Headaches significantly impact patients' quality of life, with tension-type headaches and migraines being among the most prevalent types. There is growing evidence suggesting that blood pressure regulation and baroreceptor activity play a role in headache pathophysiology. Carotid sinus massage (CSM), particularly when combined with the modified Trendelenburg position, may modulate autonomic nervous system activity to relieve headache symptoms.

An initial open-label pilot study (n = 17) was completed, and the results were published in a preprint server for health sciences, the Medical Research Archive (medRxiv), demonstrating the feasibility, safety, and promising preliminary efficacy of CSM+T. Based on these findings, a follow-up randomized, sham-controlled, parallel-arm trial will further evaluate the efficacy of the treatment.

This protocol includes two study phases:

1. Pilot Phase (Completed): A single-arm, open-label pilot study was conducted in 17 participants to assess the feasibility and safety of CSM+T for the relief of headaches. Results have been published in medRxiv and support continued investigation.
2. Parallel-Arm Phase (Planned): A randomized, sham-controlled, parallel-arm clinical trial will now be implemented to evaluate efficacy. This phase will enroll 18 participants (9 per arm) to detect a clinically meaningful difference in headache relief with 80% power (α = 0.05, two-sided), accounting for potential attrition.

INCLUSION CRITERIA:

• Participants must be at least 16 years of age.

• Must have a diagnosis of one of the following, according to the International Classification of Headache Disorders (ICHD-3):

  • Migraine
  • Tension-type headache
  • Mixed headache

• The headache episode must have started within the past 24 hours.

EXCLUSION CRITERIA:

• Any contraindication to carotid sinus massage, including:

  • Carotid bruits
  • Recent myocardial infarction
  • History of stroke
  • Known or suspected carotid artery stenosis

• Any contraindication to the Trendelenburg position, including:

  • Increased intracranial pressure
  • Respiratory distress
  • Congestive heart failure
  • History of syncope
  • History of cardiac arrhythmias

De-identified individual participant data (IPD) related to study outcomes will be shared, including pain scores, physiological measurements (such as heart rate, blood pressure, and oxygen saturation), and adverse event reports. Data will be made available upon reasonable request after publication of the primary results.

IPD will be made available beginning 6 months after publication of the primary results and will remain available for a minimum of 5 years thereafter.

Qualified researchers may request access to the data by submitting a data use proposal, which should include a brief description of the study objectives and statistical plan. Requests will be reviewed by the study investigators or a designated data access committee. Data will be shared via secure transfer methods, subject to a data use agreement, to ensure participant confidentiality.

In this single-blinded design, the patients do not know whether they are receiving the real CSM+T or the sham intervention, ensuring unbiased reporting of pain outcomes. However, it is not possible to double-blind (i.e., also blind the healthcare providers) because the clinicians administering CSM+T or the sham procedure must be aware of which maneuver they are performing, making true double-blinding impractical in this hands-on intervention study.