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J Hallas

Publications and source records attributed to J Hallas.

At least 19 recordsLinked to original sources
PubMed2000

[Big differences in the frequency of polypharmacy between physicians].

Polypharmacy, the simultaneous use of multiple drugs, is associated with adverse drug reactions, medication errors, and increased risk of hospitalisation. When the number of drugs is five or more (major polypharmacy), a significant risk may be present. We analysed the prevalence of major polypharmacy among listed patients, and identified possible predictors of major polypharmacy related to the practice. Prescription data were retrieved from the Odense Pharmaco-epidemiological Database and the age and sex standardised prevalence rate of major polypharmacy was calculated for each practice (n = 173). Possible predictors of major polypharmacy related to the GPs were analysed by backward stepwise linear multiple regression. A six-fold variation between practices in the prevalence of major polypharmacy was found, i.e. from 16 to 96 per 1000 listed patients (median: 42). Predictors related to the practice structure, workload, clinical work profile, and prescribing profile could explain 56% of the variation.

Adult↗
PubMed2000

Pharmacovigilance based on prescription databases.

Prescription databases are indispensible in drug safety research and surveillance. For suspected rare serious adverse drug reactions, the confirmation and quantitative risk assessment requires proper epidemiological studies. Often prescription databases provide the information on drug exposure for such studies. Aberrant drug utilization in terms of overuse, underuse, polypharmacy etc. may be a threat to the health of the patient, and these aspects can best be studied by prescription databases. In cases of international drug safety alerts, prescription databases may provide information required for rational actions to be taken.

Aged↗
PubMed2000

Drug-induced symptoms of functional dyspepsia and nausea. A symmetry analysis of one million prescriptions.

BACKGROUND: A large variety of drugs have been implicated in causing dyspepsia. Due to the high background incidence of dyspepsia it is impossible to distinguish between spontaneous and truly drug-related symptoms. Most patients with dyspeptic symptoms are treated empirically. Drug-induced dyspepsia might therefore be reflected in the sequencing of prokinetics relative to other medications. AIM: To screen a large prescription database for signs of drug-induced functional dyspepsia, applying a symmetry principle. METHODS: Prescription data on all incident users of cisapride and metoclopramide were used to identify individuals who had started their first therapies with a prokinetic drug and an index drug within a 100-day span. A dyspepsia-provoking effect of the index drug would manifest as an excess of persons with the prokinetic drug prescribed last in this selected population. Relative to conventional analyses based on case-control or cohort design, this principle is robust to confounders that are stable over time. RESULTS: In the cisapride analysis (1825 persons) no single drug had adjusted rate ratios significantly above unity. An inverse signal for antidepressants (rate ratio 0.57; 95% CI: 0.39-0.84) suggests that these drugs may have a therapeutic effect against functional dyspepsia. In the metoclopramide analysis (6126 persons) positive signals were found for 14 drugs, all well-known for causing nausea as a side-effect, with the exception of insulin (rate ratio 2.91, 95% CI: 1.40-8.11). CONCLUSIONS: Drug-induced symptoms of functional dyspepsia are rare and do not contribute to the use of cisapride. The start of insulin treatment may induce nausea.

Adult↗
PubMed1999

[National surveillance of Helicobacter pylori eradication in Denmark. Results based on registration of 34.582 drug prescriptions].

We wanted to characterize the use of H. pylori eradication therapy in Denmark (inhabitants 5,227,862). All H. pylori eradication treatments from a nation wide database covering all drug prescriptions in the period January 1994-June 1996 were identified. We found 28,784 out-patients having a prescription with drugs for H. pylori eradication, accounting for 34,582 prescriptions in total. The incidence of new consumers was 220 per 10(5) inhabitants per year, with a maximum at 70-79 years of age. Eighty-six percent of the patients had only one treatment course. Forty-five percent had an anti-ulcer drug prescribed 1-12 months after the H. pylori eradication therapy. Consumption of antibiotics used for H. pylori eradication accounted for 1.4% of the total consumption of antibiotics. In conclusion, the incidence of H. pylori eradication therapy was fairly stable but with changes in the pattern of drug regimens used. Anti-ulcer drugs were often given after H. pylori eradication therapy, suggesting an inappropriate use of eradication treatment.

Adult↗
PubMed1999

[Polypharmacy estimated by means of a population-based prescription database].

The aim was to investigate estimators of polypharmacy (PP) from a population based prescription database. Data were retrieved from Odense Pharmacoepidemiological Database and contained a 10% random sample (n = 26,977) of drug users in 1994. PP was defined as simultaneous treatment with different drugs, and the duration of treatment was calculated from the date of purchase and the number of defined daily doses prescribed. This estimator was compared with an estimator based on the number of drugs purchased during a three month period. On an average day 8.7% were exposed to minor PP (two to four drugs) and 1.2% to major PP (five or more drugs). Purchase of five or more drugs during a three month period predicted episodes of major PP with a positive predictive value of 80%. Epidemiological measures of multiple drug use can be estimated from a prescription database. Conceptually, an estimator based on the number of simultaneously used drugs is preferable, but the number of drugs purchased during a three month period may be a useful alternative estimator.

Databases, Factual↗
PubMed1999

Helicobacter pylori and risk of ulcer bleeding among users of nonsteroidal anti-inflammatory drugs: a case-control study.

BACKGROUND & AIMS: Peptic ulcer complications related to use of nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most common serious adverse drug reactions. Whether Helicobacter pylori infection potentiates this gastrointestinal toxicity of NSAIDs is still unresolved. In this study, we investigated the role of H. pylori as a cause of bleeding peptic ulcer among NSAID users. METHODS: A case-control study of current users (n = 132) of NSAIDs (including acetylsalicylic acid), admitted because of bleeding peptic ulcer, was performed. Controls were 136 NSAID users without gastrointestinal complications. H. pylori was diagnosed by either increased levels of serum immunoglobulin G or by 13C-urea breath test. RESULTS: Fifty-eight (44%) case subjects had a bleeding gastric ulcer, 54 (41%) had a bleeding duodenal ulcer, 12 (9%) had both gastric and duodenal ulcers, and 8 (6%) had hemorrhagic gastritis. H. pylori was present in 75 (57%) cases compared with 59 (43%) controls. The adjusted odds ratio of bleeding peptic ulcer among NSAID users associated with H. pylori infection was 1.81 (95% confidence interval, 1.02-3.21). H. pylori accounted for approximately 24% of bleeding peptic ulcers among elderly NSAID users. CONCLUSIONS: NSAID users infected with H. pylori have an almost twofold increased risk of bleeding peptic ulcer compared with NSAID users without H. pylori.

Adult↗
PubMed1999

Polypharmacy in general practice: differences between practitioners.

BACKGROUND: Polypharmacy, the simultaneous use of multiple drugs, is associated with adverse drug reactions, medication errors, and increased risk of hospitalization. When the number of concurrently used drugs totals five or more (major polypharmacy), a significant risk may be present. AIM: To analyse the interpractice variation in the prevalence of major polypharmacy among listed patients, and to identify possible predictors of major polypharmacy related to the practice. METHOD: Prescription data were retrieved from the Odense Pharmacoepidemiological Database, and individuals subject to major polypharmacy were identified. The age- and sex-standardized prevalence rate of major polypharmacy was calculated for each practice in the County of Funen in Denmark (n = 173), using the distribution of age and sex of the background population as a reference. The practice characteristics were retrieved from the Regional Health Insurance System. Possible predictors of major polypharmacy related to the general practitioners (GPs) were analysed using backward stepwise linear multiple regression. RESULTS: A six-fold variation between the practices in the prevalence of major polypharmacy was found (16 to 96 per 1000 listed patients; median = 42). Predictors related to the practice structure, workload, clinical work profile, and prescribing profile could explain 56% of the variation. CONCLUSION: A substantial part of the variation in major polypharmacy between practices can be explained by predictors related to practice.

Adult↗
PubMed1998

[Antabus treatment in general practice. A pharmaco-epidemiological study of prescription patterns based on a prescription database].

Denmark has a long tradition for the use of alcohol-aversive drugs in the treatment of alcoholism, most commonly disulfiram (Antabuse). The purpose of this study was to examine the prescription patterns for disulfiram in Danish general practice on an individual level. By means of a prescription database we analysed 150,787 prescriptions on reimbursed medicine to persons who had redeemed prescriptions for alcohol-aversive drugs during the period 1.1.1993 to 31.12.1995 in the County of Funen. Prevalence of disulfiram treatment was 12 per 10,000 inhabitants, three-year prevalence 75 per 10,000 inhabitants and incidence 21 per 10,000 inhabitants per year. Eighty-seven percent of treatments were stopped at (or before) the expiration of one prescription, and relapse was frequent (46%).

Adult↗
PubMed1998

Polypharmacy: correlations with sex, age and drug regimen. A prescription database study.

OBJECTIVE: To analyse the occurrence of multiple drug use (polypharmacy, PP) in the population and to identify individuals particularly prone to PP. METHODS: Data were derived from the Odense Pharmacoepidemiological Database (OPED) and covered all subsidised prescriptions during 1994 presented by inhabitants in the county of Funen (n = 466567). The number of individuals concurrently using two to four drugs (minor PP) and five or more drugs (major PP) was calculated on a random day in 1994. Drugs were classified according to the Anatomical Therapeutical Chemical (ATC) classification index. The main therapeutic class (second level of the ATC code) was used as an indicator for the type of health problem. A stepwise backwards logistic regression was used to identify predictors of major PP. Odds ratios were calculated for different drug classes, and the age and sex of all drug users. RESULTS: On a random day, 8.3% of the population were exposed to minor PP and 1.2% to major PP. The prevalence of PP increased with age, and from the age of 70 years, two thirds of all drug users were PP users. Drug use was 50% more prevalent among women than men, but over the age of 70, the sexes did not differ in the prevalence of major PP. Many different drug combinations were found, and among major PP users (n = 5443), two thirds had their own unique drug regimen, different from all other drug users. Cardiovascular drugs and analgesics were often involved in PP among the elderly, while asthma drugs, psychotropic drugs and anti-ulcer drugs were predominant among young individuals exposed to PP. The odds ratio (OR) for major PP was substantially increased for individuals treated for cardiovascular diseases (OR, 4.5), anaemia (OR, 4.1) and respiratory diseases (OR, 3.6). CONCLUSIONS: PP is widespread in the population. Clinicians and organisers who are responsible for quality assurance programmes should intensify their surveillance of the groups most prone to PP (the elderly and those using analgesics or drugs for cardiovascular disease, anaemia, asthma and diabetes).

Adolescent↗
PubMed1998

National surveillance of Helicobacter pylori eradication therapy in Denmark. Results from registration of 34,582 prescriptions.

BACKGROUND: We wanted to characterize the use of Helicobacter pylori eradication therapy in Denmark (5,227,862 inhabitants). METHODS: All H. pylori eradication treatments from a nationwide database including all redeemed drug prescriptions in the period January 1994 to June 1996 were identified. So were all outpatients receiving a drug prescription for H. pylori eradication. RESULTS: We recorded 34,582 prescriptions for H. pylori eradication therapy given to 28,784 patients. The incidence of new consumers was 220 per 10(5) inhabitants per year, with a maximum at 70-79 years of age. Eighty-six per cent of the patients had only one treatment course. In 16% of the eradication therapies, nonsteroid anti-inflammatory drugs had been prescribed within the previous 3 months, and 45% had an anti-ulcer drug prescribed 1-12 months after the H. pylori eradication therapy. Consumption of antibiotics used for H. pylori eradication accounted for 1.4% of the total consumption of antibiotics. CONCLUSIONS: The incidence of H. pylori eradication therapy was fairly stable but with changes in the pattern of drug regimens used. Anti-ulcer drugs were often given after H. pylori eradication therapy, suggesting an inappropriate use of treatment.

Adolescent↗
PubMed1998

Screening for drug related dyspepsia: an analysis of prescription symmetry.

OBJECTIVE: Most patients with severe upper dyspepsia are treated empirically with ulcer drugs. Drug-induced dyspepsia might therefore be reflected in the sequencing of ulcer drugs relative to other medications. Our aim was to screen a large population-base prescription database for evidence of drug-induced dyspepsia. METHODS: Prescription data on 31,232 incident users of ulcer drugs were drawn from a research database, covering the county of Funen, Denmark. We identified all individuals who had started their first recorded therapies with an ulcer drug and another non-ulcer drug within a 100 day span. In this selected group, there would normally be an equal number starting either drug first, while a dyspepsia-provoking effect of the non-ulcer drug would manifest as an excess of individuals with the ulcer drug prescribed last. This screening method is robust to confounders that are stable over time. RESULTS: Only non-steroidal antiinflammatory drugs (adjusted rate ratio (RR) 1.8, 95% confidence interval (CI), 1.6-2.0), calcium blockers (RR 1.4, CI 1.2-1.7), corticosteroids (RR 1.1, CI 1.0-1.3), angiotensin converting enzyme inhibitors (RR 1.4, CI 1.1-1.7) and methylxanthines (RR 1.5, CI 1.1-2.2) showed a significant asymmetry suggesting a dyspepsia-provoking effect. An analysis of effect modifiers suggested that the signals for corticosteroids and for angiotensin converting enzyme inhibitors were explained by concurrent use of non-steroidal anti-inflammatory drugs and by underlying congestive heart failure. The signal for non-steroidal anti-inflammatory drugs may be explained by the known reputation of non-steroidal antiinflammatory drugs for causing ulcers. CONCLUSION: There are hardly any important unknown drug effects that mimic acid related dyspepsia. Drug-induced dyspepsia contributes little to the overall use of ulcer drugs.

Aged↗
PubMed1998

Polypharmacy and the risk of drug-drug interactions among Danish elderly. A prescription database study.

OBJECTIVE: To analyze the use of all subsidized prescription drugs with special attention to the elderly (> or = 70 years of age), including their use of drug combination generally accepted as carrying a risk of severe interactions. DESIGN: Descriptive prevalence study. SETTING: Odense Pharmacoepidemiological Database, Denmark. The fourth quarter of 1994. SUBJECTS: All inhabitants in the county of Funen, Denmark. MAIN OUTCOME MEASURES: Prevalence of drug use for persons < 70 and > or = 70 years of age including number of drugs used and of drug combinations. Occurrence of 45 drug combinations generally accepted as carrying a risk of severe interactions. RESULTS: Among persons less than 70 years, 67.9% used none, 16.5% used one drug and 15.6% used two or more prescription drugs. The corresponding prevalences for the elderly were 35.7%, 15.9% and 48.4%. The 26,337 elderly patients with at least two drugs used 21,293 different combinations. Of the elderly patients who had purchased > or = two drugs, 4.4% had combinations of drugs carrying a risk of severe interactions. CONCLUSIONS: Most elderly use drugs and usually several drugs concomitantly. The elderly form a heterogeneous group of drug users. Drug combinations carrying a risk of severe interactions are relatively frequent.

Aged↗
PubMed1997

[NSAID and ulcer complications. An analysis of risk factors].

Use of NSAIDs is recognized as an important cause of peptic ulcer complications. The aim of this nested case-control study was to identify risk factors for NSAID-related ulcer complications. Cases were consecutive NSAID users admitted with an ulcer complication (n = 94), and controls were a random sample of all NSAID users without ulcer complication identified by a pharmaco-epidemiological database (n = 324). Risk factors for patients at start of NSAID-therapy were: high age: 60-75 yr; Odds Ratio (OR) 3.5 (95% CI: 1.8-7.0); > 75 yr: OR 8.8 (4.3-18.1); male sex: OR 1.7 (1.0-3.0); ulcer history: OR 2.5 (1.2-5.1); steroid treatment: OR 2.0 (0.8-4.6); smoking: OR 1.6 (0.9-2.7); alcohol use: OR 1.8 (0.9-3.6). Risk factors for patients on NSAID-therapy were: high age, male sex, ulcer history, and smoking, and furthermore dyspepsia: OR 2.1 (1.0-4.2), especially NSAID-related dyspepsia: OR 8.9 (4.1-19.2). Risk was lower for patients treated more than three months. In conclusion, risk measured from this design can be shown to correlate strongly with the rate difference, a measure that is more clinically relevant than conventional relative risk estimates. Strong risk factors for NSAID-related ulcer complication are high age, male sex, ulcer history, and dyspepsia related to the NSAID therapy.

Adult↗
PubMed1997

[Antidepressive treatment in general practice--an interview study].

In order to elucidate potential problems concerning the use of antidepressants in general practice, 98 randomly selected antidepressant users from 12 general practices were interviewed. The primary indication for antidepressant treatment was depression (72 patients), partly regular depression (therapeutic/prophylactic treatment) (n = 39), partly depressive tendencies (n = 32) (one patient no information). Median treatment duration was three years; 25% had been in treatment for more than 10 years. The general practitioners judged the treatment problematic/unacceptable in 23 cases, largely because of uncertain indication or because other or no treatment was considered better for the patient. Side effects were modest. The patients often had a relatively high depression score and poor status according to the WONCA-scale. The use of low doses, long duration of treatment, and uncertainty about the relevance of the treatment are important features in the use of antidepressants by general practitioners. The use of antidepressants in general practice differs from the scientifically-based recommendations.

Adult↗
PubMed1997

Changes in the pattern of antidepressant use upon the introduction of the new antidepressants: a prescription database study.

OBJECTIVE: To study whether the newer antidepressants have changed the patterns of antidepressant use, and whether the claimed better adverse effect profile of the lower antidepressants is reflected in their use as monitored by a prescription database. METHOD: By means of a prescription database (OPED), the use of antidepressants from 1991 to 1993 in Odense, Denmark, was analysed. RESULTS: The 1-year prevalence of antidepressant use increased significantly from 1.60% to 2.00%, which still is below the claimed 1-year prevalence of depression of at least 5%. The increase was mainly due to a rapidly increasing use of the newer antidepressants, accompanied by a moderate decline in the use of older antidepressants (mainly tricyclic antidepressants). The patterns of antidepressant use were very polymorphic, with about 5% being on continuous use for all 3 years and groups of each 20-30% being treated with: (1) several series or (2) one series or (3) only by one prescription. The share of patients presenting only one prescription (20%) was the same for older and newer antidepressants. Likewise, the rate of shifts from older to newer antidepressants or vice versa was the same (7% vs 6%). The duration of treatment did not differ much between older and newer antidepressants. Relative to the defined daily dose (DDD), the older antidepressants were given in much lower doses (median 0.63 DDD) than the newer antidepressants (median 1.05 DDD). CONCLUSION: It is concluded that many depressed patients are still not receiving antidepressant treatment and that the claimed better adverse effect profile of the newer antidepressants was not clearly reflected in their use.

Adult↗
PubMed1997

Methods for estimating the occurrence of polypharmacy by means of a prescription database.

OBJECTIVE: Concurrent use of multiple drugs (polypharmacy, PP) may cause health risks such as adverse drug reactions, medication errors and poor compliance. The objective of this study, based on data from a prescription database, was to evaluate estimators of PP in the general population. METHODS: Data were retrieved from Odense Pharmaco-epidemiological Database (OPED) and consisted of all prescriptions in 1994 from a 10% random sample of drug users (n = 26,977) in the county of Funen, Denmark. For each prescription, the period of consumption was calculated by setting the duration of treatment to equal the amount of drug purchased, as measured in defined daily doses (DDD), thereby assuming a daily intake of one DDD. PP was defined as overlapping periods of consumption for different drugs. A Venn diagram was used to illustrate and compare this estimator of PP with two other indicators of multiple-drug use: the number of drugs purchased in 3 months and the mean number of drugs used in 1 year. A receiver operating curve (ROC) was used to evaluate the possibility of predicting episodes of PP from the number of drugs purchased in 3 months. RESULTS: The proposed estimator of PP was robust towards changes in DDD. On an average day in 1994, the prevalence of PP was 9.9% and the standard deviation (SD) between days was 0.3%. Two to four drugs (minor PP) were used by 8.7% of the population (SD, 0.2%) and five or more drugs (major PP) by 1.2% (SD, 0.1%). The number of individuals displaying PP for the first time in 1994 stabilised after approximately 6 months, resulting in an incidence of major PP of 0.2% and of minor PP of 1.2% per month. For individuals exposed to PP, the median number of days of exposure was 61 and 10.5% were exposed for more than 350 days of the year. Purchase of five or more drugs in the first 3 months of 1994 predicted episodes of major PP in the same year with a positive predictive value of 80%. CONCLUSION: Epidemiological measures of multiple drug use can be estimated from data in a prescription database. From a conceptual point of view, an estimator based on the number of simultaneously used drugs (calculated from the date of purchase and the number of DDD) is preferable, but the number of drugs purchased in a 3-month period may also be a useful estimator.

Databases, Factual↗
PubMed1997

Use of sumatriptan in Denmark in 1994-5: an epidemiological analysis of nationwide prescription data.

AIMS: We describe the use of medication with symptomatic relief of migraine as specific indication by analysing prescription data from the entire Danish population in 1994 and 1995. METHODS: The data for sumatriptan were analysed at the level of the individual user. We used aggregated data for ergotamine drugs. RESULTS: Sumatriptan constituted 46% of the total amount of defined daily doses (DDD) sold and 94% of the total pharmacy retail price expenses in the drug-group studied. In total, 43389 users of sumatriptan were identified who presented 340148 prescriptions, corresponding to 2.2 million DDD of sumatriptan. The quarterly consumption increased by 50% during the study period. Tablets accounted for 92% of consumption. The 1 year period prevalence of use of sumatriptan among persons 16 years and older was 7.8 per 1000 in 1995 with a female to male prevalence ratio of 3.8:1. Use was most common in the age interval 35-54 years. Regional differences in use, which were not large, were positively correlated to the degree of urbanization. The incidence of use of sumatriptan was estimated at 3.6 per 1000 person-years. The intensity of use of sumatriptan varied greatly with 1.1% of patients (n = 507) using 60 DDD or more within 30 days at some time during the observation period. Long-term high use of tablets was common in this group. CONCLUSIONS: We conclude that sumatriptan had a considerable impact on the treatment of migraine with prescription drugs in Denmark. The underlying reasons for high use of the drug in a smaller fraction of the patients deserve further study.

Adolescent↗