Dental composites and amalgam and physical development in children.

Resin-based composite dental restoration materials may release bisphenol-A, an endocrine-disrupting chemical. Using secondary analysis of a randomized clinical safety trial of amalgam vs. composites, we tested the hypothesis that dental restoration materials affect children's growth. Children (N = 218 boys, N = 256 girls) aged 6 to 10 yrs at baseline with ≥ 2 decayed posterior teeth were randomized to amalgam or composites (bisphenol-A-diglycidyl-dimethacrylate composite for permanent teeth, urethane-dimethacrylate compomer for primary teeth) for treatment of posterior caries throughout follow-up. Primary outcomes for this analysis were 5-year changes in BMI-for-age z-scores, body fat percentage (BF%), and height velocity; exploratory analyses (n = 113) examined age at menarche. Results showed no significant differences between treatment assignment and changes in physical development in boys [(composites vs. amalgam) BF%, 4.9 vs. 5.7, p = 0.49; (BMI-z-score) 0.13 vs. 0.25, p = 0.36] or girls (8.8 vs. 7.7, p = 0.95; 0.36 vs. 0.21, p = 0.49). Children with more treatment on primary teeth had greater increases in BF% regardless of material type. Girls assigned to composites had lower risk of menarche during follow-up (hazard ratio = 0.57, 95% CI 0.35-0.95). Overall, there were no significant differences in physical development over 5 years in children treated with composites or amalgam. Additional studies examining these restoration materials in relation to age at menarche are warranted (clinicaltrials.gov number NCT00065988).

Dental amalgam and psychosocial status: the New England Children's Amalgam Trial.

High-dose exposures to elemental mercury vapor cause emotional dysfunction, but it is uncertain whether the levels of exposure that result from having dental amalgam restorations do so. As part of the New England Children's Amalgam Trial, a randomized trial involving 6- to 10-year-old children, we evaluated the hypothesis that restoration of caries using dental amalgam resulted in worse psychosocial outcomes than restoration using mercury-free composite resin. The primary outcome was the parent-completed Child Behavior Checklist. The secondary outcome was children's self-reports using the Behavior Assessment System for Children. Children's psychosocial status was evaluated in relation to three indices of mercury exposure: treatment assignment, surface-years of amalgam, and urinary mercury excretion. All significant associations favored the amalgam group. No evidence was found that exposure to mercury from dental amalgams was associated with adverse psychosocial outcomes over the five-year period following initial placement of amalgams.

The influence of esmolol on the dose of propofol required for induction of anaesthesia.

Cardiac output may be an important determinant of the induction dose of intravenous anaesthetic. Esmolol is known to reduce cardiac output, and we examined its effect on the propofol dose required for induction of anaesthesia. The size of the effect seen with esmolol was compared with midazolam co-induction. Sixty patients were randomly allocated to placebo (saline), esmolol (1mg x kg(-1) bolus, followed by an infusion at 250 microg x kg(-1)min(-1)) or midazolam (0.04 mg x kg(-1)) groups. Induction of anaesthesia commenced 3 min following the administration of the study drug, using a Diprifusor set to achieve plasma propofol concentrations of 10 microg x ml(-1) at 5 min. The primary end point used was the propofol dose per kg at loss of response to command. The mean (SD) propofol dose for each group was 2.38 (0.48) mg x kg(-1) for placebo, 1.79 (0.36) mg x kg(-1) for esmolol and 1.34 (0.35) mg x kg(-1) for midazolam (all means significantly different; p < 0.0005). We found that predosing with esmolol reduces the propofol requirements for induction of anaesthesia by 25%.

Coronary heart disease surveillance: field application of an epidemiologic algorithm.

This report describes the performance of a surveillance system and computerized algorithm for the assignment of definite or probable hospitalized cardiac events for large epidemiologic studies. The algorithm, developed by the Coordinating Committee for Community Demonstration Studies (CCCDS), evolved from the Gillum criteria, and included selected ICD-9-CM codes including codes 410 through 414 for discharge record screening, plus creatine kinase. For the small percentage of cases in which enzyme analysis was inconclusive (8%), presence of pain and/or Minnesota-coded electrocardiograms were included to define the outcome. All data items were easily obtained from medical records by trained lay record abstractors and required no interpretation. From January 1980 through December 1991, 21,183 medical records were screened for ICD-9-CM codes 410 through 414. Of all 410 to 411 ICD-9-CM codes (n = 9026), 36.9% (n = 3220) were classified as definite cardiac events and 10.6% (n = 1057) as probable events. Of all 412 through 414 codes (n = 9070), only 1.8% (n = 227) were classified as definite cardiac events and 5.4% (n = 716) as probable events. The epidemiologic diagnostic algorithm presented in this article used computerized data to assign diagnoses in a standard, objective manner, and was a lower cost alternative to classification of cardiac events on the basis of clinical review and/or more complex record abstraction approaches.

A longitudinal study of weight and the menopause transition: results from the Massachusetts Women's Health Study.

OBJECTIVE: Results of past studies of menopause and weight are inconsistent, in part because of problems in study design and analyses, such as retrospective assessment of age at menopause and failure to control for confounding factors. To address such shortcomings, we conducted multivariate analyses on longitudinal data from a large, community-based sample of initially pre- and perimenopausal women who were making the transition through menopause. DESIGN: Data were from the second phase of the Massachusetts Women's Health Study, a cohort of 418 women aged 50-60 years in 1986. We assessed the relationship between menopause transition and weight, after accounting for previous weight; age; and the behavioral factors of smoking, exercise, and annual ethanol consumption. Menopause status was defined in terms of months of amenorrhea. The association of hormone replacement therapy and weight also was examined. RESULTS: Menopause transition was not consistently associated with increased weight, and use of hormone replacement therapy was not significantly related to weight. Behavioral factors--particularly exercise and ethanol consumption--were more strongly related to weight than was menopause transition. CONCLUSIONS: These results are consistent with findings from other studies that suggest that the weight increases experienced by middle-aged women in the United States are not a result of the menopause transition.

Early revascularization in acute myocardial infarction complicated by cardiogenic shock. SHOCK Investigators. Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock.

BACKGROUND: The leading cause of death in patients hospitalized for acute myocardial infarction is cardiogenic shock. We conducted a randomized trial to evaluate early revascularization in patients with cardiogenic shock. METHODS: Patients with shock due to left ventricular failure complicating myocardial infarction were randomly assigned to emergency revascularization (152 patients) or initial medical stabilization (150 patients). Revascularization was accomplished by either coronary-artery bypass grafting or angioplasty. Intraaortic balloon counterpulsation was performed in 86 percent of the patients in both groups. The primary end point was mortality from all causes at 30 days. Six-month survival was a secondary end point. RESULTS: The mean age of the patients was 66+/-10 years, 32 percent were women and 55 percent were transferred from other hospitals. The median time to the onset of shock was 5.6 hours after infarction, and most infarcts were anterior in location. Ninety-seven percent of the patients assigned to revascularization underwent early coronary angiography, and 87 percent underwent revascularization; only 2.7 percent of the patients assigned to medical therapy crossed over to early revascularization without clinical indication. Overall mortality at 30 days did not differ significantly between the revascularization and medical-therapy groups (46.7 percent and 56.0 percent, respectively; difference, -9.3 percent; 95 percent confidence interval for the difference, -20.5 to 1.9 percent; P=0.11). Six-month mortality was lower in the revascularization group than in the medical-therapy group (50.3 percent vs. 63.1 percent, P=0.027). CONCLUSIONS: In patients with cardiogenic shock, emergency revascularization did not significantly reduce overall mortality at 30 days. However, after six months there was a significant survival benefit. Early revascularization should be strongly considered for patients with acute myocardial infarction complicated by cardiogenic shock.

SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK: an international randomized trial of emergency PTCA/CABG-trial design. The SHOCK Trial Study Group.

BACKGROUND: Cardiogenic shock (CS) is the leading cause of death in patients hospitalized with acute myocardial infarction (MI). Nonrandomized studies suggest reduced mortality rate with revascularization. TRIAL DESIGN: The SHOCK trial is a multicenter, randomized, and unblinded study with a Registry for trial-eligible and ineligible nonrandomized patients. The trial is testing the hypothesis that a direct invasive strategy of emergency revascularization for patients with cardiogenic shock complicating acute MI will reduce 30-day all-cause mortality rate by 20 absolute percentage points compared with initial medical stabilization. Eligibility criteria include development of CS within 36 hours of an acute transmural MI as evidenced by ST elevation or new left bundle branch block MI; clinical criteria for CS with hemodynamic confirmation; absence of a mechanical, iatrogenic, or other cause of shock; and enrollment within 12 hours of CS diagnosis. Patients randomly assigned to emergency revascularization immediately undergo coronary angiography, with percutaneous transluminal coronary angioplasty or coronary artery bypass grafting depending on the coronary anatomy. Patients assigned to initial medical stabilization may undergo revascularization >/=54 hours after randomization. END POINTS: The primary end point is all-cause 30-day mortality after randomization. Secondary end points include death at trial termination, changes in left ventricular dimensions and function measured by echocardiography at randomization and 2 weeks later, and changes in quality of life and physical functioning from 2 weeks after discharge to 6 months after MI.

Can follicle-stimulating hormone be used to define menopausal status?

OBJECTIVE: To assess the ability of the level of follicle-stimulating hormone (FSH) to distinguish among premenopausal, perimenopausal, and postmenopausal women. METHODS: We examined cross-sectional and longitudinal data from the second phase of the Massachusetts Women's Health Study (1986 to 1995), a population-based cohort of 427 premenopausal and perimenopausal women identified from the first phase of the Massachusetts Women's Health Study (1981 to 1986). RESULTS: Boxplots of FSH levels throughout the menopausal transition displayed considerable overlap. Logistic regressions and their resulting receiver operating characteristic curves further demonstrated that, although FSH is a statistically significant predictor of menopausal status, no single value of FSH is expedient for distinguishing premenopausal from perimenopausal or perimenopausal from postmenopausal women. CONCLUSION: FSH alone is not an effective predictor of transition into the perimenopausal or postmenopausal period. Specifically, the frequently recommended FSH cutoff of 40 IU/L is inappropriate by itself for clinical determination of postmenopausal status.

Psychosocial, behavioral, and health factors related to menopause symptomatology.

Despite wide variation in the reporting of hot flashes and night sweats among menopausal women, what differentiates symptomatic from asymptomatic women is not well understood. In this article, we use longitudinal data from a large cohort of initially premenopausal women to address premenopausal factors predictive of length of the perimenopause, frequency of hot flash/night sweat (HF/NS) reporting, bothersomeness of HF/NS, and treatment seeking during menopause. The sample for analysis consists of 454 women from the Massachusetts Women's Health Study who were premenopausal at baseline and postmenopausal by the sixth and last study follow-up. Each of the four study outcomes was modeled as a function of premenopausal characteristics using logistic regression. Results confirm a wide range of symptom reporting, with 23% of women not reporting HF/NS at any of the six interviews. Variables related to greater frequency of HF/NS reporting included a longer perimenopause, more psychological and physical symptoms prior to menopause, lower education, and more negative attitudes toward menopause prior to menopause. Symptom bothersomeness was related to greater frequency of HF/NS reporting, smoking, and being divorced. Variables that predicted medical doctor consultation were greater frequency and bothersomeness of symptoms, higher education, and greater health care utilization. We conclude that general symptom reporting, attitudes toward menopause, and lifestyle factors can explain some of the individual variation in symptom reporting.

Operational design and quality control in the CATCH multicenter Trial.

BACKGROUND: The Child and Adolescent Trial for Cardiovascular Health (CATCH) was the first multicenter school-based research study to employ the fundamentals of clinical trials including the standardized protocol and Manuals of Operation, a steering committee for study governance, a distributed data system, an extensive quality control system, and a Data and Safety Monitoring Board. METHOD: CATCH tested the effectiveness of changes in school lunches, physical education, smoking policy, curricula, and family activities. Ninety-six elementary schools in four states were randomized to intervention or control conditions. The baseline cohort comprised 5, 106 ethnically diverse third graders followed through fifth grade. RESULTS: The percentages of calories from fat and saturated fat were reduced significantly more in the intervention school lunches than among the controls. Significant increases in moderate to vigorous activity levels in existing physical education classes were made as well. Changes in self-reported dietary, physical activity, and psychosocial measures were significant. There were no significant differences in the physiological measures. Measurement error was generally low for all physiologic measures except skinfolds, indicating a high level of reliability. Across all sites, the coefficients of variation for lipids, height, and weight were less than 3%, whereas for skinfolds, they were considerably higher, ranging from 6 to 8%. Intraclass correlations for lipid studies were also uniformly high at 0.99. Interobserver agreement scores for SOFIT were greater than 90% for 9 of the 11 activities observed. Data entry error rates were low with less than five errors per 1,000 fields for all forms. CONCLUSIONS: The CATCH results provided more scientific evidence on the importance of schools in the population approach to health promotion. Many of the strategies used in this complex multicenter trial in the areas of design and analysis, measurement, training, data management, and quality control protocols might be appropriate for adoption in other studies.

Batch sampling to improve power in a community trial. Experience from the Pawtucket Heart Health Program.

Experiments involving large social units, such as schools, work sites, or whole cities, are commonly limited in statistical power because the number of randomized units is small, leaving few degrees of freedom for residual (between-unit) error. The authors describe a method for increasing residual degrees of freedom in a community experiment without substantially increasing cost or difficulty. In brief, they propose that the experimental units should be divided into random subsamples (batches). Batch sampling can improve statistical power if the community endpoint means are stable over time or if their temporal variation is comparable in period to the batch-sampling schedule. The authors demonstrate the theoretical advantages of the batch system and illustrate its use with data from the Pawtucket Heart Health Program, in which such a design was implemented.

Does collecting repeated blood samples from each subject improve the precision of estimated steroid hormone levels?

Measuring levels of steroid hormones in epidemiologic studies is difficult because pulsatile release can cause the levels of many hormones to vary markedly over short intervals, leading to a loss of precision in between-subject comparisons. Clinicians often control this variation by collecting several samples from each subject at defined intervals and pooling these samples for assay. The number of samples per subject that would adequately control such variation in an epidemiologic study has not been fully investigated. This study examines the effects of collecting 1, 2, or 3 samples per subject on the variances of 11 hormones and sex hormone binding globulin in men and 6 hormones in women. Three samples were collected at 30-minute intervals from each of 20 men and 59 women and were assayed separately. Variances that would be obtained in studies collecting one, two, or three samples per subject were then estimated. Collecting more than one sample substantially reduced the variances of several hormones in men but not in women.

Outcomes of a field trial to improve children's dietary patterns and physical activity. The Child and Adolescent Trial for Cardiovascular Health. CATCH collaborative group.

OBJECTIVE: To assess the outcomes of health behavior interventions, focusing on the elementary school environment, classroom curricula, and home programs, for the primary prevention of cardiovascular disease. DESIGN: A randomized, controlled field trial at four sites with 56 intervention and 40 control elementary schools. Outcomes were assessed using prerandomization measures (fall 1991) and follow-up measures (spring 1994). PARTICIPANTS: A total of 5106 initially third-grade students from ethnically diverse backgrounds in public schools located in California, Louisiana, Minnesota, and Texas. INTERVENTION: Twenty-eight schools participated in a third-grade through fifth-grade intervention including school food service modifications, enhanced physical education (PE), and classroom health curricula. Twenty-eight additional schools received these components plus family education. MAIN OUTCOME MEASURES: At the school level, two primary end points were changes in the fat content of food service lunch offerings and the amount of moderate-to-vigorous physical activity in the PE programs. At the level of the individual student, serum cholesterol change was the primary end point and was used for power calculations for the study. Individual level secondary end points included psychological factors, recall measures of eating and physical activity patterns, and other physiologic measures. RESULTS: In intervention school lunches, the percentage of energy intake from fat fell significantly more (from 38.7% to 31.9%) than in control lunches (from 38.9% to 36.2%)(P<.001). The intensity of physical activity in PE classes during the Child and Adolescent Trial for Cardiovascular Health (CATCH) intervention increased significantly in the intervention schools compared with the control schools (P<.02). Self-reported daily energy intake from fat among students in the intervention schools was significantly reduced (from 32.7% to 30.3%) compared with that among students in the control schools (from 32.6% to 32.2%)(P<.001). Intervention students reported significantly more daily vigorous activity than controls (58.6 minutes vs 46.5 minutes; P<.003). Blood pressure, body size, and cholesterol measures did not differ significantly between treatment groups. No evidence of deleterious effects of this intervention on growth or development was observed. CONCLUSION: The CATCH intervention was able to modify the fat content of school lunches, increase moderate-to-vigorous physical activity in PE, and improve eating and physical activity behaviors in children during 3 school years.

The normal menopause transition: an overview.

OBJECTIVES: This review emphasizes results from population based studies in order to provide a reliable knowledge base and define major knowledge gaps for future research. METHODS: The review systematically addresses the following aspects of menopause research: definition of menopause and menopause transitions; age at natural menopause and at inception of perimenopause; factors affecting timing and length of menopause transitions; concurrent hormone, menstrual and vascular changes. Under each substantive heading, available reports of original research are reviewed, assessed for reliability and summarized with respect to their contribution to the knowledge base. RESULTS: From this review, the following reliable information can be summarized: median age at natural menopause in Caucasian women occurs between 50 and 51-55 years of age, is not affected by timing of surgical menopause and is affected by cigarette smoking, with current smokers having an earlier menopause by 1.5-2.0 years. No other factors appear to have an independent effect on age at menopause. There is no evidence of any secular trend in age at menopause. Evidence is accumulating that most physiological change associated with menopause either occurs or begins before the final menstrual period. CONCLUSIONS: We lack reliable information on the following: estimates of age at menopause from non-industrialized countries and diverse ethnic groups; information on perimenopause; differing perceptions of menopause, cross culturally; multi-disciplinary prospective data that can link various processes into coherent patterns.

The Pawtucket Heart Health Program: community changes in cardiovascular risk factors and projected disease risk.

OBJECTIVES: Whether community-wide education changed cardiovascular risk factors and disease risk in Pawtucket, RI, relative to a comparison community was assessed. METHODS: Random-sample, cross-sectional surveys were done of people aged 18 through 64 years at baseline, during, and after education. Baseline cohorts were reexamined. Pawtucket citizens of all ages participated in multilevel education, screening, and counseling programs. RESULTS: The downward trend in smoking was slightly greater in the comparison city. Small, insignificant differences favored Pawtucket in blood cholesterol and blood pressure. In the cross-sectional surveys, body mass index increased significantly in the comparison community; a similar change was not seen in cohort surveys. Projected cardiovascular disease rates were significantly (16%) less in Pawtucket during the education program. This difference lessened to 8% posteducation. CONCLUSIONS: The hypothesis that projected cardiovascular disease risk can be altered by community-based education gains limited support from these data. Achieving cardiovascular risk reduction at the community level was feasible, but maintaining statistically significant differences between cities was not. Accelerating risk factor changes will likely require a sustained community effort with reinforcement from state, regional, and national policies and programs.

Statistical design of the Child and Adolescent Trial for Cardiovascular Health (CATCH): implications of cluster randomization.

This paper describes some statistical considerations for the Child and Adolescent Trial for Cardiovascular Health (CATCH), a large-scale community health trial sponsored by the National Heart, Lung, and Blood Institute. The trial involves randomization of entire schools rather than individual students to the experimental arms. The paper discussed the implications of this form of randomization for the design and analysis of the trial. The power calculations and analysis plan for the trial are presented in detail. The handling of outmigrating and immigrating students is also discussed.

The Massachusetts Women's Health Study: an epidemiologic investigation of the menopause.

This paper presents findings from the Massachusetts Women's Health Study (MWHS), one of the largest population-based studies of mid-aged women. A longitudinal study that followed a population-based cohort of women as they proceeded through menopause, the MWHS's goal was to describe their responses and to identify health-related, life-style, and other social factors that affect this transition. Findings indicate that natural menopause appears to have no major impact on health or health behavior. The majority of women do not seek additional help concerning menopause, and their attitudes toward it are, overwhelmingly, positive or neutral. Physicians treating mid-aged women must be careful not to confuse "menopausal" symptoms with indicators of underlying disease or conditions unrelated to menopause.

The relationship of urinary albumin excretion rate to ambulatory blood pressure and erythrocyte sodium-lithium countertransport in NIDDM.

Increased erythrocyte sodium-lithium countertransport rate is found in non-diabetic subjects with essential hypertension, and in insulin-dependent diabetic subjects with nephropathy. However, relationships between these variables in non-insulin-dependent diabetic subjects are ill-defined. In order to characterise the relationships between blood pressure, urinary albumin excretion, and erythrocyte sodium-lithium countertransport, 66 subjects with non-insulin-dependent diabetes were studied. Urinary albumin excretion rate correlated with mean 24-h ambulatory systolic blood pressure (r = 0.57; p < 0.001), but not with sodium-lithium countertransport (r = 0.06; p = 0.31). No significant relationship was observed between 24-h systolic blood pressure and erythrocyte sodium-lithium countertransport (r = 0.16; p = 0.17). The principal differences between microalbuminuric and normoalbuminuric subjects (albumin excretion rate > 15 micrograms.min-1 [n = 20], and < 15 micrograms.min-1, [n = 46]) were: higher 24-h systolic blood pressure (145.9 [16.8] mmHg vs 131.9 [16.8] mmHg; p = 0.006), nocturnal heart rate (72.4 [8.9] vs 67.4 [8.9] beats.min-1; p = 0.042), and HbA1 (11.3 [1.5]% vs 10.1 [2.0]%; p = 0.028), and a longer median duration of diabetes (10.0 vs 5.0 years; p = 0.02). In contrast, there was no significant difference in sodium-lithium countertransport rate between microalbuminuric (0.41 [0.18] mmol.l-1.h-1) and normoalbuminuric subjects (0.39 [0.15] mmol.l-1.h-1; p = 0.687).(ABSTRACT TRUNCATED AT 250 WORDS)