An open trial of pyridostigmine in post-poliomyelitis syndrome

Pyridostigmine: Postpoliomyelitis Syndrome

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Treatment for postpolio syndrome

BACKGROUND

Postpolio syndrome (PPS) may affect survivors of paralytic poliomyelitis and is characterised by a complex of neuromuscular symptoms leading to a decline in physical functioning. The effectiveness of pharmacological treatment and rehabilitation management in PPS is not yet established. This is an update of a review first published in 2011.

OBJECTIVES

To systematically review the evidence from randomised and quasi-randomised controlled trials for the effect of any pharmacological or non-pharmacological treatment for PPS compared to placebo, usual care or no treatment. 

SEARCH METHODS

We searched the following databases on 21 July 2014: Cochrane Neuromuscular Disease Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO and CINAHL Plus. We also checked reference lists of all relevant articles, searched the Database of Abstracts of Reviews of Effects (DARE), the Health Technology Assessment (HTA) Database and trial registers and contacted investigators known to be involved in research in this area.

SELECTION CRITERIA

Randomised and quasi-randomised trials of any form of pharmacological or non-pharmacological treatment for people with PPS. The primary outcome was self perceived activity limitations and secondary outcomes were muscle strength, muscle endurance, fatigue, pain and adverse events.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by The Cochrane Collaboration.

MAIN RESULTS

We included 10 pharmacological (modafinil, intravenous immunoglobulin (IVIg), pyridostigmine, lamotrigine, amantadine, prednisone) and three non-pharmacological (muscle strengthening, rehabilitation in a warm climate (that is temperature ± 25°C, dry and sunny) and a cold climate (that is temperature ± 0°C, rainy or snowy), static magnetic fields) studies with a total of 675 participants with PPS in this review. None of the included studies were completely free from any risk of bias, the most prevalent risk of bias being lack of blinding.There was moderate- and low-quality evidence that IVIg has no beneficial effect on activity limitations in the short term and long term, respectively, and inconsistency in the evidence for effectiveness on muscle strength. IVIg caused minor adverse events in a substantial proportion of the participants. Results of one trial provided very low-quality evidence that lamotrigine might be effective in reducing pain and fatigue, resulting in fewer activity limitations without generating adverse events. Data from two single trials suggested that muscle strengthening of thumb muscles (very low-quality evidence) and static magnetic fields (moderate-quality evidence) are safe and beneficial for improving muscle strength and pain, respectively, with unknown effects on activity limitations. Finally, there was evidence varying from very low quality to high quality that modafinil, pyridostigmine, amantadine, prednisone and rehabilitation in a warm or cold climate are not beneficial in PPS.

AUTHORS' CONCLUSIONS

Due to insufficient good-quality data and lack of randomised studies, it was impossible to draw definite conclusions about the effectiveness of interventions for PPS. Results indicated that IVIg, lamotrigine, muscle strengthening exercises and static magnetic fields may be beneficial but need further investigation to clarify whether any real and meaningful effect exists.

Treatment for postpolio syndrome

BACKGROUND

Postpolio syndrome (PPS) may affect survivors of paralytic poliomyelitis and is characterised by a complex of neuromuscular symptoms leading to a decline in physical functioning. The effectiveness of pharmacological treatment and rehabilitation management in PPS is not yet established.

OBJECTIVES

To review systematically the effects of any treatment for PPS compared to placebo, usual care or no treatment.  

SEARCH STRATEGY

We searched the following databases on 1 October 2010: Cochrane Neuromuscular Disease Group Specialized Register, the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, PsycINFO and CINAHL Plus from inception to September 2010.

SELECTION CRITERIA

Randomised and quasi-randomised trials of any form of pharmacological or non-pharmacological treatment for people with PPS. The primary outcome was self-perceived activity limitations and secondary outcomes were muscle strength, muscle endurance, fatigue, pain and adverse events.

DATA COLLECTION AND ANALYSIS

Two authors independently selected eligible studies, assessed risk of bias and extracted data.

MAIN RESULTS

Nine pharmacological (modafinil, intravenous immunoglobulin, pyridostigmine, lamotrigine, amantadine, prednisone) and three non-pharmacological (muscle strengthening, rehabilitation in a warm climate (i.e. temperature ± 25°C, dry and sunny) and a cold climate (i.e. temperature ± 0°C, rainy or snowy), static magnetic fields) studies were included in this review. None of the included studies was completely free from any risk of bias and the most prevalent risk of bias was lack of blinding.There is moderate quality evidence that intravenous immunoglobulin has no beneficial effect on activity limitations and there is inconsistency in the evidence for effectiveness on muscle strength and pain. Results of one trial provide very low quality evidence that lamotrigine might be effective in reducing pain and fatigue, resulting in fewer activity limitations. Data from two single trials suggest that muscle strengthening of thumb muscles (very low quality evidence) and static magnetic fields (moderate quality evidence) are beneficial for improving muscle strength and pain, respectively, with unknown effects on activity limitations. Finally, there is evidence varying from very low quality to high quality that modafinil, pyridostigmine, amantadine, prednisone and rehabilitation in a warm or cold climate are not beneficial in PPS.

AUTHORS' CONCLUSIONS

Due to insufficient good quality data and lack of randomised studies it is impossible to draw definite conclusions on the effectiveness of interventions for PPS. Results indicate that IVIG, lamotrigine, muscle strengthening exercises and static magnetic fields may be beneficial but need further investigation.

A Comparison of Fatigue Scales in Postpoliomyelitis Syndrome

OBJECTIVE

To examine the applicability and validity of traditional fatigue questionnaires in postpoliomyelitis syndrome (PPS) patients with disabling fatigue.

DESIGN

Cross-sectional study. PPS and disabling fatigue were ascertained according to published criteria. Descriptiveness was determined using the McNemar test, and interscale z-score agreement was estimated with Pearson's coefficients.

SETTING

PPS clinic.

PARTICIPANTS

Fifty-six survivors of poliomyelitis: 39 met criteria for PPS, 25 of whom met criteria for disabling fatigue.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The Fatigue Severity Scale (FSS), visual analog scale (VAS) for fatigue, and Fatigue Impact Scale (FIS).

RESULTS

Twenty-four patients scored 50% or higher on the scale range for FSS, compared with 19 patients for VAS for fatigue (P=.042), and 7 patients for FIS (P<.001). Scores for patients with disabling fatigue averaged 81.5%, 62%, and 40.9% of the scale range for FSS, VAS for fatigue, and FIS, respectively. Agreement was moderate between the FSS and VAS for fatigue (r=.45, P=.02), but low between FSS and FIS (r=.29, P=.15), and FIS and VAS for fatigue (r=.20, P=.33). Two sample t tests showed significant differences between those with disabling fatigue and those without, based on FSS scores (t=3.8, P<.001), but not for VAS for fatigue or FIS scores.

CONCLUSIONS

FSS was the most descriptive of the instruments tested. Scores generated by the scales were not interchangeable. Of the 3 scales, FFS seemed to be the most informative for the clinical assessment of fatigue in patients with PPS.

EFNS guideline on diagnosis and management of post-polio syndrome. Report of an EFNS task force

Post-polio syndrome (PPS) is characterized by new or increased muscular weakness, atrophy, muscle pain and fatigue several years after acute polio. The aim of the article is to prepare diagnostic criteria for PPS, and to evaluate the existing evidence for therapeutic interventions. The Medline, EMBASE and ISI databases were searched. Consensus in the group was reached after discussion by e-mail. We recommend Halstead's definition of PPS from 1991 as diagnostic criteria. Supervised, aerobic muscular training, both isokinetic and isometric, is a safe and effective way to prevent further decline for patients with moderate weakness (Level B). Muscular training can also improve muscular fatigue, muscle weakness and pain. Training in a warm climate and non-swimming water exercises are particularly useful (Level B). Respiratory muscle training can improve pulmonary function. Recognition of respiratory impairment and early introduction of non-invasive ventilatory aids prevent or delay further respiratory decline and the need for invasive respiratory aid (Level C). Group training, regular follow-up and patient education are useful for the patients' mental status and well-being. Weight loss, adjustment and introduction of properly fitted assistive devices should be considered (good practice points). A small number of controlled studies of potential-specific treatments for PPS have been completed, but no definitive therapeutic effect has been reported for the agents evaluated (pyridostigmine, corticosteroids, amantadine). Future randomized trials should particularly address the treatment of pain, which is commonly reported by PPS patients. There is also a need for studies evaluating the long-term effects of muscular training.

Aging in polio

For a disease that was "conquered" some 40 years ago with the onset of effective vaccination, the issues of long-term survivors of paralytic polio as they age continue to present challenges to rehabilitation specialists. Aging with polio is a definition of PPS. There are over a million patients with PPS in the United States. Management has to include the appropriate use of exercises, appropriate bracing and support, and, in the case of bulbar and respiratory symptoms, the appropriate use of speech therapy services and ventilatory support. There are no prospective randomized trials studying the treatment of weakness and fatigue in PPS. Pharmacologic interventions are limited at this time but include anticholinergics for muscle weakness and dopaminergic agents or amantadine to control central fatigue. The pathophysiology of aging with polio is consistent with neuronal loss and denervation lying at the heart of the developing disorder, whereas the central nervous system components of the fatigue syndrome may be related to central changes with neuronal loss in the basal ganglia and reticular-activating system. Many of the survivors of the polio epidemics are in their later retirement years, and their needs will increase as they have other disabilities due to natural aging. Sensitivity to some of the special issues in PPS may help to avoid complications. Polio is an active infection in the third world. Although great strides have been made, the disease is endemic in eight nations and is threatening to spread. The lessons learned in treating PPS now will be useful in years to come as these individuals age and manifest PPS in the future.

Postpolio syndrome: a challenge to the health-care system

The practical eradication of poliomyelitis in industrialized countries marks one of the most important achievements of world health policy. Yet, disability induced by polio not only continues to exist among survivors with paralytic sequelae, but may also be further accentuated in a considerable number of affected subjects by the development of postpolio syndrome (PPS). PPS aggravates the motor sequelae already present in such subjects and reduces their functional capacity to the point where it affects their activities of daily living and worsens their quality of life. Inasmuch as development of PPS questions the concept of poliomyelitis as a static disease it poses a challenge not only to health professionals but also to policy-makers tasked with providing the necessary health-care measures and appropriate resources. This study sought to review research on this syndrome and to draw up some recommendations that might prove useful to the health authorities for decision-making purposes.

A comparison of 4 questionnaires to measure fatigue in postpoliomyelitis syndrome

OBJECTIVE

To assess the comparability and reproducibility of 4 questionnaires used to measure fatigue in postpoliomyelitis syndrome (PPS).

DESIGN

Repeated-measures at a 3-week interval.

SETTING

University hospital.

PARTICIPANTS

Convenience sample of 65 patients with PPS.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The Fatigue Severity Scale (FSS), the Nottingham Health Profile (NHP) energy category, the Polio Problem List (PPL) fatigue item, and the Dutch Short Fatigue Questionnaire (SFQ).

RESULTS

Correlations of scores between questionnaires were all significant (P<.01) and ranged from.43 (between the NHP energy category and the PPL fatigue item) to.68 (between the PPL fatigue item and the SFQ). Scores on the second visit, normalized to a 0 to 100 scale, were: FSS, 78+/-15; NHP energy category, 47+/-35; PPL fatigue item, 81+/-17; and SFQ, 65+/-22. Except for the difference between the FSS and the PPL fatigue item, the differences in scores between the questionnaires were significant (P<.01). Scale analysis indicated that all questionnaires measured the same unidimensional construct. The reproducibility of the FSS, the PPL fatigue item, and the SFQ was moderate. The smallest detectable change was 1.5 points for the FSS, 2.0 points for the PPL fatigue item, and 1.9 points for the SFQ.

CONCLUSIONS

Although the questionnaires measure the same fatigue construct in PPS, the results are not interchangeable because the ranges of measurement differ. The NHP energy category, in particular, appeared to have a high detection threshold. The moderate reproducibility of the questionnaires indicates a lack of precision, especially when applied at the individual patient level.

Pyridostigmine in postpolio syndrome: no decline in fatigue and limited functional improvement

OBJECTIVES

To investigate the effect of pyridostigmine on fatigue, physical performance, and muscle function in subjects with postpoliomyelitis syndrome.

METHODS

67 subjects with increased fatigue and new weakness in one quadriceps muscle showing neuromuscular transmission defects, were included in a randomised, double blind, placebo controlled trial of 60 mg pyridostigmine four times a day for 14 weeks. Primary outcome was fatigue (on the "energy" category of the Nottingham health profile). Secondary outcomes included two minute walking distance and quadriceps strength and jitter. Motor unit size of the quadriceps was studied as a potential effect modifier. The primary data analysis compared the changes from baseline in the outcomes in the last week of treatment between groups.

RESULTS

31 subjects treated with pyridostigmine and 31 subjects treated with placebo completed the trial. No significant effect of pyridostigmine was found on fatigue. The walking distance improved more in the pyridostigmine group than in the placebo group (by 7.2 m (6.0%); p<0.01). Subgroup analysis showed that a significant improvement in walking performance was only found in subjects with normal sized motor units. Quadriceps strength improved more in the pyridostigmine group than in the placebo group (by 6.7 Nm (7.2%); p = 0.15). No effect of pyridostigmine was found on jitter.

CONCLUSIONS

Pyridostigmine in the prescribed dose did not reduce fatigue in subjects with postpoliomyelitis syndrome. However, it may have a limited beneficial effect on physical performance, especially in subjects with neuromuscular transmission defects in normal sized motor units.

Bromocriptine in the treatment of post-polio fatigue: a pilot study with implications for the pathophysiology of fatigue

Fatigue is the most commonly reported and most disabling of all post-polio sequelae (PPS). Bromocriptine mesylate (Parlodel) was employed in a placebo-controlled trial in five survivors of paralytic polio who continued to report moderate to severe daily fatigue after complying with the conservative treatments prescribed for PPS. Placebo was given for 4 wk followed by increasing doses of bromocriptine mesylate, administered at 12:00 pm for 28 days, which reached a total dose of 12.5 mg/day. Three subjects reported marked symptom improvement on bromocriptine but not on placebo. Their reported difficulty with attention, concentration, word finding, mind wandering, memory, thinking clearly, and fatigue on awakening was significantly negatively correlated with days on bromocriptine but not with days on placebo. Before the drug trial began, responders had clinically impaired performance on neuropsychologic tests of attention and information processing speed, more than twice as many hyperintensities on magnetic resonance imaging of the brain, abnormally low fasting adrenocorticotropic hormone levels, and nearly double the mean plasma prolactin level compared with nonresponders. The implications of these findings for the pathophysiology of fatigue are discussed. A double-blind, placebo-controlled, multicenter study will be needed to confirm bromocriptine's efficacy in treating attentionally and neurophysiologically impaired polio survivors whose severe and disabling fatigue does not respond to conservative therapies.