Gait Speed and Evolution of Verbal Fluencies in Frail or Prefrail Older People with Type 2 Diabetes. A Pilot Study

Type 2 diabetes (T2D) is a risk factor of frailty and cognitive impairment. Impaired gait in older people is associated with incident vascular dementia. We aimed to assess whether in frail or prefrail older subjects with T2D, lower gait speed can be associated with faster cognitive decline.

Case-control study nested in a large randomized control trial (RCT, MID-frail); post hoc analysis.

Older frail and prefrail subjects (>70y) with T2D and with no history of cognitive problems were enrolled in a single recruiting center. Participants were divided into two groups depending on their walking speed - above (fast walkers) or below (slow walkers) using a cut off of 1 m/sec.

Cognitive function was assessed at baseline and during follow-up with the MMSE, category and letter fluencies at 15 sec (initiation) and 15-60 sec (late).

48 subjects were included, 22 were fast walkers, 26 were slow walkers. The mean follow-up was 60.9 (SD 17.5) weeks. The baseline 0-15 sec letter fluency was higher in fast walkers (p=0.008). There was no difference at baseline with MMSE scores and category fluency. The MID-Frail intervention did not change the evolution of any cognitive changes. Comparisons were adjusted for age, sex and baseline performance, and showed a steeper decline of category fluency score in slow walkers (fast walkers +0.04 (-1.49 to1.56) compared with -0.89 (-2.15 to 0.38), p=0.049) with a moderate effect size.

In frail or prefrail older adults with diabetes, we observed a decline in category fluency in those with low gait speed.