Treatment for periodic paralysis
Editorial Group: Cochrane Neuromuscular Group
Published Online: 23 JAN 2008
Assessed as up-to-date: 13 NOV 2007
Copyright © 2010 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
How to Cite
Sansone V, Meola G, Links T, Panzeri M, Rose MR. Treatment for periodic paralysis. Cochrane Database of Systematic Reviews 2008, Issue 1. Art. No.: CD005045. DOI: 10.1002/14651858.CD005045.pub2.
- Publication Status: Edited (no change to conclusions)
- Published Online: 23 JAN 2008
Primary periodic paralyses are rare inherited muscle diseases characterised by episodes of flaccid weakness affecting one or more limbs, lasting several hours to several days, caused by mutations in skeletal muscle channel genes.
The objective of this review was to systematically review treatment of periodic paralyses.
We searched the Cochrane Neuromuscular Disease Group Trials Register, MEDLINE (from January 1966 to July 2007), and EMBASE (from January 1980 to July 2007) and any other available international medical library sources from the University of Milan for randomised trials.
We included randomised (including cross-over studies) and quasi-randomised trials in participants with primary periodic paralyses, in which any form of treatment, including physical therapy and alternative therapies, was compared to placebo or another treatment.
Data collection and analysis
Our primary outcome measure was the change in attack severity or frequency by eight weeks from the start of treatment.
Our secondary outcome measures were: change in muscle strength and mass; change in Quality of Life, using Short Form 36 (SF36) or similar; preference of treatment strategy; adverse effects at eight weeks.
Three studies met our inclusion criteria. In one study dichlorphenamide (DCP) vs placebo was tested in two groups of participants: 42 with hypokalemic periodic paralysis (HypoPP) and 31 with hyperkalemic periodic paralysis (HyperPP), based on clinical criteria. Thirty-four of 42 participants with hypokalemic periodic paralysis completed both treatment phases. For the 34 participants having attack rate data for both treatment phases, the mean improvement in attack rate (P = 0.02) and severity-weighted attack rate (P = 0.01) on DCP relative to placebo were statistically significant. Fifteen preferred DCP, three placebo and six their baseline medication. Twenty-four of 31 participants with hyperkalemic periodic paralysis completed both treatment phases: for the 16 participants who had attack rate data for both treatment phases, the mean improvement in attack rate (P = 0.006) and in severity-weighted attack rate (P = 0.02) on DCP relative to placebo were significant. Fifteen preferred DCP, one placebo and five their baseline medication.
Acetazolamide proved to improve muscle strength in eight participants with HypoPP in one other study and pinacidil, a potassium channel opener, also improved muscle strength in 2/4 participants with HypoPP in a third study.
The largest included study that met our inclusion criteria suggested that DCP was effective in the prevention of episodic weakness in both hypokalemic and hyperkalemic periodic paralyses. The other two studies provide some evidence that either acetazolamide or pinacidil may improve muscle strength. However we still lack sufficient evidence to provide full guidelines for the treatment of people with periodic paralysis.
Plain language summary
Treatment for periodic paralysis
Muscle weakness and attacks of paralysis are two important features of periodic paralyses. Paralytic attacks occur in acute episodes and can be incapacitating. Attacks may last from several hours to several days according to the type of muscle channel involved. In some cases permanent muscle weakness can also occur. We are unsure whether such permanent muscle weakness is more likely to develop if the frequency of attacks is high and therefore might be less likely to occur if attacks are fully prevented by treatment. Although the treatment of choice in periodic paralysis is generally considered to be acetazolamide, there is no standardised treatment regimen and no consensus as to when to start treatment. We do not know if acetazolamide treatment prevents any permanent weakness that may occur.
We found two small studies demonstrating an improvement of muscle strength with pinacidil and acetazolamide. There was only one trial considering treatment of paralytic attacks, demonstrating a decrease in the severity and frequency of the attacks using diclorophenamide.
We did not find other randomised or quasi-randomised studies, but only case reports and anecdotal articles using other drugs to reduce paralyses attacks. Further research is needed to determine the best treatment for reducing the frequency and severity of attacks and to treat or prevent permanent muscle weakness.
搜尋的範圍包括:Cochrane Neuromuscular Disease Group Trials Register, MEDLINE (from January 1966 to July 2007), and EMBASE (from January 1980 to July 2007)。其他任何米蘭大學能取得的國際性醫學圖書管資源中的隨機試驗。
初級預後包含治療八週後陣發性麻痺發作的嚴重程度和頻率。二級預後包含肌力和肌肉質量的改變，生活品質的改變(使用Short Form 36;SF36或類似的評估方式)，病人喜愛的治療方式，使用八週後的副作用。
在我們設定的搜索條件下，總共找到三篇研究。其中一篇研究比較dichlorphenamide以及安慰劑:包含二組患者，一組是42位低血鉀周期性麻痺患者，一組是31位高血鉀周期性麻痺患者，進行dichlorphenamide和安慰劑二階段的治療。其中第一組的42位病患，有34位完成二階段的試驗並且在二個階段都有發作，其發作頻率還有發作的嚴重程度，在使用dichlorphenamide的那一組，和安慰劑相比都有臨床上有意義的改善。平均發作頻率的改善率P = 0.02，嚴重程度加權發作率P = 0.01。有15位病患較滿意dichlorphenamide的治療，有3位病患較滿意安慰劑的治療，有六位病患較滿意原本在使用的藥物。另外一組31位高血鉀陣發性麻痺的患者，有24人完成試驗，有16位病患在二個治療階段都有發作，得到的改善也是有統計上的意義，頻均發作頻率的改善率P = 0.006，嚴重程度加權發作率P = 0.02。這一組的滿意度調查，有15個人選擇dichlorphenamide，有一位選擇安慰劑，有五位選擇原本的治療方式。 第二個試驗中有八位低血鉀陣發性麻痺的病患使用乙?唑胺(Acetazolamide)能增加肌力。 第三個試驗中低血鉀陣發性麻痺的病患使用鉀離子通道作用劑pinacidil，有2/4的病患肌力改善。
此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。