Robert J. McCarter

Effect of beta-blockade on mortality among high-risk and low-risk patients after myocardial infarction.

BACKGROUND Long-term administration of beta-adrenergic blockers to patients after myocardial infarction improves survival. However, physicians are reluctant to administer beta-blockers to many patients, such as older patients and those with chronic pulmonary disease, left ventricular dysfunction, or non-Q-wave myocardial infarction. METHODS The medical records of 201,752 patients with myocardial infarction were abstracted by the Cooperative Cardiovascular Project, which was sponsored by the Health Care Financing Administration. Using a Cox proportional-hazards model that accounted for multiple factors that might influence survival, we compared mortality among patients treated with beta-blockers with mortality among untreated patients during the two years after myocardial infarction. RESULTS A total of 34 percent of the patients received beta-blockers. The percentage was lower among the very elderly, blacks, and patients with the lowest ejection fractions, heart failure, chronic obstructive pulmonary disease, elevated serum creatinine concentrations, or type 1 diabetes mellitus. Nevertheless, mortality was lower in every subgroup of patients treated with beta-blockade than in untreated patients. In patients with myocardial infarction and no other complications, treatment with beta-blockers was associated with a 40 percent reduction in mortality. Mortality was also reduced by 40 percent in patients with non-Q-wave infarction and those with chronic obstructive pulmonary disease. Blacks, patients 80 years old or older, and those with a left ventricular ejection fraction below 20 percent, serum creatinine concentration greater than 1.4 mg per deciliter (124 micromol per liter), or diabetes mellitus had a lower percentage reduction in mortality. Given, however, the higher mortality rates in these subgroups, the absolute reduction in mortality was similar to or greater than that among patients with no specific risk factors. CONCLUSIONS After myocardial infarction, patients with conditions that are often considered contraindications to beta-blockade (such as heart failure, pulmonary disease, and older age) and those with nontransmural infarction benefit from beta-blocker therapy.

Cerebral infarction in young adults The Baltimore-Washington Cooperative Young Stroke Study

Background: Few reports on stroke in young adults have included cases from all community and referral hospitals in a defined geographic region. Methods: At 46 hospitals in Baltimore City, 5 central Maryland counties, and Washington, DC, the chart of every patient 15 to 44 years of age with a primary or secondary diagnosis of possible cerebral arterial infarction during 1988 and 1991 was abstracted. Probable and possible etiologies were assigned following written guidelines. Results: Of 428 first strokes, 212 (49.5%) were assigned at least one probable cause, 80 (18.7%) had no probable cause but at least one possible cause, and 136 (31.8%) had no identified probable or possible cause. Of the 212 with at least one probable cause, the distribution of etiologies was cardiac embolism(31.1%), hematologic and other (19.8%), small vessel (lacunar) disease(19.8%), nonatherosclerotic vasculopathy (11.3%), illicit drug use (9.4%), oral contraceptive use (5.2%), large artery atherosclerotic disease (3.8%), and migraine (1.4%). There were an additional 69 recurrent stroke patients. Conclusions: In this hospital-based registry within a region characterized by racial/ethnic diversity, cardiac embolism, hematologic and other causes, and lacunar stroke were the most common etiologies of cerebral infarction in young adults. Nearly a third of both first and recurrent strokes had no identified cause.

Smoking, body mass, and hot flashes in midlife women☆

OBJECTIVE To assess whether lifestyle factors, specifically smoking and body mass index (BMI), are associated with the occurrence of any, moderate to severe, or daily hot flashes. METHODS A cross-sectional study was conducted among women aged 40–60 years residing in the Baltimore metropolitan area who reported their history of hot flashes through a mailed survey. Logistic regression was used to assess the associations between smoking and BMI with any, moderate to severe, and daily hot flashes. RESULTS Of the 1087 women included in the study, 56% reported having hot flashes. Compared with never-smokers, current smokers were at an increased risk for both moderate to severe hot flashes (adjusted odds ratio [OR] = 1.9, 95% confidence interval [CI] 1.3, 2.9) and daily hot flashes (adjusted OR = 2.2, 95% CI 1.4, 3.7). Among current smokers, risk for hot flashes increased with greater amount smoked. High BMI (more than 30 kg/m2) was associated with an increased risk for moderate to severe hot flashes compared with low BMI (less than 24.9 kg/m2) (adjusted OR = 2.1, 95% CI 1.5, 3.0). An increased risk for any or daily hot flashes with high BMI was present only among premenopausal or perimenopausal women. CONCLUSION Potentially modifiable factors, such as current smoking and high BMI, may predispose a woman to more severe or frequent hot flashes. This information may be valuable for identifying women at risk for hot flashes and for developing appropriate prevention strategies that may include lifestyle modifications.

High and low hemoglobin glycation phenotypes in type 1 diabetes A challenge for interpretation of glycemic control

This study tested the hypothesis that there are consistent individual differences in the relationship between glycated hemoglobin (HbA1c) and mean blood glucose (MBG) levels in individuals with similar preceding blood glucose levels. Blood glucose data were collected for up to 2.3 years by 128 children and adolescents with type 1 diabetes. HbA1c values were date-matched with MBG levels calculated from an average of 85 self-monitored blood glucose measurements collected in the previous 30 days. There was significant linear correlation between MBG and HbA1c (HbA1c=0.027xMBG+5.8, n=682, r=.71, P<.0001) but also wide variability in the population HbA1c response to MBG. We calculated a hemoglobin glycation index (HGI=observed HbA1c-predicted HbA1c) to quantify the magnitude and direction of the difference between each patients set of observed and predicted HbA1c results. Likelihood ratio tests and t statistics showed that mean HGI were significantly different among individuals, and that 29% of the patients had HbA1c levels that were statistically significantly higher or lower than predicted by the regression equation. The observed individual differences in the relationship between MBG and HbA1c were not related to erythrocyte age and there was no evidence of analytical artifact. We interpret these results as possible evidence of high and low hemoglobin glycation phenotypes within the population. We conclude that MBG and HbA1c are not necessarily interchangeable estimates of glycemic control and that hemoglobin glycation phenotype may be important for the clinical assessment of diabetic patients.

Systemic inflammatory response syndrome score at admission independently predicts mortality and length of stay in trauma patients

BACKGROUND Recent studies have documented that the systemic inflammatory response syndrome (SIRS) score is a useful predictor of outcome in critical surgical illness. The duration and severity of SIRS are associated with posttrauma multiple organ dysfunction and mortality. We sought to determine whether the severity of SIRS at admission is an accurate predictor of mortality and length of stay (LOS) in trauma patients. METHODS Prospective data of 4,887 trauma admissions to a Level I trauma center over a 18-month period (January 1997 to July 1998) were analyzed. Patients were stratified by age and Injury Severity Score (ISS), and a SIRS severity score (1 to 4) was calculated at admission (1 point for each component present: fever or hypothermia, tachypnea, tachycardia, and leukocytosis). The SIRS score was evaluated as an independent predictor of mortality and LOS by chi2 and multivariate logistic regression. RESULTS Trauma patients (n = 4,887, 83% blunt injuries, 72% male) had the following characteristics: 73.1% were age 18 to 45 years, 17.5% were age 46 to 65 years, and 9.4% were age > or =66 years; 77.7% had ISS less than 15, 18.8% had ISS 16 to 29, and 3.5% had ISS greater than 29. Analysis of variance adjusting for age and ISS determined that SIRS score of 2 was a significant predictor of LOS. Furthermore, the relative risk of death increased significantly with SIRS score of 2 when age and ISS were held constant. CONCLUSION Logistic regression analysis confirmed that a SIRS score of 2 was a significant independent predictor of increased mortality and LOS in trauma patients. These data suggest that admission SIRS scoring in trauma patients is a simple tool that may be used as a predictor of outcome and resource utilization.

Male Gender Is Associated With Increased Risk For Postinjury Pneumonia

Nosocomial pneumonia in trauma patients is a significant source of resource utilization and mortality. We have previously described increased rates of pneumonia in male trauma patients in a single institution study. In that study, female trauma patients had a lower incidence of postinjury pneumonia but a higher relative risk for mortality when they did develop pneumonia. We sought to investigate the hypothesis that male trauma patients have an increased incidence of postinjury pneumonia in a separate population-based dataset. Prospective data were collected on 30,288 trauma patients (26,231 blunt injuries, 4057 penetrating injuries) admitted to all trauma centers (n = 26) in Pennsylvania over 24 months (January 1996 to December 1997). Gender differences in pneumonia were determined for the entire dataset. A second analysis examined all blunt injury patients and excluded all patients with a hospital length of stay less than 24 h, eliminating patients who expired early after admission. In trauma patients with minor injury (ISS < 15), there was no significant difference between male and female patients in the rate of postinjury pneumonia (male 1.37%, female 1.11%). In the moderate-injury group (ISS > 15), male trauma patients had a significantly increased incidence of postinjury pneumonia (ISS 15–30, male 8.85%, female 6.45%; ISS > 30, male 24.35%, female 17.30%). Logistic regression analysis of blunt trauma patients revealed that gender, ISS, injury type, admission Revised Trauma Score (RTS), admission respiratory rate, history of cardiac disease, and history of cancer were all independent predictors of pneumonia. Trauma patients with nosocomial pneumonia had a significantly higher mortality rate (P < 0.001) than patients without pneumonia. There was no gender-specific difference in mortality among pneumonia patients. Male gender is significantly associated with an increased incidence of postinjury pneumonia. In contrast to our initial study, there was no gender difference in postinjury pneumonia mortality rates identified in this population-based study.

Effects of exercise training on peak performance and quality of life in congestive heart failure patients.

BACKGROUND Exercise programs for patients with heart failure have often enrolled and evaluated relatively healthy, young patients. They also have not measured the impact of exercise performance on daily activities and quality of life. METHODS AND RESULTS We investigated the impact of a 6-month supervised and graded exercise program in 33 elderly patients with moderate to severe heart failure randomized to usual care or an exercise program. Six of 17 patients did not tolerate the exercise program. Of those who did, peak oxygen consumption increased by 2.4 +/- 2.8 mL/kg/min (P < .05) and 6-minute walk increased by 194 ft (P < .05). However, outpatient energy expenditure did not increase, as measured by either the doubly labeled water technique or Caltrac accelerometer. Perceived quality of life also did not improve, as measured by the Medical Outcomes Study, Functional Status Assessment, or Minnesota Living With Heart Failure questionnaires. CONCLUSION Elderly patients with severe heart failure can safely exercise, with an improvement in peak exercise tolerance. However, not all patients will benefit, and daily energy expenditure and quality of life do not improve to the same extent as peak exercise.

Prophylactic Chlorhexidine Oral Rinse Decreases Ventilator-Associated Pneumonia in Surgical ICU Patients

BACKGROUND Pneumonia is one of the most common nosocomial infections in hospitalized patients. The risk of nosocomial pneumonia increases with age, severity of acute illness and preexisting co-morbid conditions. Ventilator-associated pneumonia (VAP) significantly increases morbidity, length of stay, resource utilization and mortality. The purpose of this study was to determine whether adherence to a ventilator weaning protocol (WP) and the use of chlorhexidine gluconate (CH) oral rinse for oral hygiene would decrease the incidence of VAP in surgical ICU patients. METHODS A prospective study was conducted over a period of 10 months (October 1998-July 1999) in surgical ICU patients requiring mechanical ventilation (n = 95). During the first 5 months, a WP was applied to all patients requiring mechanical ventilation. During the following 5 months, a CH 0.12% oral rinse administered twice daily was added to the protocol, initiated on ICU admission in all intubated patients. The data collection included age, gender, race, risk factors, co-morbid conditions, severity of the acute illness (APACHE II) at admission, duration of ventilation, ICU and total-hospital length of stay, and incidence of VAP and in-hospital mortality rates. Both WP and WP+CH groups were compared using the National Nosocomial Infection Surveillance (NNIS) and hospital databases as historic controls. RESULTS The institution of the WP alone led only to a slight decrease in the incidence of VAP but a significant reduction in the median duration of mechanical ventilation by 40% (4.5 days, p < 0.008). The addition of CH to the WP led to a significant reduction and delay in the occurrence of VAP (37% overall, 75% for late VAP, p < 0.05). The median duration of mechanical ventilation in this group was similar to that of the WP group. There was no significant difference in the overall hospital or ICU length of stay between the groups. CONCLUSIONS Improved oral hygiene via topical CH application in conjunction with the use of a WP is effective in reducing the incidence of VAP and the duration of mechanical ventilation in surgical ICU patients.

Back to basics : Validation of the admission systemic inflammatory response syndrome score in predicting outcome in trauma

BACKGROUND We have previously documented that the admission systemic inflammatory response syndrome (SIRS) score, calculated with four variables-temperature, heart rate, neutrophil count, and respiratory rate-is a significant predictor of outcome in trauma (n = 4,887). The objective of this current study was to validate our previous findings in a larger trauma patient population, to analyze the predictive accuracy of the four individual components of the SIRS score (temperature, heart rate, neutrophil count, and respiratory rate), and to assess whether the admission SIRS score is an accurate predictor of intensive care unit (ICU) resource use in trauma. METHODS Prospective data were collected on 9,539 patients admitted to a Level I trauma center over a 30-month period (January 1997-July 1999). Patients were stratified by age, sex, race, and Injury Severity Score (ISS). SIRS score was calculated at admission, and SIRS was defined as a SIRS score > or = 2. RESULTS SIRS score was validated as a significant independent predictor of outcome in trauma by logistic regression analysis after controlling for age and ISS. Of the four SIRS variables, hypothermia (temperature < 36 degrees C) was the most significant predictor of mortality after controlling for age and ISS. Leukocytosis (neutrophil count > 12,000/mm3) was the most significant predictor of total hospital length of stay. SIRS scores of > or = 2 were increasingly predictive of mortality and ICU admission by logistic regression analysis (p < 0.001). CONCLUSION These data provide further validation that an admission SIRS score of > or = 2 is a significant independent predictor of outcome and ICU resource use in trauma. Temperature (hypothermia) is the individual component of the SIRS score with the greatest predictive accuracy. SIRS score should be calculated on all trauma admissions.

Platelet Glycoprotein Receptor IIIa Polymorphism P1A2 and Ischemic Stroke Risk: The Stroke Prevention in Young Women Study

BACKGROUND AND PURPOSE Platelet glycoprotein IIb/IIa (GpIIb-IIIa), a membrane receptor for fibrinogen and von Willebrand factor, has been implicated in the pathogenesis of acute coronary syndromes but has not been previously investigated in relation to stroke in young adults. METHODS We used a population-based case-control design to examine the association of the GpIIIa polymorphism P1A2 with stroke in young women. Subjects were 65 cerebral infarction cases (18 patients with and 47 without an identified probable etiology) 15 to 44 years of age from the Baltimore-Washington region and 122 controls frequency matched by age from the same geographic area. A face-to-face interview for vascular disease risk factors and a blood sample for the P1A2 allele and serum cholesterol were obtained from each participant. Logistic regression was used to estimate the odds ratio for one or more P1A2 alleles after adjustment for other risk factors. RESULTS Among cases and controls, the prevalence rates of one or more P1A2 alleles were 21% and 22% among blacks and 36% and 28% among whites, respectively. This genotype was significantly associated with hypertension only in black control subjects but otherwise not with any of the established vascular risk factors. The adjusted odds ratio for cerebral infarction of one or more P1A2 alleles was 1.1 (confidence interval [CI], 0.6 to 2.3) overall, 0.5 (CI, 0.1 to 7.1) among blacks, and 1.4 (CI, 0.5 to 3.7) among whites. For the cases with an identified probable etiology, the corresponding odds ratios were 3.0 (CI, 0.9 to 10.4) overall, 0.7 (CI, 0.1 to 7.1) among blacks, and 12.8 (CI, 1.2 to 135.0) among whites. CONCLUSIONS No association was found between the P1A2 polymorphism of GpIIIa and young women with stroke. However, subgroup analyses showed that the P1A2 polymorphism of GpIIIa appeared to be associated with stroke risk among white women, particularly those with a clinically identified probable etiology for their stroke. Further work with an emphasis on stroke subtypes and with multiracial populations is warranted.