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Biomedical subjects

B Rosner

Publications and source records attributed to B Rosner.

At least 109 records · Page 6Linked to original sources
PubMed1994

Effectiveness and costs of veterans affairs hypertension clinics.

The effectiveness and costs of care for hypertension are examined in a stratified random sample of 3,087 patients from a network of 32 Veterans Affairs Hypertension Screening and Treatment Clinics (HSTP). During 2.5 years of follow-up, 66% and 88% of patients, respectively, had mean diastolic blood pressure (DBP) levels of 90 or 95 mm Hg or less; 73% remained fully in care; and the mean cost of ambulatory care per patient-year was $647 in 1989 dollars. Higher follow-up DBP levels were found in patients who were younger, had higher DBP levels, or were receiving medication on their first visits to a clinic, were receiving more intense treatment regimens at the beginning of the follow-up period, or had been under the care of the clinic for shorter periods. Patients who were more likely to remain in care were older, received more intense treatment regimens, had prior cardiovascular complications, or had been under the care of the clinic for a longer time. Higher annual costs were associated with higher entry DBP levels, shorter durations of care, more intense regimens, and prior cardiovascular complications. Overall, patient characteristics explained 13% of the variance in mean follow-up DBP, and 31% of variance in costs. Wide variations were found among clinics in clinical outcomes and costs. After controlling for differences in patient characteristics, clinic characteristics associated with better blood pressure control were more frequent clinic visits, shorter waiting times, more time spent in patient counseling, having therapists who had a single supervisor, and better staff satisfaction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Predictors of longitudinal change in methacholine airway responsiveness among middle-aged and older men: the Normative Aging Study.

Increasing nonspecific airway responsiveness during aging may precede and predispose to the development of asthma in later life. Characteristics potentially related to longitudinal change in methacholine airway responsiveness were examined over a 3-yr follow-up interval among 435 middle-aged and older men. Initial and follow-up evaluation included spirometry, allergy skin testing with common aeroallergens, measurement of the serum concentration of total IgE, and blood cell counts (total leukocytes and eosinophils, basophils, and neutrophils as a percentage of total leukocytes). The initial values and annual rates of change of these characteristics were examined by multiple linear regression as potential predictors of annual change in methacholine dose-response slope. Annual change in basophil count was directly related to change in dose-response slope (p = 0.02). Initial values and annual rates of change of other cell counts, pulmonary function, allergy skin test reactivity, and serum total IgE concentration were not significantly related to change in dose-response slope. Cigarette smoking history was also not significantly related to longitudinal change in dose-response slope. These data suggest that inflammatory mechanisms involving the basophil may be important in the development of increasing nonspecific airway responsiveness during aging.

Aged↗
PubMed1994

A double-blind study of cysteine photoprotection in erythropoietic protoporphyria.

In an open trial in 9 patients, we found that the ingestion of 500 mg of cysteine twice a day could prevent or lessen the photosensitivity associated with erythropoietic protoporphyria (EPP). We report here the results of a double-blind cross-over design trial in 16 patients. Patients with EPP were randomized into two groups, one that received 500 mg twice daily of cysteine during the first period and then placebo during the second period, and the second that received placebo first and then cysteine. Each drug ingestion period lasted 8 weeks, and there was a 1 week wash-out period between them. Patients were seen before the first period, at the end of the first period and at the end of the second period for phototesting, an objective method of assessing treatment efficacy, and for blood tests to monitor cysteine safety. The subjects also were asked to keep light-exposure diaries, a subjective method of assessing efficacy. We found that cysteine significantly prolonged the time it took to develop erythema by phototest, objectively demonstrating efficacy. In addition, analysis of patients' diaries showed that cysteine ingestion significantly increased the length of sun exposure it took to develop symptoms of photosensitivity. We conclude that cysteine ingestion may be an effective therapy in the prevention of photosensitivity associated with EPP.

Adolescent↗
PubMed1993

Moderate alcohol intake, increased levels of high-density lipoprotein and its subfractions, and decreased risk of myocardial infarction.

BACKGROUND: Previous studies have suggested that moderate alcohol intake exerts a protective effect against coronary heart disease. Alterations in plasma lipoprotein levels represent one plausible mechanism of this apparent protective effect. METHODS: We therefore examined the interrelation among alcohol consumption, plasma lipoprotein levels, and the risk of myocardial infarction in 340 patients who had had myocardial infarctions and an equal number of age- and sex-matched controls. The case patients were men or women less than 76 years of age with no history of coronary disease who were discharged from one of six hospitals in the Boston area with a diagnosis of a confirmed myocardial infarction. Alcohol consumption was estimated by means of a food-frequency questionnaire. RESULTS: We observed a significant inverse association between alcohol consumption and the risk of myocardial infarction (P for trend, < 0.001 after control for known coronary risk factors). In multivariate analyses, the relative risk for the highest intake category (subjects who consumed three or more drinks per day) as compared with the lowest (those who had less than one drink a month) was 0.45 (95 percent confidence interval, 0.26 to 0.80). The levels of total high-density lipoprotein cholesterol (HDL) and its HDL2 and HDL3 subfractions were strongly associated with alcohol consumption (P for trend, < 0.001 for each). The addition of HDL or either of its subfractions to the multivariate model substantially reduced the inverse association between alcohol intake and myocardial infarction, whereas the addition of the other plasma lipid measurements did not materially alter the relation. CONCLUSIONS: These data confirm the inverse association of moderate alcohol intake with the risk of myocardial infarction and support the view that the effect is mediated, in large part, by increases in both HDL2 and HDL3.

Aged↗
PubMed1993

Tubal ligation, hysterectomy, and risk of ovarian cancer. A prospective study.

OBJECTIVE: To assess whether tubal ligation and hysterectomy affect subsequent risk of ovarian cancer. DESIGN: Prospective cohort study with 12 years of follow-up. SETTING: United States, multistate. PARTICIPANTS: A total of 121,700 female registered nurses who were 30 to 55 years of age in 1976; the follow-up rate was 90% as of 1988. MAIN OUTCOME MEASURE: Ovarian cancer of epithelial origin confirmed by medical record review. RESULTS: We observed a strong inverse association between tubal ligation and ovarian cancer, which persisted after adjustment for age, oral contraceptive use, parity, and other ovarian cancer risk factors (multivariate relative risk [RR], 0.33; 95% confidence interval [CI], 0.16 to 0.64). The association was similar when we assessed tubal ligation status at the baseline questionnaire and excluded cases in the first 4 years to eliminate any possible short-term decrease in risk due to screening of the ovaries during ligation surgery. We noted a weaker inverse association between simple hysterectomy and ovarian cancer (RR, 0.67; 95% CI, 0.45 to 1.00). Neither vasectomy nor condom use by a partner was associated with risk of ovarian cancer. CONCLUSIONS: These data indicate that tubal ligation, and perhaps hysterectomy, may substantially reduce risk of epithelial ovarian cancer.

Adult↗
PubMed1993

Smoking cessation in relation to total mortality rates in women. A prospective cohort study.

OBJECTIVE: To examine the temporal relationship between stopping smoking and total mortality rates among middle-aged women. DESIGN: Prospective cohort study with 12 years of follow-up. SETTING: Registered nurses residing in the United States. PARTICIPANTS: 117,001 female registered nurses, ages 30 to 55 years, who were free of manifest coronary heart disease, stroke, and cancer (except nonmelanoma skin cancer) in 1976. MAIN OUTCOME MEASURES: Total mortality, further categorized into deaths from cardiovascular diseases, cancers, and violent deaths. RESULTS: A total of 2847 deaths (933 among "never smokers," 799 among former smokers, and 1115 among current smokers) occurred during 1.37 million person-years of follow-up. The multivariate relative risks for total mortality compared with never smokers were 1.87 (95% CI, 1.65 to 2.13) for current smokers and 1.29 (CI, 1.14 to 1.46) for former smokers. Participants who started smoking before the age of 15 years had the highest risks for total mortality (multivariate relative risk, 3.15; CI, 2.16 to 4.59), cardiovascular disease mortality (relative risk, 9.94; CI, 5.15 to 19.19), and deaths from external causes of injury (relative risk, 5.39; CI, 1.84 to 15.78). Compared with continuing smokers, former smokers had a 24% reduction in risk for cardiovascular disease mortality within 2 years of quitting. The excess risks for total mortality and both cardiovascular disease and total cancer mortality among former smokers approached the level of that for never smokers after 10 to 14 years of abstinence. The health benefits of cessation were clearly present regardless of the age at starting and daily number of cigarettes smoked. CONCLUSIONS: The risk of cigarette smoking on total mortality among former smokers decreases nearly to that of never smokers 10 to 14 years after cessation.

Adult↗
PubMed1993

Structural features of polysaccharides that induce intra-abdominal abscesses.

The capsular polysaccharide complex from Bacteroides fragilis promotes the formation of intra-abdominal abscesses--a pathologic host response to infecting microorganisms. This complex consists of two distinct polysaccharides, each with repeating units that have positively charged amino groups and negatively charged carboxyl or phosphate groups. Analysis of these polysaccharides as well as other charged carbohydrates before and after chemical modification revealed that these oppositely charged groups are required for the induction of intra-abdominal abscesses in a rat model.

Abdomen↗
PubMed1993

A prospective study of the intake of vitamins C, E, and A and the risk of breast cancer.

BACKGROUND: Although it has been hypothesized that large intakes of the antioxidant vitamins C, E, and A reduce the risk of breast cancer, few prospective data are available. METHODS: We prospectively studied 89,494 women who were 34 to 59 years old in 1980 and who did not have cancer. Their intakes of vitamins C, E, and A from foods and supplements were assessed at base line and in 1984 with the use of a validated semiquantitative food-frequency questionnaire. RESULTS: Breast cancer was diagnosed in 1439 women during eight years of follow-up. After multivariate adjustment for known risk factors, the relative risk among women in the highest quintile group for intake of vitamin C as compared with the risk among those in the lowest quintile group was 1.03 (95 percent confidence interval, 0.87 to 1.21); for vitamin E, after vitamin A intake had been controlled for, the relative risk was 0.99 (95 percent confidence interval, 0.83 to 1.19). In contrast, among women in the highest quintile group for intake of total vitamin A the relative risk was 0.84 (95 percent confidence interval, 0.71 to 0.98; P for trend = 0.001). Among women in the lowest quintile group for intake of vitamin A from food, consumption of vitamin A from supplements was associated with a reduced risk (P = 0.03). The significant inverse association of vitamin A intake with the risk of breast cancer was also found on study of data based on the 1984 questionnaire and four years of follow-up. CONCLUSIONS: Large intakes of vitamin C or E did not protect women in our study from breast cancer. A low intake of vitamin A may increase the risk of this disease; any benefit of vitamin A supplements may be limited to women with diets low in vitamin A.

Adult↗
PubMed1993

A Bayesian approach to logistic regression models having measurement error following a mixture distribution.

To estimate the parameters in a logistic regression model when the predictors are subject to random or systematic measurement error, we take a Bayesian approach and average the true logistic probability over the conditional posterior distribution of the true value of the predictor given its observed value. We allow this posterior distribution to consist of a mixture when the measurement error distribution changes form with observed exposure. We apply the method to study the risk of alcohol consumption on breast cancer using the Nurses Health Study data. We estimate measurement error from a small subsample where we compare true with reported consumption. Some of the self-reported non-drinkers truly do not drink. The resulting risk estimates differ sharply from those computed by standard logistic regression that ignores measurement error.

Age Factors↗
PubMed1993

Vitamin E consumption and the risk of coronary disease in women.

BACKGROUND: Interest in the antioxidant vitamin E as a possible protective nutrient against coronary disease has intensified with the recognition that oxidized low-density lipoprotein may be involved in atherogenesis. METHODS: In 1980, 87,245 female nurses 34 to 59 years of age who were free of diagnosed cardiovascular disease and cancer completed dietary questionnaires that assessed their consumption of a wide range of nutrients, including vitamin E. During follow-up of up to eight years (679,485 person-years) that was 97 percent complete, we documented 552 cases of major coronary disease (437 nonfatal myocardial infarctions and 115 deaths due to coronary disease). RESULTS: As compared with women in the lowest fifth of the cohort with respect to vitamin E intake, those in the top fifth had a relative risk of major coronary disease of 0.66 (95 percent confidence interval, 0.50 to 0.87) after adjustment for age and smoking. Further adjustment for a variety of other coronary risk factors and nutrients, including other antioxidants, had little effect on the results. Most of the variability in intake and reduction in risk was attributable to vitamin E consumed as supplements. Women who took vitamin E supplements for short periods had little apparent benefit, but those who took them for more than two years had a relative risk of major coronary disease of 0.59 (95 percent confidence interval, 0.38 to 0.91) after adjustment for age, smoking status, risk factors for coronary disease, and use of other antioxidant nutrients (including multi-vitamins). CONCLUSIONS: Although these prospective data do not prove a cause-and-effect relation, they suggest that among middle-aged women the use of vitamin E supplements is associated with a reduced risk of coronary heart disease. Randomized trials of vitamin E in the primary and secondary prevention of coronary disease are being conducted; public policy recommendations about the widespread use of vitamin E should await the results of these trials.

Adult↗
PubMed1993

Relation of smoking and low-to-moderate alcohol consumption to change in cognitive function: a longitudinal study in a defined community of older persons.

To determine whether smoking habits and alcohol consumption are related to changes in cognitive function, the authors conducted a prospective, community-based study of persons aged 65 years and over in East Boston, Massachusetts. In 1982 and again in 1985, the subjects were given three brief tests of cognitive function: immediate memory, digit span, and a mental status questionnaire, which primarily assessed orientation. The 1,201 individuals who performed well in 1982 were included in linear regression analyses of 3-year change in performance, adjusted for age, sex, education, and income. Relative to nonsmoking, current smoking, past smoking, and pack-years were not significantly related to change in immediate memory. None was significantly related to change in orientation. Only pack-years was significantly related to normal change score in digit span (normal change score change per unit of predictor = 0.001, 95% confidence interval 0.0003-0.002). Low-to-moderate alcohol consumption during the month preceding baseline testing was not significantly related to a subsequent 3-year change in performance in two of the three tests. However, people who consumed a very small amount of alcohol had a normal change score that was 0.088 (95% confidence interval 0.015-0.160) better for digit span than did nondrinkers. This study provides evidence that the reported levels of smoking and alcohol use among older persons are not consistent or substantial predictors of the longitudinal change in cognitive function observed in a community.

Aged↗
PubMed1993

Natural history of coronary atherosclerosis using quantitative angiography in men, and implications for clinical trials of coronary regression. The Harvard Atherosclerosis Reversibility Project Study Group.

Previous studies of the natural history of coronary disease generally relied on estimates of percent stenosis derived from visual assessment of the coronary angiogram. In a study of 26 patients, serial quantitative angiography was performed 3 years apart to determine changes in both absolute measurements of the luminal diameter and relative percent stenosis. Initially, the mean minimal diameter of 74 coronary obstructions was 1.94 +/- 0.09 mm, the mean "normal" reference diameter was 3.06 +/- 0.11 mm, and the mean percent stenosis was 37%. At follow-up, there was a mild reduction of 0.12 +/- 0.04 mm (6%) in the minimal diameter (p < 0.005), and an increase in percent stenosis to 39% (p = 0.03). The average diameter of 85 arterial segments without a focal obstruction either initially or at follow-up showed mild but significant progression (-0.11 +/- 0.04 mm; p = 0.02). Using a minimal change of 0.27 mm in arterial diameter as a categoric variable, progression occurred in 26% of 74 arterial segments, no significant change in 65%, and regression in 9%. The only significant determinant of disease progression was the initial severity of disease. Obstructed arteries with a larger initial minimal diameter and presumably milder disease progressed more rapidly than did those with a smaller diameter (r = -0.42; p = 0.0002). There was no effect of age on the rate of progression (r = 0.02; p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Catheterization↗
PubMed1993

Smoking cessation and decreased risk of stroke in women.

OBJECTIVE: To prospectively examine the relationship of time since stopping smoking with risk of stroke in middle-aged women. DESIGN: An ongoing prospective cohort of women with 12 years' follow-up data (1976 to 1988), in which information on smoking habits was updated every 2 years by postal questionnaire. POPULATION STUDIED: A total of 117,006 female registered nurses aged 30 to 55 years in 1976 and free of coronary heart disease, stroke, and cancer at baseline. MAIN OUTCOME MEASURES: Incident strokes (fatal and nonfatal), further subdivided into ischemic stroke, subarachnoid hemorrhage, and cerebral hemorrhage. RESULTS: The age-adjusted relative risk of total stroke among current smokers compared with never smokers was 2.58 (95% confidence interval, 2.08 to 3.19). The corresponding relative risk among former smokers was 1.34 (95% confidence interval, 1.04 to 1.73). For total and ischemic stroke, the excess risks among former smokers largely disappeared from 2 to 4 years after cessation. The same patterns of decline were observed regardless of number of cigarettes smoked, the age at starting, or the presence of other risk factors for stroke. CONCLUSIONS: The risk of suffering among cigarette smokers declines soon after cessation and the benefits are independent of the age at starting and the number of cigarettes smoked per day.

Adult↗
PubMed1993

A prospective study of aspirin use and cataract extraction in women.

We examined the association between aspirin use and the rates of cataract extraction during 8 years of follow-up in a large prospective study of women, the Nurses' Health Study. From 1980 to 1988, we documented 448 senile cataracts diagnosed and extracted during 434,680 person-years of follow-up. While we observed a modest positive association at the higher doses of aspirin use in the age-adjusted analyses, no association was found after accounting for other cataract risk factors (relative risk for > or = 20 years of use, 1.08; 95% confidence interval, 0.84 to 1.39). Among women who consumed seven or more tablets per week for 20 or more years, there was no suggestion of protection; if anything, a nonsignificantly elevated risk was observed (relative risk, 1.31; 95% confidence interval, 0.94 to 1.80). We observed no consistent difference in the relationship between aspirin use and cataract when assessed by age. Overall, we found no evidence to support the substantial reduction in risk of cataract among aspirin users as reported in several previous studies.

Age Factors↗
PubMed1993

A randomized trial of vitamin A and vitamin E supplementation for retinitis pigmentosa.

OBJECTIVE: To determine whether supplements of vitamin A or vitamin E alone or in combination affect the course of retinitis pigmentosa. DESIGN: Randomized, controlled, double-masked trial with 2 x 2 factorial design and duration of 4 to 6 years. Electroretinograms, visual field area, and visual acuity were measured annually. SETTING: Clinical research facility. PATIENTS: 601 patients aged 18 through 49 years with retinitis pigmentosa meeting preset eligibility criteria. Ninety-five percent of the patients completed the study. There were no adverse reactions. INTERVENTION: Patients were assigned to one of four treatment groups receiving 15,000 IU/d of vitamin A, 15,000 IU/d of vitamin A plus 400 IU/d of vitamin E, trace amounts of both vitamins, or 400 IU/d of vitamin E. MAIN OUTCOME MEASURE: Cone electroretinogram amplitude. RESULTS: The two groups receiving 15,000 IU/d of vitamin A had on average a slower rate of decline of retinal function than the two groups not receiving this dosage (P = .01). Among 354 patients with higher initial amplitudes, the two groups receiving 15,000 IU/d of vitamin A were 32% less likely to have a decline in amplitude of 50% or more from baseline in a given year than those not receiving this dosage (P = .01), while the two groups receiving 400 IU/d of vitamin E were 42% more likely to have a decline in amplitude of 50% or more from baseline than those not receiving this dosage (P = .03). While not statistically significant, similar trends were observed for rates of decline of visual field area. Visual acuity declined about 1 letter per year in all groups. CONCLUSIONS: These results support a beneficial effect of 15,000 IU/d of vitamin A and suggest an adverse effect of 400 IU/d of vitamin E on the course of retinitis pigmentosa.

Adolescent↗