Turkish version of the Rapid Cognitive Screen (RCS-T) and Triple Test individually and the combination of RCS-T with each sign and Triple Test to screen elderly patients for cognitive impairment (CI). A total of 357 outpatients aged 60 or older, who underwent comprehensive geriatric assessment, were included in the study. Presence or absence of attended alone sign (AAS), head-turning sign, and applause sign was investigated. The mean age of the patients was 74.29 ± 7.46. Of those, 61 patients (28 men, 33 women) had Alzheimer's disease (AD), 59 patients had mild cognitive impairment (MCI) (29 men, 30 women), and 237 (80 men, 157 women) were cognitively robust. The sensitivity of the combination of RCS-T and negative for AAS for CI, AD and MCI is 0.79, 0.86 and 0.61, respectively; the specificity was 0.92, 0.93 and 0.92, respectively; and the positive and negative predictive values revealed good diagnostic accuracy. The combination of RCS-T and negative for AAS is a simple, effective and rapid way to identify possible CI in older adults.