# Sex-related differences in the short and long-term outcome of internal pallidus stimulation for dystonia

## TL;DR

This study found that sex does not significantly affect the outcomes of deep brain stimulation for dystonia, with similar improvements in both men and women.

## Contribution

The study provides evidence that sex is not a critical factor in the efficacy of internal pallidus stimulation for dystonia.

## Key findings

- Male and female patients showed comparable motor improvements after GPi-DBS.
- Females initially used less electrical energy but increased it significantly during follow-up.
- The position of optimal stimulation did not differ significantly between sexes.

## Abstract

The importance of sex as a determinant of Globus pallidus internus deep brain stimulation (GPi-DBS) outcome in adults with dystonia remains uncertain. We investigated whether sex is a determinant of the efficacy and safety of GPi-DBS in dystonia.

In this double-center, retrospective cohort study, we followed patients with idiopathic, inherited, or secondary dystonia for at least 12 months after surgery. Dystonia was assessed using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). Adverse events were recorded.

Fifty-six consecutive patients (22 M/34F) were studied. GPi-DBS led to comparable improvements in both sexes. Male patients showed a motor improvement of 62.6 ± 42.4% at 1 year and 53.9 ± 20.9% at the last follow-up (8.6 ± 3.3 years), while female patients showed a motor improvement of 60.5%±29.0% at 1 year and 48.6 ± 28.3% at the last follow-up (at 7.1 ± 4.2 years). Improvement in disability and adverse events were comparable between the two groups. At the first reglage, females showed lower electrical energy delivery, which increased significantly during follow-up. The position of the optimal stimulation center did not differ significantly between the two groups.

Our study suggests that the overall motor outcomes and safety profiles were similar across sexes, indicating that factors such as age at implant, precision of lead positioning, and severity of dystonia may be more critical determinants of efficacy than sex itself.

The online version contains supplementary material available at 10.1007/s10072-025-08733-3.