Anticonvulsants for alcohol withdrawal

BACKGROUND

Alcohol withdrawal syndrome is a cluster of symptoms that occurs in alcohol-dependent people after cessation or reduction in alcohol use. This systematic review focuses on the evidence of anticonvulsants' use in the treatment of alcohol withdrawal symptoms.

OBJECTIVES

To evaluate the effectiveness and safety of anticonvulsants in the treatment of alcohol withdrawal.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2004); MEDLINE (1966 to October 2004); EMBASE (1988 to October 2004) and EU-PSI PSI-Tri database with no language and publication restrictions and references of articles.

SELECTION CRITERIA

All randomized controlled trials examining the effectiveness, safety and overall risk-benefit of an anticonvulsant in comparison with a placebo or other pharmacological treatment or another anticonvulsant were considered.

DATA COLLECTION AND ANALYSIS

The authors independently assessed trial quality extracted data.

MAIN RESULTS

Forty-eight studies, involving 3610 people were included. Despite the considerable number of randomized controlled trials, there was a variety of outcomes and of different rating scales that led to a limited quantitative synthesis of data. For the anticonvulsant versus placebo comparison, therapeutic success tended to be more common among the anticonvulsant-treated patients (relative risk (RR) 1.32; 95% confidence interval (CI) 0.92 to 1.91), and anticonvulsant tended to show a protective benefit against seizures (RR 0.57; 95% CI 0.27 to 1.19), but no effect reached formal statistical significance. For the anticonvulsant versus other drug comparison, CIWA-Ar score showed non-significant differences for the anticonvulsants compared to the other drugs at the end of treatment (weighted mean difference (WMD) -0.73; 95% CI -1.76 to 0.31). For the subgroup analysis of carbamazepine versus benzodiazepine, a statistically significant protective effect was found for the anticonvulsant (WMD -1.04; 95% CI -1.89 to -0.20), p = 0.02), but this was based on only 260 randomized participants. There was a non-significant decreased incidence of seizures (RR 0.50; 95% CI 0.18 to 1.34) favouring the patients that were treated with anticonvulsants than other drugs, and side-effects tended to be less common in the anticonvulsant-group (RR 0.56; 95% CI 0.31 to 1.02).

AUTHORS' CONCLUSIONS

It is not possible to draw definite conclusions about the effectiveness and safety of anticonvulsants in alcohol withdrawal, because of the heterogeneity of the trials both in interventions and the assessment of outcomes. The extremely small mortality rate in all these studies is reassuring, but data on other safety outcomes are sparse and fragmented.

Randomised trials comparing chemotherapy regimens for advanced non-small cell lung cancer: biases and evolution over time

We systematically evaluated the evidence from randomised trials comparing various chemotherapy regimens for advanced non-small cell lung cancer. Across 254 eligible trials (42661 patients), no regimens were compared in >6 studies. Twenty-six trials (10%) found statistically significant differences in survival between the compared arms. Only five reported the randomisation mode, and four reported adequate allocation concealment; nine performed unaccounted interim analyses. Statistical significance was more common in larger (P=0.003), more recent studies (P=0.031), and trials from countries with only one published eligible study (P=0.008). Increased reported median survival was independently associated with platinum and/or taxane and combination regimens, but also with the year of publication, smaller sample size, and larger representation of non-stage IV patients and patients with a better performance status. The proportion of enrolled patients with a performance status of 2 or worse decreased significantly over time (12.9% per decade, P<0.001). Randomised evidence in this field is fragmented and subject to considerable selection biases.