Shah KB, Saado J, Kerwin M, et al. - In the setting of noncardiac critical illness, elevated in-hospital mortality was observed in relation to new-onset secondary atrial fibrillation (NOSAF) vs no history of atrial fibrillation (AF) and previous AF. Increased long-term mortality was also evident in relation to NOSAF (vs no history of AF).

• Among noncardiac critically ill patients, the effect of NOSAF vs history of prior AF and no history of AF was evaluated via a systematic review and meta-analysis of 19 eligible studies with 306,805 patients.

• Elevated in-hospital mortality (risk ratio [RR] 2.06), longer ICU length of stay (LOS) (standardized difference in means [SMD] 0.66), longer hospital LOS (SMD 0.31) and increased risk of long-term (>1 year) mortality (RR 1.76) all were observed in relation to NOSAF vs no history of AF.

• NOSAF vs previous AF was also related to higher in-hospital death (RR 1.29), longer ICU LOS (SMD 0.37) but no difference in-hospital LOS (SMD −0.18).