Neiman
Hyperbaric oxygen was not associated with improvement in chronic progressive multiple sclerosis.
Clinical Bottom Line: 1. Hyperbaric oxygen therapy was not associated with any significant improvement in clinical outcome or visual evoked potential latency.
Appraised by: Mike Bennett, Dept of Diving and Hyperbaric Medicine, Prince of Wales Hospital Sydney; Monday, 25 January, 1999
Clinical Scenario: A patient with chronic progressive multiple sclerosis. Three-part Question: In patients with multiple sclerosis, does the addition of hyperbaric oxygen to the normal treatment regime result in improved functional status or objective evidence of improved myelination. Search Terms: Hyperbaric oxygenation, multiple sclerosis.
The Study: Double-blinded randomised controlled trial with intention-to-treat. Patients with established diagnoses of chronic progressive multiple sclerosis. Control group (N = 12; 9 analysed): All usual care including physical therapy and medications, plus sham hyperbaric treatments breathing air at 1.3ATA for 5 minutes, then slow bleed back to the surface. Total chamber time equal to experimental group. Experimental group (N = 12; 10 analysed): As above plus 100% oxygen at 2ATA for ninety minutes daily for twenty days.
The Evidence:
| Outcome | Time to Outcome | Control rate | HBO rate | Relative risk reduction | Absolute risk reduction | NNT |
| Clinical improvement | 1 week | 0.56 | 0.30 | 46% | 0.26 | 4 |
| 95% CI: | -32% to 100% | -0.18 to 0.69 | NNT1 to INF NNH =6 to INF | |||
| Clinical improvement | 6 months | 0.33 | 0.1 | 70% | 0.23 | 4 |
| 95% CI: | -38% to 100% | -0.13 to 0.59 | NNT2 to INF NNH =8 to INF |
Non-Event Outcomes Control group HBO group P-value Mean change in visual evoked potential (p 100 latency) +1.8 -1.5 <0.05
Comments: 1. 5 patients withdrawn after entry due to treatment intolerance. We have assumed equal rate of withdrawal as these figures have not been given. 2. Small trial with low power to detect clinically important differences. 3. Sham treatment procedure may not have been adequate to maintain blinding of patient.
Expiry date: January 2015 References: 1. Nieman J, Nilsson B, Barr P, Perrins D. Hyperbaric oxygen in chronic progressive multiple sclerosis: visual evoked potentials and clinical effects. Journal of Neurology, Neurosurgery and Psychiatry 1985; 48:497-500.
