Effects of Air Temperature on Climate-Sensitive Mortality and Morbidity Outcomes in the Elderly; a Systematic Review and Meta-analysis of Epidemiological Evidence

Using GAM and DLNM to assess the impact of outdoor air quality on respiratory diseases in Nakhon Ratchasima municipality, Thailand

Long-term effects of outdoor air pollution on mortality and morbidity–prediction using nonlinear autoregressive and artificial neural networks models

Introduction: Ambient air pollution is a major contributor to respiratory morbidity and mortality globally, with disproportionate impacts in low- and middle-income countries. The Delhi–National Capital Region (NCR) experiences persistently high levels of air pollution, yet region-specific quantitative syntheses of respiratory health impacts remain limited. This study aimed to systematically review and meta-analyse epidemiological evidence on the association between ambient air pollution and respiratory outcomes in Delhi–NCR from 2010 to 2025. Methods: A systematic review and meta-analysis were conducted in accordance with PRISMA 2020 guidelines. PubMed/MEDLINE, Scopus, Web of Science, Embase, and additional sources were searched for eligible studies examining associations between ambient air pollutants (PM₂.₅, PM₁₀, NO₂, SO₂, O₃, CO) and respiratory morbidity or mortality in Delhi–NCR. Time-series, case-crossover, cohort, and observational studies reporting quantitative effect estimates were included. Random-effects meta-analyses were performed to derive pooled relative risks per 10 µg/m³ increase in pollutant concentration. Risk of bias was assessed using adapted ROBINS-E and Newcastle–Ottawa tools. Results: Ten studies met inclusion criteria for qualitative synthesis, and seven were included in meta-analysis. Short-term increases in PM₂.₅ were associated with higher respiratory emergency visits (RR 1.038; 95% CI: 1.021–1.056) and respiratory mortality (RR 1.019; 95% CI: 1.006–1.033). PM₁₀ exposure was linked to increased respiratory admissions (RR 1.026; 95% CI: 1.012–1.041), while NO₂ showed a strong association with acute respiratory visits (RR 1.041; 95% CI: 1.018–1.064). Heterogeneity ranged from low to moderate. Conclusion: Ambient air pollution is consistently associated with increased respiratory morbidity and mortality in Delhi–NCR. These findings underscore the urgent need for strengthened air quality interventions and targeted public health strategies in highly polluted urban settings.

Introduction: Ambient air pollution is a major contributor to respiratory morbidity and mortality globally, with disproportionate impacts in low- and middle-income countries. The Delhi–National Capital Region (NCR) experiences persistently high levels of air pollution, yet region-specific quantitative syntheses of respiratory health impacts remain limited. This study aimed to systematically review and meta-analyse epidemiological evidence on the association between ambient air pollution and respiratory outcomes in Delhi–NCR from 2010 to 2025. Methods: A systematic review and meta-analysis were conducted in accordance with PRISMA 2020 guidelines. PubMed/MEDLINE, Scopus, Web of Science, Embase, and additional sources were searched for eligible studies examining associations between ambient air pollutants (PM₂.₅, PM₁₀, NO₂, SO₂, O₃, CO) and respiratory morbidity or mortality in Delhi–NCR. Time-series, case-crossover, cohort, and observational studies reporting quantitative effect estimates were included. Random-effects meta-analyses were performed to derive pooled relative risks per 10 µg/m³ increase in pollutant concentration. Risk of bias was assessed using adapted ROBINS-E and Newcastle–Ottawa tools. Results: Ten studies met inclusion criteria for qualitative synthesis, and seven were included in meta-analysis. Short-term increases in PM₂.₅ were associated with higher respiratory emergency visits (RR 1.038; 95% CI: 1.021–1.056) and respiratory mortality (RR 1.019; 95% CI: 1.006–1.033). PM₁₀ exposure was linked to increased respiratory admissions (RR 1.026; 95% CI: 1.012–1.041), while NO₂ showed a strong association with acute respiratory visits (RR 1.041; 95% CI: 1.018–1.064). Heterogeneity ranged from low to moderate. Conclusion: Ambient air pollution is consistently associated with increased respiratory morbidity and mortality in Delhi–NCR. These findings underscore the urgent need for strengthened air quality interventions and targeted public health strategies in highly polluted urban settings.

Maternal smoking is associated with infant respiratory infections and with increased risk of low birth weight infants and preterm birth. This study assesses the association of maternal smoking during pregnancy with both respiratory and nonrespiratory infectious disease (ID) morbidity and mortality in infants. We conducted 2 retrospective case-control analyses of infants born in Washington State from 1987 to 2004 using linked birth certificate, death certificate and hospital discharge records. One assessed morbidity--infants hospitalized due to IDs within 1 year of birth (47,404 cases/48,233 controls). The second assessed mortality--infants who died within 1 year due to IDs (627 cases/2730 controls). Maternal smoking was associated with both hospitalization (adjusted odds ratio [AOR] = 1.52; 95% confidence interval [CI]: 1.46, 1.58) and mortality (AOR = 1.51; 95% CI: 1.17, 1.96) due to any ID. In subgroup analyses, maternal smoking was associated with hospitalization due to a broad range of IDs including both respiratory (AOR = 1.69; 95% CI: 1.63, 1.76) and nonrespiratory IDs (AOR = 1.27; 95% CI: 1.20, 1.34). Further stratification by birth weight and gestational age did not appreciably change these estimates. In contrast, there was no association of maternal smoking with ID infant mortality when only low birth weight infants were considered. Maternal smoking was associated with a broad range of both respiratory and nonrespiratory ID outcomes. Despite attenuation of the mortality association among low birth weight infants, ID hospitalization was found to be independent of both birth weight and gestational age. These findings suggest that full-term infants of normal weight whose mothers smoked may suffer an increased risk of serious ID morbidity and mortality.

Particulate matter (PM) exposure is a leading risk factor for cardiovascular and respiratory morbidity and mortality across the world. While arid and semi‐arid regions account for more than 40% of terrestrial land, there is a paucity of research investigating the relationship between PM exposure and health outcomes or how risk varies across different populations specific to these climate regions. To address this, we performed a scoping review to assess the extent of literature in arid and semi‐arid regions that consider such morbidity and mortality risks from short‐term PM exposure. Our review identified 102 studies published after 2012 located within four arid climate classifications: hot arid, cold arid, semi‐arid hot, and semi‐arid cold. The meta‐analysis found a pooled overall increased relative risk (RR) of both cardiovascular and respiratory mortality and morbidity, with an 8% higher risk of morbidity in hot arid regions (1.11, 95% confidence interval (CI): 1.05, 1.17) compared to cold semi‐arid regions (1.02, 95% CI: 1.00, 1.03) for adults (18–64). Further, we assessed effect modification (age, sex, population density and season) and found weak evidence of increased risk for both males and adults. The studies included in this review highlighted compounding risks, such as dust storms, wildfire, and extreme temperature, however there was a significant lack of studies situated in highly populated arid regions, with none identified in Africa. Given the public health burden from PM exposure and the impact of climate change and anthropogenic activities which destabilize land‐surfaces and increase dust emissions, additional focus is owed to demographic effect modifiers and the role of climate specific risks.

Cardiorespiratory effects of heatwaves: A systematic review and meta-analysis of global epidemiological evidence

Long-term respiratory outcomes in early-term born offspring: a systematic review and meta-analysis

Extreme weather events in europe and their health consequences - A systematic review.

It is well known that meteorological conditions influence the comfort and human health. Southern European countries, including Portugal, show the highest mortality rates during winter, but the effects of extreme cold temperatures in Portugal have never been estimated. The objective of this study was the estimation of the effect of extreme cold temperatures on the risk of death in Lisbon and Oporto, aiming the production of scientific evidence for the development of a real-time health warning system. Poisson regression models combined with distributed lag non-linear models were applied to assess the exposure-response relation and lag patterns of the association between minimum temperature and all-causes mortality and between minimum temperature and circulatory and respiratory system diseases mortality from 1992 to 2012, stratified by age, for the period from November to March. The analysis was adjusted for over dispersion and population size, for the confounding effect of influenza epidemics and controlled for long-term trend, seasonality and day of the week. Results showed that the effect of cold temperatures in mortality was not immediate, presenting a 1-2-day delay, reaching maximum increased risk of death after 6-7days and lasting up to 20-28days. The overall effect was generally higher and more persistent in Lisbon than in Oporto, particularly for circulatory and respiratory mortality and for the elderly. Exposure to cold temperatures is an important public health problem for a relevant part of the Portuguese population, in particular in Lisbon.

Several definitions of bronchopulmonary dysplasia are clinically used; however, their validity remains uncertain considering ongoing changes in the panoply of respiratory support treatment strategies used within neonatal units. To identify the optimal definition of bronchopulmonary dysplasia that best predicts respiratory and neurodevelopmental outcomes in preterm infants. Retrospective cohort study at tertiary neonatal intensive care units. Preterm infants born at less than 29 weeks' gestation between 2010 and 2011 who were admitted to neonatal intensive care units participating in the Canadian Neonatal Network and completed follow-up assessments in a Canadian Neonatal Follow-Up Network clinic at 18 to 21 months. Various traditional bronchopulmonary dysplasia criteria based on respiratory status at different postmenstrual ages. Serious respiratory morbidity, neurosensory impairment at 18 to 21 months of age, and a composite outcome of respiratory or neurosensory morbidity or death after discharge. Adjusted odds ratios (AORs) and 95% CIs were calculated. Of 1914 eligible survivors, 1503 were assessed (mean gestational age was 26.3 weeks; 68% were white, 9% were black, and 23% were other race/ethnicity), 88 had serious respiratory morbidity, 257 infants had neurosensory impairment, and 12 infants died after discharge. Definitions using oxygen requirement alone as the criterion at various postmenstrual ages were less predictive compared with those using the criterion of oxygen/respiratory support (RS) (receiving supplemental oxygen and/or positive-pressure RS); among those, oxygen/RS at 36 weeks had the highest AOR and area under the curve (AUC) for all outcomes. Further analyses of oxygen/RS at each week between 34 and 44 weeks' postmenstrual age indicated that the predictive ability for serious respiratory morbidity increased from 34 weeks (AOR, 1.8; 95% CI, 0.9-3.4, AUC, 0.721) to 40 weeks (AOR, 6.1; 95% CI, 3.4-11.0; AUC, 0.799). For serious neurosensory impairment, the AOR and AUC at 40 weeks' PMA (AOR, 1.5, 95% CI, 1.0-2.1; AUC, 0.740) were only marginally below their peak values at 37 weeks' PMA (AOR, 1.8; 95% CI, 1.3-2.6; AUC, 0.743). Defining bronchopulmonary dysplasia by the use of oxygen alone is inadequate because oxygen/RS is a better indicator of chronic respiratory insufficiency. In particular, oxygen/RS at 40 weeks' PMA was identified as the best predictor for serious respiratory morbidity, while it also displayed a good ability to predict neurosensory morbidity at 18 to 21 months.

BackgroundOxidative stress plays a key role in the pathogenesis of respiratory diseases; however, studies on antioxidant vitamins and respiratory outcomes have been conflicting. We evaluated whether lower serum levels of vitamins A, C, D, and E are associated with respiratory morbidity and mortality in the U.S. adult population.MethodsWe conducted a pooled analysis of data from the 1988–1994 and 1999–2006 National Health and Nutrition Examination Survey (participants aged ≥ 20 years). We estimated covariate-adjusted odds ratios (aOR) per interquartile decrease in each serum vitamin level to quantify associations with respiratory morbidity, and covariate-adjusted hazard ratios (aHR) to quantify associations with respiratory mortality assessed prospectively through 2015. Vitamin supplementation and smoking were evaluated as potential effect modifiers.ResultsLower serum vitamin C increased the odds of wheeze among all participants (overall aOR: 1.08, 95% CI: 1.01–1.16). Among smokers, lower serum α-tocopherol vitamin E increased the odds of wheeze (aOR: 1.11, 95% CI: 1.04–1.19) and chronic bronchitis/emphysema (aOR: 1.13, 95% CI: 1.03–1.24). Conversely, lower serum γ-tocopherol vitamin E was associated with lower odds of wheeze and chronic bronchitis/emphysema (overall aORs: 0.85, 95% CI: 0.79–0.92 and 0.85, 95% CI: 0.76–0.95, respectively). Lower serum vitamin C was associated with increased chronic lower respiratory disease (CLRD) mortality in all participants (overall aHR: 1.27, 95% CI: 1.07–1.51), whereas lower serum 25-hydroxyvitamin D (25-OHD) tended to increase mortality from CLRD and influenza/pneumonia among smokers (aHR range: 1.33–1.75). Mortality from influenza/ pneumonia increased with decreasing serum vitamin A levels in all participants (overall aHR: 1.21, 95% CI: 0.99–1.48). In pooled analysis, vitamin C deficiency and 25-OHD insufficiency were associated with mortality from influenza/pneumonia, increasing mortality risk up to twofold.ConclusionsOur analysis of nationally representative data on over 34,000 participants showed that lower serum levels of vitamins A, C, D, and α-tocopherol vitamin E are associated with increased respiratory morbidity and/or mortality in U.S. adults. The results underscore the importance of antioxidant vitamins in respiratory health.

ISEE-657 Objective: The impact of air pollution in health was studied for some years. The knowledge acquired from this years related Cardiovascular and Respiratory mortality and morbidity to exposure to Particulate Matter (PM10) was continually growing. Nevertheless, the effects of PM10 on Cardiovascular and Respiratory mortality in adults are not well understood in Puerto Rico. The aim of this study was to evaluate the relationship between cardiovascular and respiratory 6 days accumulated deaths and the standardized PM10 levels for all the Puerto Rico municipalities who had PM10 monitoring stations in 1997 and 1998. Materials and Methods: An ecological study was done using mortality data from Puerto Rico Department of Health and PM10 data from Environmental Protection Agency. A Multilevel Poisson Regression Model was performed with 2 levels to consider the time variation in each municipality studied. A ratio of Standardized Mortality Ratio (SMRs) was done to test our objective. Results: Puerto Rico municipalities with high PM10 concentrations (>50 μg/m3) had higher SMRs for cardiovascular and respiratory mortality than those with smaller PM10 concentrations (<50 μg/m3). Cataño and Guaynabo Municipalities had the higher SMRs (P <0.05) for cardiovascular mortality in adults above 65 years. After adjusting for municipality, we compared PM10 levels and cardiovascular mortality. We found in the 65 years and older group, that cardiovascular diseases presented a mean mortality excess of 9% (95% CI: 1%–17%). In the respiratory deaths, we founded that the excess in the mortality was 31% [95% CI: 2%–68%] in the 18–64 years group. Conclusions: We found a mean cardiovascular mortality excess of 9% in the 65 years or older group of the municipalities studied. In addition, we found a mean respiratory mortality excess of 31% in the 18–64 years group. Our findings document consistency and coherence with other published epidemiological studies.

Impacts of cold and hot temperatures on mortality rate in Isfahan, Iran.

Epidemiological research suggests that air pollution may cause chronic diseases, as well as exacerbation of related pathologies such as cardiovascular and respiratory morbidity and mortality. This study evaluates air pollution scenarios considering a Health Impact Assessment approach in São Paulo, Brazil. We have analyzed abatement scenarios of Particulate Matter (PM) with an aerodynamic diameter <10 μm (PM10), <2.5 μm (PM2.5) and ozone concentrations and the health effects on respiratory and cardiovascular morbidity and mortality in the period from 2009 to 2011 through the APHEKOM tool, as well as the associated health costs. Considering World Health Organization (WHO) standards of PM2.5 (10 μg/m3), São Paulo would avoid more than 5012 premature deaths (equivalent to 266,486 life years’ gain) and save US$15.1 billion annually. If São Paulo could even diminish the mean of PM2.5 by 5 μg/m3, nearly 1724 deaths would be avoided, resulting in a gain of US$ 4.96 billion annually. Reduced levels of PM10, PM2.5 and ozone could save lives and an impressive amount of money in a country where economic resources are scarce. Moreover, the reduced levels of air pollution would also lower the demand for hospital care, since hospitalizations would diminish. In this sense, Brazil should urgently adopt WHO air pollution standards in order to improve the quality of life of its population.