Examine sex differences in referral patterns and characteristics of patients with essential tremor (ET) evaluated for deep brain stimulation (DBS) at a tertiary center

DBS has been FDA-approved for medically-refractory ET since 1997. Despite an equal proportion of men and women with ET at the University of Colorado and similar reports worldwide, there is a disproportionate number of men who undergo DBS compared to women. There is no suggestion in the literature that women with ET are less likely to benefit from DBS, nor is there evidence that men experience more severe tremor.

We conducted a retrospective analysis of patients with ET that were referred for DBS evaluation at the University of Colorado from January 1, 2011 – December 31, 2018. The primary outcome was the proportion of women referred for DBS compared to men. We also examined differences in the proportion of women and men who were approved for surgery, proportion of those who declined, and select patient characteristics. Analyses were conducted using Chi-square tests for categorical variables and t-tests or Mann-Whitney U-tests as appropriate for continuous variables.

Sixty-eight patients were included in this analysis. Twenty were women (29%) and 48 were men (71%), which is significantly different than expected given the equal prevalence of ET (p=0.01). Forty-eight of 68 patients (71%) were approved for surgery. There was no difference in the proportion of women and men approved (60% vs. 75%; p=0.22); however, of those approved, women were more likely to decline surgery than men (50% vs 17%; p=0.02). Age at evaluation (p=0.2), decade of onset (p=0.5) and number of medication trials (p=0.7) were all similar between the two groups.

Women with ET were less likely than men to be referred for DBS and to choose to undergo surgery once approved, both factors that contributed to lower utilization.