Subjective Memory Complaints and Incident Dementia in a High Risk Older Adult Hypertensive Population

Background: there is a growing body of evidence demonstrating an association between subjective memory complaints (SMC) and an increased risk of incident cognitive decline or dementia. To date this has not been examined in hypertensive older adults, a prevalent and growing population group at high risk of cognitive decline.

Methods: using data from participants in the Hypertension in the Very Elderly Trial cohort the association between baseline SMC and incident cognitive decline and dementia was examined using Cox proportional hazard regression. Cognitive function was assessed using the Mini-Mental State Exam and diagnoses of dementia were made using standard diagnostic criteria. SMC was assessed by the question 'do you feel that you have more problems with memory than most?' Analyses were rerun to examine the associations by level of baseline cognitive function, to evaluate the role of SMC by dementia type and by sex.

Results: baseline SMC were associated with an increased risk of developing any dementia (hazard ratio (HR)1.63 (95% confidence intervals (CI): 1.18:2.25)), Alzheimer's disease (HR1.59 (95% CI: 1.08:2.34)) and vascular dementia (HR2.05 (95% CI: 1.19:3.54)). Similar patterns were seen across all levels of baseline MMSE but were strongest in those with scores of 25-27. There were no clear differences by sex.

Discussion: a positive report of SMC assessed by a single question in an older adult with hypertension raises the possibility of increased risk of incident dementia. As such its use may be a useful addition to the repertoire of the general practitioner and geriatrician when assessing older adults.