Attention Allocation Impacts Postural Control in Patients with Diabetes

Research Objectives: To identify how attention allocation impact postural control between patients with diabetes mellitus (DM) and age-matched healthy adults when engaging in an attention-demand task.

Design: Cross-sectional and observational study

Setting: Hospital and Research Institute Setting

Participants: Data from ten patients with DM (age:59±10, four females) and ten healthy age-matched adults (age: 62±12, seven females) were analyzed. Key inclusion criteria of DM patients included: (1) age ranged from 19 to 79; (2) can stand independently (3) no other neuromuscular conditions that impact the balance.

Interventions: Participants were well-secured with a harness system and instructed to stand still with eyes open: 1) on a force plate, and 2) on a foam pad that mimicked the unstable surface. To re-allocate participants attention, an auditory Stroop test (AST) that consisted of high and low pitch sound was administered concurrently during the trials. Participants were instructed to answer the correct pitch of the sound instead of the heard words.

Main Outcome Measures: Participants’ postural sway (regarding the center of press and its rambling and trembling) was quantified using the linear (root-mean-square) and non-linear analyses (Sample Entropy). The pupil dilation was converted into the Index of Cognitive Activity (ICA). Lastly, the AST correctness was documented (%).

Results: When compared to age-matched healthy adults, DM showed increased center of pressure movement in the anteroposterior direction. When compared to task difficulty within group, DM presented decreased rambling and trembling Sample Entropy in both anteroposterior and mediolateral directions when standing on a unstable surface. Similarly, both DM’s ICA and correctness decreased when standing on a unstable surface.

Conclusions: This study demonstrated that DM re-allocated the attention to postural control while engaging in an attention-demand task by presenting the decreased ICA and AST correctness. While DM’s attention re-allocation represented the strategy adopted to maintain balance in a challenging condition, it is notably that the decreased rambling and trembling Sample Entropy may imply a high predictability and regularity of postural control that differs from the age-matched healthy adults.

Author(s) Disclosures: The authors have nothing to disclose in this study.