Temperature-mortality associations by age and cause: a multi-country multi-city study.

Background: Heterogeneity in temperature-mortality relationships across locations may partly result from differences in the demographic structure of populations and their cause-specific vulnerabilities. Here we conduct the largest epidemiological study to date on the association between ambient temperature and mortality by age and cause using data from 532 cities in 33 countries.

Methods: We collected daily temperature and mortality data from each country.

Maternal ozone exposure lowers infant's birthweight: A nationwide cohort of over 4 million livebirths in Iran.

Background: Nationwide evidence linking maternal ozone exposure with fetal growth restriction (FGR) was extensively scarce, especially in the Middle East with dry climate and distinct religious culture.

Methods: We carried out a national retrospective birth cohort study using registry-based records from 749 hospitals across 31 provinces in Iran from 2013 to 2018. Monthly concentrations of maximum daily average 8-hour (MDA8) ozone at 0.

Surrounding greenness is associated with lower risk and burden of low birth weight in Iran.

The nexus between prenatal greenspace exposure and low birth weight (LBW) remains largely unstudied in low- and middle-income countries (LMICs). We investigated a nationwide retrospective cohort of 4,021,741 live births (263,728 LBW births) across 31 provinces in Iran during 2013-2018. Greenness exposure during pregnancy was assessed using satellite-based normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI).

Interactive effects of ambient fine particulate matter and ozone on daily mortality in 372 cities: two stage time series analysis.

Objective: To investigate potential interactive effects of fine particulate matter (PM) and ozone (O) on daily mortality at global level.

Design: Two stage time series analysis.

Setting: 372 cities across 19 countries and regions.

Associations Between Extreme Temperatures and Cardiovascular Cause-Specific Mortality: Results From 27 Countries.

Background: Cardiovascular disease is the leading cause of death worldwide. Existing studies on the association between temperatures and cardiovascular deaths have been limited in geographic zones and have generally considered associations with total cardiovascular deaths rather than cause-specific cardiovascular deaths.

Methods: We used unified data collection protocols within the Multi-Country Multi-City Collaborative Network to assemble a database of daily counts of specific cardiovascular causes of death from 567 cities in 27 countries across 5 continents in overlapping periods ranging from 1979 to 2019.

Effect modification of greenness on the association between heat and mortality: A multi-city multi-country study.

Background: Identifying how greenspace impacts the temperature-mortality relationship in urban environments is crucial, especially given climate change and rapid urbanization. However, the effect modification of greenspace on heat-related mortality has been typically focused on a localized area or single country. This study examined the heat-mortality relationship among different greenspace levels in a global setting.

Global, regional, and national burden of mortality associated with short-term temperature variability from 2000-19: a three-stage modelling study.

Background: Increased mortality risk is associated with short-term temperature variability. However, to our knowledge, there has been no comprehensive assessment of the temperature variability-related mortality burden worldwide. In this study, using data from the MCC Collaborative Research Network, we first explored the association between temperature variability and mortality across 43 countries or regions.

Fluctuating temperature modifies heat-mortality association around the globe.

Studies have investigated the effects of heat and temperature variability (TV) on mortality. However, few assessed whether TV modifies the heat-mortality association. Data on daily temperature and mortality in the warm season were collected from 717 locations across 36 countries.

Reduction in daily ambient PM pollution and potential life gain by attaining WHO air quality guidelines in Tehran.

Background: Fine particulate matter pollution (PM) is widely considered to be a top-ranked risk factor for premature mortality and years of life lost (YLL). However, evidence regarding the effect of daily air quality improvement on life expectancy is scarce, especially in the Middle East such as Iran. This study aimed to investigate the potential benefits in life expectancy at concentrations meeting the daily PM standards during 2012-2016 in Tehran, Iran.

Geographical Variations of the Minimum Mortality Temperature at a Global Scale: A Multicountry Study.

Background: Minimum mortality temperature (MMT) is an important indicator to assess the temperature-mortality association, indicating long-term adaptation to local climate. Limited evidence about the geographical variability of the MMT is available at a global scale.

Methods: We collected data from 658 communities in 43 countries under different climates.

Mortality risk attributable to wildfire-related PM pollution: a global time series study in 749 locations.

Background: Many regions of the world are now facing more frequent and unprecedentedly large wildfires. However, the association between wildfire-related PM and mortality has not been well characterised. We aimed to comprehensively assess the association between short-term exposure to wildfire-related PM and mortality across various regions of the world.

Global, regional, and national burden of mortality associated with non-optimal ambient temperatures from 2000 to 2019: a three-stage modelling study.

Background: Exposure to cold or hot temperatures is associated with premature deaths. We aimed to evaluate the global, regional, and national mortality burden associated with non-optimal ambient temperatures.

Methods: In this modelling study, we collected time-series data on mortality and ambient temperatures from 750 locations in 43 countries and five meta-predictors at a grid size of 0·5° × 0·5° across the globe.

Exposure to suboptimal ambient temperature during specific gestational periods and adverse outcomes in mice.

Exposure to suboptimal ambient temperature during pregnancy has been reported as a potential teratogen of fetal development. However, limited animal evidence is available regarding the impact of extreme temperatures on maternal pregnancy and the subsequent adverse pregnancy outcomes. Our objective in this study is to investigate the relationship between temperature and maternal stress during pregnancy in mice.

Utilizing daily excessive concentration hours to estimate cardiovascular mortality and years of life lost attributable to fine particulate matter in Tehran, Iran.

Background: Evidence for associations between fine particulate matter (PM) and cardiovascular diseases (CVDs) in Iran is scarce. Given large within-day variations of PM concentration, using the daily mean of PM (PMmean) as exposure metric might bias the health-related assessment. This study applied a novel indicator, daily excessive concentration hours (DECH), to evaluate the effect of ambient PM on CVD mortality and years of life lost (YLL) in Tehran, the capital city of Iran.

Short-term effects of particulate matter during desert and non-desert dust days on mortality in Iran.

Background: Increased atmospheric particulate matter (PM) concentrations are commonly observed during desert dust days in Iran, but there is still no evidence of their effects on human health. We aimed to evaluate the association between daily mortality and exposure to PM and PM during dust and non-dust days in Tehran and Ahvaz, two major Middle Eastern cities with different sources, intensity, and frequency of desert dust days.

Methods: We identified desert dust days based on exceeding a daily PM concentration threshold of 150 µg/m between 2014 and 2017, checking for low PM/PM ratio typical of dust days.

Heat Wave and Mortality: A Multicountry, Multicommunity Study.

Background: Few studies have examined variation in the associations between heat waves and mortality in an international context.

Objectives: We aimed to systematically examine the impacts of heat waves on mortality with lag effects internationally.

Methods: We collected daily data of temperature and mortality from 400 communities in 18 countries/regions and defined 12 types of heat waves by combining community-specific daily mean temperature ≥90th, 92.

Climate Change and Simulation of Cardiovascular Disease Mortality: A Case Study of Mashhad, Iran.

Background: Weather and climate play a significant role in human health. We are accustomed to affects the weather conditions. By increasing or decreasing the environment temperature or change of seasons, some diseases become prevalent or remove.

Effect of Air Temperature and Universal Thermal Climate Index on Respiratory Diseases Mortality in Mashhad, Iran.

Objective: Climatic factors with desired and sometimes undesired effects lead to changes in the human body, such as hypothermia, influenza, heart disease, stroke, asthma, etc. The present study investigates the role of temperature in respiratory mortality in Mashhad, Iran.

Materials And Methods: Among the respiratory mortality data, daily temperature, wind speed and relative humidity from 2004 to 2013 were used.