Use of hormonal therapy in senior breast cancer patients treated with or without radiotherapy.

PURPOSE: Breast cancer treatment guidelines state that radiotherapy (rt) can reasonably be omitted in selected women 70 years of age and older if they take adjuvant endocrine therapy (aet) for 5 years. We aimed to assess persistence and adherence to aet in women 70 years of age and older, and to examine differences between rt receivers and non-receivers. METHODS: Quebec's medical service and pharmacy claims databases were used to identify seniors undergoing breast-conserving surgery (1998-2005) and initiating aet. Cox proportional hazards models were used to identify predictors of aet non-persistence. RESULTS: Of 3180 women who initiated aet (mean age: 77.5 years), 28% did not receive rt. During the subsequent 5 years, 32% of patients who initiated aet did not persist, 2% filled only a single prescription, and 22% switched medications. Compared with rt receivers, non-receivers discontinued more often (35.5% vs. 30.1%) and earlier (1.4 years vs. 1.6 years). They also became nonadherent earlier (medication possession ratio < 80% at year 3 vs. at year 5). Predictors of nonpersistence included rt omission [hazard ratio (hr): 1.26; 95% confidence interval (ci): 1.09 to 1.46]; age (hr per decade increase: 1.15; 95% ci: 1.01 to 1.31); new medications (hr per medication: 1.01; 95% ci: 1.00 to 1.02); and hospitalizations during aet, (hr per hospitalization: 1.08; 95% ci: 1.05 to 1.11). In a subanalysis of rt non-receivers, significant predictors included hospitalizations (hr: 1.07; 95% ci: 1.02 to 1.12) and medications at aet start (hr: 0.94; 95% ci: 0.91 to 0.97). CONCLUSIONS: Suboptimal use of aet was observed in at least one third of women. In rt non-receivers, aet use was worse than it was in rt receivers. Initiation of new medications and hospitalizations increased the risk of non-persistence.

Factors influencing the quality of local management of ductal carcinoma in situ: a cohort study.

BACKGROUND: Guidelines recommend radiotherapy (rt) after breast-conserving surgery (bcs) for optimal control of ductal carcinoma in situ (dcis). The aim of the present study was to characterize the rates of rt consideration and administration, and to identify factors influencing those rates in a cohort of women diagnosed between 1998 and 2005 in Quebec. METHODS: Quebec's medical service claims and discharge abstract database were used. Using consultation for rt as an indicator for rt consideration, odds ratios (ors) and 95% confidence intervals (cis) were estimated using a generalized estimating equations regression model. RESULTS: Of 4139 women analyzed (mean age: 58 years), 3435 (83%) received a consultation for rt, and 3057 of them (89%) proceeded with treatment. The rate of rt consideration increased by 7.1% over the study period, with notable differences in the various age groups. Relative to women 50-69 years of age, the ors for being considered for rt were, respectively, 0.89 (95% ci: 0.71 to 1.12), 0.71 (95% ci: 0.55 to 0.92), and 0.20 (95% ci: 0.14 to 0.31) for women younger than 50, 70-79, and 80 years of age and older. Distance to a designated breast care centre lowered the probability of rt consideration, but the presence of comorbidities did not. A surgeon's volume of bcss increased the probability of being considered for rt by 7% for every 10 such procedures performed (or: 1.07; 95% ci: 1.04 to 1.11). CONCLUSIONS: Consideration for rt has increased over time. However, older women (despite being in good health) and those living far from a designated breast care centre or having a low-case-volume surgeon were less likely to be considered for rt.

A population-based assessment of systemic lupus erythematosus incidence and prevalence--results and implications of using administrative data for epidemiological studies.

OBJECTIVES: To estimate (i) systemic lupus erythematosus (SLE) incidence and prevalence using multiple sources of population-based administrative data; (ii) the sensitivity and specificity of case ascertainment methods; and (iii) variation in performance of each ascertainment approach, according to patient and physician characteristics. METHODS: We examined the physician billing and hospitalization databases of the province of Quebec (1994-2003) covering all health care beneficiaries (approximately 7.5 million). We compared various approaches to ascertain SLE cases, using information from each database separately or combining sources; we then estimated the sensitivity and specificity of these alternative approaches. We used regression models to determine if sensitivity was independently influenced by patient or physician characteristics. RESULTS: Using billing data, we calculated SLE incidence at 3.0/100,000 person-years [95% confidence interval (CI) 2.6-3.4]; prevalence was 32.8/100,000 persons, in 2003. Results were similar using hospitalization data. However, only a proportion of prevalent cases were identified as having SLE by both methods. Combining cases from billing and hospitalization data, we found a prevalence of 51/100,000 in 2003. Our latent class regression model estimated a prevalence of 44.7/100,000 (95% CI 37.4-54.7). We found high specificity for SLE diagnoses across all strategies and data sources; sensitivity ranged from 42.1% to 67.6%, and was independently influenced by both patient and physician characteristics. CONCLUSIONS: In observational studies, particularly with administrative databases, SLE incidence and prevalence estimates differ considerably, according to the approach for case ascertainment. In the absence of gold standards, statistical modelling can provide sensitivity and specificity estimates for different approaches.

Identification of persons with cardiorespiratory conditions who are at risk of dying from the acute effects of ambient air particles.

This study was undertaken to identify subgroups of the population susceptible to the effects of ambient air particles. Fixed-site air pollution monitors in Montreal, Quebec, Canada, provided daily mean levels of various measures of particulates and gaseous pollutants. Total sulfates were also measured daily (1986-1993) at a monitoring station 150 km southeast of the city (Sutton, Quebec, Canada). We used coefficient of haze (COH), extinction coefficient, and Sutton sulfates to predict fine particles and sulfates from a fine particles model for days that were missing. We used the universal Quebec medicare system to obtain billings and prescriptions for each Montreal resident who died in the city from 1984 to 1993. These data were then used to define cardiovascular and respiratory conditions that subjects had before death. Using standard Poisson regression time-series analyses, we estimated the association between daily nonaccidental mortality and daily concentrations of particles in the ambient air among persons with cardiovascular and respiratory conditions diagnosed before death. We found no persuasive evidence that daily mortality increased when ambient air particles were elevated for subgroups of persons with chronic upper respiratory diseases, airways disease, cerebrovascular diseases, acute coronary artery disease, and hypertension. However, we found that daily mortality increased linearly as concentrations of particles increased for persons who had acute lower respiratory diseases, chronic coronary artery diseases (especially in the elderly), and congestive heart failure. For this latter set of conditions, the mean percent increase in daily mortality (MPC) for an increase in the COH across its interquartile range (18.5 COH units per 327.8 linear meters), averaged over the day of death and the 2 preceding days, was MPC = 5.09% [95% confidence interval (CI) 2.47-7.79%], MPC = 2.62 (95% CI 0.53-4.75%), and MPC = 4.99 (95% CI 2.44-7.60%), respectively. Adjustments for gaseous pollutants generally attenuated these associations, although the general pattern of increased daily mortality remained. In addition, there appeared to be a stronger association in the summer season. The positive associations found for persons who had acute lower respiratory diseases and congestive heart failure are consistent with some prevailing hypotheses and may also be consistent with recent toxicologic data implicating endothelins. Further epidemiologic studies are required to confirm these findings.

The feasibility of using a double blind experimental cross-over design to study interventions for sick building syndrome.

Methodological problems have limited scientific investigation of the causes of and solutions for sick building syndrome. The feasibility of using an experimental double blind cross-over study to resolve many of these methodological problems was assessed in a pilot study. The experimental intervention was to vary the amount of outdoor air from 10 cubic feet per minute per person (cfmpp) to 20 cfmpp or 50 cfmpp by central manipulation of the building heating, ventilation and air-conditioning (HVAC) system. Over 6 consecutive study weeks, 2 trials of rates were administered in random order. Study subjects and investigators of the study were blinded to intervention sequence. Unblinding, office environment rating and symptom occurrence were measured weekly. Of 305 eligible workers, 254 participated. Problems were encountered in delivering the lowest dose of ventilation due to building leakage. The prevalence of symptoms diminished steadily over the 6 study weeks, time trends which could be controlled by recommended design modifications. Blinding to the intervention was successfully maintained. Weekly non-response did not introduce a response bias but reduced the number of subjects available for analysis by one-third for each trial. We conclude that this design, with certain modifications, is feasible to evaluate many proposed interventions for sick building syndrome.

The use of prescription claims databases in pharmacoepidemiological research: the accuracy and comprehensiveness of the prescription claims database in Québec.

Despite the potential benefits of using prescription claims databases for pharmacoepidemiological research, little work has been reported on the nature of available information or its accuracy. The purpose of this study was to describe information contained within the prescription claims database in Québec, and to assess the accuracy of drug information that might be used to monitor drug exposure and physician prescribing. The comprehensiveness of the prescriptions claims database was assessed by examining 1,917,214 records of dispensed prescriptions for a regionally stratified random sample of 65,349 Québec elderly in 1990. We found that values in key fields (individual identifiers, drug, quantity, date dispensed and duration) were missing or out of range in 0-0.4% of records. The accuracy of data were examined in 723 prescriptions filled by 306 elderly patients attending one internal medicine clinic. Of these prescriptions, 83% were filled by the patient and correctly identified the patient and drug and in 89% of these 599 records, the prescribing physician was correctly identified. The quantity and duration of the prescriptions were accurate in 69.1% and 72.1% of records, respectively. We conclude that the prescription claims database in Québec may represent one of the most accurate means of determining drugs dispensed to individuals. There may be limitations in using this database for dosing information.

Using medical services claims to assess injuries in the elderly: sensitivity of diagnostic and procedure codes for injury ascertainment.

The sensitivity of using physician claims data for injury ascertainment was examined in a cohort of 1,181 elderly who were treated in the emergency department of one of 10 hospitals for injuries in 1993-1994. The clinical record of the type and date of injury was compared with diagnostic and procedure codes in the Quebec health insurance agency records of physician billing claims for the same patients. The proportion of patients correctly classified by claims data was determined for the exact date of injury and for a time window around the date of injury. The most common injuries were fractures (55.4%) and lacerations (19.3%), and 78.9% of injuries were fall related. Overall, the combination of treatment procedure codes and diagnostic codes provided the most sensitive measure of injury occurrence; a sensitivity of 67.3% for the exact date and 81.3% for an expanded data window (95.6% of injuries were within -1 day to +3 days of the injury date). Sensitivity varied by injury type form a low of 14% for abrasions to a high of 97.2% for hip fractures. The combination of diagnostic and procedure codes in physician claims is a sensitive indicator of some common injuries that would not be documented in hospitalization databases.

Survival after percutaneous endoscopic gastrostomy among older residents of Quebec.

CONTEXT: Percutaneous endoscopic gastrostomy has become a mainstay of nutritional support for individuals with swallowing dysfunction. There is little population-based data to guide the use of this intervention in older individuals. OBJECTIVE: To describe the use of percutaneous endoscopic gastrostomy among older residents of Quebec and to evaluate patient characteristics associated with subsequent survival and hospital discharge. DESIGN: A population-based cohort study. SETTING: Quebec, Canada. PATIENTS: 175 individuals with a billing claim for percutaneous endoscopic gastrostomy performed in 1993. MEASUREMENTS: Billing and hospitalization databases were used to collect patient characteristics, medical diagnoses, discharge destinations, and dates of death. The relationships between demographic and diagnostic variables before gastrostomy, and subsequent survival and discharge home, were evaluated using survival analysis. RESULTS: Median survival after gastrostomy was 210 days. Mortality at 30 days was 18.3%. Decreased survival was associated with a previous diagnosis of malignancy (risk ratio (RR) = 1.71; 95% CI, 1.09-2.68); mortality did not increase with increasing age. Of 163 individuals hospitalized at the time of gastrostomy, 42 (26%) were discharged home. Individuals with a previous diagnosis of stroke (RR = 2.80; 95% CI 1.01-7.77) were more likely to be discharged home than other individuals. CONCLUSIONS: Survival after percutaneous endoscopic gastrostomy is poor; the requirement for such a procedure appears to be a marker for severe underlying disease. The greater likelihood of return home after gastrostomy among individuals with stroke suggests that the use of this intervention as an adjunct to rehabilitation is appropriate in these individuals.

Risk of a new benzodiazepine prescription in relation to recent hospitalization.

OBJECTIVE: To determine if recent hospital admission was associated with new outpatient prescribing of benzodiazepines among community-dwelling older people. DESIGN: Nested case-control study using administrative data sets of the provincial health insurance board. SETTING: Province of Quebec. PARTICIPANTS: Cases were 4127 community-dwelling older people who were newly dispensed a benzodiazepine during an 8-month period in 1990. Controls were 16,486 community-dwelling older people who were dispensed any drug (except a benzodiazepine) on the same day as the case-defining index prescription. EXPOSURE AND OUTCOME MEASURES: Admission to an acute care hospital within a 30-day period before a new dispensing of a benzodiazepine. Other variables measured were patient age, gender, number of ambulatory physician visits, healthcare region, Chronic Disease Score (CDS), and use of drugs for depression and psychosis. RESULTS: Cases were more than three times as likely as controls to have been hospitalized in the 30-day period before the index date (adjusted odds ratio (OR) 3.09; 95% CI, 2.78-3.45). The use of prescription drugs for physical health problems modified this association in that cases who used more medication were also more likely to receive a new benzodiazepine prescription following a recent hospital admission (adjusted OR 4.09; 95% CI, 3.59-4.65 when the CDS was equal to 5 vs adjusted OR 1.96; 95% CI, 1.66-2.31 when the CDS was equal to 0). CONCLUSIONS: Recent hospitalization confers an increased risk of a new outpatient benzodiazepine prescription among community-dwelling older people in Quebec. Those who use more medication, and who may be more vulnerable to drug-related adverse events, are more likely to be newly dispensed a benzodiazepine following a recent, acute-care hospital admission.

Who should rate candidates in an objective structured clinical examination?

PURPOSE: To determine who is the better rater of history taking in an objective structured clinical examination (OSCE): a physician or a standardized patient (SP). METHOD: During the 1991 pilot administration of an OSCE for the Medical Council of Canada's qualifying examination, five history-taking stations were videotaped. Candidates at these stations were scored by three raters: a physician (MD), an SP observer (SPO), and an SP rating from recall (SPR). To determine the validity of each rater's scores, these scores were compared with a "gold standard", which was the average of videotape ratings by three physicians, each scoring independently. Analysis included both correlations with the standard and a repeated-measures analysis of variance (ANOVA) comparing raters' mean scores on each station with mean scores of the gold standard. RESULTS: Ninety-one videotapes were scored by the "gold-standard" physicians. Correlations with the standard showed no clear preference for MD, SPO, or SPR raters. ANOVAs revealed significant differences from the standard on three stations for the SPR, two stations for the SPO, and one stations for the MD. CONCLUSIONS: An MD rater is less likely to differ from a standard established by a consensus of MD ratings than are SP raters rating from recall. If an MD cannot be used, an SP observer is preferable to an SP rating from recall.

The impact of pharmacotherapy policy: a case study.

Universal drug insurance coverage has been endorsed by the National Health Forum and the Liberal government as a means of providing equitable access to prescription medication for Canadians. In 1996, Quebec legislated a universal drug insurance program. To finance extended coverage for approximately 1.2 million previously uninsured beneficiaries, an income-indexed coinsurance and deductible cost-sharing policy was introduced for previously insured beneficiaries (people 65 years of age and older, and those receiving income security allowance). The increase in cost-sharing for previously insured beneficiaries led to a reduction in both essential (senior citizens: 9.1%; income security: 14.4%) and less essential medication (senior citizens: 15.1%; income security: 22.4%). Reductions in the use of essential drugs were associated with an increase in the rate of emergency visits (by 43% in senior citizens and 78% in income security recipients) and adverse events (by over 100% in senior citizens and 88% in income security recipients). The 442 physicians and pharmacists who were surveyed reported that the policy reduced the use of antilipidemics, inhaled steroids and antihypertensives in the previously insured beneficiaries, but improved access to previously unaffordable medications for cardiac disease and asthma in the newly insured beneficiaries. Although universal drug insurance appeared to enhance access to essential medication for the newly insured, these benefits were exacted at a cost of producing unintended health effects in two vulnerable subgroups: senior citizens and income security recipients. Because no prior studies have shown that consumer cost sharing can lead to expected objective of selective reductions in less essential drug use alone, alternate policy approaches for financing universal drug coverage need to be considered.

Compliance and cognitive function: a methodological approach to measuring unintentional errors in medication compliance in the elderly. McGill-Calgary Drug Research Team.

This study describes the development of a method for assessing the relationship between cognitive function, comprehension, and compliance with medication. We assessed multiple aspects of cognitive performance, medication planning ability, and medication compliance in a convenience sample of 20 outpatients. Using a test battery that measured mental status, attention/concentration, memory function, and motor strength and dexterity, we found that: (1) standard mental status assessment was poorly correlated with memory function; (2) attention/concentration and memory were related to medication planning accuracy; (3) motor dexterity and strength were related to the ability to access medications; and (4) visual perception and memory were the skills most strongly correlated with medication compliance. Findings suggest that aspects of attention/concentration, visual and verbal memory, and motor function which are untapped by simple mental status assessment are related to medication access, planning, and compliance in elderly patients.

Coding accuracy of hospital discharge data for elderly survivors of myocardial infarction.

OBJECTIVE: To assess the coding accuracy of primary and secondary discharge diagnoses in the Quebec hospital discharge database for elderly persons with myocardial infarction (MI). DESIGN: Retrospective chart review in a convenience sample of six Montreal hospitals. The diagnoses listed in the medical chart were compared with those listed in the hospital discharge database. For each subject, the Charlson comorbidity index was calculated twice, once based on the medical chart and again based on the hospital discharge database. PATIENTS: Subjects aged 65 years and over who had an MI coded as the primary discharge diagnosis in the hospital discharge database and who were discharged alive. MAIN RESULTS: For 234 MI survivors, the positive predictive value (ie, probability that a patient with MI reported in the hospital discharge database had an MI diagnosed by the discharging physician) for coding MI was 0.96 (95% CI 0.94, 0.98). Comorbid medical conditions and complications of the MI were under-reported in the hospital discharge database, which meant that the Charlson index based on the hospital discharge database was an average of 0.71 units lower than the Charlson index based on the medical chart. CONCLUSIONS: When studying survivors of MI by using hospital discharge databases, the advantages must be weighed against potential drawbacks in the quality of the information. Hospital discharge databases are almost as reliable as medical charts for identifying MI patients, but there is substantial under-reporting of comorbid medical conditions.

Identifying subgroups of the general population that may be susceptible to short-term increases in particulate air pollution: a time-series study in Montreal, Quebec.

This study was undertaken in order to shed light on which groups of the general population may be susceptible to the effects of ambient particles. The objectives of the study were (1) to determine whether concentrations of particles in the ambient air of Montreal, Quebec, were associated with daily all-cause and cause-specific mortality in the period 1984 to 1993, and (2) to determine whether groups of the population had higher than average risks of death from exposure to particles. From the network of fixed-site air pollution monitors in Montreal we obtained daily mean levels of various measures of particles, gaseous pollutants, and weather variables measured at Dorval International Airport. We also used measurements of sulfate from an acid rain monitoring station 150 km southeast of the city (Sutton, Quebec). We estimated associations for particulate matter (PM) with an aerodynamic diameter of 10 microns or smaller (PM10), or 2.5 microns or smaller (PM2.5), total suspended particles (TSP), coefficient of haze (COH), an extinction coefficient, and sulfate. Because substantial data for fine particles were missing, we developed a regression model to predict PM2.5 and to predict sulfate from PM2.5. In the main body of the report, we present results for COH, predicted PM2.5, and sulfate. Detailed results for all pollutants are included in Appendices H through O, which are available on request from Health Effects Institute and from the HEI web site at www.healtheffects.org. To address the first objective, we made use of the underlying causes of death among all 140,939 residents of Montreal who died between 1984 and 1993. We regressed the logarithm of daily counts of cause-specific mortality on the daily mean levels for a variety of measures of particles, accounting for seasonal and subseasonal fluctuations in the mortality time series, overdispersion, and weather factors. To address the second objective, we developed algorithms to define conditions that subjects had prior to death, with the focus on cardiopulmonary diseases. These algorithms were based on information retained on the databases of the universal Quebec Health Insurance Plan (QHIP). The databases include records of all procedures (e.g., type of surgery), physician visits, and consultations carried out by all physicians in Quebec. For persons > or = 65 years and for all recipients of social assistance the prescription database contains records of all pharmaceuticals dispensed (type of medication, dose, quantity). For each group of conditions defined, we used the same statistical model that was used in the analyses of all nonaccidental causes of death. In the analyses of cause-specific mortality, we found evidence of associations for all nonaccidental causes of death and specific causes of death--cancer, coronary artery disease, respiratory diseases, and diabetes--that were consistent across most metrics of ambient air particle concentrations, evaluated as the 3-day mean of particle concentrations measured on the day of death (lag 0) and on each of the two days before death (lag 1, lag 2). Associations for all cardiovascular diseases combined were found only with sulfate. As well, we generally found increased daily mortality for persons 65 years of age and over. The results for all nonaccidental causes of death are similar to findings from other studies; the mean percent increase in mortality for a 100 micrograms/m3 increase in daily TSP at lag 0 was 6.7%. In the analyses of the groups defined from the QHIP data, there was little evidence of associations with air pollutants among persons who before death were classified as having acute or chronic upper respiratory diseases, airways diseases, hypertension, acute coronary artery diseases, and cerebrovascular diseases. On the other hand, we found consistent increases across most types of ambient particles for persons who had cancer, acute lower respiratory diseases, any form of cardiovascular disease, chronic coronary artery diseases, and congestive heart failure. As well, we found an association for individuals who did not have any cardiovascular disease, lower respiratory diseases, and cancer. This latter group consisted of persons who had no interactions with the health care system one year before death (12%) and individuals with a wide variety of potentially fatal diseases (52%), including neurological conditions (12%), diabetes (8%), cardiac dysrhythmias (8%), dementia (6%), organic psychotic disorders (6%), and anemias (4%). As statistical power was reduced in the analyses presented above, differences between groups (e.g., < 65 and > or = 65 year age groups) were not usually statistically significant. The association with diabetes has not been reported previously, and this needs to be replicated in other studies. (ABSTRACT TRUNCATED)

Is the public being protected? Prevention of suboptimal medical practice through training programs and credentialing examinations.

Governments have traditionally looked to the medical profession for leadership in health planning and have charged the profession with the responsibility of establishing and monitoring standards of medical practice. Training program accreditation and licensure/certification exams have been used as the primary methods of preventing unqualified individuals from entering medical practice. Despite the critical nature of the decision made at the time of licensure/certification, there is no information about the validity of these examinations for predicting subsequent practice and health outcome. In this article, the assumptions implicit in the current use of licensing/certifying examinations are identified, the relevant evidence is reviewed, and the implications of this evidence for current methods of measurement are discussed.

Characteristics of physicians who frequently prescribe long-acting benzodiazepines for the elderly.

Long-acting benzodiazepines (LABZs) are relatively contraindicated for elderly patients because they increase the risk of impaired cognitive function, falls, and hip fractures. The purpose of this study was to identify the characteristics of physicians who frequently prescribe LABZs for elderly patients. The authors examined the prescribing profile of 4,976 physicians who saw at least 20 elderly Quebec medicare registrants in 1990. Physicians who frequently prescribed LABZs for their elderly patients were more likely to have graduated before 1979, to be general practitioners as opposed to specialists, to practice in long-term care settings, and to have graduated from a medical school in Quebec as opposed to other schools in Quebec, in other provinces, or in other countries. The authors have identified several characteristics of physicians who frequently prescribed LABZs for the elderly. Strategies to improve prescribing in this field should target this group of physicians.

Medication use in seniors: challenges and solutions.

Use of prescribed and over-the-counter medication increases with age. Although drug therapy often results in beneficial effects and improve functional status, drug related illness is a significant health problem, accounting for 5 to 23 per cent of hospitalization, 1.75 per cent of ambulatory visits and one in 1000 deaths. In most studies, drug-related illness is more common in the elderly. Four factors influence the likelihood that a patient will experience adverse effects from a drug: the type of drug prescribed, the characteristics of patients receiving the drug, the characteristics of physicians who are prescribing the medication, and health care system policy and practice. Cardiovascular drugs, psychotropic drugs and NSAIDs are the three groups of drugs that are most commonly implicated in drug related illness, probably because they are the three groups of drugs that are most commonly prescribed in the elderly. The risk of an adverse effect with drug increases with the number of drugs prescribed. Several mechanisms may account for this phenomenon including (1) increased sensitivity of diseased tissue to drug toxicity (2) potential drug interactions, and (3) difficulties in patient compliance with an increasing number of drugs. Physician prescribing habits can increase the risk of adverse drug effects through two mechanisms: (1) the prescription of drugs that are unnecessary for the treatment of ailments that might be better managed through non-pharmacologic management and (2) the inappropriate prescription of drugs that are either contraindicated or prescribed in combination with other drugs that produce potential drug interaction. Errors in prescribing accounting for 19 to 36 per cent of hospital admissions due to drug-related events and up to 72 per cent of drug related events occurring in the hospital setting. Health care system policies influence the list of drugs that are included in the formulary, the conditions under which they are accessible and payment policy, all of which strongly influence the likelihood that a drug will be utilized. Physician payment policy may also influence drug prescribing and the success of initiatives to discontinue drugs. Interventions to improve the optimal use of medication will need to target policy, patients and physicians. Better information needs to be provided to physicians and patients about the risks and benefits of drug therapy, and the problems of patient compliance and inappropriate and unnecessary prescribing need to be addressed.

[Characteristics of physicians prescribing more psychotropic drugs to women than to men]. / Caractéristiques des médecins prescrivant des psychotropes davantage aux femmes qu'aux hommes.

In industrialized countries, gender differences observed in health condition and the use of medical services appear insufficient to explain a greater consumption of psychotropic drugs in women than men. The authors have tested the hypothesis that physician prescribing patterns largely explains this observation. They demonstrate, using data from the Régie de l'assurance maladie du Québec for people aged 65 and over, that physicians' sociodemographic and practice characteristics are significantly associated with the percentage of men and women who receive a psychotropic drug prescription in their practice.

Analysis of Centers for Disease Control and Prevention criteria for the eosinophilia-myalgia syndrome in a geographically defined population.

OBJECTIVE: To test whether individuals can be identified in a geographically defined population who would meet criteria for the eosinophilia-myalgia syndrome (EMS) established by the US Centers for Disease Control and Prevention (CDC), i.e, (1) eosinophil count > 1 x 10(9)/l, (2) myalgia severe enough to limit usual activities of daily living, and (3) no evidence of infection or neoplasm that could explain the first 2 findings. METHODS: To discover the number of individuals who would meet CDC criteria, the population was exhaustively searched using methods adapted from active pharmacoepidemiologic surveillance. Medical consultants and primary care practitioners were questioned as many as 5 times in a search for patients with severe myalgia. A predetermined protocol was used to screen those patients who appeared to meet CDC criteria for EMS using active surveillance methods. The study population was limited to Québec and Ontario (combined population 18,980,000) with special attention to the period July 1, 1992, to June 30, 1993. RESULTS: The prevalence of severe incapacitating myalgia was 43 per 100,000 persons, including 19 individuals with eosinophilia > 1 x 10(9)/l, who met CDC criteria for EMS. None of these individuals were reported to have taken L-tryptophan (LT). CONCLUSION: The CDC criteria for EMS are met by individuals in the general population who have never been exposed to LT.