Wiles
There was no evidence of subjective or functional improvement associated with the administration of hyperbaric oxygen to patients with chronic progressive multiple sclerosis.
Clinical Bottom Line: 1. No evidence of significant functional improvement with the addition of hyperbaric oxygenation to the treatment of multiple sclerosis.
Appraised by:Mike Bennett, Dept of Diving and Hyperbaric Medicine, Prince of Wales Hospital Sydney; Monday, 8 March 1999
Clinical Scenario: A patient with chronic progressive multiple sclerosis presented for treatment. We wondered if the addition of hyperbaric oxygen would improve function or prevent deterioration. Three-part Question: In patients with chronic progressive multiple sclerosis, does the addition of hyperbaric oxygen therapy to the usual on-going measures, result in any addition benefit in terms of functional improvement or subjective awareness of improvement? Search Terms: Hyperbaric oxygenation, multiple sclerosis
The Study: Double-blinded concealed randomised controlled trial with intention-to-treat. Known chronic progressive multiple sclerosis with no acute relapse in the past year and no steroids or immunosuppression in the past six months. Control group (N = 44; 44 analysed): Twenty sham hyperbaric oxygen sessions, 5 times per week for 5 weeks, by the administration of air at 1.1ATA. Experimental group (N = 44; 44 analysed): Twenty hyperbaric oxygen sessions at 2ATA on 100% oxygen by the same treatment schedule as above.
The Evidence:
| Outcome (Patient assessment of improvement) | Time to Outcome | Air group | HBO group | Relative risk reduction | Absolute risk reduction | NNT |
| Bladder symptoms | 1 month | 0.286 | 0.310 | -8% | -0.024 | -42 |
| 95% CI: | -77% to 60% | -0.220 to 0.172 | NNT6 to INF NNH5 to INF | |||
| Walking | 1 month | 0.333 | 0.286 | 14% | 0.047 | 21 |
| 95% CI: | -45% to 73% | -0.150 to 0.244 | NNT4 to INF NNH7 to INF |
Non-Event Outcomes Time to outcome Air group HBO group P-value Patient assessment of change compared to pre-trial 1 month +0.7 +10.1 >0.05
(mm) on a scale 0-100mm Neurologist assessment 1 month -1.9 -0.2 >0.05 (similar to above)
Timed walk over 50m (sec) 1 month 2.9 -2.0 >0.05
Change in Kurtzke disability score (0-10) 1 month +0.01 +0.05 >0.05
Comments: 1. Good methodological study with 90% power to detect a difference in improvement of disability score of 1.0 points. 2. The design planned for further assessment at 3 months, 6 months and 1 year but the results do not appear to have been published. 3. Data was analysed by multiple regression to account for any treatment centre bias and 5 patients who did not tolerate treatment were analysed by intention to do so.
Expiry date: January 2015 References: 1. Wiles CM, Clarke CR, Irwin HP, Edgar EF, Swan AV. Hyperbaric oxygen in multiple sclerosis: a double blind trial. British Medical Journal 1986; 292:367-371.
