Document Type
Dissertation
Degree
Doctor of Philosophy (PhD)
Major/Program
Dietetics and Nutrition
First Advisor's Name
Adriana Campa
First Advisor's Committee Title
Committee chair
Second Advisor's Name
Fatma G. Huffman
Second Advisor's Committee Title
Committee member
Third Advisor's Name
Juan P. Liuzzi
Third Advisor's Committee Title
Committee member
Fourth Advisor's Name
Tan Li
Fourth Advisor's Committee Title
Committee member
Fifth Advisor's Name
John E. Lewis
Fifth Advisor's Committee Title
Committee member
Keywords
Vitamin D, elderly, physical performance, cardiometabolic risk
Date of Defense
11-3-2015
Abstract
Examining factors that affect vitamin D status in the fast-growing elderly population of Miami-Dade, Florida, is needed. Vitamin D deficiency in older adults has been linked to correlates of disability, including falls and fractures, and cardiovascular disease. The purpose of this study was to determine the proportion of vitamin D insufficient individuals and their relationship with vitamin D insufficiency in older adults (n=97) living in Miami-Dade. We evaluated the association between vitamin D status and 1) dual task physical performance to understand the link between vitamin D and cognition in the context of mobility; and 2) cardiometabolic risk, measured by galvanic skin response, pulse oximetry, and blood pressure to create a composite score based on autonomic nervous system and endothelial function. Participants completed baseline assessments that included serum levels of vitamin D, anthropometrics, body composition, dual task physical performance and cardiometabolic risk. Surveys to evaluate vitamin D intake, sun exposure, physical activity, and depressive symptoms were completed. Spearman’s correlations, independent t-tests, paired t-tests, repeated measures ANOVAs, and multiple logistic and linear regressions were used to examine the relationship of vitamin D insufficiency (25(OH)D /ml) and sufficiency (25(OH)D ≥30 ng/ml) with determinants of vitamin D status, dual task physical performance variables and cardiometabolic risk scores. Although the proportion of vitamin D insufficient individuals was lower when compared to the prevalance of the general United States elderly population, it was still common in healthy community-dwelling older adults living in Miami-Dade County, especially among Hispanics. Factors that affected skin synthesis (ethnicity, and sun exposure), and bioavailability/metabolism (obesity) were significant predictors of vitamin D status. Vitamin D insufficiency was not significantly correlated with worse dual task physical performance; however, cognitive performance was worse in the vitamin D insufficient group. Our results suggest a relationship of vitamin D insufficiency with executive dysfunction, and support an association with cardiometabolic risk using an innovative electro-sensor complex, possibly by modulating autonomic nervous system activity and vascular function, thus affecting cardiac performance.
Identifier
FIDC000148
Recommended Citation
Lopez, Johanna, "Correlates of Vitamin D Status in Healthy Older Adults Living in Miami-Dade and its Association with Non-Skeletal Outcomes: A Cross-Sectional Study" (2015). FIU Electronic Theses and Dissertations. 2256.
https://digitalcommons.fiu.edu/etd/2256
Included in
Cardiovascular Diseases Commons, Dietetics and Clinical Nutrition Commons, Nutritional and Metabolic Diseases Commons, Physical Therapy Commons
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