Somatic points for cough and urge to cough in chronic coughers

Recently, a group of researchers documented a case of a patient with chronic cough who reported an urge to cough (UTC) or coughing triggered by light pressure on the sternocleidomastoid muscle and sternum, and on the lower cervical or first dorsal vertebrae, as well as by pressure on the jugular notch and neck movements.
Based on this, the researchers conducted a clinical investigation of this coughing pattern in both chronic coughers and controls.

Methods

  • The study included 58 adult outpatients with consecutive chronic cough and 34 healthy controls.
  • The researchers attempted to trigger coughing and/or the UTC feeling by applying finger pressure to specific spots on the chest and neck, as well as by having the patient move their neck fully up and down.
  • An area on the upper trunk or neck that caused a UTC feeling or visible coughing in response to mechanical stimulation was referred to as a “somatic point for cough” (SPC).
  • Participants with at least one SPC were considered SPC+ while those with no identifiable SPC were classified as SPC-.
  • A calibrated force sensing resistor (Ohmite FSR03, Warrenville, IL) attached to the tip of the investigator’s first finger was used to measure the minimum pressure required to trigger UTC or coughing.
  • Patients rated the intensity of the UTC experienced by means of a visual 0–9 scale (VAS).

Results

Controls

  • No UTC with any mechanical action
  • Light pain in 9 subjects with pressure on the sternal bone

Chronic cough patients

  • Pain in 14 patients with sternal pressure
  • Similar cough scores and pain sensation prevalence in SPC+ and SPC- subgroups
  • Most frequently identified SPCs: Jugular notch and neck flexion/extension
  • Infrequently identified SPCs: Sternum and spine
  • Responses were abolished by cooling with dry ice

The significant proportion of patients with chronic cough who also present with SPC suggests that this symptom plays a significant role in the development and continuation of the condition. The reason why only specific mechanical stimulation of somatic areas can trigger UTC or cough remains unknown.

Reference:
Mannini C, Bernacchi G, Bonti V, et al. Somatic points for cough and urge to cough in chronic coughers. Respir Med. 2022;200:106929.