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S Wassertheil-Smoller

Publications and source records attributed to S Wassertheil-Smoller.

At least 55 records · Page 3Linked to original sources
PubMed1988

The clinical use of nuclear exercise tests.

In the mid-1970s, after decades of clinical use, the utility of electrocardiographic exercise testing for the evaluation of patients with suspected ischemic heart disease was critically examined and questioned. Concurrent with this critique, two sophisticated, more expensive and powerful "nuclear" exercise tests were introduced sequentially for clinical use: myocardial perfusion imaging with thallium-201 and radionuclide ventriculography with technetium 99m. The published indications for the two tests are similar, and both have been shown to offer advantages over ECG stress testing in selected populations. However, few data are available regarding the comparative utility of thallium versus ventriculographic imaging. As part of a prospective study to assess the efficacy of cardiovascular nuclear medicine studies, we undertook the present analysis to assess the clinical evolution of these tests and to elucidate factors responsible for clinicians' choice for the often competing examinations. The study examined 213 consecutive patient referrals for thallium scintigraphy and 183 referrals for ventriculography, ranging from patients with no symptoms or highly non-specific chest pain syndromes (21% of referrals) to patients with proven coronary disease (28% of the referrals). Twenty-one percent of patients were referred to confirm the clinical impression that the patient did not have coronary disease, 40% to confirm its presence, and 37% to determine its severity. Analyses were undertaken to determine the factors that dictated a preference for thallium scintigraphy rather than ventriculography; only the physician's intent in testing and level of training were significant predictors for a particular nuclear test.

Coronary Disease↗
PubMed1988

The relationship between left ventricular systolic function and congestive heart failure diagnosed by clinical criteria.

There is no uniformly accepted clinical definition for congestive heart failure (CHF), although criteria have been published by various groups. There is also no reference standard for CHF, although left ventricular ejection fraction (LVEF) gives a quantitative assessment of systolic function and is useful in predicting prognosis. To determine the relationship between LVEF and clinically diagnosed CHF, we compared resting LVEF determined by radionuclide ventriculography with diagnosis of CHF by clinical criteria in 407 patients, based on clinical data collected by a cardiology fellow. Of 153 patients with a low LVEF (less than or equal to 0.40), 30 (20%) met none of the criteria for CHF. Conversely, of 204 patients with normal LVEF (greater than or equal to 0.50), 105 (51%) met at least one of the criteria. We conclude that different criteria for CHF will have varying utility depending on the population being examined, and that a combination of clinical features and an objective measure of cardiac performance is needed to diagnose CHF.

Female↗
PubMed1988

Clinical experience with COP-1 in multiple sclerosis.

COP-1 is one of a series of polypeptide preparations developed to stimulate myelin basic protein (MBP), a natural component of the myelin sheath. MBP in Freund's complete adjuvant induces experimental allergic encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). In saline, MBP suppresses EAE. This is the rationale for the use of COP-1 in MS.

Adult↗
PubMed1987

A pilot trial of Cop 1 in exacerbating-remitting multiple sclerosis.

Cop 1 is a random polymer (molecular weight, 14,000 to 23,000) simulating myelin basic protein. It is synthesized by polymerizing L-alanine, L-glutamic acid, L-lysine, and L-tyrosine. It suppresses but does not induce experimental allergic encephalomyelitis, an animal model of multiple sclerosis. It is not toxic in animals. In a double-blind, randomized, placebo-controlled pilot trial, we studied 50 patients with the exacerbating-remitting form of multiple sclerosis, who self-injected either 20 mg of Cop 1 dissolved in 1 ml of saline or saline alone daily for two years. Six of 23 patients in the placebo group (26 percent) and 14 of 25 patients in the Cop 1 group (56 percent) had no exacerbations (P = 0.045). There were 62 exacerbations in the placebo group and 16 in the Cop 1 group, yielding two-year averages of 2.7 and 0.6 per patient, respectively. Among patients who were less disabled on entry (Kurtzke disability score, 0 to 2), there were 2.7 exacerbations in the placebo group and 0.3 in the Cop 1 group over two years. Among patients who were more affected (Kurtzke disability score, 3 to 6), there was an average of 2.7 exacerbations in the placebo group and 1.0 in the Cop 1 group. Over two years, less disabled patients taking Cop 1 improved an average of 0.5 Kurtzke units; those taking placebo worsened an average of 1.2 Kurtzke units. More disabled patients worsened by 0.3 (Cop 1 group) and 0.4 (placebo group) unit. Irritation at injection sites and rare, transient vasomotor responses were observed as side effects. These results suggest that Cop 1 may be beneficial in patients with the exacerbating-remitting form of multiple sclerosis, but we emphasize that the study is a preliminary one and our data require confirmation by a more extensive clinical trial.

Adult↗
PubMed1987

Nuclear scans: a clinical decision making tool that reduces the need for cardiac catheterization.

We have assessed the impact of cardiovascular nuclear medicine studies (CVNMS) on physicians' decisions to send patients with suspected ischemic heart disease (N = 439) on to cardiac catheterization at three Bronx hospitals. A change in management plans with respect to catheterization was observed in 31% of cases. Catheterization rates were reduced by 25% among patients referred for resting studies and by 49% for exercise studies (thallium perfusion or exercise wall motion studies). Results of CVNMS had little impact on catheterization decisions for resting study patients (N = 192). Among exercise study patients (N = 247), those with normal results had a relative reduction in catheterization post-CVNMS of 82% vs 27% for patients with abnormal results (p less than 0.001). However, impact of exercise CVNMS test results on post-CVNMS catheterization rates obtained for men only; women with abnormal exercise study results were much less likely to undergo subsequent catheterization (7.7%) than men with abnormal results (41.9%), p less than 0.005, independent of age. The apparent discrepancy in referral for catheterization based on sex needs to be investigated further.

Adolescent↗
PubMed1987

Sex bias in considering coronary bypass surgery.

Cardiovascular nuclear medicine exercise studies may serve as a screening method to be used in making decisions to refer patients for catheterization and coronary artery bypass surgery. In a study of 390 patients consecutively referred for nuclear exercise testing, abnormal results found in 31% of the women and in 64% of the men affected physicians' decisions to recommend catheterization in men only; 4% of the women with abnormal radionuclide scans were referred for catheterization compared with 40% of the men (p less than 0.001). this 10:1 ratio was independent of age. A multiple logistic regression analysis that controlled for age, previous myocardial infarction, presence of typical and atypical angina, and abnormal test results yielded an odds ratio of 6.3 for men. The male-to-female ratio of patients with coronary artery disease given abnormal results of a cardiovascular nuclear scan is only 2:1. Thus, the sex differential in decisions to refer patients for cardiac catheterization cannot be explained entirely by differences in the sensitivity of tests or the rates of coronary artery disease; it also cannot be explained by differential benefits from surgery. These findings raise the question of whether coronary artery bypass surgery is underused in women.

Aged↗
PubMed1986

Prediction of response to sodium intervention for blood pressure control.

In the Dietary Intervention Study of Hypertension (DISH) we found that patients formerly treated with drugs and assigned to sodium-reduction intervention were twice as likely to remain off medication for up to 56 weeks as were the controls assigned to no-diet intervention, after adjusting for covariates. Within the sodium-restriction group approximately 60% of 131 people were Intervention Successes (IS) (urinary sodium less than or equal to 100 mmol/day at 8 weeks). The rest were classed as Non-Intervention Successes (NIS). Of the IS group, 54% were responders (drug-free for at least 56 weeks), but about 56% of the NIS group also remained drug-free. Multiple logistics showed that no one factor was able to predict response among the IS. We conclude that the IS likely to respond to sodium reduction are not readily identifiable a priori. Furthermore, since both IS and NIS showed similar blood-pressure effects from the sodium-restriction regimen compared with controls, the questions arise: whether a factor other than sodium reduction affects the blood pressure response for the sodium-restriction group; or whether the measurement of sodium intake and excretion is sufficiently precise to distinguish compliers from non-compliers.

Antihypertensive Agents↗
PubMed1985

Plasma vitamin C and uterine cervical dysplasia.

Plasma concentrations of vitamin C were determined in a case-control study of women (n = 80) who had sought a Papanicolaou test in the Bronx Municipal Hospital Center. Controls (n = 34) were women having negative cytologic tests, negative colposcopic findings, and no known gynecologic dysfunction. Cases (n = 46) were defined as women who had either one positive or two consecutive suspicious Papanicolaou smears in a 12-month period. The mean concentration of vitamin C in the plasma was significantly lower in the cases than in the controls (0.36 versus 0.75 mg/dl, p less than 0.0001). Cases were further stratified according to the histopathologic diagnosis. The data direct attention to a possible etiologic association of vitamin C in human cervical epithelial abnormalities. A clinical trial with vitamin C intervention is suggested.

Adult↗
PubMed1985

Dietary therapy slows the return of hypertension after stopping prolonged medication.

This study asks whether prolonged antihypertensive therapy will "cure" a substantial percent of rigorously treated hypertensive patients and whether nutritional change will add an antihypertensive effect and reduce the relapse rate. Of 584 eligible patients normotensive while receiving therapy, 496 were randomized into control and discontinued-medication groups with and without dietary intervention. At 56 weeks, 50% of those who were no longer receiving medication remained normotensive by study criteria. Randomization either to weight-loss group (mean loss of 4.5 kg [10 lb]) or to sodium-restriction group (mean reduction of 40 mEq/day) increased the likelihood of remaining without drug therapy, with an adjusted odds ratio of 2.17 for the sodium group and 3.43 for the weight group. Highest success rates were in the nonoverweight mild hypertensives with sodium restriction (78%) and the overweight mild hypertensives who were reducing their weight (72%). These data demonstrate that weight loss or sodium restriction, in hypertensives controlled for five years, more than doubles success in withdrawal of drug therapy.

Clinical Trials as Topic↗
PubMed1985

Effective dietary intervention in hypertensives: sodium restriction and weight reduction.

A Dietary Intervention Study of Hypertension (DISH) was undertaken to determine whether patients whose high blood pressure had been controlled pharmacologically for a period of more than 5 years could maintain that control with sodium restriction or weight reduction instead of drugs. Four hundred ninety-six patients, classified by degree of overweight, were randomly assigned into one of seven groups. Included were those who would be withdrawn from antihypertensive medication and receive intervention for either sodium restriction or weight reduction. After 8 weeks of intervention, an average reduction of 24-hour urinary sodium output from a baseline of 158 mEq to 106 mEq (p less than .001) and from 130 mEq to 96 mEq (p less than .01) was achieved for the overweight and nonoverweight groups, respectively. That decline was still maintained at 56 weeks. Dietary estimates, obtained by analysis of 3-day food records, underestimated urinary output by an average of 12%, with blacks more likely to underestimate than whites, and the overweight more likely to underestimate than the nonoverweight. An average 10-lb weight loss was achieved, with no difference between men and women. Weight declined for 32 weeks, then leveled off and was maintained up to 56 weeks, indicating that sodium intake modification can be accomplished faster than weight reduction. Modest sodium restriction and weight reduction are feasible and achievable in a free-living population and have a positive effect on control of hypertension.

Clinical Trials as Topic↗
PubMed1984

Influence of vitamin A on cervical dysplasia and carcinoma in situ.

A case-control study was undertaken to determine the dietary intake of vitamin A in women having abnormal uterocervical cytology. The study groups (87 cases and 82 controls) were drawn from a population of women who received a screening Pap test in the ambulatory health care section of a large municipal hospital center. A subset of cases (with abnormal cytology) were matched to controls for age, ethnicity, socioeconomic status, and parity. Nutrient intake and retinol binding protein concentrations were determined; epidemiological data were also obtained. It was found that the subset of cases with severe dysplasia or carcinoma in situ (CIS) were more likely to have a total dietary vitamin A intake below the pooled median (3,450 IU) and/or a beta-carotene intake below the pooled median (2,072 IU) than were normal controls (p less than 0.05 and p less than 0.025, respectively). Odds ratios revealed approximately a 3-fold greater risk for severe dysplasia or CIS in women with lowered vitamin A or beta-carotene intake. In addition, retinol binding protein was either absent or undetectable in 78.8% of the dysplastic tissue samples, versus 23.5% of the normal tissue samples (p less than 0.005).

Adolescent↗
PubMed1984

Return of hypertension after withdrawal of prolonged antihypertensive therapy, effect of weight loss, sodium reduction, and baseline factors.

The effect of dietary modification on continued blood pressure control after discontinuation of antihypertensive therapy has been studied. Participants who had been treated for 5 years in the Hypertension Detection and Follow-up Program were enrolled and randomly assigned to continue medication, discontinue medication with no dietary intervention, discontinue medication and reduce weight, discontinue medication and reduce sodium groups. Relapse of hypertension was slow, even without dietary modification. Both weight loss and sodium restriction slowed relapse. The severity of the hypertension and the number of drugs required for hypertension control had a marked effect on the rate of relapse. Relapse was slowest in the participants who had attained the lowest blood pressure on therapy.

Adult↗
PubMed1981

Retinoids and the prevention of cervical dysplasias.

Women with abnormal cytology were matched with normal control subjects for age, parity, ethnicity, and socioeconomic class and participated in a blind case-control study focused on the role of nutrition in cervical dysplasia. Sucrose gradient ultracentrifugation studies for determination of the presence and concentration of the binding proteins for retinol and retinoic acid were performed on colposcopic biopsy tissue specimens. The nutritional survey revealed statistically significant differences for vitamins A and C and beta carotene. Retinol binding protein was absent or minimally detectable and inversely related to the severity of the dysplasia. It is proposed that a double-blind clinical trial be conducted to evaluate whether retinoids may pharmacologically inhibit, arrest, or reverse cervical dysplasia.

Ascorbic Acid↗
PubMed1981

Dietary vitamin C and uterine cervical dysplasia.

A case-control study of women with cervical abnormalities identified through Pap smears, was conducted in the Bronx, New York, to explore the relationship between nutritional intake and cervical dysplasia. Nutrient intake was estimated from computer analysis of three-day food records and 24-hour recall for 169 study participants (87 cases, 82 controls), including a subset of 49 pairs matched for age, race and parity. Mean vitamin C intake per day from three-day food record for controls was 107 mg, compared to 80 mg for cases (p less than 0.01). Analysis of matched pairs showed similar results; 29% of cases compared to 3% of controls in matched subset had vitamin C intake less than 50% of the recommended daily allowance, yielding a ten-fold increase in risk of cervical dysplasia as estimated by odds ratio (p less than 0.05). Younger age, greater frequency of sexual intercourse and younger age at first intercourse were associated with higher risk of cervical dysplasia. Multiple logistic analyses indicated that low vitamin C intake is an independent contributor to risk of severe cervical dysplasia when age and sexual activity variables are controlled. Approximately 35% of US women in their reproductive years have daily vitamin C intake below 30 mg, and 68% have vitamin C intake below 88 mg. If other studies confirm these findings, it may be important to explore a possible protective role of supplementary vitamin C for women at high risk of cervical cancer.

Adolescent↗
PubMed1981

High blood pressure diagnosis and treatment: consensus recommendations vs actual practice.

Diagnostic and treatment practices of institutional facilities treating high blood pressure in New York City were surveyed by mail in 1978. Respondents were adhering to the treatment recommendations of the Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure. Ninety-two per cent of respondents reported 90-104 mm Hg as the diastolic blood pressure level at which drug therapy was initiated, indicating a more aggressive approach than was warranted by the information available at the time of the survey.

Adult↗