Prognostic factors for mortality in neonatal tetanus: a systematic review and meta-analysis.

OBJECTIVES To determine prognostic factors for mortality in neonates with tetanus and to assess the associations between prognostic factors and neonatal tetanus (NT) mortality. METHODS Five databases were searched for studies on prognostic factors and NT mortality published up to April 2013 to identify studies relevant to this review. Prognostic factors of interest were birth weight, age at onset of symptoms, age at presentation, delay in presentation, and duration of hospitalization. Odds ratios (ORs) for prognostic factors and mortality were estimated by random effects models and stratified analyses for all studies. RESULTS Sixteen studies including a total of 4535 neonates were included in the analysis: nine from Africa, five from Asia, and two from Europe. The prognostic factors identified consistently in the studies were birth weight, age at onset of symptoms, and age at presentation. Of the 16 studies, only one assessed all three prognostic factors, five studies assessed two prognostic factors, and 10 studies assessed one prognostic factor. Neonates with a low birth weight were more likely to have an increased odds of NT death (OR 2.09, 95% confidence interval (CI) 1.29-3.37) than normal weight neonates. This mortality risk was exacerbated for low birth weight neonates with age at onset≤6 days (OR 6.80, 95% CI 2.42-19.11). Age at onset≤5-7 days was associated with an increased odds of NT death. CONCLUSIONS Low birth weight predicted an increased odds of death by NT. Age at onset≤5-7 days to diagnosis is crucial in determining survival among neonates with tetanus.