|
1. No evidence that HBO improves outcome in cluster headache compared to a sham therapy. |
Citation/s:
1. AIM. Nilsson Remahl, R. Ansjon, F. Lind, E. Waldenlind. Hyperbaric oxygen
treatment of active cluster headache: a double-blind placebo-controlled
cross-over study. Cephalalgia 2002; 22:730-739.
Lead author's fax: +46 8774 48 22
Three-part Clinical Question: For patients with cluster headache
does the application of HBO, compared to a standard treatment with normobaric
oxygen during a cluster, result in prevention or shortening of headache
clusters?
Search Terms: cluster headache.
The Study:
Double-blinded randomised cross-over trial with intention-to-treat.
The Study Patients: Patients with chronic or episodic CH, with at least
six headaches during the week prior to enrolment, and an expected remaining CH
period of > 4 weeks. Excluded if using prophylactic treatment.
Control group (N = 12; 12 analysed): Sham treatment using 10% oxygen
for 70 minutes at 2.5 ATA for two sessions 24 hours apart. Rescue simple
analgesia if required.
Experimental group (N = 10; 10 analysed): HBO treatment with 100%
oxygen as above.
The Evidence:
|
Outcome |
Time to Outcome |
Sham rate |
HBO rate |
Relative risk reduction |
Absolute risk reduction |
NNT |
|
>50%
reduction in HI. |
1
week |
0.38 |
0.36 |
-5% |
-0.02 |
56 |
|
95% Confidence Intervals: |
-97% to 87% |
-0.36 to 0.33 |
NNT = 3 to INF NNH = 3 to INF |
|||
Comments:
1. Small study with low power to detect important differences between groups.
2. Patients were divided into chronic and episodic groups after primary
analysis.
3. 2 patients had remission of headaches for >1 year after sham treatment
and were therefore not crossed over.
4. 5 patients required mild to moderate attacks during sham treatment, none
during HBO.
5. Authors measured a number of serum markers of vasoactivation, but reported
no significant differences.
6. Results poorly reported with apparent 'post-hoc' comparisons.
Appraised by: Jetske van Breda and Mike Bennett, Prince of Wales Hospital;
Monday, December 15, 2003
Email: Jetskevanbreda@hotmail.com
Kill or Update By: December 2005