A double-blind trial of hyperbaric oxygen in the treatment of multiple sclerosis. Hyperbaric oxygen therapy in chronic stable multiple sclerosis: double-blind study. Hyperbaric-oxygen treatment of multiple sclerosis. A randomized, placebo-controlled, double-blind study. Hyperbaric oxygen and multiple sclerosis: final results of a placebo-controlled, double-blind trial. [Ineffectiveness of hyperbaric oxygen therapy in multiple sclerosis. A randomized placebo-controlled double-blind study]. Hyperbaric oxygen in multiple sclerosis: a double blind trial. [Double-blind treatment of 49 cases of chronic multiple sclerosis using hyperbaric oxygen]. Hyperbaric oxygen in chronic progressive multiple sclerosis: visual evoked potentials and clinical effects.
A randomized double-blind trial of hyperbaric oxygen (2 atmospheres absolute for 20 sessions of 90 minutes, over a period of one month) demonstrated no advantage over a placebo gas mixture in the treatment of multiple sclerosis. Of 41 patients completing the trial, 21 had been treated with oxygen, eight of whom reported improvement (two confirmed objectively). Of 20 patients in the placebo group, seven claimed improvement (four confirmed objectively). Even when patients with mild disease were considered separately, or when functional systems were assessed individually, no benefit could be shown to result from hyperbaric oxygen therapy. We carried out a randomized, double-blind, placebo-controlled trial of hyperbaric oxygen therapy (HBO) in patients with chronic stable MS. Eighty-two patients were treated in a multiplace hyperbaric chamber with gas supplied by mask. Forty-one patients received 20 consecutive daily treatments of 100% O2 followed by 7 "booster" treatments in the next 6 months; 41 control patients received "air" (12.5% O2 at 1.75 atmospheres absolute). There was no significant difference in treatment and control groups in the Extended Kurtzke Disability scores, Kurtzke Functional scores, magnetic resonance imaging, or evoked potentials after the initial 20 treatments or after the boosters. HBO is not effective in treating chronic stable MS. Several uncontrolled studies have suggested a beneficial effect of hyperbaric oxygen on multiple sclerosis. We studied 40 patients with advanced chronic multiple sclerosis who were randomly divided into two matching groups. The experimental group received pure oxygen, and the placebo group received a mixture of 10 per cent oxygen and 90 per cent nitrogen; both groups were treated at a pressure of 2 atmospheres absolute for 90 minutes once daily, for a total of 20 exposures. Objective improvement occurred in 12 of 17 patients treated with hyperbaric oxygen and in 1 of 20 patients treated with placebo (P less than 0.0001). Improvement was transient in seven of the patients treated with oxygen and long-lasting in five. Those with less severe forms of the disease had a more favorable and lasting response. At one year of follow-up, deterioration was noticed in 2 patients (12 per cent) in the oxygen group, neither of whom had had an initial response, and in 11 patients (55 per cent) in the placebo group, one of whom had had a positive initial response (P less than 0.0008). Minor ear problems and reversible myopia were the only side effects observed. These preliminary results suggest a positive, though transient, effect of hyperbaric oxygen on advanced multiple sclerosis, warranting further study. This therapy cannot be generally recommended without longer follow-up periods and additional confirmatory experience. The long term results are reported of a trial involving 120 patients with chronic multiple sclerosis who were randomised to receive either 100% oxygen at 2 atmospheres absolute (ATA) for 90 minutes daily for 20 sessions or placebo therapy with air using a simulated compression procedure. The previous finding of subjective improvement in bowel/bladder function at the end of treatment was not confirmed by objective urodynamic assessment. The treatment did not alter disease progression as measured by the Kurtzke disability status scale nor did it alter the rate of acute relapse. There was less deterioration in cerebellar function at one year in the treated patients as measured by the Kurtzke functional systems scale. No other differences were found between the two groups. Psychometric tests and measurements of lymphocyte sub-populations showed no treatment related effects. Evoked potential studies showed no improvements but there was a significant reduction in amplitude of the visual evoked potential in the treated patients at the end of therapy. This might indicate a reversible degree of retinal damage induced by oxygen toxicity. Seventeen patients with definite and progressive multiple sclerosis entered a double-blind randomized placebo-controlled therapeutic trial of hyperbaric oxygen (HBO). Exposure in monoplace chamber was 90 minutes long each time, 5 days a week, for 4 weeks. The treatment and placebo groups received 100% oxygen at 1.5 bar constant pressure or normal air at 0.1-0.2 bar, respectively. The clinical status of the patients in both groups were compared until one year after treatment. There was no benefit of HBO versus placebo according to the Kurtzke disability status scale. A lesser proportion of patients with deterioration of bowel/bladder function 12 months after therapy was the only benefit of HBO versus placebo according to Kurtzke functional systems scales. On the whole however, HBO is useless in the management of progressive forms of multiple sclerosis. Eighty four patients with multiple sclerosis were treated in monoplace chambers with either hyperbaric oxygen at 2 atmospheres absolute or placebo. Comprehensive double blind assessment was carried out before, immediately after, and one month after treatment. There was no clinically important or significant benefit in any of the four major criteria of outcome--namely, the patient's subjective opinion, the examiner's opinion, the score on the Kurtzke disability status scale, or the time taken to walk 50 m. Out of 40 other clinical variables assessed, two (the sensory scale and timed writing with the left hand) showed a significant improvement without any subjective clinical correlate or change in any of seven other tests of left hand function. No group of symptoms was perceived by the patients as having improved more after treatment with hyperbaric oxygen than placebo. It is concluded that there is no basis for recommending hyperbaric oxygen in the treatment of multiple sclerosis. Forty nine patients with a chronic form of multiple sclerosis (MS) [progressive or stable] were treated with hyperbaric oxygen (HO) in a double blind trial. Patients were divided in three groups: the first group (group I) received a course of 2.3 ATA HO with diazepam (5 mg); the second group (group II) received a course of 2 ATA HO; the third group (group III) was the control group. Each patient breathed an adapted gaseous mixture in high pressure. Each patient received 20 sessions of this procedure during 4 weeks. Patients were evaluated with clinical, neurophysiological and immunological parameters. Clinical examination consisted in the evaluation of the Kurtzke's Disability Status Scale (DSS) and Functional Status Scale (FSS). This evaluation was done in the week before the procedure, the week following the treatment, then in the third and sixth month. The neurophysiological study was a comparative analysis from the variations of visual, somesthesic and brain stem auditory potentials. The immunological study was the analysis of the lymphocyte populations (OKT4/OKT8 ratio). Each examination was carried out the week before, then the week following the procedure. We found no amelioration into three groups. Subjectively, some patients thought to be better, but this was true in the two treated groups (I, II) and in the control group (III). There was not an FSS significant variation. We also found no significant variation of evoked potentials and OKT4/OKT8 ratio. We observed some incidental effects of the treatment, particularly in group I, in which patients were treated with a higher pressure.(ABSTRACT TRUNCATED AT 250 WORDS) The effects of hyperbaric oxygen at a pressure of two atmospheres absolute were studied in a group of patients with chronic progressive multiple sclerosis. A slight but statistically insignificant shortening of the visual evoked potential latencies was seen after treatment with hyperbaric oxygen as compared with placebo treatment. The treatment did not appreciably halt the progression of the disease and deferioration occurred more often among the patients in the treatment group than in the control group.
We found no consistent evidence to confirm a beneficial effect of hyperbaric oxygen therapy for the treatment of multiple sclerosis and do not believe routine use is justified. The small number of analyses suggestive of benefit are isolated, difficult to ascribe with biological plausibility and would need to be confirmed in future well-designed trials. Such trials are not, in our view, justified by this review.