Access to movement disorders care and advanced surgical therapies in a tertiary care center

Background: Barriers in access to Movement Disorders specialty care may explain sociodemographic differences in the utilization of deep brain stimulation (DBS) surgery for medically refractory Parkinson's disease (PD) and essential tremor (ET). Methods: This retrospective chart review used electronic medical records between 2012 and 2022 from a single tertiary movement disorders center to characterize DBS surgery patterns among a diverse group of movement disorders patients. Patients were diagnosed with PD, ET, or unspecified tremor aged 18 or older. Patient characteristics were summarized and compared between those who did and did not undergo DBS implantation using chi-square tests for categorical variables and Wilcoxon rank-sum tests for continuous variables. Multivariable regression model was used to identify associations between clinical and sociodemographic covariates and DBS surgery. Results: Of 3,286 PD/ET patients between 2012 and 2022, 12.1% underwent DBS surgery. Those who underwent surgery were younger and had fewer medical comorbidities. Within the surgical group, there were higher proportions of Hispanic ethnicity, non-English language preference, Medicare or Medi-Cal insurance, and residence in neighborhoods with lower socioeconomic status (SES). On multivariable logistic regression analysis, MediCal insurance and low neighborhood SES were associated with higher odds of surgery. Conversely, younger age at initial visit, single marital status, and Asian race were associated with lower odds of surgery. Conclusion: Sociodemographic variables associated with higher odds of receiving DBS surgery included low SES and Medi-Cal insurance. This may reflect a referral bias suggestive of better access to our center for DBS surgery than for routine movement disorders care for those from low SES and Medi-Cal. Future studies within our center will focus on quantitative and qualitative evaluation of referral processes for the treatment of advanced movement disorders in order to better understand and improve accessibility of these therapies to all patients in our health system and nationally.