Subgroup Analysis in Meta-Analysis: a comparison of different methods

Two-dimensional echocardiography using second harmonic imaging for the diagnosis of intracardiac right-to-left shunt: a meta-analysis of prospective studies

Right-to-left shunting (RLS), usually through a patent foramen ovale (PFO), has been associated with migraine, cryptogenic stroke and hypoxemia. With emerging observational studies and clinical trials on the subject of PFO, there is a need for accurate diagnosis of PFO in patients being considered for transcatheter closure. While transesophageal echo (TEE) bubble study is the current standard reference for diagnosing PFO, transthoracic echo with second harmonic imaging (TTE-HI) may be a preferable screening test for RLS due to its high accuracy and non-invasiveness. The aim of this meta-analysis was to determine the accuracy of TTE-HI compared to TEE as the reference. A systematic review of Medline, Cochrane and Embase was done for all the prospective studies assessing for intracardiac RLS using TTE-HI compared to TEE as the reference; both TTE-HI and TEE were performed with a contrast agent and a maneuver to provoke RLS in all studies. A total of 15 studies with 1995 patients fulfilled the inclusion criteria. The weighted mean sensitivity and specificity for TTE-HI were 91 and 93 % respectively. Likewise, the positive and negative likelihood ratios were 13.52 and 0.13 respectively. TTE-HI is a reliable, non-invasive test with proficient diagnostic accuracies. The high sensitivity and specificity of TTE-HI make it a useful initial screening test for RLS. If the precise anatomy is required, then TEE can be obtained before scheduling a patient for transcatheter PFO closure.

Interventions for reducing benzodiazepine use in older people: meta-analysis of randomised controlled trials

BACKGROUND

The use of benzodiazepines has been advised against in older people, but prevalence rates remain high.

AIMS

To review the evidence for interventions aimed at reducing benzodiazepine use in older people.

METHOD

We conducted a systematic review, assessment of risk of bias and meta-analyses of randomised controlled trials of benzodiazepine withdrawal and prescribing interventions.

RESULTS

Ten withdrawal and eight prescribing studies met the inclusion criteria. At post-intervention, significantly higher odds of not using benzodiazepines were found with supervised withdrawal with psychotherapy (odds ratio (OR) = 5.06, 95% CI 2.68-9.57, P<0.00001) and withdrawal with prescribing interventions (OR = 1.43, 95% CI 1.02-2.02, P = 0.04) in comparison with the control interventions treatment as usual (TAU), education placebo, withdrawal with or without drug placebo, or psychotherapy alone. Significantly higher odds of not using benzodiazepines were also found for multifaceted prescribing interventions (OR = 1.37, 95% CI 1.10-1.72, P = 0.006) in comparison with control interventions (TAU and prescribing placebo).

CONCLUSIONS

Supervised benzodiazepine withdrawal augmented with psychotherapy should be considered in older people, although pragmatic reasons may necessitate consideration of other strategies such as medication review.

Diagnostic value of circulating tumor cell detection in bladder and urothelial cancer: systematic review and meta-analysis

Background

The diagnostic value and prognostic significance of circulating tumor cell (CTC) detection in patients with bladder cancer is controversial. We performed a meta-analysis to consolidate current evidence regarding the use of CTC detection assays to diagnose bladder and other urothelial cancers and the association of CTC positivity with advanced, remote disease.

Methods

Studies that investigated the presence of CTCs in the peripheral blood of patients with bladder cancer and/or urothelial cancer were identified and reviewed. Sensitivities, specificities, and positive (LR+) and negative likelihood ratios (LR-) of CTC detection in individual studies were calculated and meta-analyzed by random effects model. Overall odds ratio of CTC positivity in patients with advanced disease versus those with organ-confined cancer was also calculated.

Results

Overall sensitivity of CTC detection assays was 35.1% (95%CI, 32.4-38%); specificity, LR+, and LR- was 89.4% (95%CI, 87.2-91.3%), 3.77 (95%CI, 1.95-7.30) and 0.72 (95%CI, 0.64-0.81). CTC-positive patients were significantly more likely to have advanced (stage III-IV) disease compared with CTC-negative patients (OR, 5.05; 95%CI, 2.49-10.26).

Conclusions

CTC evaluation can confirm tumor diagnosis and identify patients with advanced bladder cancer. However, due to the low overall sensitivity, CTC detection assays should not be used as initial screening tests.