Jorge L. Yarzebski

Temporal Trends in Cardiogenic Shock Complicating Acute Myocardial Infarction

BACKGROUND Limited information is available on trends in the incidence of and mortality due to cardiogenic shock complicating acute myocardial infarction. We studied the incidence of cardiogenic shock complicating acute myocardial infarction and in-hospital death rates among patients with this condition in a single community from 1975 through 1997. METHODS We conducted an observational study of 9076 residents of metropolitan Worcester, Massachusetts, who were hospitalized with confirmed acute myocardial infarction in all local hospitals during 11 one-year periods between 1975 and 1997. Our study included periods before and after the advent of reperfusion therapy. RESULTS The incidence of cardiogenic shock remained relatively stable over time, averaging 7.1 percent among patients with acute myocardial infarction. The results of a multivariable regression analysis indicated that the patients hospitalized during recent study years were not at a substantially lower risk for shock than patients hospitalized in the mid-to-late 1970s. Patients in whom cardiogenic shock developed had a significantly greater risk of dying during hospitalization (71.7 percent) than those who did not have cardiogenic shock (12.0 percent, P<0.001). A significant trend toward an increase in in-hospital survival among patients with cardiogenic shock in the mid-to-late 1990s was found in crude and adjusted analyses. CONCLUSIONS Our findings indicate no significant change in the incidence of cardiogenic shock complicating acute myocardial infarction over a 23-year period. However, the short-term survival rate has increased in recent years at the same time as the use of coronary reperfusion strategies has increased.

Thirty-year trends (1975 to 2005) in the magnitude of, management of, and hospital death rates associated with cardiogenic shock in patients with acute myocardial infarction: a population-based perspective

Background— Limited information is available about potentially changing and contemporary trends in the incidence and hospital death rates of cardiogenic shock complicating acute myocardial infarction. The objectives of our study were to examine 3-decade-long trends (1975 to 2005) in the incidence rates of cardiogenic shock complicating acute myocardial infarction, patient characteristics and treatment practices associated with this clinical complication, and hospital death rates in residents of a large central New England community hospitalized with acute myocardial infarction at all area medical centers. Methods and Results— The study population consisted of 13 663 residents of the Worcester (Mass) metropolitan area hospitalized with acute myocardial infarction at all greater Worcester medical centers during 15 annual periods between 1975 and 2005. Overall, 6.6% of patients developed cardiogenic shock during their index hospitalization. The incidence rates of cardiogenic shock remained stable between 1975 and the late 1990s but declined in an inconsistent manner thereafter. Patients in whom cardiogenic shock developed had a significantly greater risk of dying during hospitalization (65.4%) than those who did not develop cardiogenic shock (10.6%) (P<0.001). Encouraging increases in hospital survival in patients with cardiogenic shock, however, were observed from the mid-1990s to our most recent study years. Several patient demographic and clinical characteristics were associated with an increased risk for developing cardiogenic shock. Conclusions— Our findings indicate improving trends in the hospital prognosis associated with cardiogenic shock. Given the high death rates associated with this clinical complication, monitoring future trends in the incidence and death rates and the factors associated with an increased risk for developing cardiogenic shock remains warranted.

Recent Trends in the Incidence, Treatment, and Outcomes of Patients with STEMI and NSTEMI

BACKGROUND despite the widespread use of electrocardiographic changes to characterize patients presenting with acute myocardial infarction, little is known about recent trends in the incidence rates, treatment, and outcomes of patients admitted for acute myocardial infarction further classified according to the presence of ST-segment elevation. The objectives of this population-based study were to examine recent trends in the incidence and death rates associated with the 2 major types of acute myocardial infarction in residents of a large central Massachusetts metropolitan area. METHODS We reviewed the medical records of 5383 residents of the Worcester (MA) metropolitan area hospitalized for either ST-segment elevation acute myocardial infarction (STEMI) or non-ST-segment acute myocardial infarction (NSTEMI) between 1997 and 2005 at 11 greater Worcester medical centers. RESULTS the incidence rates (per 100,000) of STEMI decreased appreciably (121 to 77), whereas the incidence rates of NSTEMI increased slightly (126 to 132) between 1997 and 2005. Although in-hospital and 30-day case-fatality rates remained stable in both groups, 1-year postdischarge death rates decreased between 1997 and 2005 for patients with STEMI and NSTEMI. CONCLUSIONS the results of this study demonstrate recent decreases in the magnitude of STEMI, slight increases in the incidence rates of NSTEMI, and decreases in long-term mortality in patients with STEMI and NSTEMI. Our findings suggest that acute myocardial infarction prevention and treatment efforts have resulted in favorable decreases in the frequency of STEMI and death rates from the major types of acute myocardial infarction.

Sex Differences in 2-Year Mortality after Hospital Discharge for Myocardial Infarction

The issue of whether women have more unfavorable short-term outcomes than men after acute myocardial infarction has elicited considerable debate (1-6). In a recent study, we demonstrated an important interaction between sex and age that affected hospital mortality after myocardial infarction (7, 8). We found that younger, but not older, women have higher mortality rates than men of similar age. The risk among women increases linearly with decreasing age and is not fully explained by differences in clinical presentation or treatment (8). In contrast to short-term mortality studies, most studies examining long-term outcomes among survivors of the acute phase (hospitalization or the first month thereafter) have generally found no differences in mortality between men and women, and some have found that women have a more favorable outcome (5, 6, 9-22). However, these studies did not examine whether the association of sex with mortality changes according to age. An increased long-term risk for death among younger women may well be masked by the combined examination of all age groups. We examined survivors of the acute infarction episode to determine whether younger, but not older, women have a greater risk for death after hospital discharge than men of similar age. The Worcester Heart Attack Study is an ideal population in which to test this hypothesis, since it is a large community-based registry that involves long-term follow up of patients of different ages. Methods Study Sample The study sample consisted of 8277 residents of the Worcester, Massachusetts, standard metropolitan statistical area who were hospitalized for a confirmed myocardial infarction in any of the 16 community and teaching hospitals serving this region during 10 calendar years (1975, 1978, 1981, 1984, 1986, 1988, 1990, 1991, 1993, and 1995). All hospitals in this geographic area participated in this study. The medical records of all patients who were assigned a primary or secondary discharge diagnosis of myocardial infarction were individually reviewed, and the diagnosis was confirmed according to preestablished criteria, as described elsewhere (16, 23, 24). Cases of perioperative myocardial infarction were not included. For the analysis of long-term survival after discharge, we excluded 1366 patients who died during the index hospitalization. An additional 85 patients (1.2% of the hospital survivors) were excluded because vital status at follow-up was unknown. Therefore, 6826 patients who survived the index hospitalization were available for analysis. Data Collection Demographic characteristics, medical history, clinical characteristics of the infarction, hospital complications, and use of treatments and interventional procedures were abstracted from the medical records as described elsewhere (16, 24-27). Vital status after discharge was ascertained by a review of medical records for subsequent hospitalizations and a statewide and national search of death certificates for metropolitan Worcester residents (23, 24, 27). The outcome of our study was survival status 2 years after hospital discharge, since all patients in the current analysis had reached at least the 2-year anniversary. Statistical Analysis Before excluding in-hospital deaths, we compared hospital mortality in women and men according to 10-year age groupings. The effect of the interaction between age and sex on hospital mortality was tested in a logistic regression model by using the likelihood ratio test. In the sample of hospital survivors, we compared baseline characteristics, hospital events, and treatments between women and men in three collapsed age groups (<60 years, 60 to 69 years, 70 years) that corresponded to approximate tertiles of the age distribution. Collapsed age groups were used to allow sufficient cell numbers for all comparisons. We used life-table methods (28) to compare cumulative all-cause mortality from hospital discharge to 2 years after stratification according to the three age groups. Finally, to assess the impact of groups of variables on the associations of interest (sex and the effect of its interaction with age on mortality), we conducted a series of Cox proportional-hazards regression models for 2-year mortality after hospital discharge. Hazard ratios and accompanying 95% CIs for sex were calculated according to age from the Cox models. The first model included sex and age as explanatory variables. In the second model, the interaction between sex and age was added. In a subsequent model, we added other demographic factors (ethnicity and marital status) and medical history (history of infarction, angina, congestive heart failure, diabetes, stroke, and hypertension). In a final model, we added clinical characteristics of the infarction (Q-wave infarction and anterior infarction), hospital complications (congestive heart failure, cardiogenic shock, stroke, atrioventricular block, and ventricular tachycardia or fibrillation), hospital treatments and procedures (thrombolytic therapy, coronary angiography, coronary bypass, and coronary angioplasty), and discharge treatments (antiplatelet medications, -blockers, diuretics, digoxin, angiotensin-converting enzyme inhibitors, calcium-channel blockers, and nitrates). Potential confounding by hospital and by discharge year were addressed by refitting the final model with these variables, respectively, as stratification factors. Because studies have reported that diabetes may be a stronger risk factor for death in women than in men after myocardial infarction (29-32), the effect of the interaction between sex and diabetes on mortality rate was also tested. Linearity of age and of the interaction between age and sex was checked by fitting age and the agesex interaction both as categorical variables and as linear terms in the proportional hazards models. Age and its interaction with sex were ultimately modeled as continuous variables (in years) because no significant departure from linear trend was found. The hazard ratio of 2-year death for women compared with men was calculated according to 10-year age decrements (from old to young). Multivariable results were also examined in terms of risk differences between men and women according to age by deriving the predicted probabilities at 24 months from Cox proportional-hazards models in the three age groups. Covariable levels were standardized to the distribution of the entire study sample (33). To avoid model overfitting, given the smaller sample size in the age-stratified models, control factors in these analyses were limited to demographic characteristics and medical history. The proportional hazards assumption was checked by testing the significance of the interaction between main predictor variables and time. All tests of statistical significance were two tailed, and all analyses were performed by using SAS, version 6.12 (SAS Institute, Inc., Cary, North Carolina). Results Hospital Mortality Of 8277 patients with confirmed acute myocardial infarction, 1366 died during the index hospitalization. Overall, the hospital mortality rate was significantly higher in women (20.9%) than in men (13.6%) (P =0.01). As expected, sex differences in hospital mortality varied according to age. In persons younger than 50 years of age, women had an almost threefold higher risk for death than men. The odds ratio of hospital death for women compared with men decreased with advancing age and was close to 1.00 among patients at least 70 years of age. Baseline Sex Differences in Hospital Survivors Among the 6826 hospital survivors with known vital status at follow-up, women were significantly older than men overall (mean age, 71.4 years vs. 63.2 years; P <0.001). In all age groups, women were less likely to be married and more likely to have a history of heart failure and hypertension (Table 1). Younger women, but not older women, were more likely than men of similar age to have a history of diabetes and stroke and to have experienced an anterior infarction during the index admission. However, at all ages, men were more likely than women to have a history of myocardial infarction and to have had a Q-wave infarction during the index hospitalization. Women, especially those younger than 60 years of age, experienced more heart failure and heart block, but men more often had complicating ventricular arrhythmias during the index hospitalization. Sex differences in treatments and procedures during hospitalization were small. At discharge, women were less likely than men to be prescribed -blockers but were more likely to receive diuretics and digoxin. Similar proportions of men and women were included in different discharge years. Table 1. Comparison of Baseline Characteristics between Women and Men according to Age Sex Differences in 2-Year Mortality among Hospital Survivors At 2 years after hospital discharge, 1577 patients had died (748 women [28.9%] and 829 men [19.6%]; hazard ratio for women compared with men, 1.47 [95% CI, 1.35 to 1.61]). However, when patients were examined by age group (Table 2 and Figure), only women younger than 60 years of age had a higher mortality rate than men of similar age. Sex differences in mortality rate decreased with advancing age, and among the oldest patients, women tended to have lower mortality rates than men. Results were consistent when examined in terms of risk difference (Table 2). The absolute risk for women compared with men was highest in patients younger than 60 years of age, while the absolute risk was lower for women among patients at least 80 years of age. As expected, given the higher mortality rates of older patients, the risk difference between women and men at older ages was larger than the risk difference at younger ages. Because women were older than men within each age interval shown in the Figure, the curves for cumulative mortality rate were adjusted for age (with age as a continuous variable). The hazard ratio of death for women co

A two-decades (1975 to 1995) long experience in the incidence, in-hospital and long-term case–fatality rates of acute myocardial infarction: a community-wide perspective☆

OBJECTIVES The purpose of the present study is to describe changes over two decades (1975 to 1995) in the incidence, in-hospital and long-term case-fatality rates associated with acute myocardial infarction (AMI) from a multihospital community-wide perspective. BACKGROUND Despite the magnitude of, and mortality associated with acute myocardial infarction (AMI), relatively limited population-based data are available to describe recent and temporal trends in the attack and case-fatality rates associated with AMI from a representative population-based perspective. METHODS The community-based study included 5,270 residents of the Worcester, Massachusetts, metropolitan area hospitalized with confirmed initial AMI in all metropolitan Worcester, Massachusetts, hospitals (1990 census population = 437,000) in 10 one-year periods between 1975 and 1995. RESULTS The age-adjusted incidence rates of initial AMI increased between 1975 (244 per 100,000) and 1981 (272 per 100,000), after which time these rates declined through 1995 (184 per 100,000). The crude and multivariable-adjusted in-hospital case-fatality rates exhibited a consistent decline between 1975/1978 (17.8%), 1986/1988 (17.0%) and 1993/1995 (11.7%). Although there were no statistically significant differences in the unadjusted long-term case-fatality rates of discharged hospital survivors over the periods under study, declines in the multivariable-adjusted risk of dying within the first year after hospital discharge were observed between the earliest and most recently discharged patients with AMI. CONCLUSIONS The results of this population-based study of patients with validated initial AMI provide encouragement for efforts directed at the primary and secondary prevention of AMI given declining incidence and case-fatality rates.

A communitywide perspective of sex differences and temporal trends in the incidence and survival rates after acute myocardial infarction and out-of-hospital deaths caused by coronary heart disease.

BackgroundThe purpose of the study was to examine overall differences and temporal trends therein between men and women regarding the incidence rates, in-hospital and long-term survival after initial acute myocardial infarction (AMI), and out-of-hospital deaths caused by coronary disease Methods and ResultsThis nonconcurrent prospective study was carried out in 16 teaching and community hospitals in Worcester, Mass., in six time periods between 1975 and 1988. A total of 3,148 patients hospitalized with validated initial AMI comprised the study sample. The age-adjusted incidence rates of initial AMI increased between 1975 and 1981 in the two sexes, with a marked decrease thereafter, these rates declined by 26% in men and by 22% in women between 1975 and 1988. The overall unadjusted in-hospital case-fatality rates after initial AMI were significantly higher in women (21.7%) than in men (12.7%). Age- and multivariable-adjusted in-hospital case-fatality rates, however, were not significantly different for men compared with women (multivariate-adjusted OR, 0.90; 95% CI, 0.70, 1.16). No clear trends in in-hospital case-fatality rates were observed in men or women over the periods under study. There were no significant sex differences in the age-adjusted long-term survival rates of discharged hospital survivors of AMI. The multivariate-adjusted risk of total mortality among discharged hospital survivors, however, was significantly increased in men (multivariate-adjusted OR, 1.20; 95% CI, 1.03, 1.39); neither of the sexes experienced an improvement over time in long-term prognosis. The incidence rates of out-of-hospital deaths caused by coronary disease declined by 60%o in men and 69%o in women between 1975 and 1988. ConclusionThe results of this multihospital, community-based study suggest declines in the incidence rates of AMI and out-of-hospital deaths caused by coronary disease in men and women over the period under study (1975–1988). No significant sex differences in in-hospital survival were observed, whereas a poorer long-term survival experience after hospital discharge was observed for men compared with women after controlling for potentially confounding prognostic factors. (Circulation 1993;87:1947-1953)

Twenty Year Trends (1975-1995) in the Incidence, In-hospital and Long-Term Death Rates Associated With Heart Failure Complicating Acute Myocardial Infarction A Community-Wide Perspective

OBJECTIVES To describe from a population-based perspective, recent and temporal (1975-1995) trends in the incidence, in-hospital and postdischarge case-fatality rates of heart failure (HF) complicating acute myocardial infarction (AMI). BACKGROUND Extremely limited data are available describing the incidence and case-fatality rates associated with HF complicating AMI from a community-wide perspective. METHODS The medical records of 6,798 residents of the Worcester, Massachusetts metropolitan area with validated MI and without previous HF hospitalized in 10 annual periods between 1975 and 1995 were reviewed. RESULTS The proportion of AMI patients developing HF during hospitalization declined between 1975-1978 (38%) and 1993-1995 (33%) (p < 0.001). After controlling for potentially confounding factors, the risk of developing HF declined progressively, albeit modestly, over time. In-hospital case-fatality rates of patients with AMI complicated by HF declined by approximately 46% between 1975-1978 (33%) and 1993-1995 (18%) (p < 0.001). Improving trends in hospital survival were observed after adjusting for potentially confounding prognostic factors. The one-year post-discharge mortality rate for hospital survivors of HF did not change over the 20-year period under study, even after controlling for additional prognostic characteristics. CONCLUSIONS The results of this community-wide study suggest encouraging declines in the incidence and hospital death rates associated with HF complicating AMI. Continued efforts need to be directed towards the prevention of HF given the magnitude of this clinical syndrome. Efforts of secondary prevention are needed to identify and improve the treatment of patients with symptomatic left ventricular dysfunction following AMI given the lack of improvement in the long-term prognosis of these patients.

Age-related trends in short- and long-term survival after acute myocardial infarction: a 20-year population-based perspective (1975–1995)

This study examines age-related differences and temporal trends in hospital and long-term survival after acute myocardial infarction (AMI) over a 2-decade-long (1975 to 1995) experience. A total of 8,070 patients with validated AMI hospitalized in all acute care hospitals in the Worcester, Massachusetts, metropolitan area (1990 census population 437,000) were studied over 10 one-year periods between 1975 and 1995. This population included 1,326 patients aged <55 years (16.4%), 1,768 patients aged 55 to 64 years (21.9%), 2,325 patients aged 65 to 74 years (28.8%), 1,880 patients aged 75 to 84 years (23.3%), and 771 patients aged > or = 85 years (9.6%). Compared with patients <55 years, patients 55 to 64 years were 2.2 times more likely to die during hospitalization for AMI, whereas patients 65 to 74, 75 to 84, and > or = 85 years were at 4.2, 7.8, and 10.2 times greater risk of dying, respectively. Similar age disparities in the risk of dying were seen when controlling for additional prognostic factors. Despite the adverse impact of increasing age on hospital survival after AMI, declining in-hospital death rates were seen in each of the age groups under study, with declining magnitude of these trends with advancing age. Among discharged hospital patients, increasing age was related to a significantly poorer long-term prognosis. Trends toward improving long-term prognosis were seen in patients discharged in the mid-1990s compared with those discharged in the mid- to late 1970s for patients aged <85 years. The present results demonstrate the marked impact of advancing age on survival after AMI. Despite the adverse impact of age on prognosis, encouraging trends in prognosis were observed in all age groups, although to a lesser extent in the oldest elderly patients. These findings emphasize the low death rates in middle-aged patients with AMI and the need for targeted secondary prevention efforts in elderly patients with AMI.

A 30-Year Perspective (1975–2005) Into the Changing Landscape of Patients Hospitalized With Initial Acute Myocardial Infarction Worcester Heart Attack Study

Background—The effects of lifestyle changes and evolving treatment practices on coronary disease incidence rates, demographic and clinical profile, and the short-term outcomes of patients hospitalized with acute myocardial infarction have not been well characterized. The purpose of this study was to examine multidecade-long trends (1975–2005) in the incidence rates, demographic and clinical characteristics, treatment practices, and hospital outcomes of patients hospitalized with an initial acute myocardial infarction from a population-based perspective. Methods and Results—Residents of the Worcester, Mass, metropolitan area (median age, 37 years; 89% white) hospitalized with an initial acute myocardial infarction (n=8898) at all greater-Worcester medical centers during 15 annual periods between 1975 and 2005 comprised the sample of interest. The incidence rates of initial acute myocardial infarction were lower in 2005 (209 of 100 000 population) than in 1975 (277 of 100 000), although these trends varied inconsistently over time. Patients hospitalized during the most recent study years were significantly older (mean age, 64 years in 1975; 71 years in 2005), more likely to be women (38% in 1975; 48% in 2005), and have a greater prevalence of comorbidities. Hospitalized patients were increasingly more likely to receive effective cardiac medications and coronary interventional procedures for the period under investigation. Hospital survival rates improved significantly over time (81% survived in 1975; 91% survived in 2005), although varying trends were observed in the occurrence of clinically important complications. Conclusions—The results of this community-wide investigation provide insight into the changing magnitude, characteristics, management practices, and outcomes of patients hospitalized with a first myocardial infarction.

Effect of Elevated Leukocyte Count on In-Hospital Mortality Following Acute Myocardial Infarction *

The peripheral white blood cell count on presentation with acute myocardial infarction directly correlates with short-term in-hospital mortality. This association is independent of other prognostic factors, including extent and size of the acute myocardial infarction.