The impact of the February 2012 cold spell on health in Italy using surveillance data

PLoS One. 2013 Apr 18;8(4):e61720. doi: 10.1371/journal.pone.0061720. Print 2013.

Abstract

In February 2012 Italy was hit by an exceptional cold spell with extremely low temperatures and heavy snowfall. The aim of this work is to estimate the impact of the cold spell on health in the Italian cities using data from the rapid surveillance systems. In Italy, a national mortality surveillance system has been operational since 2004 in 34 cities for the rapid monitoring of daily mortality. Data from this system were used to evaluate the impact of the February 2012 cold spell on mortality shortly after the occurrence of the event. Furthermore, a cause-specific analysis was conducted in Roma using the Regional Mortality Registry and the emergency visits (ER) surveillance system. Cold spell episodes were defined as days when mean temperatures were below the 10(th) percentile of February distribution for more than three days. To estimate the impact of the cold spell, excess mortality was calculated as the difference between observed and daily expected values. An overall 1578 (+25%) excess deaths among the 75+ age group was recorded in the 14 cities that registered a cold spell in February 2012. A statistically significant excess in mortality was observed in several cities ranging from +22% in Bologna to +58% in Torino. Cause-specific analysis conducted in Roma showed a statistically significant excess in mortality among the 75+ age group for respiratory disease (+64%), COPD (+57%), cardiovascular disease +20% ischemic heart disease (14%) and other heart disease (+33%). Similar results were observed for ER visits. Surveillance systems need to become are a key component of prevention plans as they can help improve public health response and are a valid data source to rapidly quantify the impact on health. Cold-related mortality is still an important issue and should not be underestimated by public health Authorities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cardiovascular Diseases / mortality*
  • Cities
  • Cold Temperature*
  • Emergency Service, Hospital / statistics & numerical data
  • Epidemiological Monitoring*
  • Humans
  • Italy / epidemiology
  • Respiratory Tract Diseases / mortality*
  • Weather*

Grants and funding

This work was carried out within the National Program for the Prevention of Heat Health Effects funded by the Italian Ministry of Health and the EU project “Public Health Adaptation Strategies to Extreme weather events – PHASE” (contract number EAHC 20101103). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.