Document Type

Capstone Experience

Graduation Date


Degree Name

Master of Public Health



First Committee Member

Tricia D. LeVan

Second Committee Member

Lynette M. Smith

Third Committee Member

Ming Qu


Background: Parkinson’s disease (PD) patients are at higher risk of traumatic brain injury (TBI) due to disease characteristics like tremor, bradykinesia, and impaired balance. Most of the studies that have been done in the United States to investigate the incident rate and causes of TBI among PD patients have mainly focused on falls, while none of these studies have thoroughly addressed all causes of TBI among the PD population or have used a population-based database. Our study aims to investigate the incidence rate, types, and external causes of TBI stratified by age of PD diagnosis using a population-based database from Nebraska. The outcomes of this study will provide valuable insights regarding the cause of TBI episodes among the PD population.

Methods: We conducted a retrospective study comprising of patients diagnosed with PD between 2008-2014. A statewide linkage was done between Nebraska PD Registry data and the Nebraska hospital discharge database (HDD). 4037 PD patients were enrolled in the study. PD patients were grouped based on their age of diagnosis into four categories; 30-59 years, 60-69 years, 70-79 years, and ≥80 years. The overall incidence rate and age-specific incidence rate of TBI in the Nebraska PD population was calculated. A chi-square test and multivariable logistic regression model was used to determine the age-specific difference of TBI among those with PD. Frequencies were used to describe the subtypes and external causes of TBI among the four age groups of PD patients.

Results: Between 2008 and 2014, 216 (5.35%) PD patients and 43,530 (4.1%) non-PD residents sustained TBI in Nebraska. The age-adjusted incidence rate of TBI was eight times higher in the PD subject than the general population (4,109 per 100,000 vs. 513 per 100,000). Among PD subjects, logistic regression analysis revealed that age of diagnosis and disease duration were significantly associated with TBI, (p=0.0008 and p=0.0079, respectively). Among PD patients with TBI, unspecified head injury was the most frequent type of TBI (68.5%) followed by concussion (27.5%). Falls accounted for 88.9% of TBI incidents among the PD population.

Conclusion: PD patients experienced more TBI events than the general population. After adjusting for age, gender, disease duration, and location of residence, age and disease duration were significantly associated with TBI among the PD population. The analysis also revealed that unspecified head injury and concussion were the most common types of TBI in both PD and the general population. Further analysis showed that falls accounted for the majority of TBI episodes among PD and the general population. Nonetheless, PD patients suffered from a higher rate of falls compared to general population.