Date of Award


Document Type


Degree Name

Doctor of Psychology (PsyD)



First Advisor

David J. LaPorte, Ph.D.

Second Advisor

Michael D. Franzen

Third Advisor

Dasen Luo, Ph.D.


The current study investigated the effects of hyperglycemia, hypertension, and hypercholesterolemia on the severity of sequelae related to traumatic brain injury. Existing data of 209 participants was utilized from an urban hospital, which included neuropsychological evaluations following traumatic brain injury. Specific areas examined included measures of executive functioning, both immediate and delayed memory, and learning. Each participant was placed into a group based on the number of documented diagnoses (hyperglycemia, hypercholesterolemia, and hypertension). The control group consisted of patients that did not carry a record of these health risks. Each of these groups was further stratified according to age. An interaction between the variables of health risk factors and neuropsychological assessment results was predicted specified by decreasing standard scores with the increase in number of health risk factors. Furthermore, age was hypothesized to be a main effect, with the prediction of a decline in scores as age increases. However, results of a factorial MANOVA indicate that age had no effect on performance and scores actually increased (improved) in the older age group. Of the four measures used to assess neuropsychological performance, the increase in performance from the younger to older group was significant for the executive functioning measure. There was also a trend found in all measures except for learning, demonstrated by a decrease in performance as the number of health risks in a participant increased (executive functioning [á=.01, p=.010, 1-â= .805]; immediate [á=.05, p=.013, 1-â= .794]; delayed memory [á=.01, p=.002, 1-â= .914]). A discriminant function analysis and Tukey's HSD post hoc test were implemented to explore significant findings. Finally, the implications of these results as well as limitations to the current study are discussed.