Fear of Falling and Balance Confidence in Older Adults with Diabetes Mellitus

Several determinants of fear of falling (FoF) and low balance confidence overlap with the consequences/complications of diabetes mellitus (DM). FoF is strongly associated with low balance confidence, and balance confidence mediates the relationship between FoF and balance and physical function. The purpose of this thesis was two-fold: (1) to examine the prevalence, severity and determinants of FoF in older adults (aged≥65) with DM, and (2) to evaluate the validity of the short version of the Activities-specific Balance Confidence scale (ABC-6) and its association with balance and postural control in older adults with DM. Three separate studies were conducted of older adults with DM (DM-group) and without DM (noDM-group). Study I revealed that although FoF prevalence adjusted for age and sex was not different between-groups, the DM-group had 8.8% fewer participants in the low and 8.4% more in the high Falls-Efficacy Scale International categories when compared to the noDM-group. Higher FoF severity in the DM-group was associated with poor physical performance, being female, fall history and clinical depressive symptoms. Study II provided evidence of convergent, discriminant and concurrent validity of the ABC-6 for use in older adults with DM with and without diabetic peripheral neuropathy (DPN). Notably, the ABC-6 was more sensitive in detecting subtle differences in balance confidence between the DM-group and noDM-group when compared to the original ABC scale (ABC-16), and can be administered in less time. Study III explored balance confidence (ABC-6) and its association with balance and postural control in older adults with DM. Subtle differences in axial segmental control (i.e., lower trunk roll velocity and higher head-trunk correlations) while walking and lower balance confidence were apparent in the DM-group, even in the absence of DPN, when compared to the noDM-group. Balance confidence partially explained the variance in head-trunk stiffening between-groups, and consequently low balance confidence in older adults with DM may contribute to the dependence on postural control strategies that are normally only utilized in high-risk situations. Findings from this thesis will help to guide the development of protocols for screening and intervention recommendations of patient education and targeted rehabilitation programs for older adults with DM.

Redefining Attitude Importance: The Possible Existence of Associative and Subjective Types of Importance Under a Global Definition

Traditionally, importance has been measured using subjective measures. The present thesis explores the possibility of a second type of importance, designated as “associative importance”. A new measure, the IIAT, was designed to capture the strength of association between an object and the attribute of importance. This thesis then evaluated the validity of the IIAT via an intervention paradigm in 2 studies, and by using the measure to predict a memory outcome in 2 other studies. Subjective measures of importance were also included in these studies and correlations between subjective measures and IIAT results were examined. Across all 4 studies, subjective-objective correlations were weak to modest and non-significant. The intervention studies provided promising evidence that interventions do affect associative importance as measured by the IIAT. The prediction studies provided somewhat mixed, but encouraging evidence that the IIAT may be able to predict memory performance. Notably, subjective measures were not able to predict memory performance at all, whereas the IIAT was able to predict some memory indices. Overall, there is some evidence supporting the existence of an associative importance construct, and that the IIAT provides valid results that are nonetheless different from that of subjective measures of attitude importance.