Longitudinal associations between falls and future risk of cognitive decline, the Motoric Cognitive Risk syndrome and dementia: the Einstein Ageing Study

BACKGROUND: falls share risk factors with cognitive decline but whether falls predict cognitive decline, pre-dementia syndromes and dementia is poorly understood. OBJECTIVES: this study aimed to examine if falls are associated with cognitive decline in specific domains and the risk of Motoric Cognitive Risk (MCR) syndrome and dementia. DESIGN: cross-sectional study. METHODS: in older people (age 80.6 ± 5.3 years) free of dementia at baseline, the number of falls (none, one or multiple) during the year before enrolment and the first year of follow-up (exposure) were recorded. Decline in specific cognitive functions (global cognition, episodic verbal memory, verbal fluency, working memory, response inhibition and processing speed-attention), incident MCR and incident dementia were outcome measures. Linear mixed effects models were used to examine the associations between falls and cognitive decline, adjusting for confounders. Cox proportional hazards models were used to determine if falls predicted risk of incident MCR or dementia. RESULTS: of 522 eligible participants, 140 had a single fall and 70 had multiple falls. Multiple falls were associated with a greater decline in global cognition, episodic memory, verbal fluency and processing speed-attention compared to those with no falls (P < 0.05). Over a median follow-up of 1.0 years 36 participants developed MCR and 43 participants developed dementia. Those with multiple falls had a two-fold increased risk of MCR compared to those with no falls, but no increased risk of developing dementia. CONCLUSIONS: multiple falls may be an important marker to identify older people at greater risk of future cognitive decline and incident MCR.