Mind-motor Exercise in Older Adults With Type 2 Diabetes and Self-reported Cognitive Complaints

Dementia has been identified as a global health concern because of the increase in incidence globally. Regardless of whether individuals with self-reported cognitive complaints (CCs) have objective impairment, they are at increased risk for cognitive decline, and they are comparable to those with early mild cognitive impairment (MCI) for brain atrophy and increased risk of progression towards Alzheimer's disease (AD). People who express being worried about their memory or cognition show a further increased risk of cognitive decline. If prevention programs could delay the onset of dementia even in part of the at-risk population, this could decrease disease prevalence significantly. The risk of cognitive impairment or dementia is increased in type 2 diabetes (T2D) and T2D accelerates the progression from MCI to dementia.

The proposed mind-motor intervention for the prevention of cognitive decline in T2D is called square stepping exercise (SSE). The SSE program was developed by Shigematsu and Okura (2005) and can be best described as a visuospatial working memory task with a stepping response. There are more than 200 patterns developed for this program that progress from simple to advanced stepping patterns. The primary focus of Shigematsu and colleagues' research has been to examine the impact of SSE on fall risk factors and mobility in older adults. Within their research they have found that SSE improves lower extremity functional fitness, reduces fall risk, and improves overall fitness in older adults when compared to walking or strength and balance training. In combination with Dr. Shigematsu's research in Japan in healthy older adults, the investigators are aiming to provide a significant evidence base for SSE internationally and within varied populations, including older adults with subjective cognitive complaints and with different chronic diseases. In collaboration with Dr. Shigematsu, the investigators have executed SSE studies at the Canadian Centre for Activity and Aging and currently are running a study in the community in Woodstock, ON. Preliminary evidence has shown that over a 6-month exercise plus mind-motor training period, participants improved in global cognitive functioning, verbal learning and memory, and verbal fluency, when compared to an exercise control group. Most recently, Shigematsu and colleagues have found the SSE program to improve memory and executive function in a 6-month pilot study.

The overarching goal of the investigators is healthy aging; research goals aim to evaluate intervention tools in the prevention of cognitive decline at one of the earliest markers of cognitive decline, which is a subjective complaint. As well, goals of the intervention strategies are to maintain mobility and balance with advancing age and chronic disease. The T2D population is at increased risk of decline and the added component of self-management of diabetes and insulin treatment makes it crucial to maintain adequate cognition and independence in this population.

Study Design: This study will be a 24-week Proof-of-Concept randomized controlled trial (1:1 allocation) whereby consenting and eligible participants will be randomized to either: 1) the SSE intervention group or 2) a usual-care, wait-list control group. Participants will be recruited from the St. Joseph's Primary Care Diabetes Support Program (SJHC- PCDSP) and the study intervention will be conducted at a community location in London, Ontario. This will be a single blinded study. All assessments will be done pre-intervention (V0) and post-intervention (V2), with interim assessments after 12-weeks (V1) (with the exception of sensorimotor). Assessments will take place at SJHC-PCDSP and Western University. One assessment will be done online either at the participant's home or at SJHC-PCDSP (solely completed by the participant)(i.e. Cambridge Brain Sciences). We will use blocked randomization and thus, participants will begin and complete the trial within waves.

Participants: All participants will be required to self-report a cognitive complaint; once eligibility is determined, participants will then be asked further questions about their cognition. Participants will undergo a number of measurements at baseline, which will be used to describe the study sample. These measures include: i) baseline cognition: Montreal Cognitive Assessment (MoCA) and the Clock Drawing Test; ii) baseline fitness: Step test iii) Anthropometric measures: weight, height, waist circumference; iv) history of physical and mental activities: Leisure Activities questionnaire v) clinic blood work values HbA1c, creatine (eGFR), and lipid assessment obtained from clinic electronic medical records (EMR) and vi) demographic information. Current medications, blood pressure and patient medical history will also be obtained from EMRs.