Impact of emerging virus pandemics on cause-specific maternal mortality time series: a population-based natural experiment using national vital statistics, Argentina 1980-2017

María Elena Critto; Yordanis Enriquez; Miguel Bravo; Lenin de Janon Quevedo; Ruth Weinberg; Adolfo Etchegaray; Elard S Koch

doi:10.1016/j.lana.2021.100116

Impact of emerging virus pandemics on cause-specific maternal mortality time series: a population-based natural experiment using national vital statistics, Argentina 1980-2017

Lancet Reg Health Am. 2021 Nov 19:6:100116. doi: 10.1016/j.lana.2021.100116. eCollection 2022 Feb.

Authors

María Elena Critto^{1

2}, Yordanis Enriquez³, Miguel Bravo^{1

4}, Lenin de Janon Quevedo⁵, Ruth Weinberg⁶, Adolfo Etchegaray⁷, Elard S Koch¹

Affiliations

¹ Division of Epidemiology, MELISA Institute, Concepción, Chile.
² Programa de Doctorado en Sociología, Facultad de Ciencias Sociales, Pontificia Universidad Católica de Argentina, Ciudad de Buenos Aires, Argentina.
³ Facultad de Ciencias de la Salud, Universidad Católica Sedes Sapientiae, Lima, Perú.
⁴ School of Public Health, Faculty of Medicine, University of Chile, Santiago, Chile.
⁵ Facultad de Ciencias Médicas, Pontificia Universidad Católica de Argentina, Ciudad de Buenos Aires, Argentina.
⁶ Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
⁷ Hospital Universitario Austral, Facultad de Medicina, Universidad Austral, Buenos Aires, Argentina.

Abstract

Background: Emerging pandemic viruses may have multiple deleterious effects on maternal health. This study examines the effects of a pandemic influenza virus on cause-specific maternal mortality time series, using Argentinian vital statistics.

Methods: We conducted a population-based natural experiment from national vital records of maternal deaths between 1980 and 2017. Joinpoint regression models were used to model time series of the maternal mortality ratio (MMR). The sensitivity of the registry to detect the effects of the pandemic H1N1 2009 influenza virus on cause-specific MMR was analysed using a panel of parallel interrupted time series (ITS).

Findings: Over this 38-year study, the MMR decreased by 58·6% (69·5 to 28·8 deaths/100,000 live births), transitioning from direct obstetric causes (67·0 to 21·1/100,000 live births; 68·4% decrease) to indirect causes (2·6 to 7·7/100,000 live births; 196·2% increase). The regression analysis showed an average reduction of -2·2%/year (95% CI: -2·9 to -1·4) with 2 join points in the total trend (1998 and 2009). Parallel ITS analyses revealed the pandemic H1N1 virus had an increasing effect on mortality from the respiratory system- and sepsis-related complications (level change 4·7 and 1·6/100,000 live births respectively), reversing after the outbreak. No effect was found on MMR from hypertensive disorders, haemorrhage, abortive outcomes, other direct obstetric causes, and indirect non-respiratory comorbidities.

Interpretation: The Argentinian maternal death registry appears sensitive to detect different effects of emerging infectious epidemics on maternal health. In a population-based natural experiment, pandemic H1N1 virus impacted maternal mortality almost exclusively from the respiratory system- and sepsis-related complications.

Funding: Supported by FISAR www.fisarchile.org.

Keywords: AAPC, average annual percentage change; APC, annual percentage change; A[H1N1]pmd09, H1N1 pandemic A influenza virus 2009; Argentina; H1N1 Virus; ICD, International Classification of Diseases; ITS, Interrupted Time Series; Interrupted Time Series Analysis; MMR, maternal mortality ratio; Maternal Mortality; Pandemics; Public Health Surveillance; WHO, World Health Organization.