Hospital Admissions For Acute Myocardial Infarction Research Articles

Effects of a coal to clean heating policy on acute myocardial infarction in Beijing: a difference-in-differences analysis

In 2015, the Chinese Government launched the coal to clean heating policy (CHP), designed to improve air quality and health in China. The CHP banned household coal burning and provided subsidies for clean electric or gas-powered heating for millions of peri-urban and rural households. We aimed to investigate whether the CHP affected the incidence of acute myocardial infarction in Beijing townships. In this quasi-experimental study, we obtained township data on acute myocardial infarction hospital admissions and deaths, exposure to the CHP (yes vs no), and a range of covariates for periods before (Jan 1, 2013, to Dec 31, 2014) and after the CHP began (Jan 1, 2016, to Dec 31, 2017; and Jan 1, 2018, to Dec 31, 2019). The policy was gradually rolled out across villages, and townships in our study were considered exposed to the policy in periods when more than 50% of their villages were assigned into the CHP. We estimated the effect of the CHP on township incidence of acute myocardial infarction for all adults (aged ≥35 years) and separately for sex and older adults (aged ≥65 years) using a difference-in-differences approach that accommodates the progressive roll-out of the policy. Of 307 townships in Beijing, we excluded 156 (51%) urban townships where most villages had central heating and were thus ineligible for the CHP. Of the 151 peri-urban and rural Beijing townships considered eligible for the CHP, 75 (50%) townships were exposed to the CHP by the end of 2017 and 92 (61%) by the end of 2019. We estimated an overall reduction of 6·6% (95% CI -12·3 to -0·8) in the incidence of acute myocardial infarction from before to after roll-out of the CHP in exposed townships relative to those not exposed to the policy, with some evidence of larger effects in women (-11·7% [-19·0 to -4·1%]), older adults (-10·7% [-17·4 to -3·6%]), and in townships exposed for longer (-3·5% [-9·5 to 2·8%] after <2 years and -9·7% [-18·3 to -0·5%] after 2-4 years). Our results provide among the first empirical evidence of possible cardiovascular benefits from a household clean energy policy, and support efforts to implement and assess such policies in China and globally. Wellcome Trust, the Canadian Institutes for Health Research, and the National Natural Science Foundation of China.

Changes in the care of acute cerebrovascular and cardiovascular conditions during the first year of the covid-19 pandemic in 746 hospitals in the USA: retrospective analysis

ObjectiveTo measure the impact of the covid-19 pandemic on admissions to hospital and interventions for acute ischemic stroke and acute myocardial infarction.DesignA retrospective analysis.Setting746 qualifying hospitals in the USA from...

COVID-19 pandemic on coronary artery and cerebrovascular diseases in Southern Spain: interrupted time series analysis.

Healthcare systems have been put under intense pressure by the COVID-19 pandemic, although some studies have shown a decline in hospital admissions for cardiovascular and cerebrovascular diseases during the first and second wave of the pandemic. In addition, studies analyzing gender and procedural differences are scarce. The present study aimed to determine the impact of the pandemic on hospital admissions for acute myocardial infarction (AMI) and cerebrovascular disease (CVD) in Andalusia (Spain) and analyzed differences by gender and by percutaneous coronary interventions performed. An interrupted time series analysis of AMI and CVD hospital admissions in Andalusia (Spain) was carried out to measure the impact of the COVID-19 outbreak. AMI and CVD cases admitted daily in public hospitals of Andalusia between January 2018 and December 2020 were included. During the pandemic, significant reductions in AMI [-19%; 95% confidence interval (CI): (-29%, -9%), p<0.001] and CVD [-17%; 95% CI: (-26%, -9%); p<0.01] in daily hospital admissions were observed. Differences were also produced according to the diagnosis (ST-Elevation Myocardial Infarction, Non-ST-Elevation Myocardial Infarction, other AMI and stroke), with a greater reduction in females for AMI and in males for CVD. Although there were more percutaneous coronary interventions during the pandemic, no significant reductions were observed. A decline in AMI and CVD daily hospital admissions during the first and second wave of COVID-19 pandemic was noted. Gender differences were observed, but no clear impact was observed in percutaneous interventions.

Hourly Valley Concentration of Air Pollutants Associated with Increased Acute Myocardial Infarction Hospital Admissions in Beijing, China

(1) Background: Acute myocardial infarction (AMI) imposes a great burden on global health. Few studies have demonstrated the effects of valley concentration of air pollutants on AMI hospital admissions. (2) Methods: Hospitalizations for AMI from 1 May 2014 to 31 December 2019 were analyzed. Generalized additive models (GAM) were used to quantify the exposure–response association between the hourly peak, mean, and valley concentration of six air pollutants and AMI hospital admissions. Stratification analyses were conducted to identify the susceptible population. (3) Results: Hourly peak, mean, and valley concentrations of PM2.5, PM10, SO2, NO2, and CO were significantly associated with AMI hospital admissions. Each 10-unit increase in the hourly valley concentration of them led to 0.50% (0.35–0.66%), 0.44 % (0.32–0.56%), 0.84% (0.47–1.22%), 1.86% (0.73–3.01%), and 44.6% (28.99–62.10%) excess risk in AMI hospital admissions, respectively. In addition, the effects of hourly valley concentration were larger than mean and peak concentrations. The effects in the female or older than 65 groups were larger than that in the male or younger than 65 groups. (4) Conclusions: PM2.5, PM10, SO2, NO2, and CO exposure contributed to increased AMI hospital admissions. Hourly valley concentration might be a more potent indicator of adverse cardiovascular events. Females and individuals older than 65 were more susceptible to ambient air pollutant exposure.

Abstract 330: Effect Of Covid-19 Mitigation On Resource Utilization And Rates Of Acute Myocardial Infarction In Areas Of Higher And Lower Socioeconomic Vulnerability

Background: Multiple reports demonstrate decreased emergency department (ED) utilization for cardiovascular emergencies during COVID-19. It is possible this decrease had downstream effects on the later severity of cardiovascular disease, especially in patients with higher social vulnerability. The purpose of this study was to determine the effect of early COVID-19 mitigation strategies on hospital resource utilization and acute myocardial infarction (AMI) admissions by social vulnerability. Methods: We retrospectively analyzed patients transported by emergency medical services (EMS) with a diagnosis of chest pain and/or AMI from a large urban Midwest EMS and single hospital system from Jan 1-Dec 31, 2020. Hospital office, telehealth, ED visits for chest pain, and hospital admissions for AMI were identified using the electronic health record. The 3 phases of COVID-19 mitigation were compared (pre-mitigation-Jan 1 st to Feb 28 th , mitigation-March 1 st to April 30 th , and post-mitigation-May 1 st -December 31 st ). The socioeconomic status theme of the Social Vulnerability Index (SVI) was determined. The primary outcome was rate of AMI per ED chest pain visit, which was compared between the highest and lowest SVI quartiles. Statistical comparisons were made using binary logistic regression and Chi-squared tests. Results: Overall, there was a similar increase in telehealth visits and a decrease in office visits during mitigation in both highest and lowest SVI quartiles. In the post-mitigation phase, patients with the highest social vulnerability had a 30% relative increase rate of AMI per ED chest pain visit (7.3% vs 5.5%, p=0.048) compared to patients with lower social vulnerability. This increase was not seen in the pre-mitigation (5.8% vs 6.1%) or mitigation (4.9% vs 5.4%, each p=ns) phases. Conclusions: After initial COVID-19 mitigation strategies were implemented patients with higher socioeconomic vulnerability presented to the ED with AMI at a higher rate than patients with a lower socioeconomic vulnerability, despite no differences in office, telehealth, or EMS transport. Understanding the complex effect of pandemic mitigation strategies on vulnerable populations can provide guidance for resource management in future crises.

Abstract 13292: Rural-Urban Differences in Mortality Rate of Myocardial Infarction and Heart Failure: A Systematic Review and Meta-Analysis

Introduction: Studies indicate that living in a rural area may be associated with worse health outcomes. However, it is unclear whether rurality is associated with mortality in patients with acute myocardial infarction (AMI) and heart failure (HF). This systematic review and meta-analysis aimed to evaluate rural-urban differences in mortality rate after AMI or HF. Methods: A systematic search was conducted for studies published till May 1, 2022 in PubMed, Embase and CENTRAL. Included studies compared mortality rates after hospital admission for AMI or HF in rural versus urban areas. Follow up ranged between 30 days and 3 years. Adjusted Odds ratios (aORs) were pooled with a random-effects model. Results: Six cohort studies were identified, which included 785,156 patients (128,990 in rural vs. 656,166 in urban) with AMI and 1,159,000 patients (192,749 in rural vs. 966,251 in urban) with HF. Compared with urban, patients admitted with AMI in rural areas had higher mortality rates (16% vs 14%, aOR 1.12, 95% Confidence Interval (CI) 1.05-1.20; p =0.0003, I 2 =75%). Compared with urban, patients admitted with HF in rural areas had higher mortality rates (21% vs 18%, aOR 1.19, 95% CI 1.03-1.38; p =0.02, I 2 =90%). (Figure) Conclusions: Among patients with AMI or HF, living in rural areas is associated with an increased risk of mortality. Clinical and policy efforts are needed in order to reduce disparities in rural health.

Association of sunshine duration with acute myocardial infarction hospital admissions in Beijing, China: A time-series analysis within-summer

BackgroundOver the years, various epidemiological studies found that acute myocardial infarction (AMI) often shows seasonal rhythm patterning, which is usually influenced by the variations of environmental factors, such as air pollution, ambient temperature, solar activity, relative humidity. However, there are few studies on the impact of sunlight-induced AMI especially in developing countries, and they had inconsistent results. This study aimed to examine within-summer variations in the temporal association between sun exposure and AMI. MethodsWe obtained hospitalization data for AMI of Beijing during 2013–2019. We used a distributed lag non-linear model (DLNM) combined with a quasi-Poisson regression model to estimate the non-linear lag effects of sunshine duration on AMI incidences. We evaluated the overall effect of AMI admissions with exposure to sunshine duration in the lag 0–21 days. ResultsA total of 45,301 AMI cases were enrolled in our study during summer (June–September). The minimum of the morbidity was during days with a sunshine duration of 3.9 h. We found significant and U-shaped associations between sunshine duration and AMI, and the overall estimated relative risk was 1.29 (95% CI: 1.02,1.62) and 1.69 (95% CI: 1.28,2.24) for short (1st percentile) and long (99th percentile) sunshine duration, respectively. The males and younger people (<65 years) were most susceptible to these effects. ConclusionOur results suggest that both short and long sunshine duration could increase the risk of AMI admissions, especially for males and younger people. We suggest that public health policymakers should fully consider the balance of the pros and cons of solar exposure, and provide appropriate public health recommendations accordingly to gain the greatest benefits from sunlight.

Impact of the COVID-19 Pandemic on Patient Delay and Clinical Outcomes for Patients With Acute Myocardial Infarction.

BackgroundIt has been known that the fear of contagion during the coronavirus disease 2019 (COVID-19) creates time delays with subsequent impact on mortality in patients with acute myocardial infarction (AMI). However, difference of time delay and clinical outcome in patients with ST-segment elevation myocardial infarction (STEMI) or non-STEMI between the COVID-19 pandemic and pre-pandemic era has not been fully investigated yet in Korea. The aim of this study was to investigate the impact of COVID-19 pandemic on time delays and clinical outcome in patients with STEMI or non-STEMI compared to the same period years prior.MethodsA total of 598 patients with STEMI (n = 195) or non-STEMI (n = 403) who underwent coronary angiography during the COVID-19 pandemic (February 1 to April 30, 2020) and pre-pandemic era (February 1 to April 30, 2017, 2018, and 2019) were analyzed in this study. Main outcomes were the incidence of time delay, cardiac arrest, and in-hospital death.ResultsThere was 13.5% reduction in the number of patients hospitalized with AMI during the pandemic compared to pre-pandemic era. In patients with STEMI, door to balloon time tended to be longer during the pandemic compared to pre-pandemic era (55.7 ± 12.6 minutes vs. 60.8 ± 13.0 minutes, P = 0.08). There were no significant differences in cardiac arrest (15.6% vs. 10.4%, P = 0.397) and in-hospital mortality (15.6% vs. 10.4%, P = 0.397) between pre-pandemic and the pandemic era. In patients with non-STEMI, symptom to door time was significantly longer (310.0 ± 346.2 minutes vs. 511.5 ± 635.7 minutes, P = 0.038) and the incidence of cardiac arrest (0.9% vs. 3.5%, P = 0.017) and in-hospital mortality (0.3% vs. 2.3%, P = 0.045) was significantly greater during the pandemic compared to pre-pandemic era. Among medications, angiotensin converting enzyme inhibitors/angiotensin type 2 receptor blockers (ACE-I/ARBs) were underused in STEMI (64.6% vs. 45.8%, P = 0.021) and non-STEMI (67.8% vs. 57.0%, P = 0.061) during the pandemic.ConclusionDuring the COVID-19 pandemic, there has been a considerable reduction in hospital admissions for AMI, time delay, and underuse of ACE-I/ARBs for the management of AMI, and this might be closely associated with the excess death in Korea.

Weather Impact on Acute Myocardial Infarction Hospital Admissions With a New Model for Prediction: A Nationwide Study.

Introduction: Cardiovascular disease is one of the leading causes of mortality worldwide. Acute myocardial infarction (AMI) is associated with weather change. The study aimed to investigate if weather change was among the risk factors of coronary artery disease to influence AMI occurrence in Taiwan and to generate a model to predict the probabilities of AMI in specific weather and clinical conditions.Method: This observational study utilized the National Health Insurance Research Database and daily weather reports from Taiwan Central Weather Bureau to evaluate the discharge records of patients diagnosed with AMI from various hospitals in Taiwan between January 1, 2008 and December 31, 2011. Generalized additive models (GAMs) were used to estimate the effective parameters on the trend of the AMI incidence rate with respect to the weather and health factors in the time-series data and to build a model for predicting AMI probabilities.Results: A total of 40,328 discharges were listed. The minimum temperature, maximum wind speed, and antiplatelet therapy were negatively related to the daily AMI incidence; however, a drop of 1° when the air temperature was below 15°C was associated with an increase of 1.6% of AMI incidence. By using the meaningful parameters including medical and weather factors, an estimated GAM was built. The model showed an adequate correlation in both internal and external validation.Conclusion: An increase in AMI occurrence in colder weather has been evidenced in the study, but the influence of wind speed remains uncertain. Our analysis demonstrated that the novel GAM model can predict daily onset rates of AMI in specific weather conditions.

Spatial Distribution of Hospitalizations for Ischemic Heart Diseases in the Central Region of Asturias, Spain.

Hospitalizations for ischemic heart disease have an uneven distribution throughout Spain, in which Asturias is the community with the highest rates of acute myocardial infarction (AMI) and angina pectoris (AP). Cardiovascular diseases are related to environmental, socioeconomic and previous medical conditions, which result in geographical differences in the incidence of hospital admissions and mortality. The goal of this study was to describe the spatial distribution of hospital admissions in the central area of Asturias and explore the existence of spatial patterns or clusters. Urgent hospital admissions for AMI and angina AP in the hospitals of the central area of Asturias were registered, geocoded and grouped by census tracts. Standardized admission ratio, smoothed relative risk, posterior risk probability and analysis of spatial clusters between relative risks throughout the study area were calculated and mapped. Geographical differences were found in the distribution of hospital admissions for AMI and AP across the area and between men and women. The cluster analysis indicated contiguous census tracts with high relative risk values in the northwest region of the study area and low relative risk in the east, particularly for men. The geographical analysis shows the existence of patterns and spatial clusters in the incidence of AMI and AP, for both men and women, in the central area of Asturias.

Case-ascertainment of acute myocardial infarction hospitalisations across two national data sources for an English cardio-oncology cohort

Abstract Background Cardio-oncology is an emerging field aimed at minimising cardiovascular morbidity and mortality in survivors of cancer. Though cardio-oncology patients make up a significant proportion of hospital admissions, they are typically excluded from clinical trials. Electronic health record-based research is a good alternative to understand the risk of cardiovascular disease in these patients. However, completeness and validity of cardiovascular outcome ascertainment may vary by data source. Purpose 1) Determine ascertainment of acute myocardial infarction (AMI) hospitalisations across two national data sources for English cancer patients, and 2) understand factors that affect ascertainment in this population. Methods English cancer patients were obtained from the National Cancer Registration and Analysis Service. AMI hospital admissions occurring during 2010–2017 were identified from two sources: the Myocardial Ischaemia National Audit Project (MINAP) registry and Hospital Episode Statistics (HES). Admissions were ascertainable from both MINAP and HES, or “matched”, if dated within 30 days. Results 112,502 hospital admissions for 95,509 patients were identified of which 57,265 (50.9%) admissions were captured in MINAP and HES, 26,104 (23.2%) in MINAP only, and 29,133 (25.9%) in HES only. Case-ascertainment percentages were similar across cancer site, stage and grade of disease. Cases ascertained from MINAP only were younger, had fewer comorbidities, and were more likely to have ST-elevated MI and better survival than those ascertained from HES only. The percentage of admissions that could be ascertained from both MINAP and HES has improved from over time. Conclusions MINAP and HES define different populations of cancer patients with AMI. Only half of AMI hospital admissions were captured in both MINAP and hospital records. Therefore, these results support the use of multiple linked data sources for observational cardio-oncological research into AMI. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): British Heart Foundation and Cancer Research UK

Case-ascertainment of acute myocardial infarction hospitalizations in cancer patients: a cohort study using English linked electronic health data.

AimsTo assess the recording and accuracy of acute myocardial infarction (AMI) hospital admissions between two electronic health record databases within an English cancer population over time and understand the factors that affect case-ascertainment.Methods and resultsWe identified 112 502 hospital admissions for AMI in England 2010–2017 from the Myocardial Ischaemia National Audit Project (MINAP) disease registry and hospital episode statistics (HES) for 95 509 patients with a previous cancer diagnosis up to 15 years prior to admission. Cancer diagnoses were identified from the National Cancer Registration Dataset (NCRD). We calculated the percentage of AMI admissions captured by each source and examined patient characteristics associated with source of ascertainment. Survival analysis assessed whether differences in survival between case-ascertainment sources could be explained by patient characteristics. A total of 57 265 (50.9%) AMI admissions in patients with a prior diagnosis of cancer were captured in both MINAP and HES. Patients captured in both sources were younger, more likely to have ST-segment elevation myocardial infarction and had better prognosis, with lower mortality rates up to 9 years after AMI admission compared with patients captured in only one source. The percentage of admissions captured in both data sources improved over time. Cancer characteristics (site, stage, and grade) had little effect on how AMI was captured.ConclusionMINAP and HES define different populations of patients with AMI. However, cancer characteristics do not substantially impact on case-ascertainment. These findings support a strategy of using multiple linked data sources for observational cardio-oncological research into AMI.

Impact of a comprehensive tobacco control policy package on acute myocardial infarction and stroke hospital admissions in Beijing, China: interrupted time series study

ObjectiveTo evaluate a comprehensive tobacco control policy package on hospital admissions for acute myocardial infarction (AMI) and stroke in a global city.DesignInterrupted time series study.SettingBeijing, China.Population31 707 AMI and 128...

In-hospital myocardial infarction and adherence to evidence-based drug therapies: a real-world evaluation

ObjectivesThis study aimed to measure adherence to chronic polytherapy following an acute myocardial infarction (AMI) and to find out associations between adherence and the setting of AMI onset (in vs...

Pattern of acute MI admissions in India during COVID-19 era: A Cardiological Society of India study - Rationale and design

BackgroundCOVID-19 pandemic has affected around 20million patients worldwide and 2.0 million cases from India. The lockdown was employed to delay the pandemic. However, it had an unintentional impact on acute cardiovascular care, especially acute myocardial infarction (AMI). Observational studies have shown a decrease in hospital admissions for AMI in several developed countries during the pandemic period. We aimed to evaluate the impact of COVID-19 on the AMI admissions patterns across India. MethodsIn this multicentric, retrospective, cross-sectional study, we included all AMI cases admitted to participating hospitals during the study period 15th March to 15th June 2020 and compared them using a historical control of all cases of AMI admitted during the corresponding period in the year 2019. Major objective of the study is to analyze the changes inthe number of hospital admissions for AMI in hospitals across India. In addition, we intend to evaluate the impact of COVID-19 on the weekly AMI admission rates, and other performance measures like rates of thrombolysis/primary percutaneous interventions (PCI), window period, door to balloon time, and door to needle time. Other objectives include evaluation of changes in the major complications and mortality rates of AMI and its predictors during COVID-19 pandemic. ConclusionsThis CSI-AMI study will provide scientific evidence about the impact of COVID-19 on AMI care in India. Based on this study, we may be able to suggest appropriate changes to the existing MI guidelines and to educate the public regarding emergency care for AMI during COVID-19 pandemic.

Acute Myocardial Infarction among Young Adult Men in a Region with Warm Climate: Clinical Characteristics and Seasonal Distribution

The aim of this cross sectional study was to investigate the influence of the seasons on acute myocardial infarction (AMI) among young adult among young adults aged <45 years compared to old adults aged ≥45 years. The seasonal distribution of AMI hospital admissions among young adult men in eastern Taiwan was assessed. Data were extracted from 1413 male AMI patients from January 1994 to December 2015, including onset date, the average temperature (Tave) on the date of AMI hospitalization (AMI-Tave), and conventional risk factors, notably smoking, diabetes, hypertension, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, and body mass index (BMI). The 1413 cases were divided into two groups: the young group (n = 138, <45 y/o) and the older group (n = 1275, ≥45 y/o). The differences between groups were examined. Logistic regression analyses were used to evaluate the associations between the seasons and the AMI hospitalization among the young group. The young group showed significantly higher percentage of smokers, BMI, total cholesterol levels, and triglycerides levels but lower percentage of diabetes and hypertension than the older group (p < 0.05). AMI hospitalization in winter was significantly greater compared to the other seasons among the young group (p < 0.05). Winter hospitalization was significantly associated with the young group relative to the older group (adjusted OR 1.750; 95% CI 1.151 to 2.259), while winter AMI-Tave in the young group was similar to that in the older group. Young adult men diagnosed with AMI are more likely than older adult men to be smokers, obese, and show an onset dependent on winter but not low-temperature in a region with a warm climate.

Education-related variation in coronary procedure rates and the contribution of private health care in Australia: a prospective cohort study

BackgroundContemporary Australian evidence on socioeconomic variation in secondary cardiovascular disease (CVD) care, a possible contributor to inequalities in cardiovascular disease outcomes, is lacking. This study examined the relationship between education, an individual-level indicator of socioeconomic position, and receipt of angiography and revascularisation procedures following incident hospitalisation for acute myocardial infarction (AMI) or angina, and the role of private care in this relationship.MethodsParticipants aged ≥45 from the New South Wales population-based 45 and Up Study with no history of prior ischaemic heart disease hospitalised for AMI or angina were followed for receipt of angiography or revascularisation within 30 days of hospital admission, ascertained through linked hospital records. Education attainment, measured on baseline survey, was categorised as low (no school certificate/qualifications), intermediate (school certificate/trade/apprenticeship/diploma) and high (university degree). Cox regression estimated the association (hazard ratios [HRs]) between education and coronary procedure receipt, adjusting for demographic and health-related factors, and testing for linear trend. Private health insurance was investigated as a mediating variable.ResultsAmong 4454 patients with AMI, 68.3% received angiography within 30 days of admission (crude rate: 25.8/person-year) and 48.8% received revascularisation (rate: 11.7/person-year); corresponding figures among 4348 angina patients were 59.7% (rate: 17.4/person-year) and 30.8% (rate: 5.3/person-year). Procedure rates decreased with decreasing levels of education. Comparing low to high education, angiography rates were 29% lower among AMI patients (adjusted HR = 0.71, 95% CI: 0.56–0.90) and 40% lower among angina patients (0.60, 0.47–0.76). Patterns were similar for revascularisation among those with angina (0.78, 0.61–0.99) but not AMI (0.93, 0.69–1.25). After adjustment for private health insurance status, the HRs were attenuated and there was little evidence of an association between education and angiography among those admitted for AMI.ConclusionsThere is a socioeconomic gradient in coronary procedures with the most disadvantaged patients being less likely to receive angiography following hospital admission for AMI or angina, and revascularisation procedures for angina. Unequal access to private health care contributes to these differences. The extent to which the remaining variation is clinically appropriate, or whether angiography is being underused among people with low socioeconomic position or overused among those with higher socioeconomic position, is unclear.

Inverse probability weighted distributed lag effects of short-term exposure to PM2.5 and ozone on CVD hospitalizations in New England Medicare participants - Exploring the causal effects

BackgroundAlthough many studies have established significant associations between short-term air pollution and the risk of getting cardiovascular diseases, there is a lack of evidence based on causal distributed lag modeling. MethodsInverse probability weighting (ipw) propensity score models along with conditional logistic outcome regression models based on a case-crossover study design were applied to get the causal unconstrained distributed (lag0-lag5) as well as cumulative lag effect of short-term exposure to PM2.5/Ozone on hospital admissions of acute myocardial infarction (AMI), congestive heart failure (CHF) and ischemic stroke (IS) among New England Medicare participants during 2000–2012. Effect modification by gender, race, secondary diagnosis of Chronic Obstructive Pulmonary Diseases (COPD) and Diabetes (DM) was explored. ResultsEach 10 μg/m3 increase in lag0-lag5 cumulative PM2.5 exposure was associated with an increase of 4.3% (95% confidence interval: 2.2%, 6.4%, percentage change) in AMI hospital admission rate, an increase of 3.9% (2.4%, 5.5%) in CHF rate and an increase of 2.6% (0.4%, 4.7%) in IS rate. A weakened lagging effect of PM2.5 from lag0 to lag5 could be observed. No cumulative short-term effect of ozone on CVD was found. People with secondary diagnosis of COPD, diabetes, female gender and black race are sensitive population. ConclusionsBased on our causal distributed lag modeling, we found that short-term exposure to an increased ambient PM2.5 level had the potential to induce higher risk of CVD hospitalization in a causal way. More attention should be paid to population of COPD, diabetes, female gender and black race.

P3618Underweight predicts greater risk of cardiac mortality post acute myocardial infarction

Abstract Background Increased body mass index (BMI) is a well-established risk factor for cardiovascular disease, however, patients with elevated BMI comparing to low BMI seem to have better survival, a phenomenon reported as “obesity paradox” which remains as a controversy. We investigated the effect of BMI, including underweight, normoweight, overweight and obese, on cardiac mortality post acute myocardial infarction (AMI). Methods This analysis included 3562 AMI patients with documented BMI. The baseline characteristics including clinical and laboratory parameters were collected at hospital admission for AMI. Patients were classified into 4 groups based on BMI values: underweight (BMI &lt;18.5), normoweight (BMI 18.5 to 24.9), overweight (BMI 25 to 29.9) and obese (BMI ≥30). Patients were followed up for a median of 1.9 years. The rate of cardiac death (primary endpoint) was compared among the 4 BMI groups. Cox proportional hazard models were used to adjust for potential confounders. Results Of 3562, 110 (3%) were underweight, 1579 (44%) were normoweight, 1493 (42%) were overweight, and 380 (11%) were obese. Compared to the normoweight group, subjects in overweight and obese groups were younger, more men, more hypertension, more likely to receive percutaneous coronary intervention (PCI), and had higher levels of glucose and lipids, but, lower level of N-terminal pro-brain natriuretic peptide (NTproBNP). Subjects in underweight group were older, more women, fewer diabetes, less likely to receive PCI, lower levels of glucose and lipids, but, higher level of NTproBNP and higher rates of left ventricular ejection fraction (LVEF)&lt;50%. Cardiac death over 1.9 years occurred significantly more in the underweight group (30.0%, 10.6%, 7.0% and 5.0% among the 4 groups from underweight to obese, p&lt;0.001 for trend, Figure 1). The Cox proportional hazard model revealed that underweight was an independent predictor of subsequent cardiac death (OR=2.58, 95% CI: 1.52–4.39, p&lt;0.001). Multivariate analysis identified that older age, higher levels of cardiac troponin I (cTnI) and LVEF&lt;50% were independently associated with increased risk of cardiac death. PCI significantly and independently protected AMI patients against cardiac death (OR=0.34, 95% CI: 0.23–0.49, p&lt;0.001). Conclusions Patients who were underweight were at greater risk of cardiac death post AMI. In addition, older age, higher levels of cTnI, LVEF&lt;50%, and not receiving PCI also independently predicted cardiac mortality post AMI. Acknowledgement/Funding Beijing Natural Science Foundation (No. 7194253);Scientific Research Common Program of Beijing Municipal Commission of Education (KM201910025017)

Association Between Inpatient Echocardiography Use and Outcomes in Adult Patients With Acute Myocardial Infarction

Guidelines recommend that patients with acute myocardial infarction (AMI) undergo echocardiography for assessment of cardiac structure and ejection fraction, but little is known about the association between echocardiography as used in routine clinical management of AMI and patient outcomes. To examine the association between risk-standardized hospital rates of transthoracic echocardiography and outcomes. This retrospective cohort study of data from 397 US hospitals that contributed to the Premier Healthcare Informatics inpatient database from January 1, 2014, to December 31, 2014, used International Classification of Diseases, Ninth Revision (ICD-9) codes to identify 98 999 hospital admissions for patients with AMI. Data were analyzed between October 2017 and January 2019. Rates of transthoracic echocardiography. Inpatient mortality, length of stay, total inpatient costs, and 3-month readmission rate. Among the 397 hospitals with more than 25 admissions for AMI in 2014, a total of 98 999 hospital admissions for AMI were identified for analysis (38.2% women; mean [SD] age, 66.5 [13.6] years), of which 69 652 (70.4%) had at least 1 transthoracic echocardiogram performed. The median (IQR) hospital risk-standardized rate of echocardiography was 72.5% (62.6%-79.1%). In models that adjusted for hospital and patient characteristics, no difference was found in inpatient mortality (odds ratio [OR], 1.02; 95% CI, 0.88-1.19) or 3-month readmission (OR, 1.01; 95% CI, 0.93-1.10) between the highest and lowest quartiles of echocardiography use (median risk-standardized echocardiography use rates of 83% vs 54%, respectively). However, hospitals with the highest rates of echocardiography had modestly longer mean lengths of stay (0.23 days; 95% CI, 0.04-0.41; P = .01) and higher mean costs ($3164; 95% CI, $1843-$4485; P < .001) per admission compared with hospitals in the lowest quartile of use. Multiple sensitivity analyses yielded similar results. In patients with AMI, hospitals in the quartile with the highest rates of echocardiography showed greater hospital costs and length of stay but few differences in clinical outcomes compared with hospitals in the quartile with the lowest rates of echocardiography. These findings suggest that more selective use of echocardiography might be used without adversely affecting clinical outcomes, particularly in hospitals with high rates of echocardiography use.