84: Balance in older Tasmanians

Does balance vary with season in older Tasmanians and what are the influences and effects? ($18,980) – Marie-Louise Bird

This project aims to measure variations in postural balance in older adults during the year. Rates of falling and of non-vertebral factures are seasonally dependent with the highest incidence occurring 6-12 weeks after the shortest day of the year. The mechanisms for changes seen in fracture incidence are related to both bone and neuromuscular health. Hours of daylight influence both an individual’s vitamin D levels and their ability to maintain physical activity. Postural balance relies on strength in the lower limbs and both levels of activity and vitamin D impact on postural sway. Descriptive, observational cohort study with analysis of postural balance at different times of the year and of association between potential exposure variables and outcome variables.

Recruitment of 100 healthy independently mobile community dwelling adults over the age of 60 living in Tasmania will be undertaken. Participants who take prescribed vitamin D supplementation will be excluded from this study, as well as those with acute medical illness or kidney disease. Particpants will attend for testing five times over a one year period. This poject will mesure plasma levels of vitamin D, expoosure to sunlight and dietary levels of vitamin. D. Demographic data and medication use will also be recorded. Activity levels and prospective fall rate and type will be recorded using a diary system. Lower limb strength will be measured using a dynamometer. A force platform will be used to measure postural sway and two clinical measures of balance and lower limb function (TUG and 4 square step test) will be used.

The project aims to determine (a) if there are seasonal variations in balance which may contribute to the increased fall rates that have been observed during winter and (b) the association of physical activity and vitamin D levels to balance measurements.