Balance and strength measures are associated with incident dementia in older men

Background

As people age the risk of dementia increases. Balance and strength deteriorate with ageing, but their associations with dementia are not clear. We aimed to determine relationships of balance and strength performance with incident dementia in the Health in Men Study (HIMS) cohort.

Methods

We used wave 4 of the HIMS as baseline for analyses (2011–2013), following 1261 men until December 2017 via data linkage to determine incident dementia. Balance was measured using a modified Balance Outcome Measure for Elder Rehabilitation (mBOOMER) Score and strength with the knee extension test. Cox proportional hazards regression was used, adjusting for sociodemographic and health data. Strength and balance scores were analysed non-linearly using restricted cubic splines.

Results

13.7% of men were diagnosed with dementia over a mean period of 4.7 (SD 1.5) years. Higher baseline mBOOMER scores were associated with a reduced risk of incident dementia, with greater changes in risk at higher mBOOMER scores (9 vs 8: HR 0.80, 95% CI 0.73–0.88; 12 vs 11: 0.49, 95% HR 0.36–0.68). Higher baseline lower limb strength was associated with a reduced risk of incident dementia, with greater changes occurring at lower scores, plateauing at around 25 kg (5 vs 4: HR 0.93, 95% CI 0.89–0.98; 25 vs 24: HR 0.99, 95% CI 0.95–1.03).

Conclusions

This study demonstrated a non-linear association of better performance in both strength and balance with reduced likelihood of incident dementia. These results raise the hypothesis that strategies to improve strength and balance could reduce the incidence of dementia in older men.