Showing papers in "Canadian Medical Association Journal in 2000"

Canadian normative data for the SF-36 health survey

Abstract: Background: The Medical Outcomes Study 36-item Short Form (SF-36) is a widely used measure of health-related quality of life. Normative data are the key to determining whether a group or an individual scores above or below the average for their country, age or sex. Published norms for the SF-36 exist for other countries but have not been previously published for Canada. Methods: The Canadian Multicentre Osteoporosis Study is a prospective cohort study involving 9423 randomly selected Canadian men and women aged 25 years or more living in the community. The sample was drawn within a 50-km radius of 9 Canadian cities, and the information collected included the SF-36 as a measure of health-related quality of life. This provided a unique opportunity to develop age- and sex-adjusted normative data for the Canadian population. Results: Canadian men scored substantially higher than women on all 8 domains and the 2 summary component scales of the SF-36. Canadians scored higher than their US counterparts on all SF-36 domains and both summary component scales and scored higher than their UK counterparts on 4 domains, although many of the differences are not large. Interpretation: The differences in the SF-36 scores between age groups, sexes and countries confirm that these Canadian norms are necessary for comparative purposes. The data will be useful for assessing the health status of the general population and of patient populations, and the effect of interventions on health-related quality of life.

Meta-analysis of benzodiazepine use in the treatment of insomnia

Abstract: OBJECTIVE: To systematically review the benefits and risks associated with the use of benzodiazepines to treat insomnia in adults. DATA SOURCES: MEDLINE and the Cochrane Controlled Trials Registry were searched for English-language articles published from 1966 to December 1998 that described randomized controlled trials of benzodiazepines for the treatment of insomnia. Key words included "benzodiazepines" (exploded), "randomized controlled trial" and "insomnia." Bibliographies of relevant articles were reviewed for additional studies and manufacturers of benzodiazepines were asked to submit additional randomized controlled trial reports not in the literature. STUDY SELECTION: Articles were considered for the meta-analysis if they were randomized controlled trials involving patients with insomnia and compared a benzodiazepine with placebo or another active agent. Of the 89 trials originally identified, 45 met our criteria, representing a total of 2672 patients. DATA EXTRACTION: Data were extracted regarding the participants, the setting, details of the intervention, the outcomes (including adverse effects) and the methodologic quality of the studies. DATA SYNTHESIS: The meta-analyses of sleep records indicated that, when compared with placebo, benzodiazepines decreased sleep latency by 4.2 minutes (non-significant; 95% confidence interval (CI -0.7 to 9.2) and significantly increased total sleep duration by 61.8 minutes (95% CI 37.4 to 86.2). Patient-reported outcomes were more optimistic for sleep latency; those randomized to benzodiazepine treatment estimated a sleep latency decrease of 14.3 minutes (95% CI 10.6 to 18.0). Although more patients receiving benzodiazepine treatment reported adverse effects, especially daytime drowsiness and dizziness or light-headedness (common odds ratio 1.8, 95% CI 1.4 to 2.4), dropout rates for the benzodiazepine and placebo groups were similar. Cognitive function decline including memory impairment was reported in several of the studies. Zopiclone was not found to be superior to benzodiazepines on any of the outcome measures examined. INTERPRETATION: The use of benzodiazepines in the treatment of insomnia is associated with an increase in sleep duration, but this is countered by a number of adverse effects. Additional studies evaluating the efficacy of nonpharmacological interventions would be valuable.

Secular trends in the body mass index of Canadian children

Abstract: Background: Various changes in society have created the opportunity for more sedentary behaviour and the consumption of food that is high in kilojoules, which may lead to a progressive increase in body mass over time. The purpose of this study was to examine secular changes in the body mass index (BMI) of Canadian children between 1981 and 1996. Methods: Nationally representative data from the 1981 Canada Fitness Survey, the 1988 Campbell9s Survey on the Well-being of Canadians and the 1996 National Longitudinal Survey of Children and Youth were used in the analysis. Regression analyses were used to assess population changes in BMI from 1981 to 1996 for children aged 7–13 years. Changes in the distribution of BMI results were evaluated by plotting the residuals from regression analyses of BMI on age, assessed separately by sex, using the 1981 data as baseline. The proportions of children exceeding the 85th and 95th age- and sex-specific percentiles from the 1981 (baseline) data were also calculated. Results: Since 1981, BMI has increased at the rate of nearly 0.1 kg/m 2 per year for both sexes at most ages, indicating a clear secular trend toward an increase in BMI of Canadian children. The prevalence of overweight among boys increased from 15% in 1981 to 28.8% in 1996 and among girls from 15% to 23.6%. The prevalence of obesity in children more than doubled over that period, from 5% to 13.5% for boys and 11.8% for girls. Interpretation: Secular trends indicate that Canadian children aged 7–13 years are becoming progressively overweight and obese.

Type 2 diabetes mellitus in Canada‚s First Nations: status of an epidemic in progress

Abstract: This review provides a status report on the epidemic of type 2 diabetes mellitus that is affecting many of Canada's First Nations. We focus on the published literature, especially reports published in the past 2 decades, and incorporate data from the Aboriginal Peoples Survey and the First Nations and Inuit Regional Health Survey. We look at the extent and magnitude of the problem, the causes and risk factors, primary prevention and screening, clinical care and education, and cultural concepts and traditional knowledge. The epidemic of type 2 diabetes is still on the upswing, with a trend toward earlier age at onset. Genetic-environmental interactions are the likely cause. Scattered intervention projects have been implemented and evaluated, and some show promise. The current health and social repercussions of the disease are considerable, and the long-term outlook remains guarded. A national Aboriginal diabetes strategy is urgently needed.

The economic burden of physical inactivity in Canada

Abstract: Background: About two-thirds of Canadians are physically inactive. As a risk factor for several chronic diseases, physical inactivity can potentially be a substantial public health burden. We estimated the direct health care costs attributable to physical inactivity in Canada, the number of lives lost prematurely each year that are attributable to a sedentary lifestyle and the effect that a reduction of 10% in inactivity levels (a Canadian objective for 2003) could have on reducing direct health care costs. Methods: We calculated summary relative risk (RR) estimates from prospective longitudinal studies of the effects of physical inactivity on coronary artery disease, stroke, colon cancer, breast cancer, type 2 diabetes mellitus and osteoporosis. We then computed the population-attributable fraction (PAF) for each illness from the summary RR and the prevalence of physical inactivity (i.e., 62%) and applied the PAF to the total direct health care expenditures for 1999 and to the number of deaths in 1995 associated with each disease to determine the health care costs and lives lost prematurely that were directly attributable to physical inactivity. Results: About $2.1 billion, or 2.5% of the total direct health care costs in Canada, were attributable to physical inactivity in 1999. A sensitivity analysis (simultaneously varying each of the health care costs and PAF by ±20%) indicated that the costs could be as low as $1.4 billion and as high as $3.1 billion. About 21 000 lives were lost prematurely in 1995 because of inactivity. A 10% reduction in the prevalence of physical inactivity has the potential to reduce direct health care expenditures by $150 million a year. Interpretation: Physical inactivity represents an important public health burden in Canada. Even modest reductions in inactivity levels could result in substantial cost savings.

Cancer care workers in Ontario: prevalence of burnout, job stress and job satisfaction

Abstract: Background: Cancer Care Ontario’s Systemic Therapy Task Force recently reviewed the medical oncology system in the province. There has been growing concern about anecdotal reports of burnout, high levels of stress and staff leaving or decreasing their work hours. However, no research has systematically determined whether there is evidence to support or refute these reports. To this end, a confidential survey was undertaken. Methods: A questionnaire was mailed to all 1016 personnel of the major providers of medical oncology services in Ontario. The questionnaire consisted of the Maslach Burnout Inventory, the 12-item General Health Questionnaire, a questionnaire to determine job satisfaction and stress, and questions to obtain demographic characteristics and to measure the staff’s consideration of alternative work situations. Results: The overall response rate was 70.9% (681 of 961 eligible subjects): by group it was 63.3% (131/207) for physicians, 80.9% (314/388) for allied health professionals and 64.5% (236/366) for support staff. The prevalence of emotional exhaustion were significantly higher among the physicians (53.3%) than among the allied health professionals (37.1%) and the support staff (30.5%) (p ≤ 0.003); the same was true for feelings of depersonalization (22.1% v. 4.3% and 5.5% respectively) (p ≤ 0.003). Feelings of low personal accomplishment were significantly higher among physicians (48.4%) and allied health professionals (54.0%) than among support staff (31.4%) (p ≤ 0.002). About one-third of the respondents in each group reported that they have considered leaving for a job outside the cancer care system. Significantly more physicians (42.6%) than allied health professionals (7.6%) or support staff (4.5%) stated that they have considered leaving for a job outside the province. Interpretation: The findings support the concern that medical oncology personnel are experiencing burnout and high levels of stress and that large numbers are considering leaving or decreasing their work hours. This is an important finding for the cancer care system, where highly trained and experienced health care workers are already in short supply.

Evidence-based medicine: a commentary on common criticisms

Abstract: Discussions about evidence-based medicine engender both negative and positive reactions from clinicians and academics. Ways to achieve evidence-based practice are reviewed here and the most common criticisms described. The latter can be classified as ”limitations universal to the practice of medicine,” ”limitations unique to evidence-based medicine” and ”misperceptions of evidence-based medicine.” Potential solutions to the true limitations of evidence-based medicine are discussed and areas for future work highlighted.

Development and validation of the Osteoporosis Risk Assessment Instrument to facilitate selection of women for bone densitometry

Abstract: BACKGROUND: Although mass screening for osteoporosis is not recommended among postmenopausal women, there is no consensus on which women should undergo testing for low bone mineral density. The objective of this study was to develop and validate a clinical tool to help clinicians identify which women are at increased risk for osteoporosis and should therefore undergo further testing with bone densitometry. METHODS: Using Ontario baseline data from the Canadian Multicentre Osteoporosis Study, we identified all cognitively normal women aged 45 years or more who had undergone testing with dual-energy x-ray absorptiometry (DXA) at both the femoral neck and the lumbar spine (L1-L4). Participants who had a previous diagnosis of osteoporosis or were taking bone active medication other than ovarian hormones were excluded. The main outcome measure was low bone mineral density (T score of 2 or more standard deviations below the mean for young Canadian women) at either the femoral neck or the lumbar spine. Logistic regression analysis and receiver operating characteristic (ROC) analysis were used to identify the simplest algorithm that would identify women at increased risk for low bone mineral density. RESULTS: The study population comprised 1376 women, of whom 926 were allocated to the development of the tool and 450 to its validation. A simple algorithm based on age, weight and current estrogen use (yes or no) was developed. Validation of this 3-item Osteoporosis Risk Assessment Instrument (ORAI) showed that the tool had a sensitivity of 93.3% (95% confidence interval [CI] 86.3%-97.0%) and a specificity of 46.4% (95% CI 41.0%-51.8%) for selecting women with low bone mineral density. The sensitivity of the instrument for selecting women with osteoporosis was 94.4% (95% CI 83.7%-98.6%). Use of the ORAI represented a 38.7% reduction in DXA testing compared with screening all women in our study. INTERPRETATION: The ORAI accurately identifies the vast majority of women likely to have low bone mineral density and is effective in substantially decreasing the need for all women to undergo DXA testing.

Prevalence and detection of delirium in elderly emergency department patients

Abstract: Background: Delirium is a complex medical disorder associated with high morbidity and mortality among elderly patients. The goals of our study were to determine the prevalence of delirium in emergency department (ED) patients aged 65 years and over and to determine the sensitivity and specificity of a conventional clinical assessment by an ED physician for the detection of delirium in the same population. Methods: All elderly patients presenting to the ED in a primary acute care, university-affiliated hospital who were triaged to the observation room on a stretcher because of the severity of their illness were screened for delirium by a research psychiatrist using the Mini-Mental State Examination and the Confusion Assessment Method. The diagnosis of “delirium” or an equivalent term by the ED physician was determined by 2 methods: completion of a mental status checklist by the ED physician and chart review. The prevalence of delirium and the sensitivity and specificity of the ED physician’s clinical assessment were calculated with their 95% confidence intervals. The demographic and clinical characteristics of patients with detected delirium and those with undetected delirium were compared. Results: A sample of 447 patients was screened. The prevalence of delirium was 9.6% (95% confidence interval 6.9%‐12.4%). The sensitivity of the detection of delirium by the ED physician was 35.3% and the specificity, 98.5%. Most patients with delirium had neurologic or pulmonary diseases, and most patients with detected delirium had neurologic diseases. Interpretation: Despite the relatively high prevalence of delirium in elderly ED patients, the sensitivity of a conventional clinical assessment for this condition is low. There is a need to improve the detection of delirium by ED physicians.

Comparison of self-collected vaginal, vulvar and urine samples with physician-collected cervical samples for human papillomavirus testing to detect high-grade squamous intraepithelial lesions

Abstract: Background: Certain types of human papillomavirus (HPV) in cervical samples are strongly associated with squamous intraepithelial lesions (SIL) and invasive cervical carcinoma. We determined and compared the test characteristics of testing for HPV with samples obtained by patients and with samples obtained by their physicians. Methods: In a consecutive series of women referred to a colposcopy clinic at a teaching hospital because of abnormalities on cervical cytologic screening, 200 agreed to collect vulvar, vaginal and urine samples for HPV testing. The physician then collected cervical samples for HPV testing, and colposcopy, with biopsy as indicated, was performed. Presence of HPV was evaluated using the hybrid capture II assay (Digene Corp., Silver Spring, Md.) with a probe cocktail for 13 carcinogenic types. Cervical specimens were also tested for HPV by polymerase chain reaction and hybridization with type-specific probes. Cervical smears for cytologic examination were obtained from all women. Results: High-grade lesions (high-grade squamous intraepithelial lesions [HSIL], equivalent to cervical intraepithelial neoplasia [CIN] grade 2 or 3, and adenocarcinoma) were found in 58 (29.0%) of the 200 women. Carcinogenic types of HPV were detected in the self-collected vaginal samples of 50 (86.2%) of these 58 women, in the self-collected vulvar samples of 36 (62.1%) and in the selfcollected urine samples of 26 (44.8%). Carcinogenic types of HPV were detected in the cervical samples collected by physicians for 57 (98.3%) of these 58 women. The remaining 142 women (71.0%) had normal findings or low-grade squamous intraepithelial lesions (LSIL, CIN grade 1). Test results were negative or noncarcinogenic types of HPV were detected in the self-collected vaginal samples of 76 (53.5%) of these 142 women, in the self-collected vulvar samples of 89 (62.7%) and in the self-collected urine samples of 99 (69.7%). The sensitivity for self-collected samples ranged from 44.8% to 86.2%, and the specificity from 53.5% to 69.7%. For the samples collected by physicians, the sensitivity was 98.3% and the specificity 52.1%. The self-sampling methods were generally acceptable to the women: 98.4% of respondents (126/128) deemed urine sampling acceptable, 92.9% (118/127) found vulvar sampling acceptable, and 88.2% (112/127) found vaginal sampling acceptable. Interpretation: Self-collection of samples for HPV testing was acceptable to women attending a colposcopy clinic for investigation of suspected cervical lesions and shows sufficient sensitivity to warrant further evaluation as a screening test for cervical cancer prevention programs.

The validity of a sore throat score in family practice

Abstract: Background: Reducing the number of antibiotic prescriptions given for common respiratory infections has been recommended as a way to limit bacterial resistance. This study assessed the validity of a previously published clinical score for the management of infections of the upper respiratory tract accompanied by sore throat. The study also examined the potential impact of this clinical score on the prescribing of antibiotics in community-based family practice. Methods: A total of 97 family physicians in 49 Ontario communities assessed 621 children and adults with a new infection of the upper respiratory tract accompanied by sore throat and recorded their prescribing decisions. A throat swab was obtained for culture. The sensitivity and specificity of the score approach in this population were compared with previously published results for patients seen at an academic family medicine centre. In addition, physicians’ prescribing practices and their recommendations for obtaining throat swabs were compared with score-based recommendations. Results: Of the 621 cases of new upper respiratory tract infection and sore throat, information about prescriptions given was available for only 619; physicians prescribed antibiotics in 173 (27.9%) of these cases. Of the 173 prescriptions, 109 (63.0%) were given to patients with culture-negative results for group A Streptococcus. Using the score to determine management would have reduced prescriptions to culture-negative patients by 63.7% and overall antibiotic prescriptions by 52.3% (both p < 0.01). Culturing of throat samples would have been reduced by 35.8% (p < 0.01). There was no statistically significant difference in the sensitivity or specificity of the score approach between this community-based population (sensitivity 85.0%, specificity 92.1%) and an academic family medicine centre (sensitivity 83.1%, specificity 94.3%). Interpretation: An explicit clinical score approach to the management of patients presenting with an upper respiratory tract infection and sore throat is valid in community-based family practice and could substantially reduce the unnecessary prescribing of antibiotics for these conditions.

Prevalence and predictors of human papillomavirus infection in women in Ontario, Canada

Abstract: Background: Human papillomavirus (HPV) is thought to be the primary cause of cervical intraepithelial neoplasia and cervical cancer. We determined the agespecific prevalence of HPV infection and its risk factors in Ontario women. Methods: We obtained 2 cervical specimens from randomly selected women (in 5year age categories, from 15 to 49 years) who were being seen in 32 family practices for cytologic screening. The specimens were tested for carcinogenic HPV by the hybrid capture II assay (Digene Corp., Silver Spring, Md.) and by polymerase chain reaction (PCR) and genotyping. Results: Of 1004 women eligible to participate, samples were obtained from 955 (95.1%). The prevalence of HPV (as determined by the hybrid capture II method) was highest, at 24.0% (95% confidence interval [CI] 16.5% to 31.5%), among women 20 to 24 years of age and was progressively lower in older age groups, reaching 3.4% (95% CI 0.1% to 6.7%) in women 45 to 49 years old. The prevalence of HPV (any type) as determined by PCR showed a similar pattern but was significantly higher (p = 0.01) among women 45 to 49 years old than among those 40 to 44 years old (13.0% [95% CI 6.4% to 19.6%] v. 3.3% [95% CI 0.1% to 6.5%]). Risk factors for positivity with the hybrid capture II method were never-married status, divorced or separated status, more than 3 lifetime partners, more than 1 partner in the preceding year, cigarette smoking and current use of oral contraceptives. The presence of squamous intraepithelial lesions on cytologic examination was strongly associated with positivity with the hybrid capture II assay (odds ratio 96.0, 95% CI 22.3 to 413.4; p < 0.01). Interpretation: The highest prevalence of HPV was 24.0%, in women 20 to 24 years old. Risk factors supported a sexual mode of transmission, and there was a strong association between HPV and abnormal cervical cytologic results.

Investigation and treatment of osteoporosis in patients with fragility fractures

Abstract: Background: Many patients who have undiagnosed osteoporosis and a recent fragility fracture present to fracture clinics in Canadian hospitals, where the focus of management is on fracture care. The rate of diagnosis and treatment of osteoporosis in this patient group is unknown. Methods: Patients who presented with fractures at sites consistent with fragilitytype fractures were identified through a retrospective chart review of fracture clinic visits in 3 Ontario community hospitals in selected weeks in February and November 1996 and August and May 1997. These patients were contacted by mail and telephone follow-up to obtain consent to participate in a telephone interview. Patients were excluded if the index fracture had been traumatic, if they were younger than 18 years, or if they had medical conditions known to be associated with secondary bone loss. Eligible patients were questioned about their history of prior fractures, diagnosis of osteoporosis, and investigation and treatment of osteoporosis before or after the index fracture. Results: Among 2694 fracture clinic visits, we identified 228 patients (8.4%) with fragility-type fractures. Of the 228, 128 (56.1%) were contacted and agreed to participate in an interview about 1 year from the date of the index fracture. Of the 128 patients, 108 (83 postmenopausal and 13 premenopausal women and 12 men) were confirmed as eligible. Of the 108, 43 had experienced 53 fractures in addition to the index fracture in the preceding 10 years, of which 71% were of the fragility type. At interview, only 20 (18.5%) (all postmenopausal women) of the 108 patients reported that they had received a diagnosis of osteoporosis. Of the 20, 90% and 45% respectively had been advised to take calcium and vitamin D supplements; 8 (40%) were receiving hormone replacement therapy (HRT), and 8 (40%) were taking bisphosphonates. Of the 88 patients who had not received a diagnosis of osteoporosis, 4 (4.5%) were receiving HRT, none was taking bisphosphonates, and less than 20% had been advised to take supplemental calcium or vitamin D. Interpretation: In a representative sample of patients at urban fracture clinics, less than 20% who presented with a fragility-type fracture had undergone investigatation and adequate treatment of osteoporosis at 1-year follow-up. Since previous fracture significantly increases the risk for future fracture, this clearly is a deficiency in management. Through improved identification and treatment of patients with osteoporosis-related fractures who present to fracture clinics, there is a significant opportunity to reduce the rates of illness and death associated with this condition.

Recommendations for the management and treatment of dyslipidemia: Report of the Working Group on Hypercholesterolemia and Other Dyslipidemias

Abstract: Despite the steady decline in the rate of death from coronary artery disease (CAD) during the past 25 years, cardiovascular disease remains the leading cause of death in Canada, accounting for 37% of total deaths.[1][1] Although the age-adjusted rate of death from cardiovascular disease is declining

Frequent users of the emergency department: a program to improve care and reduce visits

Abstract: The authors describe a case-management program for frequent users of the emergency department. The study had a single-subject design, with evaluation for each patient of the number of visits to the emergency department for a 12-month period before referral to the program and a similar period after implementation of an individualized care plan. Referrals were made on the basis of 2 or more of the following criteria: chronic medical condition, complex medical condition, drug-seeking behaviour, violent behaviour and abusive behaviour. A multidisciplinary team developed the individualized care plans. Twenty-four patients agreed to participate. For the 12-month period before their referral, these patients accounted for a total of 616 (median 26.5) visits to the emergency department; for a similar period after implementation of the care plans, they accounted for 175 (median 6.5) visits. The difficult-case management program appeared to be effective in reducing the total number of visits to the emergency department during the study period and in improving the care for these patients.

Raves: a review of the culture, the drugs and the prevention of harm

Abstract: Raves are all-night dance parties attended by large numbers of youth, sometimes in excess of 20,000. The rave scene, which is international in scope, is distinguished by clandestine venues, hypnotic electronic music and the liberal use of drugs such as ecstasy (3,4-methylenedioxymethamphetamine), GHB (gamma-hydroxybutyrate) and ketamine. Several rave-related deaths in Canada in 1999 alerted health authorities, parents and police to the health risks of rave attendance. Family physicians, emergency physicians and pediatricians should have some understanding of raves, the drugs and the health risks so they can effectively counsel and treat patients. The rave culture in Canada and the drugs commonly used at raves are reviewed, and strategies and initiatives for harm reduction are discussed.

Intervening to reduce weight gain in pregnancy and gestational diabetes mellitus in Cree communities: an evaluation.

Abstract: Background: A high prevalence of gestational diabetes mellitus and type 2 diabetes has been observed among the Cree of James Bay, Quebec. To address this problem, a diet and activity intervention during pregnancy, which was based on social learning theory, was initiated in 4 Cree communities. Methods: A prospective intervention compared dietary, weight and glycemic indicators for 107 control subjects and for 112 women who received the intervention during the course of their pregnancy. A control period in 4 communities (July 1995–March 1996) was followed by an intervention period (April 1996–January 1997) when subjects were offered regular, individual diet counselling, physical activity sessions and other activities related to nutrition. Results: The intervention and control groups did not differ at baseline regarding their mean age (24.3 years [SD 6.29] v. 23.8 years [SD 5.86]), mean prepregnancy weight (81.0 kg [SD 19.46] v. 78.9 kg [SD 17.54]) and mean gestational age at recruitment (17.1 weeks [SD 7.06] v. 18.5 weeks [SD 6.92]). The intervention did not result in differences in diet measured at 24–30 weeks9 gestation, rate of weight gain over the second half of pregnancy (0.53 kg per week [SD 0.32] v. 0.53 kg per week [SD 0.27]) or plasma glucose level (50 g oral glucose screen) between 24 and 30 weeks (7.21 mmol/L [SD 2.09] v. 7.43 mmol/L [SD 2.10]). Mean birth weights were similar (3741 g [SD 523] v. 3686 g [SD 686]), as was maternal weight at 6 weeks post partum (88.1 kg [SD 16.8] v. 86.4 kg [SD 19.0]). The only changes in dietary intake were a reduction in caffeine (pregnancy) and an increase in folate (post partum). Interpretation: This intervention had only a minor impact on diet; finding ways of encouraging appropriate body weight and activity levels remains a challenge.

Causes of Alzheimer's disease

Abstract: It is now understood that genetic factors play a crucial role in the risk of developing Alzheimer's disease (AD). Rare mutations in at least 3 genes are responsible for early-onset familial AD. A common polymorphism in the apolipoprotein E gene is the major determinant of risk in families with late-onset AD, as well as in the general population. Advanced age, however, remains the major established risk factor for AD, although environmental variables may also have some role in disease expression. Some pathogenic factors directly associated with aging include oxidative damage and mutations in messenger RNA. Other factors unrelated to the aging process may, in the future, be amenable to therapeutic intervention by way of estrogen replacement therapy for postmenopausal women, anti-inflammatory drug therapy and reducing vascular risk factors. Older theories, such as aluminum playing a role in the pathogenesis of AD, have been mostly discarded as our understanding of pathogenic mechanisms of AD has advanced.

The role of DNA amplification technology in the diagnosis of infectious diseases.

Abstract: NUCLEIC ACID AMPLIFICATION AND DETECTION METHODS developed in the past decade are useful for the diagnosis and management of a variety of infectious diseases. The most widely used of these methods is the polymerase chain reaction (PCR). PCR assays can detect rapidly and accurately the presence of fastidious and slowgrowing microorganisms, such as Chlamydia, mycoplasmas, mycobacteria, herpesviruses and enteroviruses, directly from clinical specimens. Commercial PCR assays for the diagnosis of tuberculosis and genital C. trachomatis infection are now routinely used in many diagnostic laboratories. Assays have also been developed that can detect antimicrobial resistance and are used to identify the cause of infection by organisms that cannot be cultivated. The value of viral load measurement by nucleic acid amplification in the management of patients with HIV infection or hepatitis C has also been well established. However, evaluations of this technology for rapid microbial diagnosis have generally been limited by small samples, and the cost of these assays may be as high as Can$125 per test. As nucleic acid amplification methods continue to evolve, their role in the diagnosis and management of patients with infectious diseases and their impact on clinical outcomes will become better defined.

Effectiveness of massage therapy for subacute low-back pain: a randomized controlled trial

Abstract: BACKGROUND: The effectiveness of massage therapy for low-back pain has not been documented. This randomized controlled trial compared comprehensive massage therapy (soft-tissue manipulation, remedial exercise and posture education), 2 components of massage therapy and placebo in the treatment of subacute (between 1 week and 8 months) low-back pain. METHODS: Subjects with subacute low-back pain were randomly assigned to 1 of 4 groups: comprehensive massage therapy (n = 25), soft-tissue manipulation only (n = 25), remedial exercise with posture education only (n = 22) or a placebo of sham laser therapy (n = 26). Each subject received 6 treatments within approximately 1 month. Outcome measures obtained at baseline, after treatment and at 1-month follow-up consisted of the Roland Disability Questionnaire (RDQ), the McGill Pain Questionnaire (PPI and PRI), the State Anxiety Index and the Modified Schober test (lumbar range of motion). RESULTS: Of the 107 subjects who passed screening, 98 (92%) completed post-treatment tests and 91 (85%) completed follow-up tests. Statistically significant differences were noted after treatment and at follow-up. The comprehensive massage therapy group had improved function (mean RDQ score 1.54 v. 2.86-6.5, p < 0.001), less intense pain (mean PPI score 0.42 v. 1.18-1.75, p < 0.001) and a decrease in the quality of pain (mean PRI score 2.29 v. 4.55-7.71, p = 0.006) compared with the other 3 groups. Clinical significance was evident for the comprehensive massage therapy group and the soft-tissue manipulation group on the measure of function. At 1-month follow-up 63% of subjects in the comprehensive massage therapy group reported no pain as compared with 27% of the soft-tissue manipulation group, 14% of the remedial exercise group and 0% of the sham laser therapy group. INTERPRETATION: Patients with subacute low-back pain were shown to benefit from massage therapy, as regulated by the College of Massage Therapists of Ontario and delivered by experienced massage therapists.

The Internet and evidence-based decision-making: a needed synergy for efficient knowledge management in health care.

Abstract: The Internet is introducing new ways for humans to interact with machines and to communicate with each other. In health care the Internet is providing unprecedented opportunities to access information, improve decisions, and enhance communication among decision-makers and the people affected by

Why are antibiotics prescribed for asymptomatic bacteriuria in institutionalized elderly people?: A qualitative study of physicians' and nurses' perceptions

Abstract: Background: Antibiotic therapy for asymptomatic bacteriuria in institutionalized elderly people has not been shown to be of benefit and may in fact be harmful; however, antibiotics are still frequently used to treat asymptomatic bacteriuria in this population. The aim of this study was to explore the perceptions, attitudes and opinions of physicians and nurses involved in the process of prescribing antibiotics for asymptomatic bacteriuria in institutionalized elderly people. Methods: Focus groups were conducted among physicians and nurses who provide care to residents of long-term care facilities in Hamilton, Ont. A total of 22 physicians and 16 nurses participated. The focus group discussions were tape-recorded, and the transcripts of each session were analysed for issues and themes emerging from the text. Content analysis using an open analytic approach was used to explore and understand the experience of the focus group participants. The data from the text were then coded according to the relevant and emergent themes and issues. Results: We observed that the ordering of urine cultures and the prescribing of antibiotics for residents with asymptomatic bacteriuria were influenced by a wide range of nonspecific symptoms or signs in residents. The physicians felt that the presence of these signs justified a decision to order antibiotics. Nurses played a central role in both the ordering of urine cultures and the decision to prescribe antibiotics through their awareness of changes in residents9 status and communication of this to physicians. Education about asymptomatic bacteriuria was viewed as an important priority for both physicians and nurses. Interpretation: The presence of nonurinary symptoms and signs is an important factor in the prescription of antibiotics for asymptomatic bacteriuria in institutionalized elderly people. However, no evidence exists to support this reason for antibiotic treatment. Health care providers at long-term care facilities need more education about antibiotic use and asymptomatic bacteriuri

Sudden neck movement and cervical artery dissection

Abstract: Two recent deaths from artery dissection following neck manipulation by chiropractors have focused media and medical attention on the relation between sudden neck movement and cervical artery dissection. Although the first case of carotid artery dissection due to chiropractic neck manipulation was

Emerging relations between infectious diseases and coronary artery disease and atherosclerosis

Abstract: Cardiovascular disease is the leading cause of death in developed countries. The cause is multifactorial. A substantial proportion of patients with coronary artery disease (CAD) do not have traditional risk factors. Infectious diseases may play a role in these cases, or they may intensify the effect of other risk factors. The association of CAD and Chlamydia pneumoniae infection is firmly established, but causality is yet to be proven. The link with other infectious agents or conditions, such as cytomegalovirus, herpes simplex virus, Helicobacter pylori and periodontitis, is more controversial. Cytomegalovirus infection is more strongly linked than native CAD to coronary artery restenosis after angioplasty and to accelerated CAD after cardiac transplantation. However, new data on this topic are appearing in the literature almost every month. The potential for novel therapeutic management of cardiovascular disease and stroke is great if infection is proven to cause or accelerate CAD or atherosclerosis. However, physicians should not "jump the gun" and start using antibiotic therapy prematurely for CAD. The results of large randomized clinical trials in progress will help establish causality and the benefits of antimicrobial therapy in CAD.

Expansion of gambling in Canada: implications for health and social policy

Abstract: Canada experienced a dramatic increase in legalized gambling in the 1990s, primarily because of governments' need to increase revenue without additional taxation. This article examines gambling from a public health perspective. The major public health issues include gambling addiction, family dysfunction and gambling by youth. Debates have emerged about the health, social and economic costs and benefits of gambling. Stakeholder and social policy groups have expressed concern about the impact of expanded gambling on the quality of life of individuals, families and communities. Epidemiological studies show that the prevalence of gambling in the general adult population is low but increasing. Of particular concern is the high though steady prevalence of gambling among youth. New technologies have been linked to gambling-related problems such as addiction to gambling by video lottery terminals. Gambling by means of the Internet represents another emerging issue. The article concludes with recommendations for health and social policy related to gambling. These recommendations incorporate a broad public health approach to create a strong research program and to balance risks and benefits.

Knowledge of cardiovascular disease risk factors among the Canadian population: relationships with indicators of socioeconomic status.

Abstract: Background: We examined the ability of adult Canadians to recall cardiovascular disease risk factors to determine the associations between their ability to recall risk factors for cardiovascular disease and their socioeconomic status. Methods: This study used the database assembled by the Canadian Heart Health Surveys Research Group between 1986 and 1992 - a stratified representative sample comprising 23 129 Canadian residents aged 18 to 74. Nurses administered a standard questionnaire asking respondents to list the major risk factors for cardiovascular disease: fat in food, smoking, lack of exercise, excess weight, elevated blood cholesterol and high blood pressure. Six logistic regressions examined the multivariate associations between ability to recall each risk factor with education, income adequacy, occupation, sex, age, marital status and province of residence. Results: More people knew about the behaviour-related risk factors for cardiovascular disease than about the physiologic risk factors: 60% recalled fat in food, 52% smoking and 41% lack of exercise, but only 32% identified weight, 27% cholesterol and 22% high blood pressure. Education was the socioeconomic status indicator most strongly and consistently associated with the ability to recall risk factors for cardiovascular disease. The odds ratios of reporting an association of the risks between people with elementary education and those with university degrees varied between 0.16 (95% confidence interval 0.12 to 0.22) for lack of exercise to 0.55 (95% confidence interval 0.39 to 0.77) for smoking. Interpretation: People in categories at greater risk of cardiovascular disease, such as those aged 65 or more or those with only elementary education, are less able to recall important cardiovascular disease risk factors.

Distribution of cardiovascular disease risk factors by socioeconomic status among Canadian adults

Abstract: BACKGROUND: This study was designed to describe the distribution of risk factors for cardiovascular disease by socioeconomic status in adult men and women across Canada using the Canadian Heart Health Surveys Database. METHODS: The data were derived from provincial cross-sectional surveys done between 1986 and 1992. Data were obtained through a home interview and a clinic visit using a probability sample of 29,855 men and women aged 18-74 years of whom 23,129 (77%) agreed to participate. The following risk factors for cardiovascular disease were considered: elevated total plasma cholesterol (greater than 5.2 mmol/L), regular current cigarette smoking (one or more daily), elevated diastolic or systolic blood pressure (140/90 mm Hg), overweight (body mass index and lack of leisure-time physical activity [less than once a week in the last month]). Education and income adequacy were used as measures of socioeconomic status and mother tongue as a measure of cultural affiliation. RESULTS: For most of the risk factors examined, the prevalence of the risk factors was inversely related to socioeconomic status, but the relationship was stronger and more consistent for education than for income. The inverse relationship between socioeconomic status and the prevalence of the risk factors was particularly strong for smoking and overweight, where a gradient was observed: 46% (standard error [SE] 1.4) of men and 42% (SE 4.3) of women who had not completed secondary school were regular smokers, but only 12% (SE 1.0) of men and 13% (SE 0.9) of women with a university degree were regular smokers. Thirty-nine percent (SE 1.4) of men and 19% (SE 3.8) of women who had not completed secondary school were overweight, compared with 26% (SE 2.6) of male and 19% of female university graduates. The prevalence of leisure-time physical inactivity and elevated cholesterol was highest in both men and women in the lowest socioeconomic category, particularly by level of education. INTERPRETATION: The differences in the prevalence of risk factors for cardiovascular disease between socioeconomic groups are still important in Canada and should be considered in planning programs to reduce the morbidity and mortality from cardiovascular disease.

Medicine under threat: professionalism and professional identity

Abstract: The professions have never been more important to the well-being of society. Professional knowledge and expertise are at the core of contemporary society. How such professional expertise is developed, how it is deployed, by whom it is deployed and for what ends are among the most pressing issues

Child hunger in Canada: results of the 1994 National Longitudinal Survey of Children and Youth

Abstract: Background: In Canada, hunger is believed to be rare. This study examined the prevalence of hunger among Canadian children and the characteristics of, and coping strategies used by, families with children experiencing hunger. Methods: The data originated from the first wave of data collection for the National Longitudinal Survey of Children and Youth, conducted in 1994, which included 13 439 randomly selected Canadian families with children aged 11 years or less. The respondents were asked about the child’s experience of hunger and consequent use of coping strategies. Sociodemographic and other risk factors for families experiencing hunger, use of food assistance programs and other coping strategies were analyzed by means of multiple logistic regression analysis. Results: Hunger was experienced by 1.2% (206) of the families in the survey, representing 57 000 Canadian families. Single-parent families, families relying on social assistance and off-reserve Aboriginal families were overrepresented among those experiencing hunger. Hunger coexisted with the mother’s poor health and activity limitation and poor child health. Parents offset the needs of their children by depriving themselves of food. Interpretation: Physicians may wish to use these demographic characteristics to identify and assist families with children potentially at risk for hunger.

Primary hyperparathyroidism: pathophysiology and impact on bone

Abstract: Primary hyperparathyroidism has been associated with bone loss, especially at cortical skeletal sites. Results from studies evaluating the mineral density of cancellous bone have been more difficult to interpret. Most densitometry studies support the concept that the parathyroid hormone appears to be catabolic at cortical sites and may have anabolic effects at cancellous bone sites. Studies completed to date, however, have been limited by design, definitions of fracture and inadequate control groups. Primary hyperparathyroidism is now increasingly being detected during the asymptomatic phase. The need for parathyroidectomy has been questioned in such patients because there may be no disease progression in the absence of surgery. Medical management of primary hyperparathyroidism has to date been limited to estrogen replacement therapy in postmenopausal women. Identification of the calcium receptor has improved our understanding of calcium homeostasis, and significant reductions in calcium receptor levels have been detected in parathyroid adenomas. Thus, a new class of therapeutics may include the calcimimetic agents. Bisphosphonates are also currently being evaluated with regard to their impact on fracture prevention and their beneficial effects on bone mineral density.