Evaluation of a Patient-Specific Index as an outcome measure for physiotherapy in Parkinson's disease

AIM

The aim of this paper was to develop and evaluate a patient-specific index for physiotherapy in Parkinson's disease (PSI-PD).

METHODS

In the PSI-PD, patients 1) select problematic activities out of a predefined list, with one self-report item; 2) rank selected items in order of importance; and 3) rate severity for each ranked item. To examine test-retest reliability, a cohort of patients was asked to complete the PSI-PD twice. Afterwards, validity was evaluated using a telephone interview.

RESULTS

The PSI-PD was completed twice by 81 patients. Test-retest agreement for the selection of activity limitations was 73% to 94%. Items ranked by patients were categorized into domains, of which gait, transfers and dexterity were rated most frequently (41%-70%). Test-retest agreement for ranked domains ranged from 74% to 82%. Interviews confirmed that the PSI-PD reliably identified problem areas.

CONCLUSIONS

The PSI-PD is a relevant, reliable and valid instrument to identify limitations in everyday activities that are important for both PD patients and physiotherapists.

Anticonvulsant drugs for migraine prophylaxis

BACKGROUND

Anticonvulsant drugs seem to be useful in clinical practice for the prophylaxis of migraine. This might be explained by a variety of actions of these drugs in the central nervous system that are probably relevant to the pathophysiology of migraine.

OBJECTIVES

To describe and assess the evidence from controlled trials on the efficacy and tolerability of anticonvulsants for preventing migraine attacks in adult patients with migraine.

SEARCH STRATEGY

We searched MEDLINE (from 1966 on) and the Cochrane Central Register of Controlled Trials (CENTRAL). Date of most recent search: April 2003. Additional information was gained from hand-searching specialist headache journals; correspondence with pharmaceutical companies, authors of reports, and experts in the field; and a wide variety of review articles and book chapters.

SELECTION CRITERIA

Studies were required to be prospective, controlled trials of self-administered drug treatments taken regularly to prevent the occurrence of migraine attacks and/or to reduce the intensity of those attacks.

DATA COLLECTION AND ANALYSIS

Studies were selected and data extracted by two independent reviewers. For migraine frequency data, standardized mean differences (SMDs) were calculated for individual studies and pooled across studies. For dichotomous data on significant reduction in migraine frequency, odds ratios (ORs) and numbers-needed-to-treat (NNTs) were similarly calculated. Adverse events were analyzed by calculating numbers-needed-to-harm (NNHs) for studies using similar agents.

MAIN RESULTS

Fifteen papers were included in the review. Of these, 14 reported trials comparing anticonvulsants with placebo, as follows: four trials of divalproex sodium, three trials of topiramate, two trials of sodium valproate, two trials of gabapentin, and one trial each of carbamazepine, clonazepam, and lamotrigine. One paper reported a trial of sodium valproate versus an active comparator, flunarizine, and one trial of divalproex sodium versus placebo included a comparison against propranolol, also an active comparator. Data from 2024 patients were considered. Analysis of data from eight trials (n = 841) demonstrates that anticonvulsants, considered as a class, reduce migraine frequency by about 1.4 attacks per 28 days as compared to placebo (SMD -0.60; 95% confidence interval [CI] -0.93 to -0.26). Data from 10 trials (n = 1341) show that anticonvulsants, considered as a class, also more than double the number of patients for whom migraine frequency is reduced by 50% or more, relative to placebo (OR 3.90; 95% CI 2.61 to 5.82; NNT 3.8; 95% CI 3.2 to 4.6). For seven trials of sodium valproate and divalproex sodium, NNHs for five clinically important adverse events ranged from 6.6 to 16.3. For the three trials of topiramate, NNHs for eight adverse events (100-mg dose) ranged from 2.4 to 32.9.

REVIEWERS' CONCLUSIONS

Anticonvulsants appear to be both effective in reducing migraine frequency and reasonably well tolerated. There is noticeable variation among individual agents, but there are insufficient data to know whether this is due to chance or variation in true efficacy. Neither clonazepam nor lamotrigine was superior to placebo (one trial each). Relatively few robust trials are available for agents other than sodium valproate/divalproex sodium. Two recently published and large trials of topiramate demonstrated reasonable efficacy, and one further trial of this agent is anticipated in the near future.

Might migraine damage the brain?

Recent debate concerning the interpretation of studies of regional cerebral blood flow in migraine has re-emphasized that cerebral ischaemia may occur during attacks of migraine with aura. In this article we suggest that the presence of ischaemia during attacks makes it possible that migraine with aura causes neuronal damage in the long term. We argue that damage is likely to occur in the primary visual cortex, given that a recent high-resolution rCBF study has found flow reductions confined to this area. Furthermore, we hypothesize that the extent to which rCBF is reduced in migraine with aura is sufficient to cause damage only to GABA-ergic inhibitory interneurons in layer IV of this cortex. In animal models, similar cells are known to be selectively vulnerable to damage as a result of hypoxic conditions. Evidence consistent with our hypothesis is provided by recent studies of visual function in migraine. Some clinical and pathophysiological implications of this hypothesis are discussed.