2024 American Academy of Neurology Abstract Website

Objective:

Describe real-world incidence of dysphagia and other comorbidities in adults with cervical dystonia (CD) treated and not treated with botulinum neurotoxin (BoNT).

Background:

Real-world studies can provide data in more heterogenous populations than clinical trials (13%-19%).

Design/Methods:

This retrospective cohort study used longitudinal patient-level data from the Optum Market Clarity database and included >700 US hospitals and >7000 US clinics. Patients aged ≥18y with ≥2 ICD-10 CD diagnoses ≥30d apart during the study (1/1/2017-9/30/2021) and ≥180d of continuous health plan enrollment prior to cohort entry date (CED; first CD diagnosis coding during study) were included. Cohort 1: all patients with CD. Cohorts 2 and 3 (mutually exclusive): BoNT-exposed (date of BoNT injection in the neck area +16wk, excluding patients who received BoNT 12wk before CED) and BoNT-unexposed CD patients, respectively.

Results:

Cohort 1 included 81,884 CD patients (mean age 54y, 68% female, 77% White), 19,244 in Cohort 2, and 61,154 in Cohort 3. Relative to Cohort 3, Cohort 2 had more older patients with comorbidities including chronic migraine and other neurologic disorders, but fewer males and African Americans. In Cohort 2, CD patients with continuous enrollment for ≥12mo (73%) and ≥24mo (53%) received BoNT for a mean±SD of 3.0±1.6 and 4.7±2.9 injection cycles, respectively. Reported dysphagia rates during the study were 13.7% (Cohort 1), 16.3% (Cohort 2), and 12.1% (Cohort 3). Across cohorts, incident dysphagia was more prevalent in patients with other dystonias, neurologic conditions, or baseline dysphagia. Patients diagnosed with dysphagia during follow-up were older with higher baseline comorbidity rates.

Conclusions:

Real-world, heterogenous patients with CD may have occurrence of dysphagia whether or not exposed to BoNT and which may be related to risk factors such as baseline dysphagia and other comorbidities. Cohort 2 may have included a higher proportion of older patients with comorbidities, and likely more severe disease, than Cohort 3.