Pain Intensity of Cluster Headache worse than Labour Pain: Study

The link between pain and autonomic features of cluster headache is understood mechanistically through the trigeminovascular reflex, though it is not clear if this is a graded response. Links between pain and other features of cluster headache are less well understood. Therefore, researchers of the USA conducted a study to determine the pain intensity of cluster headache through a large survey, by comparing it to other painful disorders. They also investigated the relationship between maximal pain, autonomic, and other clinical symptoms, as well as demographic attributes of cluster headache.

It was an Internet‐based cross‐sectional survey that included questions on cluster headache diagnostic criteria. Researchers included a total of 1604 cluster headache respondents. Respondents were asked to rate a cluster headache attack on the 0–10 numerical rating scale. Additionally, they were asked if they had experienced a list of other painful conditions such as labour pain or nephrolithiasis and asked to rate that as well. Researchers also included demographics, mood scores, and treatment responses in the survey.

Key findings of the study:

Researchers noted that the respondents rated cluster headache as significantly more intense than every other pain condition examined.

♦They noted that the Cluster headache ranked highest pain intensity at 9.7, then labour pain (7.2), pancreatitis (7.0), and nephrolithiasis (6.9).

♦ They also noted that the majority of cluster headache respondents rated a cluster headache attack at maximal or 10.0 pain score by 72.1% of respondents.

♦They observed that those reporting maximal pain were more likely to have cranial autonomic features in comparison with patients who reported less pain, including conjunctival injection or lacrimation (91% versus 85%), eyelid edema (77% versus 66%), forehead/facial sweating (60% versus 49%), fullness in the ear (47% versus 35%), and miosis or ptosis (85% versus 75%).

♦ They reported that respondents with maximal pain also had other statistically significant findings such as:

• more frequent attacks (4.0 ± 2.0 attacks per day vs 3.5 ± 2.0 attacks per day),
• higher Hopelessness Depression Symptom Questionnaire scores (24.5 ± 16.9 vs 21.1 ± 15.2),
• decreased overall effectiveness from calcium channel blockers (on a 5‐point Likert scale), and
• more likely female: 34% versus 24%

The authors concluded, "Cluster headache is an intensely painful disorder, even in the context of other disorders considered intensely painful. Maximal pain intensity is associated with more cranial autonomic features, suggesting a graded response between pain and autonomic features. "

They further added, "Maximal pain intensity is also associated with headache frequency but not duration, suggesting a relationship between pain intensity and mechanisms controlling headache onset, but not between pain intensity and mechanisms controlling headache offset."

For further information:

https://headachejournal.onlinelibrary.wiley.com/doi/10.1111/head.14021