IMPACT OF SUBJECTIVE COGNITIVE COMPLAINTS ON INSTRUMENTAL ACTIVITIES OF DAILY LIVING IN PATIENTS WITH SUBJECTIVE COGNITIVE DECLINE AND AMNESTIC MILD COGNITIVE IMPAIRMENT: DATA FROM THE CZECH BRAIN AGING STUDY

Abstract

Patients with subjective cognitive decline (SCD) are defined as having newly developed subjective cognitive complaints despite normal performance on standard neuropsychological tests. Some of SCD patients may represent subjects with preclinical Alzheimer's disease. The aim was to analyze their subjectively perceived difficulties with cognitive functioning and with instrumental activities of daily living (IADL) and to compare it to patients with amnestic mild cognitive impairment (aMCI) and cognitively healthy volunteers (HV). In total, 215 non-demented older adults seeking medical help for subjective cognitive complaints were recruited in the Czech Brain Aging Study (CBAS). They underwent a comprehensive neuropsychological examination and were further classified as having aMCI (n=132, mean MMSE=27.2) or SCD (n=83, mean MMSE=29.3). In addition, 25 age and education matched cognitively healthy volunteers without significant subjective cognitive complaints (HV, mean MMSE=29.7) for which they would ever seek for medical help were recruited. All subjects completed a newly developed Motol hospital questionnaire evaluating: 1) the presence/absence of subjective cognitive impairment in various cognitive domains (CD- i.e. memory, attention etc.), 2) the degree of subjectively perceived change in specific cognitive abilities (CA- i.e. remembering names, finding things, word finding difficulties etc.),3) the degree of self-perceived change in demanding IADL (i.e. car driving, using internet banking, using PC etc.). Both SCD and aMCI groups reported more than twice more difficulties in CD and CA than HV (ps<.01) but they did not differ from each other. The SCD group did not differ from HV in subjective worsening of demanding IADL and both groups reported twice less difficulties in IADL than aMCI (ps< .05). The amount of subjective cognitive complaints in SCD patients is similar to that reported by aMCI patients but unlike them it does not seem to have a significant impact on subjective worsening of demanding IADL.