Seasonality in Causes of Death in Italian Regions: A Statistical Exploration Using Circular Data Analysis

Isabella Marinetti, Max Planck Institute for Demographic Research (MPIDR)
Francesco Lagona, Department of Political Sciences, Roma Tre University, Rome, Italy
Dmitri A. Jdanov, Max Planck Institute for Demographic Research / National Research University Higher School of Economics

Seasonal variations play a significant role in mortality patterns, with deaths often peaking during winter due to respiratory and cardiovascular diseases. Understanding these seasonal trends is critical for assessing their impact on mortality and life expectancy. While most studies focus on annual data, our research aims to uncover cause-specific seasonal mortality trends within Italy’s subnational territories from 2004 to 2019. We used daily death counts by cause of death (ICD-10) from the Italian National Statistical Office (ISTAT) database, categorised into seven major cause groups. A circular data analysis method was applied to model daily mortality trends, accounting for the cyclical nature of seasons and identifying seasonal mortality patterns across Italian groups of regions (NUTS 1 level). Our analysis revealed distinct seasonal peaks in mortality due to respiratory infections and cardiovascular diseases, especially during winter months, with mortality rates increasing by about 20% compared to other seasons. The South and Insular regions showed larger fluctuations in cardiovascular deaths, although with generally lower mortality rates than northern regions. Using circular data methods will further enhance understanding of these trends, which are critical for targeted public health interventions.

Keywords: Mortality and Longevity, Health and Morbidity, Spatial Demography, Data and Methods

See extended abstract.