A focus on three hot topics: atrial fibrillation, obesity, and climate change.

This article focuses on three topics: atrial fibrillation, obesity, and climate change. The first study examines the risks of cardiovascular diseases and mortality among patients with atrial fibrillation (AF) based on age at diagnosis. The findings show that earlier diagnosis of AF is associated with a higher risk of subsequent cardiovascular disease and shorter life expectancy. The second study explores the long-term outcomes and mortality rates for patients hospitalized with AF or flutter. The results indicate high death rates and re-hospitalizations for AF or flutter, highlighting the need for further actions and treatment strategies. The third study investigates the causal associations of body mass index (BMI) and waist circumference (WC) with mortality in the oldest-old population. The findings reveal opposite associations, with higher BMI and lower WC linked to decreased mortality risk. The article also includes a study on the association between nocturnal heat exposure and stroke risk, as well as commentary and responses on the obesity paradox. [Extracted from the article]