PubMed HealthSearch

Biomedical subjects

H Bryant

Publications and source records attributed to H Bryant.

At least 19 recordsLinked to original sources

The review of randomization in the Canadian National Breast Screening Study. What does the verdict mean for clinicians?

What is the practising clinician to make of the review by Drs. John C. Bailar III and Brian MacMahon (see pages 193 to 199 of this issue) of the randomization procedure used in the Canadian National Breast Screening Study? Their conclusion that any flaws in randomization would not have affected the published data is reassuring. Nevertheless, the review has not resolved the controversy surrounding the recommendations for screening mammography for women aged 40-49. Recommendations must be based on strong evidence that the benefits of population-based testing outweigh the harms. The absence of such evidence for women aged 40-49 should not, however, preclude the use of mammography as a diagnostic test for women in their 40s whose clinical signs require follow-up. Mammography could also be considered for women whose family history or other factors suggest an increased risk for breast cancer, provided that the limitations and potential disadvantages of testing are explained.

Adult

How should we interpret noncompliance with screening mammography?

Primary care practitioners have an important role to play in recommending breast cancer screening to patients in the target age group. In this issue of CMAJ (see pages 1335 to 1343) Dr. Marie-Dominique Beaulieu and associates report the results of a program designed to maximize utilization of screening mammography. Only two thirds of eligible women for whom screening mammography was prescribed obtained a mammogram within the 2-month study period. However, when taken in context, this compliance rate is fairly encouraging. There are many possible reasons for noncompliance such as a need for more information or for repeated suggestions. Family physicians should not become disheartened in their efforts to increase the use of screening procedures and may find that collaboration with others in giving consistent messages will help to maximize screening rates within their patient population.

Female

A Canadian experiment with breast cancer information exchange pilot projects.

Responding to concerns articulated by Canadian women living with breast cancer and their families, the federal government has provided $2.7 million over five years to establish five regional information exchange pilot projects. Women experience considerable variation in access to information reflecting different resources, communication links and health care delivery systems in each province or territory. The five information projects are taking different approaches to enhance coordination of existing resources and involve women living with breast cancer to improve access to credible, timely, breast cancer information.

Breast Neoplasms

Breast implants and breast cancer--reanalysis of a linkage study.

BACKGROUND: In 1992, Berkel and colleagues reported in the Journal the results of their study of the potential association of breast augmentation and breast cancer. The study reported that women who had breast augmentation had a significantly lower subsequent risk of breast cancer (P < 0.01) than the general population, with a standardized incidence ratio of 0.48 overall. Assuming a 10-year induction period (that is, assuming that cancers found within 10 years of the augmentation might have been the result of a process begun before surgery and therefore should not be considered), the reported standardized incidence ratio was 0.16. Problems were later identified involving some of the study methods. This paper reports a second analysis of these data. METHODS: We used a data set from Alberta Health Care to identify eligible women with bilateral breast augmentation. Using a combination of deterministic and probabilistic methods, we linked this data set to the Alberta Cancer Registry to identify subsequent breast cancers that developed during the study period. Multiple estimates of standardized incidence ratios were calculated on the basis of differing study-eligibility dates, induction periods, and types of breast-cancer (invasive only or invasive plus in situ). RESULTS: The reanalysis found substantial differences in the numbers of person-years at risk, resulting in higher standardized incidence ratios than in the original analysis. The final ratios for all breast cancers, with October 1, 1973, used as the starting date of the study, were 0.76 (95 percent confidence interval, 0.55 to 1.02), 0.85 (95 percent confidence interval, 0.58 to 1.19), and 0.68 (95 percent confidence interval, 0.32 to 1.25) for induction periods of 0, 5, and 10 years, respectively. None of these standardized incidence ratios were significantly different from 1. CONCLUSIONS: On the basis of this reanalysis, the incidence of breast cancer among the women who had breast augmentation could not be said to be either significantly higher or lower than that among the general population over the period during which this cohort was followed.

Adult

Teaching medical students how to perform a clinical breast examination.

BACKGROUND: One challenge in medical education is to provide training in physical examination skills. The authors conducted a randomized study to compare standardized and unstandardized methods of teaching clinical breast examinations and to determine whether trained non-medical women could teach as well as medical faculty. METHOD: Sensitivity, specificity, and examination techniques were compared between first-year students at the University of Calgary Faculty of Medicine who in 1992-93 received standardized teaching from family medicine faculty or well women teachers and 70 second-year students who received unstandardized teaching during their clinical rotations. Standardized teaching included a specific examination technique using silicone breast models. The students taught by the well women teachers also examined the women's breasts. RESULTS: The standardized-teaching group had more consistent examination techniques and significantly higher sensitivity but lower specificity. The students taught by the well women teachers performed as well as those taught by the family medicine faculty. CONCLUSIONS: The teaching methods used by trained teachers and standardized models improved the students'accuracy of breast lump detection and examination skills.

Breast Diseases

Age as a factor in breast cancer knowledge, attitudes and screening behaviour.

OBJECTIVE: To determine whether there are age-related differences in knowledge, attitudes and behaviour with respect to breast cancer and whether the differences reflect the age-specific Canadian recommendations on breast cancer screening. DESIGN: Telephone survey. SETTING: Two cities and five towns and their surrounding areas in Alberta. PARTICIPANTS: The age-specific, randomly selected sample comprised 1284 women aged 40 to 75 years who did not have breast cancer. Of the 1741 eligible women who were contacted, 1350 (78%) agreed to participate; 66 were excluded because of age ineligibility or a history of breast cancer. MAIN OUTCOME MEASURE: Frequency of knowledge, attitudes and behaviour with respect to breast cancer, by age group. RESULTS: Knowledge of breast cancer risk factors was generally low and decreased with age. Few women were aware of the Canadian recommendations on breast self-examination, physical examination of the breasts by a health care practitioner and mammographic screening. Older women believed they were less susceptible to breast cancer than younger women and were less likely to have positive attitudes toward screening. Self-examination was performed 9 to 15 times per year by 424 women (33%), and 810 (63%) had been examined by a health care professional in the past year. Although 664 (52%) had undergone mammography, the proportion decreased with age after age 59. The main barriers to mammography were lack of physician referral and the woman's belief that the procedure is unnecessary if she is healthy. CONCLUSIONS: Education is needed to increase breast cancer knowledge, promote the Canadian recommendations for early detection of breast cancer and decrease negative beliefs about the disease. Changes in the behaviour of women and physicians are needed to increase the use of breast self-examination, clinical breast examination by a health care professional and mammographic screening. Reaching women in the upper range (60 to 69 years) of the target group for mammographic screening should be a focus in promoting early detection of breast cancer.

Adult

Effect of oral contraceptive use on reoperation following surgery for Crohn's disease.

The influence of oral contraceptive (OCP) use as a risk factor for the development of Crohn's disease is disputed. We wished to determine if OCP use affected the risk of recurrence (defined as need for a second surgery) in women who had already undergone a resection for Crohn's disease. We hypothesized that if contraceptive use was a risk factor for disease development, it could influence recurrence. Using a mail questionnaire, we surveyed 138 women regarding their OCP use following surgery for Crohn's disease. All participants were between ages 16 and 35 at the time of their initial surgery which occurred between 1966 and 1984. Ninety-seven women (70%) responded. Mean follow-up was 9.9 years (range 4-27). Forty-six women required a second surgery. The recurrence rate as determined by actuarial analysis, was 27.2% (95% confidence intervals (CI95 16.5-38.1) and 58.0% (CI95 37.8-78.2) at 5 and 10 years, respectively. Thirty-two women took OCP in the first year following surgery. Eleven OCP users (34.4%) required additional surgery compared to 34 (53.1%) of nonusers. Using life table analysis, the percentage requiring a second surgery was 25.0% (CI95 6.9-43.1) and 40.7% (CI95 1.5-80%) at 5 and 10 years, respectively, for users compared to 28.4% (CI95 6.9-43.1) and 64.0% (CI95 40.5-87.5) for nonusers (Lee Desu, P greater than 0.05). When surveyed about their reasons for using OCP, most women stated that their disease did not affect their decision to use contraceptives.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Breast cancer screening attitudes and behaviors of rural and urban women.

This study was carried out to assess the breast cancer knowledge, attitudes, and awareness of women age 40 to 74 in Alberta, a Canadian province of 2.4 million people. This analysis compares the attributes of 538 rural women, defined as those living between 1 and 3 hr drive from the major cities in Alberta, and 735 urban women who lived in one of these two cities. Rural women were found to have the same basic knowledge of breast cancer or perceptions of barriers to mammography, but had more negative attitudes about breast cancer itself. Despite their similar access to physician care, they were less likely to have had a recent clinical breast examination or mammogram (P less than 0.001). These differences remained when adjustment was made for demographic background variables; the adjusted prevalence rate ratio for a screening mammogram in the past 2 years was 0.52 (95% C.I., 0.43, 0.64), and for intention to have a mammogram in the next 2 years, 0.75 (0.63, 0.90). The results suggest particular program delivery strategies when planning for provision of breast screening information and service to the large subgroup of rural women.

Adult

Prolactin and prolactin secretagogues reverse immunosuppression in mice treated with cysteamine, glucocorticoids, or cyclosporin-A.

Suppression of prolactin (PRL) secretion with the dopamine agonist, bromocriptine, has been shown in rodents to diminish a variety of immunologic responses, including delayed type hypersensitivity, primary antibody response, T-cell dependent macrophage activation, and ex vivo T- and B-lymphocyte proliferation in response to mitogens. These same responses can be suppressed by endogenous or exogenous glucocorticosteroids and, in large measure, the immunosuppressant peptide cyclosporin A. The sulfhydryl reducing agent cysteamine (2-aminoethanethiol) is known to reduce pituitary and plasma prolactin levels. Treatment of mice with cysteamine at doses which suppressed circulating PRL levels resulted in suppression of ex vivo blastogenic responses of lymphocytes from treated mice. The T-cell-dependent primary IgM response to immunization with sheep red blood cells was also suppressed by cysteamine treatment. Treatment of mice with drugs stimulating the release of endogenous PRL, or with exogenous ovine PRL, was found to antagonize the suppression of lymphocyte proliferative responses to mitogens induced in mice by glucocorticoid or cyclosporin treatment. These data suggest that many drugs in common clinical use could have potential immunomodulatory actions due to suppression or stimulation of pituitary PRL secretion. Furthermore, lactogenic hormones appear to exert counterregulatory actions which may modify glucocorticosteroid actions on immune and other target issues.

Adrenocorticotropic Hormone

Restoration of juvenile baseline growth hormone secretion with preservation of the ultradian growth hormone rhythm by continuous delivery of growth hormone-releasing factor.

The ability of continuously delivered GH-releasing factor (GRF) to enhance GH secretion while maintaining the normal ultradian GH rhythm was investigated. Synthetic human GH-releasing factor (hGRF(1-44)NH2) was continuously infused for 4 days by means of i.v. catheters to 11-week-old broiler chickens. At this age, overall endogenous GH secretion is low, and baseline GH is barely detectable. Six birds per treatment received vehicle (control), 0.324 mg hGRF(1-44)NH2/kg body weight per day (low dose) or 3.24 mg hGRF(1-44)NH2/kg body weight per day (high dose). After 4 days of GRF conditioning, concurrent with continued GRF infusion, serial blood samples were removed via atrial catheters at 15-min intervals for 6 h and GH plasma profiles determined. High dose GRF significantly increased GH plasma concentrations over tenfold compared with controls; however, most of this increase reflected an increase in basal GH, which was reinstated to juvenile baseline levels. Augmentation of pulse amplitude above this increased baseline was not proportionately as high, and failed to reach juvenile levels. The ultradian rhythm of GH was not altered by continuous GRF administration. Both low and high dose GRF treatments resulted in significant enlargement of the anterior pituitary gland. Total pituitary GH mRNA levels, although elevated over twofold by GRF treatment, were not significantly different from controls. Measures of plasma GH magnitude (overall and baseline mean, and peak amplitude) were significantly correlated with pituitary GH mRNA for control birds, but were not correlated for GRF treatments. Feed intake was markedly depressed (33%) on the high dose GRF treatment, in conjunction with total inhibition of body weight gain over the 4-day period of administration. Longitudinal bone growth and width of the epiphyseal growth plate were also significantly reduced by high dose GRF treatment, probably reflecting the reduced level of nutrient intake, despite high circulating concentrations of GH.

Animals

Effect of cigarette smoking on recurrence of Crohn's disease.

The effect of cigarette smoking on recurrence (defined in this study as the need for repeat surgery) in patients who had previously required surgery for Crohn's disease was assessed in a historical cohort of 174 patients. Mean follow-up was 10.8 yr. The 5- and 10-yr recurrence rates were 28% and 56%, respectively. Five- and 10-yr rates were significantly different for smokers (36%, 70%) and nonsmokers (20%, 41%). When patients were stratified by gender, the increased risk was more apparent in women (odds ratio 4.2, 95% confidence interval 2.0-4.2) than in men (odds ratio 1.5, 95% confidence interval 0.8-6.0). Evidence for a dose-response relationship could be identified in women but not men. Cigarette smoking may not only be a risk factor for development of Crohn's disease but also may influence disease activity following surgery.

Alberta

Major changes in medical careers following medical school graduation: when, how often, and why.

Knowledge of the timing of, reasons for, and frequency of major medical-career changes of medical school graduates is useful in considering physician manpower needs. This study reports aspects of the medical-career changes made by a cohort of Alberta medical school graduates who graduated from 1973-1985. Of the 603 (81%) who participated, 160 (27%) reported major medical career changes. Significantly more specialists (35%) than family physicians (18%) made major changes. Forty-two percent made changes during the first year of residency, 21% later in residency, and 29% after entering practice. Reasons cited included general dissatisfaction (47%), lifestyle compatibility (24%), and training and practice experiences (19%). This study indicates that while personal needs and preferences influence changes during residency, practice experience is also important to career choices.

Canada

Nail disorders due to trauma and other acquired conditions of the nail.

Physical and chemical trauma to nails may lead to damage, which presents as various conditions. At times the deformity will imitate systemic disorders or cutaneous diseases. Nail cosmetics and footwear are examples of exogenous factors that can cause such deformity if improperly used. Direct and self-inflicted trauma cause injuries as minor as temporary bands or as severe as permanent nail loss. Prompt treatment can prevent long-term cosmetic and functional damage.

Humans

An evaluation of the clinical problem-solving process using a simulation technique.

Currently, research does not agree as to the extent to which medical content and problem-solving processes underlie clinical problem-solving. The results of research in this area fall into two categories: (1) clinical problem-solving is primarily dependent upon medical content specific within the case, and (2) clinical problem-solving is a skill, or series of skills, which can be applied to all clinical problems. In the study reported in this paper, seventy-one second-year medical students who had completed a 2-year, body-systems oriented curriculum were given an examination designed to measure clinical problem-solving. The results indicated that gathering data on patient history and hypotheses generation were specific skills common to clinical problem-solving, while hypotheses refinement, identification of relevant physical examinations, ordering laboratory investigations and making a diagnosis were case-related.

Clinical Competence