Ambient temperature from satellite-hybrid models and preterm birth: A time-stratified case-crossover analysis of 70,000+ preterm births in Central Mexico

Objective. To quantify the association between heat and infant mortality and identify factors that influence infant vulnerability to heat. Methods. We conducted a time-stratified case–crossover analysis of associations between ambient temperature and infant mortality in Philadelphia, Pennsylvania, during the warm months of 2000 through 2015. We used conditional logistic regression models to estimate associations of infant mortality with daily temperatures on the day of death (lag 0) and for averaging periods of 0 to 1 to 0 to 3 days before the day of death. We explored modification of associations by individual and census tract–level characteristics and by amounts of green space. Results. Risk of infant mortality increased by 22.4% (95% confidence interval [CI] = 5.0%, 42.6%) for every 1°C increase in minimum daily temperature over 23.9°C on the day of death. We observed limited evidence of effect modification across strata of the covariates. Conclusions. Our results contribute to a growing body of evidence that infants are a subpopulation that is particularly vulnerable to climate change effects. Further research using large data sets is critically needed to elucidate modifiable factors that may protect infants against heat vulnerability.

Download Full-text

The effect of ambient temperature on type-2-diabetes: case-crossover analysis of 4+ million GP consultations across England

Environmental Health ◽

10.1186/s12940-017-0284-7 ◽

2017 ◽

Vol 16 (1) ◽

Cited By ~ 17

Author(s):

S. Hajat ◽

A. Haines ◽

C. Sarran ◽

A. Sharma ◽

C. Bates ◽

...

Keyword(s):

Type 2 Diabetes ◽

Ambient Temperature ◽

Diabetes Case ◽

Case Crossover ◽

Crossover Analysis

Download Full-text

Evaluating the suitability of the case-crossover design under changing baseline outcome risk: A simulation of ambient temperature and preterm birth

10.1101/2021.02.17.21251948 ◽

2021 ◽

Author(s):

Daniel Carrión ◽

Johnathan Rush ◽

Elena Colicino ◽

Allan C. Just

Keyword(s):

New York ◽

Preterm Birth ◽

Ambient Temperature ◽

Conditional Logistic Regression ◽

New York State ◽

Control Period ◽

Baseline Risk ◽

Absolute Difference ◽

Case Crossover ◽

Time Invariant

AbstractCase-crossover (CCO) studies are case-only within-person analyses of associations between acute exposures and outcomes. By design, the CCO is not confounded by time-invariant characteristics. CCO studies assume stable baseline outcome risks. Since the baseline risk of birth increases secularly over gestation, the validity of CCOs of preterm birth (PTB) is not clear. We simulated associations between temperature and PTB in New York State using historical ambient temperature data for LaGuardia Airport and PTB data from the CDC using different control period durations. CCO analyses were conducted with conditional logistic regression. We calculated bias according to the absolute difference between the simulated and estimated effects in the natural log scale and found that 1-month stratified control period selection yielded bias away from the null across all simulated effects (median = 0.018, IQR: 0.010 − 0.026). In contrast, the 2-week stratification resulted in negligible bias (median: 0.001, IQR: −0.011 − 0.012). Coverage of the 95% confidence intervals decreased with higher effects for the 1-month stratification, with a range 17-87% of estimated intervals including the simulated effect. 2-week stratification had consistent coverage across models (range 95-96%). Our findings suggest that future studies should consider using shorter time strata for PTB.

Download Full-text

Suicide and Ambient Temperature in East Asian Countries: A Time-Stratified Case-Crossover Analysis

Environmental Health Perspectives ◽

10.1289/ehp.1409392 ◽

2016 ◽

Vol 124 (1) ◽

pp. 75-80 ◽

Cited By ~ 47

Author(s):

Yoonhee Kim ◽

Ho Kim ◽

Yasushi Honda ◽

Yue Leon Guo ◽

Bing-Yu Chen ◽

...

Keyword(s):

Ambient Temperature ◽

East Asian ◽

Asian Countries ◽

Case Crossover ◽

Crossover Analysis

Download Full-text

Faculty Opinions recommendation of Atrial Fibrillation Burden and Short-Term Risk of Stroke: Case-Crossover Analysis of Continuously Recorded Heart Rhythm From Cardiac Electronic Implanted Devices.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.725640831.793514215 ◽

2016 ◽

Author(s):

Scott Kasner

Keyword(s):

Atrial Fibrillation ◽

Heart Rhythm ◽

Short Term ◽

Case Crossover ◽

Crossover Analysis ◽

Atrial Fibrillation Burden ◽

Stroke Case ◽

Implanted Devices

Download Full-text

A birth population-based survey of preterm morbidity and mortality by gestational age

BMC Pregnancy and Childbirth ◽

10.1186/s12884-021-03726-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Xiaojing Guo ◽

Xiaoqiong Li ◽

Tingting Qi ◽

Zhaojun Pan ◽

Xiaoqin Zhu ◽

...

Keyword(s):

Birth Weight ◽

Preterm Birth ◽

Preterm Infants ◽

Birth Defects ◽

Gestational Age ◽

Death Rate ◽

Preterm Births ◽

Mortality Rates ◽

Morbidity And Mortality ◽

Hospital Death

Abstract Background Despite 15–17 millions of annual births in China, there is a paucity of information on prevalence and outcome of preterm birth. We characterized the outcome of preterm births and hospitalized preterm infants by gestational age (GA) in Huai’an in 2015, an emerging prefectural region of China. Methods Of 59,245 regional total births, clinical data on 2651 preterm births and 1941 hospitalized preterm neonates were extracted from Huai’an Women and Children’s Hospital (HWCH) and non-HWCH hospitals in 2018–2020. Preterm prevalence, morbidity and mortality rates were characterized and compared by hospital categories and GA spectra. Death risks of preterm births and hospitalized preterm infants in the whole region were analyzed with multivariable Poisson regression. Results The prevalence of extreme, very, moderate, late and total preterm of the regional total births were 0.14, 0.53, 0.72, 3.08 and 4.47%, with GA-specific neonatal mortality rates being 44.4, 15.8, 3.7, 1.5 and 4.3%, respectively. There were 1025 (52.8% of whole region) preterm admissions in HWCH, with significantly lower in-hospital death rate of inborn (33 of 802, 4.1%) than out-born (23 of 223, 10.3%) infants. Compared to non-HWCH, three-fold more neonates in HWCH were under critical care with higher death rate, including most extremely preterm infants. Significantly all-death risks were found for the total preterm births in birth weight < 1000 g, GA < 32 weeks, amniotic fluid contamination, Apgar-5 min < 7, and birth defects. For the hospitalized preterm infants, significantly in-hospital death risks were found in out-born of HWCH, GA < 32 weeks, birth weight < 1000 g, Apgar-5 min < 7, birth defects, respiratory distress syndrome, necrotizing enterocolitis and ventilation, whereas born in HWCH, antenatal glucocorticoids, cesarean delivery and surfactant use decreased the death risks. Conclusions The integrated data revealed the prevalence, GA-specific morbidity and mortality rate of total preterm births and their hospitalization, demonstrating the efficiency of leading referral center and whole regional perinatal-neonatal network in China. The concept and protocol should be validated in further studies for prevention of preterm birth.

Download Full-text