Objectives: To evaluate the prevalence and utility of memory complaint in a geographically representative cohort and, in cases with mild cognitive impairment (MCI), to determine whether memory complaint alters 10-year trajectories of disability in activities of daily living (ADLs), Short Portable Mental Status Questionnaire (SPMSQ) score, and 20-item word recall.
Design: Prospective cohort study.
Setting: Washington and Iowa counties, Iowa.
Participants: Iowa Established Populations for Epidemiologic Studies of the Elderly (N = 3,673; aged > or =65; 61.3% female; 99.9% white).
Measurements: Age, sex, education, SPMSQ score, 20-item word recall, ADL or instrumental ADL disability, and chronic medical conditions.
Results: The prevalence of memory complaint was 34%. Although proportionally more cognitively impaired individuals were in the memory complaint group (34% vs 27%), the pattern of subclassification into cognitively intact and MCI Stage 1 and 2 subgroups was similar for people with and without memory complaint. Median SPMSQ score and number of words recalled at baseline were comparable across memory complaint categories in each subgroup. MCI participants without subjective memory complaint constituted a larger proportion of the overall sample than individuals with subjective memory complaint (460 (14%) vs 295 (8.9%)) and of persons objectively classified as having MCI (61% vs 39%). The distribution of individual 10-year change in ADL disability, SPMSQ score, and word recall were similar for those with and without memory complaint across all subgroups of cognitive impairment.
Conclusion: Memory complaint is not necessary for MCI diagnosis and does not distinguish cases with different progression rates in disability or cognitive impairment. 2006.