The rise and fall of excess winter mortality over a century in a high-income country: New Zealand from 1876 to 2020

Abstract Excess winter mortality (EWM) has been used as a measure of how well populations and policy moderate the health effects of cold weather. We aimed to investigate long-term changes in Aotearoa New Zealand (NZ) EWM, and potential drivers of change, and test for structural breaks in trends. We calculated NZ EWM indices from 1876 (4,698 deaths) to 2020 (33,310 deaths), total and by age-group and sex, comparing deaths June to September (the coldest months) to deaths February to May and October to January. The mean age and sex-standardised EWM Index (EWMI) for the full study period, excluding 1918, was 1.22. However, mean EWMI increased from 1.20 for 1886 to 1917, to 1.34 for the 1920s, then reduced over time to 1.14 in the 2010s, with excess winter deaths averaging 4.5% of annual deaths (1,450 deaths per year) in the 2010s, compared to 7.9% in the 1920s. Children under 5 years transitioned from a summer to winter excess between 1886 and 1911. Otherwise, the EWMI age-distribution was J-shaped in all time periods. Structural break testing showed the 1918 influenza strain had a significant impact on trends in winter and non-winter mortality and winter excess for subsequent decades. It was not possible to attribute the post-1918 reduction in EWM to any single factor among improved living standards, reduced severe respiratory infections, or climate change..

Medienart:

Preprint

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

ResearchSquare.com - (2023) vom: 04. Dez. Zur Gesamtaufnahme - year:2023

Sprache:

Englisch

Beteiligte Personen:

Telfar-Barnard, Lucy [VerfasserIn]
Baker, Michael G [VerfasserIn]
Wilson, Nick [VerfasserIn]
Howden-Chapman, Philippa [VerfasserIn]

Links:

Volltext [lizenzpflichtig]
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Themen:

570
Biology

doi:

10.21203/rs.3.rs-3204677/v1

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

XRA040552993