Nationwide Analysis of the Relationship Between Low Ambient Temperature and Acute Aortic Dissection-related Hospitalizations.

Aims: Acute aortic dissection (AAD) is a life-threatening cardiovascular emergency. Therefore, identifying modifiable risk factors for AAD is of great public health significance. An association between ambient temperature (AT) and AAD has been reported; however, not all findings have been elucidated. This study examined the association between AAD-related hospitalization and AT using data from the Japanese Registry of All Cardiac and Vascular Diseases Diagnostic Procedure Combination (JROAD-DPC), which is a nationwide claims-based database.

Methods: This nationwide time-stratified case-crossover study evaluated data of hospitalized patients with AAD from 1,119 certified hospitals between 2012 and 2020 using the JROAD-DPC database. Conditional logistic regression and distributed lag non-linear models were used to investigate the association between average daily temperature and AAD-related hospitalization.

Results: Among the 96,812 cases analyzed. The exposure-response curve between AT and AAD-related hospitalization showed an increase in the odds ratio for lower temperatures, with a peak at timed -10°C (odds ratio: 2.28, 95% confidence interval: 1.92-2.71, compared with that at 20°C). The effects of temperature on lag days 0 and 1 were also significant.Stratified analyses showed a greater association between AT and AAD-related hospitalization for the following variables: older age (≥75 years), female sex (44.4%, the mean age ± SD was 76 ± 12 years), low body mass index (<22), winter season, and warmer regions.

Conclusions: Low AT is associated with an increased risk of AAD-related hospitalization. Several susceptible groups are affected by cold temperatures and have a higher risk of hospitalization.