Weekend effect and short-term mortality in patients with acute pulmonary embolism: systematic review and meta-analysis

We systematically reviewed the available literature and performed a meta-analysis of data from cohort studies to estimate the association between weekend admission and early mortality in patients diagnosed with acute pulmonary embolism (PE). Statistical heterogeneity between groups was measured using the Higgins I2 statistic. Data were pooled using a random-effects models with odds ratio (OR) and related 95% CI. Publication bias was evaluated both by the Egger's test and by visual examination of the corresponding funnel plot. Among the 12 studies reviewed, based on 1.782.385 patients with PE, the pooled analysis showed that patients admitted during the weekend had a higher risk of 30-day or in-hospital death than those admitted during weekdays (unadjusted OR: 1.17; 95% CI 1.13-1.20, P < 0.0001, I2 = 36.6%). A sub-analysis based on the adjusted OR derived from those studies performing a multivariate regression analysis confirmed yielded results (adjusted OR: 1.15, 95% CI 1.07-1.75, P < 0.0001, I2 = 0%). In conclusion, patients admitted during weekend for acute pulmonary embolism are characterized by an approximately 15% excess in the risk of early death, defined as either 30-day or in-hospital death.