24-Hour warning signs for adolescent suicide attempts.

BACKGROUND: Little is known about when youth may be at greatest risk for attempting suicide, which is critically important information for the parents, caregivers, and professionals who care for youth at risk. This study used adolescent and parent reports, and a case-crossover, within-subject design to identify 24-hour warning signs (WS) for suicide attempts. METHODS: Adolescents (N = 1094, ages 13 to 18) with one or more suicide risk factors were enrolled and invited to complete bi-weekly, 8-10 item text message surveys for 18 months. Adolescents who reported a suicide attempt (survey item) were invited to participate in an interview regarding their thoughts, feelings/emotions, and behaviors/events during the 24-hours prior to their attempt (case period) and a prior 24-hour period (control period). Their parents participated in an interview regarding the adolescents' behaviors/events during these same periods. Adolescent or adolescent and parent interviews were completed for 105 adolescents (81.9% female; 66.7% White, 19.0% Black, 14.3% other). RESULTS: Both parent and adolescent reports of suicidal communications and withdrawal from social and other activities differentiated case and control periods. Adolescent reports also identified feelings (self-hate, emotional pain, rush of feelings, lower levels of rage toward others), cognitions (suicidal rumination, perceived burdensomeness, anger/hostility), and serious conflict with parents as WS in multi-variable models. CONCLUSIONS: This study identified 24-hour WS in the domains of cognitions, feelings, and behaviors/events, providing an evidence base for the dissemination of information about signs of proximal risk for adolescent suicide attempts.

Seasonal extreme temperatures and short-term fine particulate matter increases pediatric respiratory healthcare encounters in a sparsely populated region of the intermountain western United States.

BACKGROUND: Western Montana, USA, experiences complex air pollution patterns with predominant exposure sources from summer wildfire smoke and winter wood smoke. In addition, climate change related temperatures events are becoming more extreme and expected to contribute to increases in hospital admissions for a range of health outcomes. Evaluating while accounting for these exposures (air pollution and temperature) that often occur simultaneously and may act synergistically on health is becoming more important. METHODS: We explored short-term exposure to air pollution on children's respiratory health outcomes and how extreme temperature or seasonal period modify the risk of air pollution-associated healthcare events. The main outcome measure included individual-based address located respiratory-related healthcare visits for three categories: asthma, lower respiratory tract infections (LRTI), and upper respiratory tract infections (URTI) across western Montana for ages 0-17 from 2017-2020. We used a time-stratified, case-crossover analysis with distributed lag models to identify sensitive exposure windows of fine particulate matter (PM2.5) lagged from 0 (same-day) to 14 prior-days modified by temperature or season. RESULTS: For asthma, increases of 1 µg/m3 in PM2.5 exposure 7-13 days prior a healthcare visit date was associated with increased odds that were magnified during median to colder temperatures and winter periods. For LRTIs, 1 µg/m3 increases during 12 days of cumulative PM2.5 with peak exposure periods between 6-12 days before healthcare visit date was associated with elevated LRTI events, also heightened in median to colder temperatures but no seasonal effect was observed. For URTIs, 1 unit increases during 13 days of cumulative PM2.5 with peak exposure periods between 4-10 days prior event date was associated with greater risk for URTIs visits that were intensified during median to hotter temperatures and spring to summer periods. CONCLUSIONS: Delayed, short-term exposure increases of PM2.5 were associated with elevated odds of all three pediatric respiratory healthcare visit categories in a sparsely population area of the inter-Rocky Mountains, USA. PM2.5 in colder temperatures tended to increase instances of asthma and LRTIs, while PM2.5 during hotter periods increased URTIs.

Short-term associations of particulate matter with different aerodynamic diameters with mortality due to mental disorders and dementia in Ningde, China.

Limited evidence is available regarding the impact of ambient inhalable particulate matter (PM) on mental disorder (MD) or dementia-related deaths, particularly PM1, PM1-2.5, and coarse particles (PM2.5-10). Moreover, individual confounders have rarely been considered. In addition, evidence from low-pollution areas is needed but is inadequate. Using death records from the Death Registration System during 2015-2021 in Ningde, a coastal city in southeast China, we combined a conditional quasi-Poisson model with a distributed lag nonlinear model to estimate the nonlinear and lagged associations of PM exposure with MD or dementia-related deaths in Ningde, China, comprehensively controlling for individual time-invariant confounders using a time-stratified case-crossover design. The attributable fraction and number were calculated to quantify the burden of MD or dementia-related deaths that were related to PMs. We found J-shaped relationships between MD or dementia-related deaths and PMs, with different thresholds of 13, 9, 19, 33 and 12 µg/m3 for PM1, PM1-2.5, PM2.5, PM10 and PM2.5-10. An inter-quartile range increase for PM1, PM1-2.5, PM2.5, PM10 and PM2.5-10 above the thresholds led to an increase of 31.8% (95% confidence interval, 14.3-51.9%), 53.7% (22.4-93.1%), 32.6% (15.0-53.0%), 35.1% (17.7-55.0%) and 25.9% (13.0-40.3%) in MD-related deaths at lag 0-3 days, respectively. The associations were significant in the cool season rather than in the warm season and were significantly greater among people aged 75-84 years than in others. The fractions of MD-related deaths attributable to PM1, PM1-2.5, PM2.5, PM10 and PM2.5-10 were 5.55%, 6.49%, 7.68%, 10.66%, and 15.11%, respectively; however, only some of them could be protected by the concentrations recommended by the World Health Organisation or China grade I standard. Smaller associations and similar patterns were observed between PMs and dementia-related death. These findings suggest stricter standards, and provide evidence for the development of relevant policies and measures.

Is short-term exposure to primary gaseous air pollutants associated with AIDS-related deaths? Evidence from a time-stratified case-crossover study.

Primary gaseous air pollutants have been associated with death from multiple causes, however, it remains unknown if they play a role in premature mortality among individuals living with HIV/AIDS. Data on HIV/AIDS patients were collected from the Hubei Provincial Center for Disease Control and Prevention, with a total of 1,467 AIDS-related deaths (ARD) between 2013 and 2020. Daily mean sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO) were generated by artificial intelligence algorithms combined with big data. We employed a time-stratified case-crossover approach and conditional logistical regression models to investigate the acute effects of primary gaseous air pollutants on ARD. Per interquartile range increase in the concentrations of SO2 was significantly linked with ARD, with a corresponding odds ratio (OR) of 1.17 [95% confidence intervals (CIs): 1.01, 1.35] at lag 4 day. Furthermore, our findings indicated that males exhibited a heightened vulnerability to the adverse effects of SO2 and NO2, for example, the ORs were 1.24 (95% CIs: 1.05, 1.47) and 1.16 (95% CIs: 1.01, 1.34), respectively. Moreover, individuals aged over 65 years were more susceptible to SO2 and CO. Additionally, we identified the warm season as a sensitive period for mortality associated with SO2 and NO2. Our study furnished fresh evidence regarding the detrimental effects of primary gaseous air pollutants on ARD.

Association of ambient temperature with intentional self-harm and suicide death in Seoul: a case-crossover design with a distributed lag nonlinear model.

Previous epidemiological studies have reported a short-term association between ambient temperature and suicide risk. To gain a clearer understanding of this association, it is essential to differentiate the risk factors for intentional self-harm (ISH) from those specifically associated with suicide deaths. Therefore, this study aims to examine whether the association between daily temperature and ISH or suicide deaths differs by age and sex. Between 2014 and 2019, cases of emergency room visits related to ISH and suicide deaths in Seoul were identified. A time-stratified case-crossover design was used to adjust for temporal trends and seasonal variation. A distributed lag nonlinear model was used to analyze the nonlinear and time-delayed effect of ambient temperature on ISH and suicide deaths. Positive associations were observed between temperature and both ISH and suicide deaths. For ISH, the relative risk (RR) was high at 1.17 (95% confidence interval (CI): 1.03, 1.34) for a temperature of 25.7 °C compared with 14.8 °C. The RR for suicide death was higher than those for ISH, at 1.43 (95% CI: 1.03, 2.00) for a temperature of 33.7 °C. These associations varied by age and sex, with males and females aged 35-64 years showing increased susceptibility to suicide deaths. This study provides detailed evidence that unusually high temperatures, both anomalous and out of season, may trigger suicidal behaviors, including both ISH and suicide deaths.

Association between ambient temperature, PM2.5 and tuberculosis in Northwest China.

Existing evidence suggested that the risk of tuberculosis (TB) infection was associated to the variations in temperature and PM2.5. A total of 9,111 cases of TB were reported in Ningxia Hui Autonomous Region, China from 2013 to 2015 on a daily basis, and 57.2% of them were male. The TB risk was more prominent for a lower temperature in males (RR of 1.724, 95% CI: 1.241, 2.394), the aged over 64 years (RR of 2.241, 95% CI: 1.554, 3.231), and the high mobility occupation subpopulation (RR of 2.758, 95% CI: 1.745, 4.359). High concentration of PM2.5 showed a short-term effect and was only associated with an increased risk in the early stages of exposure for the female, and aged 36-64 years group. There were 15.06% (1370 cases) of cases of TB may be attributable to the temperature, and 2.94% (268 cases) may be attributable to the increase of PM2.5 exposures. Low temperatures may be associated with significantly increase in the risk of TB, and high PM2.5 concentrations have a short-term association on increasing the risk of TB. Strengthening the monitoring and regular prevention and control of high risk groups will provide scientific guidance to reduce the incidence of TB.

Outdoor Alternaria and Cladosporium spores and acute asthma.

BACKGROUND: Outdoor Alternaria and Cladosporium spores are ubiquitous. Few studies have assessed their impact on asthma hospitalizations providing conflicting results, mainly focused on vulnerable paediatric populations. We aimed to study the impact of outdoor Alternaria and Cladosporium concentrations on acute hospitalizations in the Capital Region of Denmark. METHODS: This is a bi-directional case-crossover study with 26 years of national registry data at individual level on acute asthma hospitalizations and daily average data on Alternaria and Cladosporium, pollen (Artemisia, Poaceae), maximal temperature, and air pollution. Conditional logistic regression models were applied to assess the associations. Concentration quartiles at lag 0 were used for categorizing the exposure. RESULTS: For lags 0-2, the odds of hospitalization were significantly higher for both Alternaria and Cladosporium at concentration quartile 2-4 compared with quartile 1. When stratified for age and sex, odds of hospitalization at Alternaria quartiles 2-4 were significantly higher in males below 40 years at lag 0-2, and at lag 0 in females (18-30 years), while quartiles 2-4 of Cladosporium concentrations were associated with significantly higher odds in boys (0-17 years) at lag 1-3, males (18-39 years) at lag 0-1, females (18-39 years) at lag 1-2, males (40-64 years) at lag 0-2, females (40-64 years) at lag 0 and 2, in seniors (65+ years) male at lag 1-2 and female at lag 0-1. The effect of Alternaria varied significantly depending on the level of Cladosporium (p < .0001). CONCLUSION: Ambient Alternaria and Cladosporium spores can induce asthma hospitalizations. Males are more susceptible to both genera. Males and females under age 40 years are more susceptible to Alternaria.

Short-term exposure to ozone and mortality from AIDS-related diseases: A case-crossover study in the middle Yangtze River region, China.

BACKGROUND: Previous investigations have predominantly concentrated on the influence of ozone (O3) on general population mortality. However, a noticeable gap exists regarding the attention directed towards susceptible demographics, specifically individuals afflicted by human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). METHODS: A dataset comprising 1467 AIDS-related fatalities from 2013 to 2020 was amassed from the Hubei Provincial Center for Disease Control and Prevention. Daily maximum 8-h average O3 levels and meteorological parameters were extracted from the ChinaHighAirPollutants dataset and the National Meteorological Science Data Center, respectively. A time-stratified case-crossover methodology was employed to scrutinize the connection between short-term exposure to O3 and AIDS-related deaths. RESULTS: A rise of one interquartile (IQR) in O3 concentration, lagged by 4 days, was associated with a 15% [95% confidence intervals (CIs): 2, 31] increase in AIDS-related deaths. Notably, males demonstrated heightened susceptibility to the adverse consequences of O3, marked by an odds ratio of 1.20 (95% CIs: 1.05, 1.37) at lag 4 day. Additionally, patients aged over 65 years exhibited escalated vulnerability to brief O3 exposure. Marriage status and educational attainment emerged as influential factors modifying the interplay between O3 and AIDS-related mortality. CONCLUSIONS: Our study presents novel evidence spotlighting the deleterious repercussions of O3 on mortality in the HIV/AIDS population.

Residential greenness mitigates mortality risk from short-term airborne particulate exposure: An individual-level case-crossover study.

BACKGROUND: Studies suggested that greenness could reduce death risks related to ambient exposure to particulate matter (PM), while the available evidence was mixed across the globe and substantially exiguous in low- and middle-income countries. By conceiving an individual-level case-crossover study in central China, this analysis primarily aimed to quantify PM-mortality associations and examined the modification effect of greenness on the relationship. METHODS: We investigated a total of 177,058 nonaccidental death cases from 12 counties in central China, 2008-2012. Daily residential exposures to PM2.5 (aerodynamic diameter <2.5 µm), PMc (aerodynamic diameter between 2.5 and 10 µm), and PM10 (aerodynamic diameter <10 µm) were assessed at a 1 × 1-km resolution through satellite-derived machine-learning models. Residential surrounding greenness was assessed using satellite-derived enhanced vegetation index (EVI) and normalized difference vegetation index (NDVI) at multiple buffer sizes (250, 500, and 1000 m). To quantify the acute mortality risks associated with short-term exposure to PM2.5, PMc, and PM10, a time-stratified case-crossover design was utilized in conjunction with a conditional logistic regression model in our main analyses. To investigate the effect modification of greenness on PM-mortality associations, we grouped death cases into low, medium, and high greenness levels using cutoffs of 25th and 75th percentiles of NDVI or EVI exposure, and examined potential effect heterogeneity in PM-related mortality risks among these groups. RESULTS: Mean concentrations (standard deviation) on the day of death were 73.8 (33.4) µg/m3 for PM2.5, 43.9 (17.3) µg/m3 for PMc, and 117.5 (44.9) µg/m3 for PM10. Size-fractional PM exposures were consistently exhibited significant associations with elevated risks of nonaccidental and circulatory mortality. For every increase of 10-µg/m3 in PM exposure, percent excess risks of nonaccidental and circulatory mortality were 0.271 (95% confidence interval [CI]: 0.010, 0.533) and 0.487 (95% CI: 0.125, 0.851) for PM2.5 at lag-01 day, 0.731 (95% CI: 0.108, 1.359) and 1.140 (95% CI: 0.267, 2.019) for PMc at lag-02 day, and 0.271 (95% CI: 0.010, 0.533) and 0.386 (95% CI: 0.111, 0.662) for PM10 at lag-01 day, respectively. Compared to participants in the low-level greenness areas, those being exposed to higher greenness were found to be at lower PM-associated risks of nonaccidental and circulatory mortality. Consistent evidence for alleviated risks in medium or high greenness group was observed in subpopulations of female and younger groups (age <75). CONCLUSIONS: Short-term exposure to particulate air pollution was associated with elevated risks of nonaccidental and circulatory death, and individuals residing in higher neighborhood greenness possessed lower risk of PM-related mortality. These findings emphasized the potential public health advantages through incorporating green spaces into urban design and planning.

Ambient air pollution and epileptic seizures: A panel study in Australia.

OBJECTIVE: Emerging evidence has shown that ambient air pollution affects brain health, but little is known about its effect on epileptic seizures. This work aimed to assess the association between daily exposure to ambient air pollution and the risk of epileptic seizures. METHODS: This study used epileptic seizure data from two independent data sources (NeuroVista and Seer App seizure diary). In the NeuroVista data set, 3273 seizures were recorded using intracranial electroencephalography (iEEG) from 15 participants with refractory focal epilepsy in Australia in 2010-2012. In the seizure diary data set, 3419 self-reported seizures were collected through a mobile application from 34 participants with epilepsy in Australia in 2018-2021. Daily average concentrations of carbon monoxide (CO), nitrogen dioxide (NO2 ), ozone (O3 ), particulate matter ≤10 µm in diameter (PM10 ), and sulfur dioxide (SO2 ) were retrieved from the Environment Protection Authority (EPA) based on participants' postcodes. A patient-time-stratified case-crossover design with the conditional Poisson regression model was used to determine the associations between air pollutants and epileptic seizures. RESULTS: A significant association between CO concentrations and epileptic seizure risks was observed, with an increased seizure risk of 4% (relative risk [RR]: 1.04, 95% confidence interval [CI]: 1.01-1.07) for an interquartile range (IQR) increase of CO concentrations (0.13 parts per million), whereas no significant associations were found for the other four air pollutants in the whole study population. Female participants had a significantly increased risk of seizures when exposed to elevated CO and NO2 , with RRs of 1.05 (95% CI: 1.01-1.08) and 1.09 (95% CI: 1.01-1.16), respectively. In addition, a significant association was observed between CO and the risk of subclinical seizures (RR: 1.20, 95% CI: 1.12-1.28). SIGNIFICANCE: Daily exposure to elevated CO concentrations may be associated with an increased risk of epileptic seizures, especially for subclinical seizures.

Particulate matter and ozone might trigger deaths from chronic ischemic heart disease.

AIMS: To study the association between short-term exposure to air pollutants and mortality of Chronic Ischemic Heart Disease (CIHD). METHODS: Using a case-crossover design, we investigated 148,443 CIHD deaths from 2015 to 2020 in Jiangsu Province, China. Exposure to six ambient pollutants, including PM10, PM2.5, NO2, CO, SO2, and O3, was assessed by extracting daily concentrations from validated 10 km × 10 km pollutant grids at each subject's residential address. A conditional logistic regression approach was used to explore the exposure-response relationship with adjustment for temperature and relative humidity. We calculated the Population Attributable Fractions (PAFs) and the attributable deaths number of CIHD. RESULTS: An increase of 10 µg/m3 in PM10 and PM2.5 exposure was associated with a 1.16% (95% CI: 0.85-1.48%) and 1.80% (1.36-2.24%) increase in CIHD mortality, respectively. A threshold value of 123 µg/m3 was identified for the association between O3 exposure and CIHD mortality. Controlling for PM2.5, each increase of 10 µg/m3 in O3 (>threshold) was statistically significantly associated with a 0.94% (0.19-1.71%) increase in CIHD mortality, however there was no association between NO2, SO2, CO exposure and CIHD mortality. Reducing PM2.5, PM10 and O3 to the WHO air quality guidelines would prevent 6.16% (95% CI: 4.70-7.58%), 4.30% (3.18-5.43%) and 1.29% (0.48-4.20%) of CIHD deaths, respectively. During the warm season, mortality and PAFs of CIHD associated with PM2.5, PM10, and O3 were significantly higher. CONCLUSIONS: Short-term exposure to ambient PM2.5, PM10, and O3 might trigger deaths from CIHD. These findings indicate that the premature deaths of CIHD patients can be alleviated by reducing exposure to polluted air.

Short-term exposure to nitrogen dioxide and ischemic stroke incidence in Shenzhen, China: Modification effects by season and temperature.

BACKGROUND AND OBJECTIVES: China has experienced a serious public health burden because of the increased incidence of ischemic stroke. Evidence describing the association between short-term exposure to nitrogen dioxide (NO2) and ischemic stroke morbidity is limited, and few studies have focused on the effects of season and temperature. This study aimed to evaluate the acute effects of NO2 on ischemic stroke incidence in Shenzhen, a southeastern city of China, considering the modified effects of season and temperature. METHODS: A time-stratified case-crossover study was conducted between 2003 and 2014 among 98,482 ischemic stroke hospitalizations. Conditional quasi-Poisson regression was used to estimate the percentage changes in ischemic stroke admissions in relation to each 10 µg/m3 increment in NO2. RESULTS: NO2 was positively associated with ischemic stroke onset over the full year, as well as in the cold season (November through April) and on cold days (ambient temperature≤median temperature), with significant single-day effects within 3 days after the exposure, and significant cumulative effects within the delayed five days. The maximum percentage changes were obtained at lag0-5, with 1.81% (95% confidence interval (CI) was 0.86-2.76%) over the full year, 2.75% (1.48-4.03%) in the cold season, and 3.04% (1.74-4.35%) on cold days. Additionally, the effects of exposure were found to be greater in males and people with higher education, and were lasting longer in subgroups of older individuals. CONCLUSIONS: Our findings provide evidence that reductions in NO2 levels might decrease ischemic stroke morbidity, and enhance the understanding of ischemic stroke occurrence associated with NO2 modified by season and temperature.

Risk of Intracranial Hemorrhage With Concomitant Use of Antidepressants and Nonsteroidal Anti-inflammatory Drugs: A Nested Case-Control Study.

BACKGROUND: Whereas previous studies found that concomitant antidepressant and nonsteroidal anti-inflammatory drug (NSAIDs) use may increase the risk of gastrointestinal bleeding, either drug alone increases the risk of intracranial hemorrhage (ICH). OBJECTIVE: To assess the risk for ICH in patients on concomitant treatment with antidepressants and NSAIDs. METHODS: This was a nested case-control study using national insurance claims data in Taiwan between 2005 and 2013. Drug exposure was measured and compared during 3 time windows: 1 to 30, 31 to 60, and 61 to 90 days before the index date, which is the date of the ICH event. Both traditional and newer-generation antidepressants were considered in this study. RESULTS: Patients exposed to both antidepressants and NSAIDs 1 to 30 days before the index date presented a 50% increased odds of developing ICH (OR: 1.53; 95% CI: 1.31-1.80) compared with patients receiving antidepressants alone. Specifically, the concomitant use of nonselective NSAIDs and antidepressants increased these odds compared with antidepressants alone (OR: 1.56; 95% CI: 1.31-1.84), but using a selective cyclooxygenase-2 inhibitor with antidepressant did not alter ICH risk. Regarding antidepressant class, newer-generation antidepressants generally increase the odds of developing ICH by 60% when used concomitantly with NSAIDs. CONCLUSION AND RELEVANCE: Our results suggested that the concomitant use of antidepressants and NSAIDs was associated with an increased odds of developing ICH. NSAIDs, especially nonselective NSAIDs, and serotonergic antidepressants played an important role in this risk. Given the prevalent use of these 2 classes of drugs, this potential drug interaction deserves more attention.

Ambient air pollutants and hospital visits for pneumonia: a case-crossover study in Qingdao, China.

BACKGROUND: Pneumonia is one of the principal reasons for incidence and death in the world. The former research mainly concentrated on specific sources of patients. Besides, due to the heterogeneity among regions, there are inconsistencies in the outcome of these surveys. To explore the relationship between atmospheric pollution and hospital visits for pneumonia under the climate and pollution conditions in Qingdao, we carried out this study. METHODS: The medical records of pneumonia patients were gathered from the affiliated hospital of Qingdao University during Jan 1st, 2014, and Dec 31st,2018. Daily concentrations of PM2.5, PM10, SO2, NO2, as well as CO, were collected from the national air quality monitoring stations in Qingdao. Case-crossover study design and conditional logistic regression model were used to estimate the associations. Daily temperature, relative humidity, and atmospheric pressure were adjusted as the covariates in all models. A principal component analysis was used to solve the multicollinearity between atmospheric pollutants and investigate the relationship between various air pollutants and pneumonia occurs. RESULTS: In the single pollutant model, with interquartile range increment of the density of PM2.5, PM10, NO2 and SO2 at the lag2 days, the odds ratio of hospital visits for pneumonia patients increased by 6.4% (95%CI, 2.3-10.7%), 7.7% (95%CI, 3.2-12.4%), 6.7% (95%CI, 1.0-12.7%), and 7.2% (95%CI, 1.1-13.5%). Stratified analysis showed that pollutants were more significant in the cold period. Besides, the impact of atmospheric particulates on different ages mainly occurs in the young child (0 to 3-year-old). The odds ratio was 1.042 (95%CI, 1.012-1.072) when the principal components of atmospheric pollutants were included in the conditional logistic model. CONCLUSIONS: Our study found a significant relationship between short-term uncovering to PM2.5, PM10, NO2, SO2, and hospital visits for pneumonia in Qingdao. The effect of atmospheric pollutants mainly arose in a cold period. The particulate matter might be the principal reason in inducing hospital visits for pneumonia.

Identifying drug combinations associated with acute kidney injury using association rules method.

BACKGROUND: Older adults are at an increased risk of acute kidney injury (AKI) because of aging, multiple comorbidities, and polypharmacy. OBJECTIVES: The aim of this case-crossover study was to apply association rule (AR) analysis to ascertain drug combinations contributing to the risk of AKI in adults aged 65 years and older. METHODS: We sourced a nationwide representative sample of New Zealanders aged ≥65 years from the pharmaceutical collections and hospital discharge information. Prescription records (2005-2015) of drugs of interest were sourced from New Zealand pharmaceutical collections (Pharms). We classified medication exposure, as a binary variable, at individual drug level belonging to medication classes including antimicrobials, antihistamines, diuretics, opioids, nonsteroidal anti-inflammatory medications. Several studies have associated the drugs of interest from these medication classes with AKI in older adults. We extracted the first-time coded diagnosis of AKI from the National Minimal Data Set. A unique patient identifier linked the prescription data set to the event data set, to set up a case-crossover cohort, indexed at the first AKI event. ARs were then applied to identify frequent drug combinations in the case and the control periods (l-day observation with a 35-day washout period), and the association of AKI with each frequent drug combination was tested by computing a matched odds ratio (MOR) and its 95% confidence interval (CI). RESULTS: We identified 55 747 individuals (mean age 82.14) from 2005 to 2014 with incident AKI and exposed to at least one of the drugs of interest. ARs identified several medication classes including antimicrobials, nonsteroidal anti-inflammatory drugs, and opioids are associated with AKI. The frequently used medicines associated with AKI are trimethoprim (MOR = 1.68; 95% CI = [1.54-1.80]), ondansetron (MOR = 1.43; 95% CI = [1.25-1.64]), codeine phosphate plus metoclopramide (MOR = 1.37; 95% CI = [1.11-1.63]), and norfloxacin (MOR = 1.24; 95% CI [1.05-1.42]). CONCLUSIONS: We applied ARs, a novel methodology, to big data to ascertain drug combinations associated with AKI. ARs uncovered previously implicated medication classes that increase the risk of AKI in older adults. The finding that ondansetron increases the risk of AKI requires further investigation.

High ambient temperature in summer and risk of stroke or transient ischemic attack: A national study in Israel.

OBJECTIVE: To examine whether high ambient temperature and diurnal temperature range during the summer are associated with risk of stroke/transient ischemic attack (TIA). METHODS: A time-stratified case-crossover study design was conducted. The study sample comprised all individuals aged ≥50 years who had a stroke/TIA reported to the Israeli National Stroke Registry between 2014 and 2016 during the summer season. Daily temperature data were retrieved from the Israel Meteorological Service. Conditional logistic regression models were used with relative humidity and air pollution as covariates. RESULTS: The sample included 15,123 individuals who had a stroke/TIA during the summer season (mean age 73 ± 12 years; 54% males). High ambient temperature was associated with stroke/TIA risk starting from the day before the stroke event, and increasing in strength over a six-day lag (OR = 1.10 95%CI 1.09-1.12). Moreover, a larger diurnal temperature range prior to stroke/TIA occurrence was associated with decreased stroke/TIA risk (OR = 0.96 95%CI 0.95-0.97 for a six-day lag). CONCLUSIONS: High ambient temperature may be linked to increased risk of cerebrovascular events in subsequent days. However, relief from the heat during the night may attenuate this risk.

Association between short-term exposure to air pollution and ischemic stroke onset: a time-stratified case-crossover analysis using a distributed lag nonlinear model in Shenzhen, China.

BACKGROUND: Stroke, especially ischemic stroke (IS), has been a severe public health problem around the world. However, the association between air pollution and ischemic stroke remains ambiguous. METHODS: A total of 63, 997 IS cases aged 18 years or above in Shenzhen were collected from 2008 to 2014. We used the time-stratified case-crossover design combining with distributed lag nonlinear model (DLNM) to estimate the association between air pollution and IS onset. Furthermore, this study explored the variability across gender and age groups. RESULTS: The cumulative exposure-response curves were J-shaped for SO2, NO2 and PM10, and V-shaped for O3, and crossed over the relative risk (RR) of one. The 99th, 50th (median) and 1st percentiles of concentration (µg/m3) respectively were 37.86, 10.06, 3.71 for SO2, 116.26, 41.29, 18.51 for NO2, 145.94, 48.29, 16.14 for PM10, and 111.57, 49.82, 16.00 for O3. Extreme high-SO2, high-NO2, high-PM10, high-O3, and low-O3 concentration increased the risk of IS, with the maximum RR values and 95% CIs: 1.50(1.22, 1.84) (99th vs median) at 0-12 lag days, 1.37(1.13, 1.67) (99th vs median) at 0-10 lag days, 1.26(1.04, 1.53) (99th vs median) at 0-12 lag days, 1.25(1.04, 1.49) (99th vs median) at 0-14 lag days, and 1.29(1.03, 1.61) (1st vs median) at 0-14 lag days, respectively. The statistically significant minimal RR value and 95% CI was 0.79(0.66,0.94) at 0-10 lag days for extreme low-PM10. The elderly aged over 65 years were susceptible to extreme pollution conditions. Difference from the vulnerability of males to extreme high-SO2, high-NO2 and low-O3, females were vulnerable to extreme high-PM10 and high-O3. Comparing with the elderly, adults aged 18-64 year were immune to extreme low-NO2 and low-PM10. However, no association between CO and IS onset was found. CONCLUSIONS: SO2, NO2, PM10 and O3 exerted non-linear and delayed influence on IS, and such influence varied with gender and age. These findings may have significant public health implications for the prevention of IS.

Short-term effects of air pollution on exacerbations of allergic asthma in Uzice region, Serbia.

INTRODUCTION: Many time-series studies have shown a positive association between air pollution and asthma exacerbation. However, till now only one study in Serbia has examined this relationship. AIM: To examine the associations between air pollution and asthma emergency department (ED) visits in the Uzice region, Serbia. MATERIAL AND METHODS: A time-stratified case-crossover design was applied to 424 ED visits for asthma exacerbation that occurred in the Uzice region, Serbia, in 2012-2014. Data about ED visits were routinely collected in the Uzice Health Centre. The daily average concentrations of particulate matter (PM2.5 and PM10), sulphur dioxide (SO2), nitrogen dioxide (NO2), and black carbon (BC) were measured by automatic ambient air quality monitoring stations. Odds ratios and their corresponding 95% confidence intervals were estimated using conditional logistic regression adjusted for the potential confounding influence of weather variables (temperature, humidity and air pressure). RESULTS: Statistically significant associations were observed between ED visits for asthma and 3-day lagged exposure to BC (OR = 3.23; 95% CI: 1.05-9.95), and between ED visits for asthma with coexisting allergic rhinitis and 0-day lag exposure to NO2 (OR = 1.57; 95% CI: 0.94-2.65), 2-day lag exposure to SO2 (OR = 1.97; 95% CI: 1.02-3.80), and 3-day lag exposure to PM10 (OR = 2.38; 95% CI: 1.17-4.84). CONCLUSIONS: Exposure to ambient air pollution in the Uzice region increases the risk of ED visits for asthma, particularly during the heating season.

Relation of outbursts of anger and the acute risk of placental abruption: A case-crossover study.

BACKGROUND: Roughly, a fourth of all placental abruption cases have an acute aetiologic underpinning, but the causes of acute abruption are poorly understood. Studies indicate that symptoms of stress, depression, and anxiety during pregnancy may be associated with a higher risk of abruption. OBJECTIVE: We examined the rate of abruption in the 2 hours immediately following outbursts of anger. METHODS: In a multicentre case-crossover study, we interviewed 663 women diagnosed with placental abruption admitted to one of the seven Peruvian hospitals between January 2013 and August 2015. We asked women about outbursts of anger before symptom onset and compared this with their usual frequency of anger during the week before abruption. RESULTS: The rate of abruption was 2.83-fold (95% confidence interval [CI] 1.85, 4.33) higher in the 2 hours following an outburst of anger compared with other times. The rate ratio (RR) was lower for women who completed technical school or university (RR 1.38, 95% CI 0.52, 3.69) compared to women with secondary school education or less (RR 3.73, 95% CI 2.32, 5.99, P-homogeneity = .07). There was no evidence that the association between anger episodes and abruption varied by hypertensive disorders of pregnancy (ie preeclampsia/ eclampsia) or antepartum depressive symptoms. CONCLUSION: There was a higher rate of abruption in the 2 hours following outbursts of anger compared with other times, providing potential clues to the aetiologic mechanisms of abruption of acute onset.

Proton-pump inhibitors and the risk of Clostridium difficile-associated diarrhea in high-risk antibiotics users: A population-based case-crossover study.

PURPOSE: Given the severity and high-costs demand of Clostridium difficile-associated diarrhea (CDAD), management of risk factors is very important. Although the association between proton-pump inhibitors (PPIs) and CDAD has been established, little is known among high-risk antibiotics users. This study aimed to identify the association between PPIs and CDAD in high-risk antibiotics users by using a case-crossover design. METHODS: We conducted a case-crossover study using a nationwide population-based cohort in South Korea. Participants who developed CDAD from 1 January 2003 to 31 December 2013 and had prior prescription records of both PPIs and high-risk antibiotics were included. The hazard period was 49 days, and the three prior control periods had the same duration as the hazard period. The status of exposure to PPIs was assessed during the hazard and control periods in each patient and discordant pairs of exposure were used to estimate the matched odds ratio (OR). RESULTS: In total, 200 participants with CDAD who had histories of both PPIs and high-risk antibiotics use were included. A twofold increased risk for CDAD due to PPI use was observed (OR = 2.0; 95% confidence interval, 1.2-3.2). The time-invariant variables including age group, sex, and comorbidities were proven not to modify the association between PPIs and CDAD. CONCLUSIONS: Our study suggested that PPIs increase the risk of developing CDAD in high-risk antibiotics users. Thus, PPIs should be used cautiously in patients requiring high-risk antibiotics in the situation of medical treatment to prevent further incidence of CDAD.