Biomedical subjects

Adrian R Levy

Publications and source records attributed to Adrian R Levy.

At least 19 recordsLinked to original sources

PubMed2005

Chances of late surgery in relation to length of wait lists.

BACKGROUND: The proportion of patients who undergo surgery within a clinically safe time is an important performance indicator in health systems that use wait lists to manage access to care. However, little is known about chances of on-time surgery according to variations in existing demand. We sought to determine what proportion of patients have had late coronary bypass surgery after registration on wait lists of different size in a network of hospitals with uniform standards for timing of surgery. METHODS: Using records from a population-based registry, we studied wait-list times prospectively collected in a cohort of patients registered on wait lists for coronary artery bypass grafting procedures. We compared the number of weeks from registration to surgery against target access times established for three urgency groups. The chances of undergoing surgery within target time have been evaluated in relation to wait-list size at registration and the number of surgeries performed without registration on a wait list. RESULTS: In 1991-2001, two in three patients were at risk of late surgery when registered on wait lists for isolated coronary bypass procedures in British Columbia, Canada. Although urgent patients had never seen a wait list with clearance time exceeding one week, the odds of on-time surgery were reduced by 25%, odds ratio [OR] = 0.75 (95% confidence interval [CI] 0.65-0.87) for every additional operation performed without registration on a list. When the wait list at registration required a clearance time of over one month, semi-urgent patients had 51% lower odds of on-time surgery as compared to lists with clearance time less than one week, OR = 0.49 (95%CI 0.41-0.60), after adjustment for age, sex, comorbidity, calendar period, hospital and week on the list. In the non-urgent group, the odds were 69% lower, OR = 0.31 (95%CI 0.20-0.47). Every time an operation in the same hospital was performed without registration on a wait list, the odds of on-time surgery for listed patients were reduced by 7%, OR = 0.93 (95%CI 0.91-0.95) in the semi-urgent group, and by 10%, OR = 0.90 (95%CI 0.87-0.94), in the non-urgent group. CONCLUSION: Chances of late surgery increase with the wait-list size for semi-urgent and non-urgent patients needing coronary bypass surgery. The weekly number of patients who move immediately from angiography to the operation without registration on a wait list reduced chances of surgery within target time in all urgency groups of listed patients. When advising patients who will be placed on the wait list about the expected time to treatment, hospital managers should take into account the current list size as well as the weekly number of patients who require CABG immediately after undergoing coronary angiography.

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PubMed2005

Extending logistic regression to model diffuse interactions.

In an observational study focussed on association between a health outcome and numerous explanatory variables, the question of interactions can be problematic. Commonly, logistic regression of the outcome on the explanatory variables might be employed. Such modelling often includes an attempt to select some pairwise product interaction terms, from amongst the many such possible pairs. For several reasons, however, this can be unsatisfying. Here we consider a different approach based on a parsimonious extension of a logistic regression model without interaction terms. This extension permits an overall synergism or antagonism in how the explanatory variables combine to associate with the outcome, without any attempt to identify specific variables which give rise to interactive behaviour. We call this diffuse interaction. We elucidate some simple properties of the diffuse interaction model, and give an example of its application to epidemiological data. We also consider asymptotic behaviour in a restricted case of the model, to gain some insight into how well this kind of interaction can be detected from data.

Analysis of Variance↗

PubMed2005

Time on wait lists for coronary bypass surgery in British Columbia, Canada, 1991-2000.

BACKGROUND: In British Columbia, Canada, all necessary medical services are funded publicly. Concerned with growing wait lists in the mid-1990s, the provincial government started providing extra funding for coronary artery bypass grafting (CABG) operations annually. Although aimed at improving access, it is not known whether supplementary funding changed the time that patients spent on wait lists for CABG. We sought to determine whether the period of registration on wait lists had an effect on time to isolated CABG and whether the period effect was similar across priority groups. METHODS: Using records from a population-based registry, we studied the wait-list time before and after supplementary funding became available. We compared the number of weeks from registration to surgery for equal proportions of patients in synthetic cohorts defined by five registration periods in the 1990s. RESULTS: Overall, 9,231 patients spent a total of 137,126 person-weeks on the wait lists. The time to surgery increased by the middle of the decade, and decreased toward the end of the decade. Relative to the 1991-92 registration period, the conditional weekly probabilities of undergoing surgery were 30% lower among patients registered on the wait lists in 1995-96, hazard ratio (HR) = 0.70 (0.65-0.76), and 23% lower in 1997-98 patients, HR = 0.77 (0.71-0.83), while there were no differences with 1999-2000 patients, HR = 0.94 (0.88-1.02), after adjusting for priority group at registration, comorbidity, age and sex. We found that the effect of registration period was different across priority groups. CONCLUSION: Our results provide evidence that time to CABG shortened after supplementary funding was provided on an annual basis to tertiary care hospitals within a single publicly funded health system. One plausible explanation is that these hospitals had capacity to increase the number of operations. At the same time, the effect was not uniform across priority groups indicating that changes in clinical practice should be considered when adding extra funding to reduce wait lists.

Aged↗

PubMed2005

Changes in lipids over twelve months after initiating protease inhibitor therapy among persons treated for HIV/AIDS.

BACKGROUND: Protease inhibitors are known to alter the lipid profiles in subjects treated for HIV/AIDS. However, the magnitude of this effect on plasma lipoproteins and lipids has not been adequately quantified. OBJECTIVE: To estimate the changes in plasma lipoproteins and triglycerides occurring within 12 months of initiating PI-based antiretroviral therapy among HIV/AIDS afflicted subjects. METHODS: We included all antiretroviral naive HIV-infected persons treated at St-Paul's Hospital, British Columbia, Canada, who initiated therapy with protease inhibitor antiretroviral (ARV) drugs between August 1996 and January 2002 and who had at least one plasma lipid measurement. Longitudinal associations between medication use and plasma lipids were estimated using mixed effects models that accounted for repeated measures on the same subjects and were adjusted for age, sex, time dependent CD4+ T-cell count, and time dependent cumulative use of non-nucleoside reverse transcriptase inhibitors and adherence. The cumulative number of prescriptions filled for PIs was considered time dependent. We estimated the changes in the 12 months following any initiation of a PI based regimen. RESULTS: A total of 679 eligible subjects were dispensed nucleoside analogues and PI at the initiation of therapy. Over a median 47 months of follow-up (interquartile range (IQR): 29-62), subjects had a median of 3 (IQR: 1-6) blood lipid measurements. Twelve months after treatment initiation of PI use, there was an estimated 20% (95% confidence interval: 17% - 24%) increase in total cholesterol and 22% (12% - 33%) increase in triglycerides. CONCLUSIONS: Twelve months after treatment initiation with PIs, statistically significant increases in total cholesterol and triglycerides levels were observed in HIV-infected patients under conditions of standard treatment. Our results contribute to the growing body of evidence implicating PIs in the development of blood lipid abnormalities. In conjunction with the predominance or men, high rates of smoking, and aging of the treated HIV-positive population, elevated lipoproteins and triglycerides may mean that patients such as these are at elevated risk for cardiovascular events in the future.

Adult↗

PubMed2005

Economic evaluation of treating chronic obstructive pulmonary disease with inhaled corticosteroids and long-acting beta2-agonists in a health maintenance organization.

OBJECTIVES: In light of recent results from observational studies showing prolonged survival in subjects taking long-acting beta2-agonists (LABA) and/or inhaled corticosteroids (ICS) for chronic obstructive pulmonary disease (COPD), we investigated their cost-effectiveness (CE). METHODS: Costs and survival data were collected for a sample of members enrolled in a large Health Maintenance Organization in the United States. An observational study design was used to evaluate cumulative costs and health benefits of LABA, ICS, ICS+LABA, or comparison drugs. Survival was estimated using a parametric regression model. Costs were adjusted for censoring and prognostic factors. CE was evaluated over a time horizon of 36 months and the remaining lifetime of subjects. RESULTS: Over 36 months, life expectancy and costs were: 2.4 years (95% confidence interval (CI): 2.3; 2.5) and $28,030 (CI: $23,400; $33,570) for not receiving ICS or LABA; 2.6 years (CI: 2.6; 2.7) and $35,170 (CI: $29,970; $40,620) for ICS alone; 2.6 years (CI: 2.5; 2.7) and $27,380 (CI: $21,780; $32,510) for LABA alone; and, 2.7 years (CI: 2.6; 2.8) and $33,780 (CI: $28,700; $39,440) for subjects treated with ICS+LABA. The lifetime analysis showed similar trends. CONCLUSIONS: There is an acute need to find effective, life-extending treatments for persons with COPD. ICS, LABA or their combination represent promising treatment options and are currently being tested in randomized trials. If the impact on survival seen in these trials compares to that seen in observational studies, LABA and the combination treatment are likely to be cost-effective in the United States.

Administration, Inhalation↗

PubMed2005

The impact of reference pricing of nonsteroidal anti-inflammatory agents on the use and costs of analgesic drugs.

OBJECTIVE: To estimate the effect of reference pricing (RP) of nonsteroidal anti-inflammatory drugs (NSAIDs) on drug subsidy program and beneficiary expenditures on analgesic drugs. DATA SOURCES/STUDY SETTING: Monthly claims data from Pharmacare, the public drug subsidy program for seniors in British Columbia, Canada, over the period of February 1993 to June 2001. STUDY DESIGN: RP limits drug plan reimbursement of interchangeable medicines to a reference price, which is typically equal to the price of the lowest cost interchangeable drug; any cost above that is borne by the patient. Pharmacare introduced two different forms of RP to the NSAIDs, Type 1 in April 1994 and Type 2 in November 1995. Under Type 1 RP, generic and brand versions of the same NSAID are considered interchangeable, whereas under Type 2 RP different NSAIDs are considered interchangeable. We extrapolated average reimbursement per day of NSAID therapy over the months before RP to estimate what expenditures would have been without the policies. These counterfactual predictions were compared with actual values to estimate the impact of the policies; the estimated impacts on reimbursement rates were multiplied by the postpolicy volume of NSAIDS dispensed, which appeared unaffected by the policies, to estimate expenditure changes. PRINCIPAL FINDINGS: After Type 2 RP, program expenditures declined by $22.7 million (CAN), or $4 million (CAN), annually cutting expenditure by about half. Most savings accrued from the substitution of low-cost NSAIDs for more costly alternatives. About 20 percent of savings represented expenditures by seniors who elected to pay for partially reimbursed drugs. Type 1 RP produced one-quarter the savings of type 2 RP. CONCLUSIONS: Type 2 RP of NSAIDs achieved its goal of reducing drug expenditures and was more effective than Type 1 RP. The effects of RP on patient health and associated health care costs remain to be investigated.

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PubMed2004

Cost-effectiveness of rhythm versus rate control in atrial fibrillation.

BACKGROUND: Atrial fibrillation is the most common type of sustained cardiac arrhythmia, but recent trials have identified no clear advantage of rhythm control over rate control. Consequently, economic factors often play a role in guiding treatment selection. OBJECTIVE: To estimate the cost-effectiveness of rhythm-control versus rate-control strategies for atrial fibrillation in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM). DESIGN: Retrospective economic evaluation. Nonparametric bootstrapping was used to estimate the distribution of incremental costs and effects on the cost-effectiveness plane. DATA SOURCES: Data on survival and use of health care resources were obtained for all 4060 AFFIRM participants. Unit costs were estimated from various U.S. databases. TARGET POPULATION: Patients with atrial fibrillation who were 65 years of age or who had other risk factors for stroke or death, similar to those enrolled in AFFIRM. TIME HORIZON: Mean follow-up of 3.5 years. PERSPECTIVE: Third-party payer. INTERVENTIONS: Management of patients with atrial fibrillation with antiarrhythmic drugs (rhythm control) compared with drugs that control heart rate (rate control). OUTCOME MEASURES: Mean survival, resource use, costs, and cost-effectiveness. RESULTS OF BASE-CASE ANALYSIS: A mean survival gain of 0.08 year (P = 0.10) was observed for rate control. Patients in the rate-control group used fewer resources (hospital days, pacemaker procedures, cardioversions, and short-stay and emergency department visits). Rate control costs 5077 dollars less per person than rhythm control. RESULTS OF SENSITIVITY ANALYSIS: Cost savings ranged from 2189 dollars o 5481 dollars per person. Rhythm control was more costly and less effective than rate control in 95% of the bootstrap replicates over a wide range of cost assumptions. LIMITATIONS: Resource use was limited to key items collected in AFFIRM, and the results are generalizable only to similar patient populations with atrial fibrillation. CONCLUSION: Rate control is a cost-effective approach to the management of atrial fibrillation compared with maintenance of sinus rhythm in patients with atrial fibrillation similar to those enrolled in AFFIRM.

Anti-Arrhythmia Agents↗

PubMed2004

Self-reported Morisky score for identifying nonadherence with cardiovascular medications.

BACKGROUND: The Morisky medication adherence scale is a commonly used adherence screening tool. It is composed of 4 yes/no questions about past medication use patterns and is thus quick and simple to use during drug history interviews. OBJECTIVE: To evaluate the use of the self-reported Morisky score as a screening tool for identifying patients who have been nonadherent with chronic cardiovascular medications. METHODS: Patients who had taken an angiotensin-converting enzyme inhibitor or lipid-lowering agent for at least 3 consecutive months were interviewed using a structured questionnaire including the Morisky scale. Nonadherence was defined as taking < 80% of chronic cardiovascular medications based on prescription refill data over the previous 14 months. RESULTS: Forty-nine of 377 (13%) patients were categorized as nonadherent; however, only 12 (3%) patients had Morisky scores suggesting a high likelihood of nonadherence (3 or 4). While the Morisky score was a significant independent predictor of nonadherence by multivariate analysis, there was no threshold score or individual question that yielded concurrent high sensitivity and positive predictive values (PPVs) for identifying nonadherent patients. The internal consistency of the questions was low (alpha 0.32), as were item-to-total score correlations, suggesting that the individual questions were not measuring the same attribute. CONCLUSIONS: Using the Morisky scale to identify patients who have been nonadherent with chronic cardiovascular medications may be reasonable in some settings; however, the threshold score would have to be chosen based on a trade-off between sensitivity and PPV. These results were likely influenced by the low rate of nonadherence in this cohort. Rewording the questions, increasing the number of questions, and the use of graded response options may improve consistency.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2004

Antiretroviral resistance among HIV-infected persons who have died in British Columbia, in the era of modern antiretroviral therapy.

BACKGROUND: The prevalence of antiretroviral resistance among persons enrolled in the centralized HIV/AIDS Drug Treatment Program in British Columbia, Canada, who had died between July 1997 and December 2001, was investigated, to determine the degree to which antiretroviral resistance contributed to mortality. METHODS: During this period, 637 deaths had occurred. The last plasma sample obtained during therapy was genotyped retrospectively for treated individuals who had died of a nonaccidental cause. Samples with plasma human immunodeficiency virus (HIV) loads <500 copies/mL were not genotyped. Drug resistance among 1220 living HIV-infected persons who had experienced virologic therapy failure during the study period also was examined. RESULTS: Of 554 individuals who had died of nonaccidental causes, 58 (10.4%) were antiretroviral naive, and 99 (17.9%) had very brief exposure to antiretroviral therapy (median, 2 months). The majority of isolates from the remaining 397 individuals harbored either no major resistance mutations or represented samples with plasma HIV suppression of <500 copies/mL. Resistance to >/=1, >/=2, or 3 drug classes was observed in 76%, 42%, and 11% of individuals, respectively, in the group of 1220 living individuals experiencing virologic therapy failure, compared with only 44%, 23%, and 5% of individuals, respectively, who had died (P<.001). CONCLUSION: Only a relatively low prevalence of multidrug resistance was observed in this cohort, indicating that the exhaustion of treatment options because of drug resistance was not a significant contributor to mortality.

Adult↗

PubMed2004

Use of time-dependent measures to estimate benefits of beta-blockers after myocardial infarction.

PURPOSE: To estimate the reduction in all-cause mortality conferred by beta-blockers in a population-based cohort of elderly survivors of myocardial infarction during the year following hospital discharge. METHODS: A dynamic retrospective cohort was assembled from persons aged 66 years and over surviving myocardial infarction in Quebec between 1990 and 1993. Information on hospitalizations was linked to medication and physician claims, demographic characteristics and vital status. Subjects prescribed beta-blockers at hospital discharge had fewer comorbid medical conditions, less pre-existing cardiovascular disease and less severe infarcts. To control for these differences, analyzes were restricted to subjects receiving at least one beta-blocker and mortality was compared between periods with and without beta-blocker exposure using Cox proportional hazard models. RESULTS: Among 14,547 survivors of myocardial infarction, 41% were dispensed at least one beta-blocker. Among those subjects, the risk of dying during periods of beta-blocker use was reduced 40% (hazard ratio = 0.6; 95% CI: 0.5, 0.7). CONCLUSION: Confounding by indication threatens the validity of observational studies of intended effects of medications. For elderly survivors of myocardial infarction, the estimated benefit of beta-blockers from observational studies is greater than the estimate from randomized trials. Greater benefits do not seem to be an artifact arising from systematically prescribing beta-blockers to subjects with better prognosis. Reducing confounding by indication can enhance the validity of observational studies of medications and widen research applications of administrative health databases. While the actual benefits of medications are never truly known these studies can provide a credible range that brackets the truth.

Adrenergic beta-Antagonists↗

PubMed2003

Interventional cardiovascular procedures among HIV-infected individuals on antiretroviral therapy 1995-2000.

OBJECTIVE: To calculate the rate of interventional cardiac procedures (ICP) among HIV-infected individuals ever treated with antiretroviral therapy (ART) and to describe clinical and sociodemographic characteristics associated with ICP. METHODS: Since 1992, ART in British Columbia (BC) has been centrally distributed by the BC Centre for Excellence in HIV/AIDS. The BC Cardiac Registry maintains information regarding all cardiac procedures performed in BC. The two databases were linked to determine the number of HIV-positive individuals on ART who underwent ICP. Age-adjusted analyses were conducted using direct standardization, and linear regression to test for trend over time. Logistic regression was used to identify patient and treatment characteristics independently associated with having an interventional cardiac procedure. RESULTS: Of the 5082 individuals who have ever received ART, 63 (< 1%) were captured in the Cardiac Registry. There were 97 events: 70 (72%) since 1999. The age-adjusted event rate per 1000 HIV-positive individuals on ART increased significantly over time (P = 0.015) whereas that for the general BC population did not increase over time (P = 0.191). In multivariate analysis, age at baseline per 10 year increase [adjusted odds ratio (AOR) 2.5; 95% confidence interval (CI), 1.8-3.2), and months on ART (AOR 1.3; 95% CI, 1.1-1.4) remained significant. CONCLUSIONS: The rate of ICP among HIV-positive individuals on ART appears to be increasing; in addition, the duration of time on ART is independently associated with ICP after adjustment for patient demographic characteristics.

Adult↗

PubMed2003

A simple approach to fitting Bayesian survival models.

There has been much recent work on Bayesian approaches to survival analysis, incorporating features such as flexible baseline hazards, time-dependent covariate effects, and random effects. Some of the proposed methods are quite complicated to implement, and we argue that as good or better results can be obtained via simpler methods. In particular, the normal approximation to the log-gamma distribution yields easy and efficient computational methods in the face of simple multivariate normal priors for baseline log-hazards and time-dependent covariate effects. While the basic method applies to piecewise-constant hazards and covariate effects, it is easy to apply importance sampling to consider smoother functions.

Bayes Theorem↗

PubMed2003

Rapid increase in statins newly dispensed to Ontario seniors between 1994 and 2000.

BACKGROUND: The Ontario government spent approximately 10% (CDN $148 million) of the provincial medication budget on statins in 1998. This number can be expected to grow in light of new guidelines from the United States recommending that three times as many patients should be receiving antihyperlipidemic therapy. There is scant population-based information on the age and sex distributions of patients receiving these medications. OBJECTIVES: To estimate the rates of new use of statin medications among community-dwelling elderly adults in Ontario between 1994 and 2000. METHODS: Data from the Ontario Drug Benefit program were used on all medications dispensed to noninstitutionalized Ontarians over 65 years of age to estimate age- and sex-specific annual rates of patients newly dispensed a statin. Changes in rates were estimated using Poisson regression. RESULTS: The number of elderly Ontarians newly dispensed a statin increased rapidly between 1994 and 2000, with age-standardized rates rising from approximately 840 to 2600/100,000 women and from 810 to about 3100/100,000 men. The highest rates of new use were observed among patients of both sexes aged 65 to 74 years. However, the rate of change increased with advancing age so that the biggest increase was observed among those aged 85 years and above, among whom there was an 8.5-fold increase among women and a 12-fold increase among men. CONCLUSIONS: Statins have been shown to be safe, efficacious and cost effective in reducing the risk of sudden cardiac death and other acute coronary events among middle-aged patients with pre-existing cardiovascular disease. The present study showed that there was a rapid increase in the rate of statins newly dispensed to elderly patients in Ontario, among whom estimates of safety, efficacy and cost effectiveness are not well quantified. Better estimates of these parameters in the elderly are required because of the high costs and benefits and potential unintended beneficial and harmful effects of statins.

Aged↗

PubMed2003

Coding accuracy of administrative drug claims in the Ontario Drug Benefit database.

BACKGROUND: Every year in Ontario, the records of over 42 million prescriptions dispensed to persons eligible for Ontario Drug Benefit (ODB) benefits are transmitted to a central database. The ODB database is the second largest database of medications in Canada, containing records on almost half of all medications dispensed in Ontario. There is no information about the reliability of the coding on the ODB drug claims database and, therefore, the objective of this study was to estimate the reliability of coding of the Drug Identification Number, and the date, quantity and duration of the dispensation on claims sent to the ODB. METHODS: To meet this objective, approximately 100 randomly selected prescriptions dispensed from each of 50 pharmacies in southern Ontario between July 1, 1998 and December 31, 1999 were audited. For each claim, the written information on the prescription was compared with the electronic information submitted to the ODB database. Logistic regression was used to test the association between coding errors and the location, owner affiliation, and productivity of each pharmacy (defined as the annual volume of dispensations divided by the annual number of hours worked by all pharmacists and pharmacy assistants). RESULTS: Of the 183 pharmacies owners invited to participate, consent to abstract information was obtained in 50, yielding a participation rate of 27%. Of the 5155 dispensed prescriptions, 37 errors were found, yielding an overall error rate of 0.7% (95% CI 0.5% to 0.9%). None of the characteristics of pharmacies that were examined (location, owner affiliation, productivity) was associated with coding errors. CONCLUSIONS: Pharmacists almost always dispense the medication that is prescribed and this information is reliably transmitted to the ODB drug claims database. This means that any conclusions drawn by researchers using these data are not likely to be compromised by low coding reliability.

Clinical Pharmacy Information Systems↗

PubMed2002

Impact of reference-based pricing for histamine-2 receptor antagonists and restricted access for proton pump inhibitors in British Columbia.

BACKGROUND: Two programs to reduce expenditures for common gastrointestinal drugs were introduced simultaneously by British Columbia (BC) Pharmacare in 1995. Reference-based pricing restricted reimbursement for all histamine-2 receptor antagonists (H2RAs) to the cost of the least expensive H2RA available, generic cimetidine. Special authority restricted reimbursement for proton pump inhibitors (PPIs) to patients who met certain eligibility criteria. We evaluated the effect of reference-based pricing for H2RAs and special authority for PPIs on dispensing and reimbursement for senior citizen beneficiaries of BC Pharmacare. METHODS: Itemized monthly claims data for upper gastrointestinal drugs were obtained from BC Pharmacare for all beneficiaries 65 years of age or older. Periods before and after implementation of reference-based pricing and special authority were compared with respect to defined daily doses dispensed per 100,000 beneficiaries, BC Pharmacare reimbursement per 100,000 beneficiaries, BC Pharmacare reimbursement per defined daily dose and beneficiary contributions per defined daily dose. We used regression models to project forward trends in expenditures observed before implementation of the new policies and hence to estimate accrued cost savings. RESULTS: Before reference-based pricing and special authority, the numbers of defined daily doses that were dispensed and total BC Pharmacare reimbursements for H2RAs appeared to be declining gradually, whereas those for PPIs were rising. With reference-based pricing, the monthly defined daily dose of cimetidine dispensed increased more than 4-fold, to 116,257 per 100,000 beneficiaries, while those of other restricted H2RAs decreased by more than half, to 50,927 per 100,000 beneficiaries. Special authority immediately reduced the dispensed volumes of PPIs by one-fourth, but growth in volume then appeared to resume at its previous rate. The estimated annualized cost savings achieved by reference-based pricing and special authority were $1.8 million to $3.2 million for H2RAs (depending on the estimation method used) and $5.5 million for PPIs. However, beneficiary contributions for H2RAs increased from negligible amounts to approximately 16% of total drug expenditures. INTERPRETATION: Reference-based pricing and special authority appear to have been successful in altering prescribing habits and reducing provincial expenditures for upper gastrointestinal drugs, but they have increased the financial burden on senior citizen beneficiaries.

Aged↗

PubMed2002

The effect of physicians' training on prescribing beta-blockers for secondary prevention of myocardial infarction in the elderly.

PURPOSE: The objective was to determine whether the year and medical school of graduation, the medical specialty and the sex of the treating physician was associated with prescribing beta-blockers after hospital discharge among survivors of myocardial infarction (MI), after adjusting for patient characteristics. METHODS: We carried out a dynamic retrospective cohort study using data from a longitudinal database that contained information on Quebec residents over the age of 65 years sent home from hospital after MI between 1990 and 1993. The outcome was a beta-blocker being dispensed after hospital discharge. Logistic regression was used to estimate the association between training characteristics and beta-blocker dispensation and clustering of patients within physicians was accounted for using Generalized Estimating Equations. RESULTS: The cohort consisted of 14,334 MI survivors who were treated by 3209 physicians, yielding a mean of about 4.5 patients per physician [standard deviation (SD) = 8.2]. Beta-blockers were prescribed to approximately one-third of subjects. After adjusting for patients' demographic characteristics, comorbid medical conditions, and markers of MI severity, physicians who were more likely to prescribe a beta-blocker included cardiologists and the most recent graduates (graduating after 1989). Systematic differences were also observed between graduates of different medical schools. CONCLUSIONS: After adjusting for differences between patients', the sex of the physician was largely unrelated to prescribing beta-blockers for secondary prevention of MI. However, prescribing differed by training characteristics such as medical specialty and year and medical school of graduation.

Adrenergic beta-Antagonists↗

PubMed2002

Getting the cat back in the bag: reforming the way provinces manage drug expenditures to make them manageable.

The fiscal "cat" of healthcare spending - drug expenditures - is out of the bag: drug costs are now the fastest rising component of healthcare expenditures in Canada. Laupacis, Anderson and O'Brien describe the current process of listing drugs on the provincial drug formulary in Ontario, identify factors that may contribute to the rapid growth in drug expenditures, and make a number of recommendations for controlling drug expenditures, including (1) improving the evidence on cost-effectiveness; (2) disseminating the evidence to prescribers; (3) re-evaluating the evidence; and (4) increasing the transparency about the acquisition costs of drugs. These are recommendations that, if implemented, would theoretically help decision-makers make more rational decisions about which drugs to list on provincial formularies. The question of how to implement the recommendations remains to be elucidated, as does an evaluation of the trade-offs between costs and benefits of obtaining better information on cost-effectiveness.

Canada↗

PubMed2002

Effect of number of medications on cardiovascular therapy adherence.

OBJECTIVE: Increasing regimen complexity is generally assumed to result in lower medication adherence, but there is conflicting evidence. This study determined the relationship between the number of medications dispensed and adherence with chronic cardiovascular regimens. METHODS: A survey was administered to 367 patients who had taken an angiotensin-converting enzyme inhibitor or lipid-lowering medication for at least 3 consecutive months. Information was collected on nonprescription drug use, demographics, adverse effects, and use of adherence aids. Prescription drug use data over the previous 12 months were obtained for each subject from the British Columbia prescription claims database. Adherence for each prescription medication was calculated based on prescription fill dates and number of days supplied. Univariate and multivariate analyses were used to identify predictors of nonadherence (<80%) with cardiovascular medications. RESULTS: Forty-five subjects (12%) were categorized as nonadherent. Nonadherent subjects took fewer regularly scheduled prescription medications per day (4.1 +/- 2.7 vs. 5.9 +/- 3.4; p = 0.001), fewer pills per day (5.3 +/- 3.6 vs. 9.2 +/- 7.1; p < 0.001), and had fewer administration times per day (1.8 +/- 0.7 vs. 2.4 +/- 0.9; p = 0.001). A multivariate logistic regression model adjusting for age, gender, reported adverse effects, reported nonprescription drug use, and use of adherence aids identified fewer regularly scheduled prescription drugs as an independent predictor of nonadherence with chronic cardiovascular medications (OR = 0.85 per medication, 95% CI 0.74 to 0.94; p = 0.01). CONCLUSIONS: Contrary to popular belief, taking fewer medications was associated with lower adherence with chronic cardiovascular regimens.

Aged↗