Inappropriate use of sumatriptan: population based register and interview study.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to D Gaist.
Explore the source record for details and available documents.
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.
The emergence of large, computerized pharmacoepidemiologic databases has enabled us to study drug utilization with the individual user as the statistical unit. A recurrent problem in such analyses, however, is the overwhelming volume and complexity of data. We here describe a graphical approach that effectively conveys some essential utilization parameters for a drug. The waiting time distribution for a group of drug users is a charting of their first prescription presentations within a specified time window. For a drug used for chronic treatment, most current users will be captured at the beginning of the window. After a few months, the graph will be dominated by new, incident users. As examples, we present waiting time distributions for insulin, ulcer drugs, systemic corticosteroids, antidepressants, and disulfiram. Appropriately analyzed and interpreted, the waiting time distributions can provide information about the period prevalence, point prevalence, incidence, duration of use, seasonality, and rate of prescription renewal or relapse for specific drugs. Each of these parameters has a visual correlate. The waiting time distributions may be an informative supplement to conventional drug utilization statistics, and possibly also a useful screening tool for unusual prescribing patterns.
Theophylline is predominantly metabolized by cytochrome P4501A2 (CYP1A2). A possible interaction between griseofulvin and theophylline was reported to our laboratory, which led us to form the hypothesis that griseofulvin induces the metabolism of theophylline. One purpose of this study was to investigate this hypothesis. The study was carried out as a randomized crossover study of 12 healthy volunteers. In period A of the study, each volunteer received a single dose of 300 mg theophylline ethylenediamine orally. In period B, the subjects took fluvoxamine, 50 mg for 1 day and 100 mg for 6 days, and on day 4, the subjects ingested 300 mg theophylline ethylenediamine. Fluvoxamine is a potent inhibitor of CYP1A2, and period B was included as a positive control. In period C, the subjects took 500 mg griseofulvin for 9 days; on day 8 the subjects again ingested 300 mg theophylline ethylenediamine. Theophylline and its metabolites (1-methyluric acid [IMU], 3-methylxanthine [3MX], and 1,3-dimethyluric acid [13DMU]) in plasma and urine were assayed by high-performance liquid chromatography. During fluvoxamine intake, the median of the total clearance of theophylline decreased from 80 ml/min to 24 ml/min, and the half-life increased from 6.6 to 22 h. The partial formation clearances of the metabolites decreased from 17 to 1.7 ml/min, from 8.9 to 0.9 ml/min, and from 21 to 6.8 ml/min for 1MU, 3MX, and 13DMU, respectively. The results confirm that assessment of theophylline metabolism indeed serves as a biomarker for CYP1A2. During griseofulvin ingestion, the median of the total and partial clearances of theophylline were 84 ml/min, 22 ml/min (1MU), 9.4 ml/min (3MX), and 25 ml/min (13DMU). The half-life decreased significantly from 6.6 to 5.7 h. The increase in partial formation clearances of 1MU and 13DMU, but not of 3MX, were statistically significant. The increase in the total clearance reached only borderline significance. In four subjects a marked induction was seen for all pharmacokinetic parameters, suggesting that the susceptibility to induction is more pronounced in some subjects. This susceptibility could theoretically be explained by a polymorphism in the inducibility of the gene coding for the CYP1A2 enzyme.
The extensive computerisation of Danish pharmacies has permitted the establishment of two large prescription registries: The Odense University Pharmacoepidemiological Database (OPED) and the Pharmacoepidemiological Prescription Database of North Jutland (PDNJ). The Danish prescription registries content, coverage, completeness and the quality of the data are discussed in this article. Furthermore, conditions for access to the data are presented. The two prescription registries cover a background population of approximately one million or 18% of the Danish population. The populations covered by the registries are stable and representative of the Danish population in general. The registries cover all reimbursed medicine at the level of the individual user. Registration of a unique and permanent personal identifier enables the compilation of longitudinal drug histories and allows the linking of prescription data to other population-based Danish registries. The degree of completeness of the Danish prescription registries is excellent for reimbursed prescription drugs. A small number of comparison studies also indicate high validity of the register information. The Danish prescription registries represent a useful new data source for pharmacoepidemiological studies.
Spontaneous reporting systems (SRS) have been established to monitor drug safety problems after marketing, especially rare, but serious adverse drug reactions (ADRs). Among these are the skin disorders erythema multiforme (EM), Stevens- Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). The purpose of this study has been to evaluate the data on these serious skin disorders available in a SRS. All reports concerning these diseases submitted to the Danish Committee on ADRs during the period 1968 to 1991 were reviewed according to predefined criteria. Information was often scarce,and the diagnosis of the reporter had to be accepted at face value in 28% of cases. Two hundred cases of EM, 74 of SJS and 29 of TEN were identified. More than 60% of cases were hospitalized. The diseases had fatal outcome in six patients with TEN, three with SJS and a single patient suffering from EM. One hundred and twenty-eight different drugs were reported as causal agents. Major drug groups involved were antibiotics (sulphonamides and penicillins), non-steroidal anti-inflammatory drugs, anti-epileptics and analgesics. Incidence estimates based on spontaneous reports were compared to the incidence according to the literature and data from a nationwide hospital discharge diagnosis register. The reporting fraction for EM and SJS is estimated to 10-30%, and for TEN to 25-50%, but the validity of reports is in some cases difficult to assess owing to lack of detail.
OBJECTIVE: Sumatriptan is highly efficacious in aborting acute attacks of migraine. Owing to recent reports of misuse of sumatriptan, we performed a study of its use in a Danish population. METHODS: Data were retrieved from a prescription database covering a period of 27 months after release of the drug. Consumption was described by the defined daily dose (DDD) unit and total individual consumption during the period was calculated. Those who received more than one prescription for sumatriptan were classified according to peak use of sumatriptan into high (> or = 60 DDD/31 days) (n = 45), intermediate (30-59 DDD/31 days) (n = 127) and low (< 30 DDD/31 days) (n = 1423) consumption groups. Individual usage of other medication was described. RESULTS: We identified 2,878 users of sumatriptan, of whom 1,283 (45%) only redeemed one prescription. The use of sumatriptan was highly skewed. The 1% heaviest users accounted for 20% of the total consumption. The median total individual consumption of sumatriptan was 500 DDD, 192 DDD, and 24 DDD in the three groups of multiple redeemers, respectively. Pronounced differences in the total amounts of opioids and ergot alkaloids used were also found, with the high peak consumption group being the heaviest consumers of all drug categories, although half of them had only received large doses of sumatriptan. Fifty seven % of high peak users redeemed more than 29 DDD of sumatriptan within one month of initiation of treatment. The 45 high peak users had received the bulk of their medication, largely in tablet formulation, from 31 prescribers. The data points to rebound headache as a plausible underlying mechanism, but incorrect use of sumatriptan for migraine prophylaxis is also a possibility. Overuse of sumatriptan has serious economic consequences and its long-term health effects are not known.
1. We conducted a descriptive cross-sectional study of asthma therapy among young adults to assess to what extent the current guidelines for asthma therapy have been implemented. In particular, we examined the use of inhaled corticosteroids in heavy users of inhaled beta-adrenoceptor agonists. 2. Data were retrieved from a population-based prescription database. For each of the years 1991 and 1994, all 20 to 44-year-olds who redeemed anti-asthma medication in the Odense area (210,000 inhabitants) were studied. 3. We identified the number of users and total sales volume for specific anti-asthma medications in defined daily doses (DDD) as well as the number of users and median annual doses of common regimens. Combined use of inhaled corticosteroids and inhaled beta-adrenoceptor agonists was also described. 4. The annual sales volume of anti-asthma drugs increased by 23% to 927,636 DDD from 1991 to 1994. Inhaled corticosteroids were mainly responsible for this with a 52% increase in number of users and an 88% increase in DDD. Inhaled beta-adrenoceptor agonists used in monotherapy remained the most popular regimen in 1994 (1685 users = 39%). Inhaled corticosteroids in combination with inhaled beta-adrenoceptor agonist were the second most popular regimen in 1994 (1308 users = 30%), increasing by 64% as compared with 1991. However, among patients with an annual use of inhaled beta-adrenoceptor agonist of 200 DDD (1600 "puffs') or more the percent of patients not receiving inhaled corticosteroids at all only fell from 37 to 33%. Though the number of patients being treated with inhaled corticosteroids has increased, there is still evidence of a substantial underuse.
Explore the source record for details and available documents.
A case of Whipple's disease (WD) initially presenting with migrating arthralgia and later with weight loss, malaise, fever and abdominal discomfort is reported. On examination the patient showed signs of malnutrition, was anaemic and pyrexial (37.6-38.8) and had mild abdominal distention. Retroperitoneal lymph node enlargement was demonstrated by CT-scanning. Gastroduodenoscopy demonstrated white plaques and erosions in the 2nd and 3rd part of the duodenum. Repeated small bowed biopsies revealed pathological changes typical of WD. The patient was treated with parenteral penicillin 2 MIE t.i.d. for 14 days followed by sulfamethoxazole 800 mg and trimethoprim 160 mg b.i.d for a year. Response to treatment was satisfactory. Serum alkaline phosphatase levels were raised: 324-649 U/l (80-275) on admission and remained so following treatment.
Explore the source record for details and available documents.