The occurrence of major cardiovascular events is not randomly distributed over time, but exhibits chronobiological patterns, i.e., circadian, weekly, or seasonal. No systematic studies on the temporal occurrence of Takotsubo cardiomyopathy (TTC) onset and the influence of the weather are known. The aim of this study was to evaluate the impact of the weather on the TTC onset.

Between 2015 and 2019, 70 patients hospitalized for TTC were retrospectively enrolled in this study. Thirty patients with consecutive acute myocardial infarction (AMI) were matched by age and sex and selected as group control patients, during the same length of time. We reported the season, the date and the time of the TTC. We collected weather data such as the temperature, the atmospheric pressure (in hPa), the duration of daily sunshine (number of hours per day) and the presence or absence of rain, cloud, fog, storm or snow 3 days before the TTC.

TTC and AMI occurred more often in winter (41.4% and 40% respectively). TTC happened more often during the week (77.1%) and during the daylight (8 a.m–8 p.m) (73%) in comparison with the AMI group (56.7% P=0.039 and 66.7% P=0.39 respectively). There were more TTC on Tuesday and Wednesday (18.6% and 17.1%) than AMI (0% and 0% P=0.011 and P=0.016 respectively). Furthermore, more AMI (66.7%) occurred mostly when the weather was foggy 3 days before than TTC (41.4% P=0.021). AMI (10%) was more present when it was snowing than TTC (1.4% P=0.045) (Fig. 1). The difference between the minimum and the maximum of the sunshine duration during the 3 days before was 6.3±3.4hours for the TTC group and 6.1±2.4hours for the AMI group (P=0.809).

A possible influence by meteorological trigger seems to exist on TTC onset and needs more investigations. There seems to be a crucial role of light by the circadian system.