Evaluation of Symptoms in Persons with Subjective Cognitive Impairment

Abstract

Background: There is a pre-dementia and pre-mild cognitive impairment (MCI) stage of eventual Alzheimer's disease (AD) in which persons have subjective complaints of impairment in the absence of objective deficits. Little is known about the sensitivity and specificity of scales developed to assess these subjective deficits. This may be crucial for scientific efforts to sensitively identify prevention modalities.

Methods: We conducted a study in which aconsecutive series of 42 subjects presentingwith Subjective Cognitive Impairment (SCI) wereevaluated with the scales described below and compared the scales with respect to demographic variables, mental status and psychometric test results (see Table for demographic characteristics). Subjects with SCI, Global Deterioration Scale (GDS) stage 2, were evaluated on 5 subjective assessment questionnaires. The questionnaires usedfor all subjects were: the self-rated Visual Analogue Scale (VAS), (Guillo Benarous, 2013); and the Brief Questionnaire Regarding Severity of Memory & Emotional Problems (BQRS-M&E), (Reisberg, 2013). The Memory Complaint Questionnaire (MAC-Q) was also used in our study. Randomly alternating subjects (N=19) were additionally evaluated on time related scales: the Saykin, ADNI Self Report Index (Saykin, version 12-29-12), and the Sahlgrenska Academy Self-reported Cognitive Impairment Questionnaire (SASCI-Q), part 2. Subjects in the second random sequence (n=23), were evaluated on the Saykin scale modified for severity (Saykin-mod-sev), (Saykin, Reisberg modification, 2013), and an Emotional Severity Scale (ESS), (Guillo BenArous, 2013). We compared the scales with respect to scores on a battery of psychological tests and demographic variables, specifically, age, gender, and education.

Results: We found a significant relationship between the Saykin ADNI Self Report Index and the Trail Making Test B (P=0.009) (see figure). We also found a significant relationship between the Visual Analogue Scale and the Paired Associates Delayed Recall measure (p=0.028). For the demographic variables a significant relationship was found with selected tests (see Figure).

Conclusions: These findings could be of relevance for future prevention trials. Ultimately, we need to determine the sensitivity of temporally based scales in comparison with severity based scales and identify optimal predictors of eventual MCI and AD.