Publications by authors named "Huichu Li"
The circadian rhythm regulates many crucial physiological processes, impacting human aging and aging-related outcomes. Observational evidence links circadian rhythm disturbance to PM exposure, yet the underlying DNA methylation mechanisms remain unclear due to limited PM-dominated experimental settings. Therefore, we investigated the associations between short-term PM exposure and DNA methylation changes of 1188 CpG candidates across circadian genes among 32 young adults in the FDU study, with the validation in 26 individuals from the PKU study.
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- Polycystic ovary syndrome (PCOS) is a common condition that causes irregular menstrual cycles and is linked to cardiovascular and metabolic issues, but more research is needed on its specific relationships and interventions.
- The study aimed to analyze how PCOS, time to menstrual regularity from menarche, and irregular cycles impact the occurrence of various cardiometabolic conditions in participants using the Apple Research app.
- The research involved a large group of US-based individuals, finding that 12.3% had PCOS, with a focus on various cardiovascular and metabolic health outcomes, while also considering how lifestyle factors may influence these associations.
The updated climate models provide projections at a fine scale, allowing us to estimate health risks due to future warming after accounting for spatial heterogeneity. Here, we utilized an ensemble of high-resolution (25 km) climate simulations and nationwide mortality data from 306 Chinese cities to estimate death anomalies attributable to future warming. Historical estimation (1986-2014) reveals that about 15.
View Article and Find Full Text PDFBackground: Menstrual cycle tracking apps (MCTAs) have potential in epidemiological studies of women's health, facilitating real-time tracking of bleeding days and menstrual-associated signs and symptoms. However, information regarding the characteristics of MCTA users versus cycle nontrackers is limited, which may inform generalizability.
Objective: We compared characteristics among individuals using MCTAs (app users), individuals who do not track their cycles (nontrackers), and those who used other forms of menstrual tracking (other trackers).
Background: While studies suggest impacts of individual environmental exposures on type 2 diabetes (T2D) risk, mechanisms remain poorly characterized. Glycated hemoglobin (HbA1c) is a biomarker of glycemia and diagnostic criterion for prediabetes and T2D. We explored associations between multiple environmental exposures and HbA1c in non-diabetic adults.
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- This study analyzed menstrual cycle length and variability using data from over 165,000 cycles tracked by 12,608 participants in the US.
- It found that menstrual cycles tend to shorten with age until around 50, after which they lengthen, and that cycles are longer on average for Asian and Hispanic women compared to white women.
- Additionally, participants with higher body weight (BMI ≥ 40 kg/m) exhibited longer and more variable menstrual cycles, particularly those aged under 20 and over 50, highlighting the need for further research into the factors affecting menstrual health.
Background: Exposure to traffic-related air pollution (TRAP) has been associated with increased risks of respiratory diseases, but the biological mechanisms are not yet fully elucidated.
Objectives: Our aim was to evaluate the respiratory responses and explore potential biological mechanisms of TRAP exposure in a randomized crossover trial.
Methods: We conducted a randomized crossover trial in 56 healthy adults.
Article Synopsis
- The study investigates the link between hourly air pollution levels and the onset of acute symptomatic arrhythmias in China from 2015 to 2021, utilizing a nationwide case-crossover approach.
- Data was collected from over 190,000 patients and includes hourly air quality measurements of six pollutants, highlighting significant associations between increased pollution and higher incidences of atrial fibrillation, atrial flutter, and supraventricular tachycardia shortly after exposure.
- The results show a clear increased risk of arrhythmias associated with air pollution, particularly within the first 24 hours, with no clear threshold levels indicating a safe exposure limit.
Background: Previous studies have linked environmental exposures with anti-Müllerian hormone (AMH), a marker of ovarian reserve. However, associations with multiple environment factors has to our knowledge not been addressed.
Methods: We included a total of 2,447 premenopausal women in the Nurses' Health Study II (NHSII) who provided blood samples during 1996-1999.
Article Synopsis
- The study investigated abnormal uterine bleeding patterns by analyzing menstrual tracking data while considering demographic and health factors.
- It included participants from the Apple Women's Health Study, focusing on individuals who weren't pregnant, breastfeeding, using hormones, or menopausal, and confirmed the accuracy of their tracking.
- Results showed that 16.4% of participants experienced some form of abnormal bleeding, with specific prevalence rates for irregular, infrequent, prolonged menses, and spotting, noting a significantly higher prevalence among Black participants.
COVID-19 vaccination may be associated with change in menstrual cycle length following vaccination. We estimated covariate-adjusted differences in mean cycle length (MCL), measured in days, between pre-vaccination cycles, vaccination cycles, and post-vaccination cycles within vaccinated participants who met eligibility criteria in the Apple Women's Health Study, a longitudinal mobile-application-based cohort of people in the U.S.
View Article and Find Full Text PDFAir pollution has been linked with sleep disturbance in adults, but the association in children remains unclear. To examine the associations of prenatal and postnatal exposure to fine particulate matter (particulate matter ⩽2.5 μm in aerodynamic diameter; PM) with sleep quality and sleep disturbances among children in 551 Chinese cities.
View Article and Find Full Text PDFBackground: Pulmonary embolism (PE) is an important cause of death and its seasonality has long been observed. Very few epidemiological studies have explored the potential role of ambient temperature in PE symptom onset, especially at the hourly level.
Methods: We conducted a time-stratified case-crossover study among 17,903 PE patients with hourly onset of symptom from 1590 hospitals across China between January 2015 and September 2020.
Article Synopsis
- Acute aortic dissection (AAD) is a serious and potentially fatal cardiovascular condition, making it crucial to identify its modifiable risk factors, particularly related to temperature changes.
- A nationwide study in China analyzed data from over 40,000 AAD cases to explore the relationship between low temperatures and fluctuations in daily temperature on the risk of AAD onset, finding significant risks associated with these factors.
- Results indicated that low temperatures were linked to 23.13% of AAD cases, with central heating appearing to reduce this risk during colder months, showcasing the importance of temperature control in public health strategies.
Background: Traffic-related air pollution (TRAP) has been associated with changes in gene-specific DNA methylation. However, few studies have investigated impact of TRAP exposure on genome-wide DNA methylation in circulating blood of human.
Objective: To explore the association between TRAP exposure and genome-wide DNA methylation.
Article Synopsis
- A study analyzed the impact of COVID-19 vaccination on menstrual cycle length using data from 14,915 participants in the Apple Women's Health Study who actively tracked their cycles and completed a vaccine update survey.
- The research included a total of 128,094 menstrual cycles from both vaccinated (8,486) and unvaccinated (1,166) participants, evaluating changes in cycle length before and after vaccination while controlling for factors like hormonal contraceptive use and pregnancy.
- Results indicated no significant difference in the average menstrual cycle length between vaccinated and unvaccinated participants prior to vaccination, suggesting that vaccination did not affect menstrual cycles in this cohort.
Background: The associations of ambient temperature with acute myocardial infarction (AMI) have seldom been examined based on the time of symptom onset.
Methods: We conducted a time-stratified case-crossover study among 1,046,773 eligible AMI patients from 2,093 hospitals in 324 Chinese cities from January 1, 2015 to June 30, 2021, after excluding those transferred from other hospitals or having not reported the time of symptom onset. Hourly exposure to ambient temperature was calculated as multiple moving 24-h averages (days) before hourly onset of AMI symptoms.
Article Synopsis
- A study investigated the cardiovascular effects of traffic-related air pollution (TRAP) in 56 young adults by comparing their health during two different exposure sessions: one near a busy road and the other in a park.
- Participants showed higher levels of pollution while exposed to TRAP, particularly in terms of black carbon and nitrogen dioxide, leading to elevated blood pressure and decreased heart rate variability (HRV).
- The research revealed various molecular changes linked to inflammation and cardiovascular health, suggesting that reducing TRAP could be important for heart health.
Background: Short-term exposure to ambient air pollution has been linked with daily hospitalization and mortality from acute coronary syndrome (ACS); however, the associations of subdaily (hourly) levels of criteria air pollutants with the onset of ACS and its subtypes have rarely been evaluated.
Methods: We conducted a time-stratified case-crossover study among 1 292 880 patients with ACS from 2239 hospitals in 318 Chinese cities between January 1, 2015, and September 30, 2020. Hourly concentrations of fine particulate matter (PM), coarse particulate matter (PM), nitrogen dioxide (NO), sulfur dioxide (SO), carbon monoxide (CO), and ozone (O) were collected.
Exposure to fine particulate matter (PM) during pregnancy has been linked to the risk of gestational diabetes mellitus (GDM), while conclusions are inconsistent. In this study we aimed to estimate the effects of prenatal PM exposure with blood glucose in early pregnancy and the GDM risk. Participants were recruited from the SH-IPMCH-BTH cohort (n = 41,929), a study of air pollution and birth outcome.
View Article and Find Full Text PDFEpidemiological studies have associated ozone exposure with cardiovascular diseases, but the molecular mechanisms were not elucidated. We performed an untargeted serum proteomic analysis in a randomized, crossover, controlled exposure trial. We recruited 32 healthy young adults and asked them to receive filtered air and 200-ppb ozone exposures for 2 h in a random order before serum collection.
View Article and Find Full Text PDFBackground: Potential hazards of fine particulate matter (PM) constituents on preterm birth (PTB) have rarely been explored in China.
Objective: To quantify the associations of PM constituents with PTB.
Methods: This study was based on a nationwide cohort of 3,723,169 live singleton births delivered between January 2010 and December 2015 in China.
Aims: The incidence of acute aortic dissection (AAD) has been shown to have seasonal variation, but whether this variation can be explained by non-optimum ambient temperature and temperature change between neighbouring days (TCN) is not clear.
Methods And Results: We performed a time-stratified case-crossover study in the Registry of Aortic Dissection in China covering 14 tertiary hospitals in 11 cities from 2009 to 2019. A total of 8182 cases of AAD were included.