Acute Myocardial Infarction Hospitalization Rates Research Articles

Cardiovascular hospitalizations and mortality among adults aged 25-64 years in the USA.

Declines in cardiovascular mortality have stagnated in the USA since 2011. There is growing concern that these patterns reflect worsening cardiovascular health in younger adults. However, little is known about how the burden of acute cardiovascular hospitalizations and mortality has changed in this population. Changes in cardiovascular hospitalizations and mortality among adults aged 25-64 years were evaluated, overall and by community-level income. Using the National Inpatient Sample, age-standardized annual hospitalization and in-hospital mortality rates for acute myocardial infarction (AMI), heart failure, and ischaemic stroke were determined among adults aged 25-64 years. Quasi-Poisson and quasi-binominal regression models were fitted to compare outcomes between individuals residing in low- and higher-income communities. Between 2008 and 2019, age-standardized hospitalization rates for AMI increased among younger adults from 155.0 (95% confidence interval: 154.6, 155.4) per 100 000 to 160.7 (160.3, 161.1) per 100 000 (absolute change +5.7 [5.0, 6.3], P < .001). Heart failure hospitalizations also increased (165.3 [164.8, 165.7] to 225.3 [224.8, 225.8], absolute change +60.0 (59.3, 60.6), P < .001), as ischaemic stroke hospitalizations (76.3 [76.1, 76.7] to 108.1 [107.8, 108.5], absolute change +31.7 (31.2, 32.2), P < .001). Across all conditions, hospitalizations rates were significantly higher among younger adults residing in low-income compared with higher-income communities, and disparities did not narrow between groups. In-hospital mortality decreased for all conditions over the study period. There was an alarming increase in cardiovascular hospitalizations among younger adults in the USA from 2008 to 2019, and disparities between those residing in low- and higher-income communities did not narrow.

Abstract 12921: National Trends and Sex Differences in Adults &lt; 35 Years Old With Acute Myocardial Infarction in the United States From 2010 - 2018

Introduction: Few studies have examined acute myocardial infarction (AMI) trends among adults &lt; 35 years old. We analyzed hospitalization and mortality trends, risk factors, and sex differences among patients &lt; 35 years old with AMI. Methods: We queried the National Readmissions Database (NRD) for all hospitalizations from 2010 to 2018 aged 20-34 with a principal diagnosis of AMI. We assessed the annual trend in AMI hospitalization rates and in-hospital mortality using linear regression, stratifying by sex. We analyzed procedures and risk factors both overall and by sex, and performed bivariate analyses using chi-square to compare sex differences. All frequencies were weighted to reflect national estimates provided by the NRD. Results: A total of 40,209 AMI hospitalizations in individuals &lt; 35 years old were identified from 2010 to 2018. Hospitalization rates were higher in men as compared with women (9.6/100,000 vs. 4.0/100,000, p &lt; 0.05) and remained stable for men while there was a trend towards increasing hospitalization rates for women (Figure, p = 0.06). Women were more likely to be hypertensive, diabetic, and obese, while men were more likely to have hyperlipidemia and a history of tobacco or cocaine use (all p &lt; 0.01). The rate of obesity increased over time for both men and women while rates of hypertension and diabetes increased only for women (all p &lt; 0.05). As compared with men, women were less likely to get PCI (47.8% vs. 54.9%, p &lt; 0.01) but in-hospital mortality rates were similar (2.22% vs. 1.60%, p = 0.29). Conclusions: Among those &lt; 35 years old with AMI, women were more likely to be hypertensive, diabetic, and obese, with increasing prevalence, while men were more likely to have hyperlipidemia and a history of tobacco or cocaine use. Hospitalization rates for AMI were higher in men and there was a significantly higher use of PCI in men compared to women although in-hospital mortality rates were similar.

Assessment of the Impact of the Implementation of a Pre-Hospital Ambulance System on Acute Myocardial Infarction Mortality in a Developing Country.

The effective management of patients with acute myocardial infarction (AMI) is time-dependent. To assess the impacts of the implementation of prehospital care on admission rates and mortality associated with AMI. Retrospective, ecological study, which assessed data from the Brazilian Universal Health System, from all 853 municipalities of Minas Gerais, from 2008 to 2016. Excessive skewness of general and in-hospital mortality rates was smoothed using the empirical Bayes method. This study assessed the relationship between Mobile Emergency Care Service (SAMU) in each municipality and the following 3 outcomes: mortality rate due to AMI, AMI in-hospital mortality, and AMI hospitalization rate, using the Poisson hierarchical model. Rates were corrected by age structure and detrended by seasonality and temporal influences. A confidence interval of 95% was adopted. AMI mortality rates decreased throughout the study, on average 2% per year, with seasonal variation. AMI in-hospital mortality also showed a decreasing trend, from 13.81% in 2008 to 11.43% in 2016. SAMU implementation was associated with decreased AMI mortality (odds ratio [OR] = 0.967, 95% confidence interval [CI] 0.936 to 0.998) and AMI in-hospital mortality (OR = 0.914, 95% CI 0.845 to 0.986), with no relation with hospitalizations (OR = 1.003, 95% CI 0.927 to 1.083). SAMU implementation was associated with a modest but significant decrease in AMI in-hospital mortality. This finding reinforces the key role of prehospital care in AMI care and the need for investments on this service to improve clinical outcomes in low- and middle-income countries.

653 The impact of the COVID-19 pandemic on hospitalizations for acute myocardial infarction: the experience of the Clinical Cardiology Unit, University Hospital of Cagliari

AimsDuring the COVID-19 pandemic, hospitalization rates for acute myocardial infarction (AMI) decreased worldwide. The aim of the study is to evaluate the impact of the COVID-19 pandemic on the admission rate for AMI to our academic hospital, to monitor the trend during the reopening phase and to evaluate if whether changes in air pollution may have influenced hospitalization rates for AMI in Sardinia and Northern Italy.Methods and resultsWe compared the admission rate for AMI in our department and, by analysing the density of nitrogen dioxide (1/cm2), the state of air pollution in Sardinia and Northern Italy in different periods: the national lockdown (9 March–3 May 2020), the 8 weeks before the start of the lockdown, the 8 weeks after the end of the lockdown and the corresponding time period in 2019 (from 9 March to 3 May 2019). A marked decline in AMI admissions was observed during the lockdown period in comparison with the 8 weeks before the start of the lockdown (−47%, 95% CI: 37.5–56.7, P < 0.0001) and the corresponding period in 2019 (−52.8%, 95% CI: 43–65, P < 0.0001). There was a significant reduction in hospitalizations for NSTEMI during the lockdown period in comparison with the 8 weeks before the start of lockdown (−71.8%, 95% CI: 62.3–79.6, P < 0.0001) and the corresponding time period in 2019 (−70.5%, 95% CI: 60.9–78.5, P < 0.0001). Similar trends were seen in the group of STEMI patients, but the fall in admissions was less than that of NSTEMI patients. During the lockdown period, the hospitalizations for STEMI fell by 31.5% (95% CI: 23.2–41.4, P = 0.19) and 49% (95% CI: 39.4–58.6, 47 vs. 24 admissions, P = 0.009) in comparison to the 8 weeks before the start of lockdown and the corresponding period in 2019, respectively. We observed a rise in AMI admissions during the 8 weeks after the lockdown (+47%, 95% CI: 37.5–56.7, P < 0.0001), for both NSTEMI (+71.2%, 95% CI: 61.7–79.1, P < 0.0001) and STEMI (+33.4%, 95% CI: 24.9–43.1, P = 0.15). In Sardinia the relative change in nitrogen dioxide density during the time of lockdown was negligible with little or no impact on the environment (−19%, 95% CI: 12.5–27.7, P = 0.65), if we consider it occurred within a range of very low values of nitrogen dioxide (11.5 ± 3 e 14.1 ± 5 μmol/m2). In contrast, in Northern Italy during the lockdown there was a marked decrease in NO2 concentration in comparison with the 8 weeks before the start of lockdown (−53%, 95% CI: 43–62.4, 25.1 ± 16.2 e 54.2 ± 43.5 μmol/m2, P < 0.0001).ConclusionsSince air pollution did not change substantially in our region, the environment factor cannot explain the decline in the number of admissions for AMI we recorded during the lockdown. Fear of contagion is the most plausible reason for the drop of hospitalizations for AMI during the lockdown period.

Acute myocardial infarction associated with unconventional natural gas development: A natural experiment

BackgroundWhereas it is plausible that unconventional natural gas development (UNGD) may adversely affect cardiovascular health, little is currently known. We investigate whether UNGD is associated with acute myocardial infarction (AMI). MethodsIn this observational study leveraging the natural experiment generated by New York's ban on hydraulic fracturing, we analyzed the relationship between age- and sex-specific county-level AMI hospitalization and mortality rates and three UNGD drilling measures. This longitudinal panel analysis compares Pennsylvania and New York counties on the Marcellus Shale observed over 2005–2014 (N = 2840 county-year-quarters). ResultsA hundred cumulative wells is associated with 0.26 more hospitalizations per 10,000 males 45-54y.o. (95% CI 0.07,0.46), 0.40 more hospitalizations per 10,000 males 65-74y.o. (95% CI 0.09,0.71), 0.47 more hospitalizations per 10,000 females 65-74y.o. (95% CI 0.18,0.77) and 1.11 more hospitalizations per 10,000 females 75y.o.+ (95% CI 0.39,1.82), translating into 1.4–2.8% increases. One additional well per square mile is associated with 2.63 more hospitalizations per 10,000 males 45-54y.o. (95% CI 0.67,4.59) and 9.7 hospitalizations per 10,000 females 75y.o.+ (95% CI 1.92,17.42), 25.8% and 24.2% increases, respectively. As for mortality rates, a hundred cumulative wells is associated with an increase of 0.09 deaths per 10,000 males 45-54y.o. (95% CI 0.02,0.16), a 5.3% increase. ConclusionsCumulative UNGD is associated with increased AMI hospitalization rates among middle-aged men, older men and older women as well as with increased AMI mortality among middle-aged men. Our findings lend support for increased awareness about cardiovascular risks of UNGD and scaled-up AMI prevention as well as suggest that bans on hydraulic fracturing can be protective for public health.

Impact of Qingdao's smoke-free legislation on hospitalizations and mortality from acute myocardial infarction and stroke: an interrupted time-series analysis.

More than 20 cities in China have enacted local smoke-free laws that prohibit smoking in public places. Only two of these cities have examined the health impact of the law. Enacted in 2013, Qingdao's smoke free-law was stricter than most other municipal smoke-free laws because it did not allow designated smoking rooms. This study aimed to estimate the impact of Qingdao's smoke-free legislation on acute myocardial infarction (AMI) and stroke. We used an interrupted time-series design adjusting for underlying secular trends, seasonal patterns and meteorological factors to estimate the impact of the smoke-free law on AMI and stroke events among permanent residents aged 35years or older in Qingdao, China. The study period was from 1January 2010 to 31December 2015, with a post-ban follow-up of approximately 2.5years. Outcome measures were weekly numbers of hospitalizations and deaths due to AMI/stroke. A total of 10 371 and 56 101 patients were hospitalized, with a principal discharge diagnosis of AMI and stroke, respectively; 32 196 AMI and 49 711 stroke deaths occurred during the study period. Following the smoke-free legislation, an incremental 20% [95% confidence interval (CI) =14-26%] and 8% (95% CI=3-13%) decrease per year was observed in AMI and stroke hospitalization rates, respectively. Neither the immediate nor gradual change in AMI nor stroke mortality rates associated with the law was statistically significant (P>0.05). Post-hoc subgroup analyses indicated that statistically significant reductions in AMI hospitalizations were evident among both the 35-64 (18% per year, 95% CI=12-27%) and 65-84 (20% per year, 95% CI=12-27%) age groups. Statistically significant reductions in stroke hospitalization were only in the older subgroup (13% per year, 95% CI=8-18%). The 2013 smoke-free legislation in Qingdao, China was associated with reduction in hospitalization from acute myocardial infarction and stroke among permanent residents aged 35years or older. There was no statistically significant reduction in mortality from acute myocardial infarctions or stroke.

Abstract P155: Acute Stress From Elections and Hospitalization for Acute Myocardial Infarction

Background: A growing body of evidence suggests that stressors are associated with heightened cardiovascular risk within hours after the triggering event, and stress from election campaigns is associated with a heightened risk of pre-term birth. Hypothesis: Potential stress from the 2016 presidential election was associated with an increased hospitalization rate for acute myocardial infarction (AMI) in the following week. Methods: Among active members 18 years of age and older in Kaiser Permanente Southern California, AMI was defined as an inpatient hospitalization with a primary discharge diagnosis of ICD-10-CM codes I21.x or I22.x. In an ecological analysis, we calculated relative risks (RR) and 95% confidence intervals (CI) comparing rates of AMI per 100,000 person-years (PY) within one week following the date of the 2016 presidential election (risk window) to rates in the prior two weeks (control window) overall and within subgroups by age, sex, and race/ethnicity. We repeated the above analysis comparing rates of AMI within one week of the 2016 election date to rates in the prior week. Results: Compared to the rates of MI in the two weeks before the 2016 election (171.6 per 100,000 PY), the rate of AMI hospitalization in the week following election day (242.2 per 100,000 PY) was 1.41 times higher (95% CI 1.14, 1.75). (Table) Heightened AMI risk after the 2016 election was also observed among adults 55-74 years of age (RR 1.47, 95% CI 1.10, 1.98), men (RR 1.54, 95% CI 1.17, 2.02), and white individuals (RR 1.52, 95% CI 1.12, 2.06). However, there was no evidence of heterogeneity across age, sex, or race/ethnicity groups (p-values 0.98, 0.30, and 0.65, respectively). Using a one-week control window, similar results were observed. Conclusion: Increased AMI rates among subsets of the population coincident with the 2016 election is consistent with published data suggesting that acute sociopolitical stress may have adverse health effects.

One In Five Fewer Heart Attacks: Impact, Savings, And Sustainability In San Diego County Collaborative

Before 2011 rates of hospitalization for heart attacks were about the same in San Diego County as they were in the rest of California. In 2011 a multistakeholder population health collaborative consisting of partners at the federal, state, and local levels launched Be There San Diego. The collaborative's goal was to reduce cardiovascular events through the spread of best practices aimed at improving control of hypertension, lipid levels, and blood sugar and through patient and medical community activation. Using hospital discharge data for the period 2007-16, we compared acute myocardial infarction (AMI) hospitalization rates in San Diego County and the rest of the state before and after the demonstration project started. AMI hospitalization rates decreased by 22percent in San Diego County versus 8percent in the rest of the state, with an estimated 3,826 AMI hospitalizations avoided and $86million in savings in San Diego. Results show that a science-based health collaborative can improve outcomes while lowering costs, and efforts are under way to ensure the collaborative's sustainability.

Quality of Care in the United States Territories, 1999-2012.

Millions of Americans live in the US territories, but health outcomes and payments among Medicare beneficiaries in these territories are not well characterized. Among Fee-for-Service Medicare beneficiaries aged 65 years and older hospitalized between 1999 and 2012 for acute myocardial infarction (AMI), heart failure (HF), and pneumonia, we compared hospitalization rates, patient outcomes, and inpatient payments in the territories and states. Over 14 years, there were 4,350,813 unique beneficiaries in the territories and 402,902,615 in the states. Hospitalization rates for AMI, HF, and pneumonia declined overall and did not differ significantly. However, 30-day mortality rates were higher in the territories for all 3 conditions: in the most recent time period (2008-2012), the adjusted odds of 30-day mortality were 1.34 [95% confidence interval (CI), 1.21-1.48], 1.24 (95% CI, 1.12-1.37), and 1.85 (95% CI, 1.71-2.00) for AMI, HF, and pneumonia, respectively; adjusted odds of 1-year mortality were also higher. In the most recent study period, inflation-adjusted Medicare in-patient payments, in 2012 dollars, were lower in the territories than the states, at $9234 less (61% lower than states), $4479 less (50% lower), and $4403 less (39% lower) for AMI, HF, and pneumonia hospitalizations, respectively (P<0.001 for all). Among Medicare Fee-for-Service beneficiaries, in 2008-2012 mortality rates were higher, or not significantly different, and hospital reimbursements were lower for patients hospitalized with AMI, HF, and pneumonia in the territories. Improvement of health care and policies in the territories is critical to ensure health equity for all Americans.

Association between Air Temperature and Acute Myocardial Infarction Hospitalizations in Tehran, Iran: A Time-Stratified Case-Crossover.

Background: Although the effect of temperature on the incidence of acute myocardial infarction (AMI) has been extensively documented, no study has previously investigated the association between temperature and AMI in the Middle Eastern countries.Objective: To examine the association between daily mean temperature and AMI admission rates in Tehran, Iran. Methods:Data on daily number of admissions of patients with AMI to Tehran hospitals between March 21, 2013 and March 19, 2016, were retrieved from the Iranian Myocardial Infarction Registry (IMIR). Over the same period, data on daily mean temperature and relative humidity were measured at Mehrabad International Airport weather station of the Islamic Republic of Iran Meteorological Organization. Time-stratified case-crossover design was employed to investigate the short-term association between the daily mean temperature and the number of daily admissions of patients with AMI, after adjusting for public holidays, relative humidity, and air pollution. Results:An interquartile range (IQR) increase in daily mean temperature was associated with 15.1% (95% CI 1.3 to 30.8%) and 13% (95% CI 1.9% to 25.4%) increase in the risk of AMI hospitalizations during the entire year, and in the warm months of the year, respectively. There were no significant associations between IQR increase in the two-day cumulative average up to the six-day cumulative average of the daily mean temperature and AMI during the entire year, and warm or cold months of the year. Conclusion:An increase in temperature would increase the rate of AMI hospitalization.

Abstract P341: Community Environment Associated with Cardiovascular Disease Hospitalization Rates in Denver, Colorado

Introduction: Hospitalization rates for acute myocardial infarction (AMI), coronary heart disease (CHD), and stroke have decreased over time, although trends are debatable for heart failure (HF). These trends are unequally distributed. There is a growing literature documenting the relationship between social and economic characteristics of people’s communities and cardiovascular disease (CVD). Based on a social ecological model of health through the life course, we descriptively examined associations between CVD hospitalization rates and patient characteristics and census tract (CT)-level community environment. Hypothesis: CVD hospitalization rates will be higher in community environments with higher percentages of individuals living below the federal poverty level, racial/ethnic minority groups, and non-residential (i.e., commercial/office, industrial, open space, public/civic, vacant, and miscellaneous space) vs. residential land use. Methods: Colorado Hospital Association (2009-2013) data were used to measure ICD-9 coded hospitalization rates (per 1,000) for Denver, Colorado residents ≥20 years. Data were merged with American Community Survey (2009-2013) and Denver County land use (2010) data. Using chi-square analysis, we examined associations between age-adjusted CVD hospitalization rates (N=15,521) and CT-level community environment (in quartiles) (N=144). Results: Denver’s annual CVD hospitalization rate was 6.6. Patient-level AMI (1.7), CHD (2.8), and HF (2.2) rates were higher among men. Women had higher stroke-related rates (2.4). Across CVD types, rates for those ≥65 years (6.5-13.5) were higher than middle-aged groups (2.1-3.4). Average annual age-adjusted AMI hospitalization rates were higher in CTs with the highest quartile of Hispanic Americans (2.0), Native Americans (1.9), and individuals below poverty (1.9). CHD rates were higher in CTs with higher percentages of Hispanic Americans (3.1), individuals below poverty (3.1), and Native Americans (3.1). HF rates were higher in CTs with higher percentages of industrial/office land use (3.5), individuals below poverty (3.3), and Hispanic Americans (3.2). Stroke rates were higher in CTs with higher percentages of Native Americans (3.0), industrial/office land use (3.0), and African Americans (3.0). The largest disparities for rate ratios comparing the highest to the lowest quartiles for each exposure by CVD outcome were the percentage of individuals below poverty (AMI 2.2; CHD 2.1; HF 2.4; Stroke 1.7), non-Hispanic Whites (AMI 0.7; CHD 0.7; HF 0.7; Stroke 0.7), Hispanic Americans (AMI 1.5; CHD 1.5; HF 1.5), and Native Americans (Stroke 1.30). Conclusions: In conclusion, associations exist between community environment and CVD hospitalization rates, suggesting opportunities for health policy development in Denver’s city government, council districts, and neighborhoods .

Ethnic inequalities in acute myocardial infarction hospitalization rates among young and middle-aged adults in Northern Italy: high risk for South Asians.

The knowledge of ethnic-specific health needs is now essential to design effective health services and population-based prevention strategies. However, data on migrant populations living in Southern Europe are limited. The study is designed to investigate ethnic inequalities in hospitalization for acute myocardial infarction (AMI) in the Veneto region (Italy). Hospital admissions for AMI in Veneto for the whole resident population aged 20-59years during 2008-2013 were studied. Age and gender-specific AMI hospitalization rates for immigrant groups (classified by country of origin according to the United Nations geoscheme) and Italians were calculated. The indirect standardization method was used to estimate standardized hospitalization ratios (SHR) for each immigrant group, with rates of Italian residents as a reference. Overall, 8200 AMI events were retrieved, 648 among immigrants. The highest risk of AMI is seen in South Asians males (SHR 4.2, 95% CI 3.6-4.9) and females (SHR 2.5, 95% CI 1.4-4.5). AMI rates in South Asian males sharply increase in the 30-39years age class. Other immigrant subgroups (Eastern Europe, North Africa, Sub-Saharan Africa, other Asian countries, Central-South America, high-income countries) displayed age- and gender-adjusted hospitalization rates similar to the native population. Present findings stress the urgent need for implementation of ethnic-specific health policies in Italy. The awareness about the high cardiovascular risk in subjects from South Asia must be increased among general practitioners and immigrant communities.

Geographic Variation in Trends and Disparities in Acute Myocardial Infarction Hospitalization and Mortality by Income Levels, 1999-2013.

During the past decade, the incidence and mortality associated with acute myocardial infarction (AMI) in the United States have decreased substantially. However, it is unknown whether these improvements were consistent across communities of different economic status and geographic regions since efforts to improve cardiovascular disease prevention and management may have had variable impact. To determine whether trends in US county-level, risk-standardized AMI hospitalization and mortality rates varied by county-based median income level. In this observational study, county-level risk-standardized (age, sex, and race) hospitalization and 1-year mortality rates for AMI from January 1, 1999, to December 31, 2013, were measured for Medicare beneficiaries 65 years or older. Data analysis was performed from June 2 through December 1, 2015. Counties were stratified by median income percentile using 1999 US Census Bureau data adjusted for inflation: low- (<25th), average- (25th-75th), or high- (>75th) income groups. The effect of income on the slope of AMI hospitalizations and mortality, measured as differences in the rate of change in AMI hospitalizations and mortality by county income and by the 4 US geographic regions, and a possible lag effect among low-income counties. In the 15-year study period, AMI risk-standardized hospitalization and mortality rates decreased significantly for all 3 county income groups. Mean hospitalization rates were significantly higher among low-income counties compared with high-income counties in 1999 (1353 vs 1123 per 100 000 person-years, respectively) and in 2013 (853 vs 648 per 100 000 person-years, respectively). One-year mortality rates after hospitalization for AMI were similar across county income groups, decreasing from 1999 (31.5%, 31.4%, and 31.1%, for high-, average-, and low-income counties, respectively) to 2013 (26.2%, 26.1%, and 25.4%, respectively). Income was associated with county-level, risk-standardized AMI hospitalization rates but not mortality rates. Increasing 1 interquartile range of median county consumer price index-adjusted income ($12 000) was associated with a decline in 46 and 37 hospitalizations per 100 000 person-years for 1999 and 2013, respectively; interaction between income and time was 0.56. The rate of decline in AMI hospitalizations was similar for all county income groups; however, low-income counties lagged behind high-income counties by 4.3 (95% CI, 3.1-5.9) years. There were no significant differences in trends across geographic regions. Hospitalization and mortality rates of AMI declined among counties of all income levels, although hospitalization rates among low-income counties lag behind those of the higher income groups. These findings lend support for a more targeted, community-based approach to AMI prevention.

Abstract 5: Trends in Hospitalization Rates and Mortality for Acute Myocardial Infarction by Community Income Level: 1999-2013

Background: Over the last decade, acute myocardial infarction (AMI) incidence and mortality have decreased substantially. Yet it is unknown whether these improvements were consistent across communities of different economic status and geographic regions, for which efforts to improve cardiovascular disease prevention and management may have had variable impact. Objective: To compare trends in risk-standardized AMI hospitalization and 1-year mortality rates from 1999 to 2013 between counties of low, average, and high median income, and to test the effects of income over time and across the 4 U.S. geographic regions. Methods: We performed an observational analysis comparing trends in county-level risk-standardized (age, sex, race) AMI hospitalization and 1-year mortality rates from 1999 to 2013 among Medicare beneficiaries ≥65 years, testing for effects of county-income. Counties were stratified by median income percentile using 1999 U.S. Census Bureau data, adjusted for inflation, as: low (&lt;25th), average (25-75th) or high (&gt;75th) income groups. Using a mixed effects model, we compared trends in AMI hospitalization and mortality rates, stratified by county income. We tested for a lagged effect among low-income counties and compared trends between the 4 U.S. regions. Results: Income was significantly associated with AMI hospitalization, but not 1-year mortality rates. In the 15-year period, AMI risk-standardized hospitalization and mortality rates declined across all three county income groups, though absolute hospitalization rates differed significantly by county income groups (Figure). Low-income county hospitalization rates consistently lagged behind high-income county rates by 4.3 (95%CI: 3.1-5.9) years. There was no difference in rate of decline by geographic region. Conclusion: In this national study of AMI trends from 1999 to 2013, Medicare beneficiaries residing in counties of all income levels achieved substantial declines in AMI hospitalization and mortality. These broad-scale declines may reflect the success of focused AMI prevention efforts or other more secular trends. Nonetheless, disparities persist with low-income counties lagging behind high-income counties - a focus for future national efforts.

Recent Trends in Hospitalization for Acute Myocardial Infarction in Beijing

Comparable data on trends of hospitalization rates for ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) remain unavailable in representative Asian populations.To examine the temporal trends of hospitalization for acute myocardial infarction (AMI) and its subtypes in Beijing.Patients hospitalized for AMI in Beijing from January 1, 2007 to December 31, 2012 were identified from the validated Hospital Discharge Information System. Trends in hospitalization rates, in-hospital mortality, length of stay (LOS), and hospitalization costs were analyzed by regression models for total AMI and for STEMI and NSTEMI separately. In total, 77,943 patients were admitted for AMI in Beijing during the 6 years, among whom 67.5% were males and 62.4% had STEMI. During the period, the rate of AMI hospitalization per 100,000 population increased by 31.2% (from 55.8 to 73.3 per 100,000 population) after age standardization, with a slight decrease in STEMI but a 3-fold increase in NSTEMI. The ratio of STEMI to NSTEMI decreased dramatically from 6.5:1.0 to 1.3:1.0. The age-standardized in-hospital mortality decreased from 11.2% to 8.6%, with a significant decreasing trend evident for STEMI in males and females (P < 0.001) and for NSTEMI in males (P = 0.02). The rate of percutaneous coronary intervention increased from 28.7% to 55.6% among STEMI patients. The total cost for AMI hospitalization increased by 56.8% after adjusting for inflation, although the LOS decreased by 1 day.The hospitalization burden for AMI has been increasing in Beijing with a transition from STEMI to NSTEMI. Diverse temporal trends in AMI subtypes from the unselected "real-world" data in Beijing may help to guide the management of AMI in China and other developing countries.

Trends in acute myocardial infarction hospitalizations: Are we seeing the whole picture?

Payers and policy makers rely on studies of trends in acute myocardial infarction (AMI) hospitalizations and spending that count only hospitalizations where the AMI is the principal discharge diagnosis. Hospitalizations with AMI coded as a secondary diagnosis are ignored. The effects of excluding these hospitalizations on estimates of trends are unknown. Observational study of all AMI hospitalizations in Fee-for-Service Medicare beneficiaries 65 years and older, from 2002 through 2011. We studied 3,663,137 hospitalizations with any AMI discharge diagnosis over 288,873,509 beneficiary-years. Of these, 66% had AMI coded as principal (versus secondary). From 2002 to 2011, AMI hospitalization rates declined 24.5% (from 1,485 per 100,000 beneficiary-years in 2002 to 1,122 in 2011). Meanwhile, the proportion of these hospitalizations with a secondary AMI diagnosis increased from 28% to 40%; by 2011 these secondary AMI hospitalizations accounted for 43% of all expenditures for hospitalizations with AMI, or $2.8 billion. Major changes in comorbidities, principal diagnoses and mean costs for hospitalizations with a non-principal AMI diagnosis occurred in the 2006-2008 timeframe. Current estimates of the burden of AMI ignore an increasingly large proportion of overall AMI hospitalizations and spending. Changes in the characteristics of hospitalizations that coincided with major payment and policy changes suggest that non-clinical factors affect AMI coding. Failing to consider all AMIs could inflate estimates of population health improvements, overestimate the value of AMI prevention and treatment and underestimate current and future AMI burden and expenditures.

Trends in and disparities for acute myocardial infarction: an analysis of Medicare claims data from 1992 to 2010.

BackgroundIt is unknown whether previously reported disparities for acute myocardial infarction (AMI) by race and sex have declined over time.MethodsWe used Medicare Part A administrative data files for 1992 to 2010 to evaluate changes in per-capita hospitalization rates for AMI, rates of revascularization (percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG)), and 30-day mortality for four distinct patient subcohorts: black women; black men; white women; and white men, adjusted for age, comorbidities and year using logistic regression.ResultsThe study sample consisted of 4,045,267 AMI admissions between the years 1992 and 2010 (166,660 black women; 116,201 black men; 1,870,816 white women; 1,891,590 white men). AMI hospitalization rates differed significantly in 1992 to 1993 among black women (61.6 hospitalizations per 10,000 Medicare enrollees), black men (73.2 hospitalizations), white women (72.0 hospitalizations) and white men (113.2 hospitalizations) (P <0.0001). By 2009 to 2010 AMI hospitalization rates had declined substantially in all cohorts but disparities remained with significantly lower hospitalization rates among women and blacks compared to men and whites, respectively (P <0.0001). In multivariable-adjusted analyses, despite narrowing of the differences between cohorts over time, disparities in AMI hospitalization rates by race and sex remained statistically significant in 2009 to 2010 (P <0.001). In 1992 to 1993 and 2009 to 2010, rates of PCI within 30-days of AMI differed significantly among black women (8.6% in 1992 to 1993; 24.2% in 2009 to 2010), black men (10.4% and 32.6%), white women (12.8% and 30.5%), and white men (16.1% and 40.7%) (P <0.0001). In multivariable-adjusted analyses, racial disparities in procedure utilization appeared somewhat larger and sex-based disparities remained significant. Unadjusted 30-day mortality after AMI in 1992 to 1993 for black women, black men, white women and white men was 20.4%, 17.9%, 23.1% and 19.5%, respectively (P <0.0001); in 2009 to 2010 mortality was 17.1%, 15.3%, 18.2% and 16.2%, respectively (P <0.0001). In adjusted analyses, racial differences in mortality declined over time but differences by sex (higher mortality for women) persisted.ConclusionsDisparities in AMI have declined modestly, but remain a problem, particularly with respect to patient sex.Electronic supplementary materialThe online version of this article (doi:10.1186/s12916-014-0190-6) contains supplementary material, which is available to authorized users.

Abstract 123: A Comparison of In-Hospital Acute Myocardial Infarction Management Between Portugal and the United States: 2000 - 2010

Objectives: Because inter- and intra-country variations in the adoption of medical technologies exist, international comparative studies provide an opportunity to infer technology effectiveness. Few studies have characterized recent trends in acute myocardial infarction (AMI) management between countries. Methods: Repeated cross-sectional observational cohorts of hospitalized adults aged ≥20 years discharged between January 2000 and December 2010. We identified new AMI hospitalizations using a US national 20% inpatient sample and a 100% inpatient sample in all Portuguese public sector hospitals. Age, sex, comorbidities, and median length of stay (interquartile range [IQR]) were determined. Annual age-sex adjusted hospitalization rates (HR) for AMI, in-hospital procedures, and in-hospital mortality were directly standardized to the 2010 US population. Intra-country (2010 relative to 2000) and inter-country in 2010 (Portugal [PT] relative to US) rate ratios [RR] were estimated. Findings: We identified 1476808 AMI US hospitalizations and 126314 Portugal hospitalizations between 2000 and 2010. Portuguese patients were more male, younger, and had fewer comorbidities compared to US patients (Table). The age-sex adjusted AMI HR decreased from 21 per 1000 person-years to 15 in the US (RR=0.70; 95% CI = [0.70, 0.71]) but increased in PT (14 to 15 per 1000, RR = 1.17 [1.14, 1.21]). While crude procedure rates were uniformly lower in PT, only CABG rates differed after standardization (2010: RR=0.19 [0.14, 0.26]). PCI use increased annually in both countries and decreased for CABG in the US only (102 to 79, RR=0.77 [0.73, 0.81]). Standardized in-hospital mortality decreased within-country (US: 44 to 29 per 1000, RR= 0.65 [0.60, 0.72]; PT: 93 to 62 per 1000, RR= 0.67 [0.44, 1.00]). In 2010, PT mortality was twice that in the US. Conclusions: AMI hospitalization rates and use of medical technologies are higher in the US compared to Portugal. However, standardized rates reveal only CABG surgery rates differ significantly between the two countries. Outcomes, measured by hospital mortality and LOS, are generally better in the U.S. Inter-country disparities may be a consequence of differential use of technologies, differences in AMI epidemiology, patient risk, or quality of hospital billing data.

Trends in and disparities for acute myocardial infarction: an analysis of Medicare claims data from 1992 to 2010

It is unknown whether previously reported disparities for acute myocardial infarction (AMI) by race and sex have declined over time. We used Medicare Part A administrative data files for 1992 to 2010 to evaluate changes in per-capita hospitalization rates for AMI, rates of revascularization (percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG)), and 30-day mortality for four distinct patient subcohorts: black women; black men; white women; and white men, adjusted for age, comorbidities and year using logistic regression. The study sample consisted of 4,045,267 AMI admissions between the years 1992 and 2010 (166,660 black women; 116,201 black men; 1,870,816 white women; 1,891,590 white men). AMI hospitalization rates differed significantly in 1992 to 1993 among black women (61.6 hospitalizations per 10,000 Medicare enrollees), black men (73.2 hospitalizations), white women (72.0 hospitalizations) and white men (113.2 hospitalizations) (P <0.0001). By 2009 to 2010 AMI hospitalization rates had declined substantially in all cohorts but disparities remained with significantly lower hospitalization rates among women and blacks compared to men and whites, respectively (P <0.0001). In multivariable-adjusted analyses, despite narrowing of the differences between cohorts over time, disparities in AMI hospitalization rates by race and sex remained statistically significant in 2009 to 2010 (P <0.001). In 1992 to 1993 and 2009 to 2010, rates of PCI within 30-days of AMI differed significantly among black women (8.6% in 1992 to 1993; 24.2% in 2009 to 2010), black men (10.4% and 32.6%), white women (12.8% and 30.5%), and white men (16.1% and 40.7%) (P <0.0001). In multivariable-adjusted analyses, racial disparities in procedure utilization appeared somewhat larger and sex-based disparities remained significant. Unadjusted 30-day mortality after AMI in 1992 to 1993 for black women, black men, white women and white men was 20.4%, 17.9%, 23.1% and 19.5%, respectively (P <0.0001); in 2009 to 2010 mortality was 17.1%, 15.3%, 18.2% and 16.2%, respectively (P <0.0001). In adjusted analyses, racial differences in mortality declined over time but differences by sex (higher mortality for women) persisted. Disparities in AMI have declined modestly, but remain a problem, particularly with respect to patient sex.

Do Younger Women Fare Worse? Sex Differences in Acute Myocardial Infarction Hospitalization and Early Mortality Rates Over Ten Years

Recent research has identified younger women as an "at-risk" population with rising prevalence of cardiac risk factors and excess mortality risk following acute myocardial infarction (AMI). However, population-based data on trends in AMI hospitalization and early mortality post AMI among younger adults is scarce. We, therefore, aimed to provide a 10-year, descriptive analysis of these trends in a Canadian setting. We assessed trends and sex differences in AMI hospitalization and 30-day mortality rates using negative binomial and logistic regression, respectively. From 2000 to 2009, there were 70,628 AMI hospitalizations in adults aged ≥20 years, in British Columbia, Canada, with 17.1% of cohort being younger adults ≤55 years. Overall, age-standardized AMI rates (per 100,000 population) declined similarly in men (295.8 to 247.7) and women (152.1 to 128.8) [sex-year interaction p=0.81]. However, these trends differed according to age (age-sex-year interaction p=0.02) with increased rates observed only in younger women (+1.7% per year; p=0.04). The 30-day mortality rates declined similarly for women (19.4% to 13.9%) and men (13.0% to 9.3%) (sex-year interaction p=0.33). Yet, younger women continued to have excess mortality risk, compared with younger men, even in the most recent period [odds ratio: (2008-09)=1.61 (95% onfidence interval: 1.25, 2.08)]. While the overall AMI hospitalization and 30-day mortality rates significantly declined in women and men, hospitalization rates in women ≤55 years increased and their excess risk of 30-day mortality persisted. These findings highlight the need to intensify strategies to reduce the incidence of AMI and improve outcomes after AMI in younger women.