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H G Leufkens

Publications and source records attributed to H G Leufkens.

At least 19 recordsLinked to original sources
PubMed2005

Dyspepsia in chronic psychiatric patients.

INTRODUCTION: We report on dyspeptic complaints among patients hospitalized in the long-stay ward of a general psychiatric hospital. METHODS: A representative sample of the patients was interviewed using a structured questionnaire. RESULTS: Eighty percent of the patients reported one or more symptoms of dyspepsia, and 68 % reported symptoms of reflux-like dyspepsia. CONCLUSION: Significant positive associations were found for dyspepsia complaints and clozapine (OR = 3.4), laxatives (OR = 4.4), and heavy smoking (OR = 2.3).

Adult↗
PubMed2004

Reduction in the therapeutic intensity of abortive migraine drug use during ACE inhibition therapy--a pilot study.

INTRODUCTION: Since a few case reports have demonstrated some beneficial effects of angiotensin converting enzyme (ACE) inhibitors in migraine prevention, we were interested in studying the impact of ACE inhibitors and angiotensin II receptor antagonists (Ang II) on the consumption of specific abortive migraine drugs and, therefore, indirectly on the frequency of migraine attacks. METHODS: Data from a large prescription database involving 95 patients initiating a specific abortive migraine drug (ergotamine or a triptan) and subsequently treated with either an ACE inhibitor or angiotensin receptor antagonist (index group: ACE/Ang II) or diuretic (reference group) were analysed. The effects of ACE/Ang II inhibition as well as diuretic therapy on reducing the frequency of migraine attacks were assessed by measuring the mean consumption of abortive migraine drug use, in DDDs per month ('therapeutic intensity'), before, during and after ACE/Ang II or diuretic therapy. A 'therapeutic fluctuation intensity estimate' of abortive migraine drug use for all patients was likewise calculated. RESULTS: On an individual level, the therapeutic intensity (TI) fluctuation estimate, 'during' relative to 'before' ACE diuretic therapy, was significantly larger for the ACE/Ang II group (62% reduction) than for the diuretic group (24% reduction) (p = 0.02). For patients who continued abortive migraine drug use during and after ACE/Ang II or diuretic therapy, a significantly larger reduction in this estimate was observed during ACE/Ang II inhibition (68.9%) compared to during diuretic therapy (10.5% increase) (p = 0.004). The TI fluctuation estimate, after relative to 'during', had increased by 50.3% after ACE/Ang II inhibition and had reduced by 22.2% after diuretic treatment (p = 0.1). CONCLUSIONS: A clear reduction in the TI of abortive migraine drug use during the use of ACE inhibitors as compared to diuretic treatment was observed. Our findings may indirectly support a positive effect of ACE/Ang II inhibition on the frequency and severity of migraine attacks, as observed in other studies and reports.

Adolescent↗
PubMed2003

Migraine prophylactic medication usage patterns in The Netherlands.

This study aims to investigate usage patterns of specific migraine prophylactic medications in ergotamine and triptan patients commencing this treatment for the first time during 1 January 1992 until 31 December 1998. Usage patterns of specific migraine prophylactic drugs were evaluated for each patient by accessing data from a large prescription database and were characterized as continued, switch or stop use during the patient observation period. Several patient and medication-related factors were explored in order to identify a possible relationship with the specific usage pattern defined. Approximately 75% of the study population (n = 729) had terminated (stop or switch) prophylactic treatment after 1 year. Age < 40 years (relative risk (RR) 1.9; 95% confidence interval (CI) 1.2-3.2) and the concomitant use of non-steroidal anti-inflammatory drugs (RR 3.2; 95% CI 1.2-5.5) or specific abortive migraine drugs resulted in a faster onset of treatment modification (switch). Overall, migraine prophylactic treatment is used for a relatively short period, probably attributable to the common limitations associated with migraine prophylaxis, such as poor compliance and/or limited therapeutic efficacy. Patterns of use can be influenced by a variety of factors, including age, type of prescriber and certain co-medication. Patient interview studies are required to clarify these issues further.

Adrenergic beta-Antagonists↗
PubMed2003

Single use of sumatriptan: a patient interview study.

OBJECTIVE: To investigate the possible reasons associated with the use of a single prescription of sumatriptan. BACKGROUND: A few population-based studies concerning the usage patterns of sumatriptan have revealed a relatively high incidence (approximately 40%) of sumatriptan users who utilize only a single prescription of the drug. DESIGN AND METHODS: Using automated prescription data from 11 community pharmacies, we identified single and multiple sumatriptan prescription recipients. The data were collected from May 1, 1998, to April 30, 2000. Several patient- and medication-related variables possibly associated with single recipiency of sumatriptan were analyzed. In addition, single recipients of sumatriptan were invited for an interview and asked a number of questions related to their clinical status and their experience with the medication. RESULTS: Four hundred ninety-five, first-time users of sumatriptan were identified during the patient selection period, of whom 38% were single recipients of sumatriptan. Of the latter, 102 patients were considered eligible for interview. Reasons for terminating treatment after only 1 prescription included: inefficacy and/or occurrence of side effects, 78% (n=79); uncertain diagnosis of migraine, 39.2% (n=40); and reduction in headache frequency, 33.3% (n=34). Almost half of the population had terminated treatment without having consulted their physician. More than half relied upon the use of over-the-counter (OTC) analgesics after having tried sumatriptan. Compared to multiple users of sumatriptan, single recipients were far less likely to have used another form of migraine treatment prior to (odds ratio, 0.35; [95% confidence interval, 019 to 0.67]) and after (odds ratio, 0.34 [95% confidence interval, 0.19 to 0.63]) initiating sumatriptan. Furthermore, single recipients had demonstrated an increased tendency towards benzodiazepine use prior to receiving sumatriptan (odds ratio, 1.80 [95% confidence interval, 1.00 to 3.28]). CONCLUSIONS: Single use of a sumatriptan prescription reveals some issues that may impact negatively the provision of effective migraine management. These include: rapidly developing dissatisfaction with the treatment provided and a lower tendency to seek out medical care. Our results also suggest that the drug may be used (inappropriately) as a diagnostic tool.

Adult↗
PubMed2003

Incidence and determinants of antidepressant drug use in migraine patients.

The purpose of this retrospective, follow-up study was to characterise the use of antidepressant medication in a defined migraine population and evaluate the determinants thereof. Data was obtained from the PHARMO-RLS prescription database. Our migraine population (2,517 people) included patients having commenced specific migraine drugs, ergotamine or sumatriptan, for the first time from January 1 1992 to December 31 1998. The corresponding date was termed the 'index date'. Non-migraine patients, those not having used any medication specific for migraine, were selected and equally matched (n=2,517). The cumulative incidence of initiating antidepressant treatment was estimated during two-year observation periods prior to and after the index date. Several demographic and comedication characteristics were assessed as potential determinants of antidepressant drug use within the migraine population. Other determinants included usage patterns ("therapeutic intensity") of ergotamine and sumatriptan, defined as the absolute number of Defined Daily Doses (DDDs) dispensed per patient during one year prior to initiation of antidepressant therapy. A total of 300 migraine patients (11.9%) and 213 non-migraine patients (8.5%) had initiated antidepressant treatment in the two-year period prior to or in the two-year period after the index date (RR adj 1.4; 95% CI 1.2-1.7). The cumulative incidence of initiation of antidepressant treatment for the migraine population was 3.0% per year prior to and 3.2% per year after the initiation of specific migraine analgesia. The concomitant use of benzodiazepines (RR adj 4.7; 95% CI 3.5-6.3), migraine prophylactic medication (RR adj 2.1; 95% CI 1.6-2.8) and heavy therapeutic intensity use of specific migraine analgesia, defined as >/=150 DDDs per year were highly predictive of antidepressant drug use within the migraine population. In conclusion, compared to the non-migraine population, the initiation of antidepressant treatment was only slightly higher in the migraine population. A number of determinants within the latter were found to be strongly associated with antidepressant drug use, the nature of which most likely reflects an increased severity of migraine whereby therapeutic needs are higher.

Adult↗
PubMed2002

Incidence and determinants of migraine prophylactic medication in the Netherlands.

OBJECTIVE: To estimate and examine the incidence and determinants of initiation of migraine-prophylactic therapy as well as the corresponding drug of choice over a period of 5 years following the use of specific abortive migraine drugs. METHODS: By accessing data from a large prescription database, an identification of patients treated with ergotamine or a triptan from 1 January 1994 to 31 December 1998 was made. The cumulative incidence of initiation of migraine-prophylactic drugs (beta-blockers, serotonin antagonists, specific calcium antagonists, amitriptyline, clonidine and valproic acid) was estimated in patients following the use of ergotamine or a triptan. An assessment of the migraine-prophylactic drug of first choice was also performed. A few baseline determinants were analysed to highlight a possible association with the initiation of prophylactic therapy: age, gender, type of abortive migraine drug use and year of prophylaxis. Additional determinants included the analysis of drug-utilisation patterns, such as the consumption and switch patterns of abortive migraine drug use as well as co-medication use prior to prophylaxis. For this particular analysis a reference group (patients not having commenced prophylaxis) was selected from the initial study population. RESULTS: After having satisfied eligibility criteria, a total of 3999 first-time users of ergotamine and triptans were included of whom 479 (12%) had initiated migraine-prophylactic therapy. This corresponded to an incidence density of 6.0 per 100 person-years and was highest for patients younger than 45 years and for multiple abortive migraine drug users. The incidence fell considerably from 12.0 person-years in 1994 to 5.1 person-years in 1998. More than half of the patients had been prescribed a beta-blocker as the migraine-prophylactic drug of first choice by both general practitioners and neurologists. The use of antidepressants and/or benzodiazepines and oral contraceptives was significantly higher in patients starting prophylaxis compared with those who did not. The consumption of abortive migraine drug use (4.0 defined daily doses per month vs 3.7 defined daily doses per month), and switch patterns (27.1% vs 30.9%) were similar for patients starting and not starting prophylaxis. CONCLUSION: The overall incidence of initiation of migraine-prophylactic therapy following the use of abortive migraine analgesics was 6.0% per year and fell considerably during 5 years of the study. Beta-blockers were the migraine-prophylactic drugs of first choice for general practitioners and neurologists. In our study we could not determine any factors clearly associated with the initiation of migraine prophylaxis besides prior use of antidepressants and benzodiazepines. A future assessment of the usage patterns of migraine-prophylactic drugs may provide detailed information concerning the effectiveness and tolerability.

Adrenergic beta-Antagonists↗
PubMed2002

Psychotropic drug use in intellectually disabled group-home residents with behavioural problems.

Little is known about psychiatric and behavioural factors associated with psychotropic drug use and how appropriately these drugs are prescribed in settings for people with intellectual disabilities. The aim of this study was to measure the point prevalence of psychotropic drug use in a problem-behaviour group (PBG) consisting of intellectually disabled residents of group homes compared to a random group (RG), and to gain insight in possible factors that are associated with group membership. From all group homes in the Netherlands, 573 problematic residents were selected by the staff (one resident from each home) and 1479 residents were randomly sampled from all of the homes. Mental health problems were measured using the Reiss Screen for Maladaptive Behaviour and the Psychopathology Instrument for Mentally Retarded Adults. The response rate in the PBG was 68.9 % and in the RG 71.7 %. Psychotropics (excluding anticonvulsants) were used by 52.6 % of the PBG and by 22.8 % of the RG. Young age, psychotic, anxiety, and aggression symptoms were significantly associated with the PBG, as was the use of antipsychotics and antidepressants. The PBG more often used multiple (three or more) drugs (17.3 %) than the RG (7.3 %). A low prevalence of antidepressants or mood stabilisers, antipsychotics, and anxiolytics was found in residents with affective, psychotic, or anxiety symptoms. We conclude that psychotropic drug use in the PBG compared to the RG was high. It is likely that the group-home staff finds it difficult to deal with young people with socially disruptive behaviour, which is underlined by our finding of high prevalence of antipsychotics and multiple-drug therapy in the PBG. Finally, our findings suggest that a considerable number of residents with psychiatric or behavioural symptoms are undertreated.

Adolescent↗
PubMed2001

Antihypertensive drug therapies and the risk of ischemic stroke.

BACKGROUND: The relative effectiveness of various antihypertensive drugs with regard to the reduction of stroke incidence remains uncertain. OBJECTIVE: To assess the association between first ischemic stroke and use of antihypertensive drugs. METHODS: A population-based case-control study was performed among enrollees of the Group Health Cooperative of Puget Sound. Case patients included pharmacologically treated hypertensive patients who sustained a first ischemic stroke (fatal or nonfatal; n = 380) between July 1, 1989, and December 31, 1996. Control subjects were a random sample of treated hypertensive enrollees without a history of a stroke (n = 2790). Medical record review and a telephone interview of consenting survivors were used to collect information on risk factors for stroke. Computerized pharmacy records were used to assess antihypertensive drug use. RESULTS: Among 1237 single-drug users with no history of cardiovascular disease, the adjusted risk of ischemic stroke was higher among users of a beta-blocker (risk ratio [RR], 2.03; 95% confidence interval [CI], 1.05-3.94), calcium channel blocker (RR, 2.30; 95% CI, 1.16-4.56), or angiotensin-converting enzyme inhibitor (RR, 2.79; 95% CI, 1.47-5. 27) than among users of a thiazide diuretic alone. Among 673 single-drug users with a history of cardiovascular disease, the RRs were 1.22 (95% CI, 0.63-2.35), 1.18 (95% CI, 0.59-2.33), and 1.45 (95% CI, 0.70-3.02) among users of a beta-blocker, calcium channel blocker, and angiotensin-converting enzyme inhibitor, respectively, compared with users of a thiazide diuretic alone. CONCLUSIONS: In this study of pharmacologically treated hypertensive patients, antihypertensive drug regimens that did not include a thiazide diuretic were associated with an increased risk of ischemic stroke compared with regimens that did include a thiazide. These results support the use of thiazide diuretics as first-line antihypertensive agents.

Adrenergic beta-Antagonists↗
PubMed2001

Tendon disorders attributed to fluoroquinolones: a study on 42 spontaneous reports in the period 1988 to 1998.

OBJECTIVE: Fluoroquinolone antibiotics have been associated with tendinitis and tendon rupture. In this paper we report on the followup of 42 spontaneous reports of fluoroquinolone-associated tendon disorders. METHODS: This study is based on cases of fluoroquinolone-associated tendon disorders reported to the Netherlands Pharmacovigilance Foundation Lareb and the Drug Safety Unit of the Inspectorate for Health Care between January 1, 1988, and January 1, 1998. By means of a mailed questionnaire, we collected information on the site of injury, onset of symptoms, treatment, and course of the tendon disorder as well as information on possible risk factors and concomitant medication. RESULTS: Of 50 mailed questionnaires, 42 (84%) were returned. The data concerned 32 patients (76%) with tendinitis and 10 patients (24%) with a tendon rupture. Sixteen cases (38%) were attributed to ofloxacin, 13 (31%) to ciprofloxacin, 8 (19%) to norfloxacin, and 5 (12%) to pefloxacin. There was a male predominance, and the median age of the patients was 68 years. Most of the reports concerned the Achilles tendon, and 24 patients (57%) had bilateral tendinitis. The latency period between the start of treatment and the appearance of the first symptoms ranged from 1 to 510 days with a median of 6 days. Most patients recovered within 2 months after cessation of therapy, but 26% had not yet recovered at followup. CONCLUSION: These reports suggest that fluoroquinolone-associated tendon disorders are more common in patients over 60 years of age. Ofloxacin was implicated most frequently relative to the number of filled prescriptions in the Netherlands.

Adult↗
PubMed2001

Antipsychotic-induced extrapyramidal syndromes. Risperidone compared with low- and high-potency conventional antipsychotic drugs.

AIM: To compare the risk of extrapyramidal syndromes (EPS) between patients using risperidone and those using low-potency conventional antipsychotic drugs (APDs) in outpatient clinical practice, as measured by the use of anticholinergic medication. We tried to replicate results from previous clinical trials that compared risperidone with high-potency APDs. METHOD: Data was obtained from the PHARMO database containing filled prescriptions of 450,000 community-dwelling people in The Netherlands from 1986 to 1998. From the patients aged 15-54 years who had been newly treated with APDs, we defined mutually exclusive cohorts according to the APD first prescribed to a patient. APD exposure was followed until the first prescription of anticholinergic medication and was censored when APD prescribing was interrupted or switched. We estimated relative risks between risperidone and commonly used low-potency and high-potency APDs using Cox proportional hazards models, adjusting for age, gender, dose and other potential confounders. RESULTS: In 4094 patients who had been newly prescribed antipsychotic drugs, the overall incidence rate of anticholinergic drug therapy was 556 per 1000 person-years, which was dose dependent. Prescribed doses of all antipsychotics were low. While, in accordance with previous trials, risperidone showed a lower risk of EPS than the high potency APDs such as haloperidol (RR 0.26; 95% CI 0.10-0.64), we did not observe a lower EPS rate than low-potency APDs (risperidone vs thioridazine RR 1.73, 95% CI 0.49-6.13; risperidone vs pipamperone RR 2.50, 95% CI 0.78-8.04). CONCLUSION: The reduced EPS rates observed when comparing risperidone with high-potency antipsychotics such as haloperidol may not apply to comparisons with low-potency drugs.

Adolescent↗
PubMed2001

Costs and effects of combining stenting and abciximab (ReoPro) in daily practice.

AIM: The combined use of stents and abciximab in percutaneous coronary intervention has been evaluated in the EPISTENT trial. However, the clinical and economic findings in trials are not necessarily generalisable to a general population setting. We conducted a study in daily clinical practice comparing stented and non-stented patients undergoing coronary angioplasty with abciximab administration. Furthermore, we compare our results with the findings of the EPISTENT trial. METHODS: From 1995 to 1999, refractory unstable patients scheduled for angioplasty and receiving abciximab in a Dutch regional hospital were followed prospectively for 6 months. Total costs were considered in addition to 2 composite clinical endpoints: (1) death or myocardial infarction (MI); and (2) death, MI, or any revascularisation procedure (major adverse cardiac events, MACE). RESULTS: Stented patients (N=101) experienced less MACE than non-stented patients (N=83) (6.9% vs. 16.9%, OR=0.37, P=0.04). The total costs were similar for stented and non-stented patients (EUR 7 844 vs. EUR 7 904, P=0.93). Adjustment for baseline characteristics yielded similar results, although significance subsided. The relative risk reduction of 44% that we found, closely resembles the 42% that was found in the EPISTENT trial. CONCLUSIONS: In everyday practice, as in the EPISTENT trial, the addition of a stent to abciximab treatment does seem to reduce the risk of MACE by about 40% at no additional costs.

Abciximab↗
PubMed2001

Evaluating adverse cardiovascular effects of drug treatment for benign prostatic hyperplasia (BPH): methodological considerations.

When studying the effects of drug exposure in diseases with a long asymptomatic clinical course, exposure classification may be biased by the gradually developing "visibility" of the disease. Benign prostatic hyperplasia (BPH) is such a disease. We found that cardiovascular morbidity is two times more prevalent in patients starting drug treatment for BPH when compared to age-matched population controls. This resulted in a difference of cardiovascular prognostic factors between the exposed and non-exposed. This feature can jeopardize the validity of non-randomized comparisons of drug effects. Moreover, the existence of non-treatment strategies, disease under-reporting, and an elderly population with a high baseline risk of experiencing (cardiovascular) outcome events were encountered as methodological problems. When studying adverse cardiovascular effects in patients using BPH products in a non-randomized fashion, an important question is whether we can measure in the database all relevant prognostic factors and use the information for statistical adjustment. This question is an important challenge to observational research and once again stresses the need for control of possible biases in choosing an appropriate study design.

5-alpha Reductase Inhibitors↗
PubMed2001

Epidemiology of fractures in England and Wales.

Records from the General Practice Research Database were used to derive age- and gender-specific fracture incidence rates for England and Wales during the period 1988-1998. In total, 103,052 men and 119,317 women in the sample of 5 million adults sustained a fracture over 10.4 million and 11.2 million person-years (py) of follow-up. Among women, the most frequent fracture sites were the radius/ulna (30.2 cases per 10,000 py) and femur/hip (17.0 per 10,000 py). In men, the most common fracture was that of the carpal bones (26.2 per 10,000 py); the incidence of femur/hip fracture was 5.3 per 10,000 py. Varying patterns of fracture incidence were observed with increasing age; whereas some fractures became more common in later life (vertebral, distal forearm, hip, proximal humerus, rib, clavicle, pelvis), others were more frequent in childhood and young adulthood (tibia, fibula, carpus, foot, ankle). The lifetime risk of any fracture was 53.2% at age 50 years among women, and 20.7% at the same age among men. Whereas fractures of the proximal femur and vertebral body were associated with excess mortality over a 5 year period following fracture diagnosis among both men and women, fractures of the distal forearm were associated with only slight excess mortality in men. This study provides robust estimates of fracture incidence that will assist health-care planning and delivery.

Adult↗
PubMed2001

Determinants of change in the intention to use benzodiazepines.

OBJECTIVE: To examine attitudes and beliefs associated with changes in the intention to use benzodiazepines during the six-month period after first benzodiazepine use. DESIGN: Population-based 6-month follow-up with 3 measurement points (baseline, 2 weeks after inclusion, 6 months after inclusion). SETTING: Starting or initial benzodiazepine users were included during a period of 4 months from November 1994 in the only pharmacy of a Dutch community of 13,500 people. MEASURES: Variables proposed by the Model of Planned Behaviour and the Health Belief Model. Drug exposure data from automated pharmacy records. RESULTS: At baseline, the intention to use benzodiazepines was primarily predicted by the perceived norm of the general practitioner regarding benzodiazepine use, and by the participants' own attitudes. After fourteen days, the determinants of change in the intention to use benzodiazepines were the initially perceived norm of the general practitioner and the change in the severity of participants' illnesses. After six months, the change in the severity of the illness and the perceived health benefits of benzodiazepines at the time of inclusion were the main determinants of the change in the intention to use benzodiazepines between the second and third measurement point. The intention to use benzodiazepines showed a decrease during follow-up. The three intention measures were significant predictors of actual benzodiazepine use during the year following baseline assessment. CONCLUSION: The study sheds light on interesting determinants of decrease or increase in the intention to use during the six-month period after first benzodiazepine use.

Adult↗
PubMed2001

Fluoroquinolone use and the change in incidence of tendon ruptures in the Netherlands.

INTRODUCTION: Shortly after their introduction, fluoroquinolones were associated with reports of tendinitis and tendon rupture. During the past years, the number of reports has risen, possibly because of an increased use of fluoroquinolones. In this study, we describe the use of fluoroquinolones in the Dutch community and the possible public health effects of an association between fluoroquinolone use and tendon ruptures. METHODS: In the PHARMO drug database we identified all prescriptions for fluoroquinolones in the period 1991-1996. The incidence of fluoroquinolone use was expressed as the number of fluoroquinolone episodes per 1000 inhabitants in one year, and extrapolated to the Dutch population after standardisation on age and gender. The annual incidence of non-traumatic tendon ruptures in the period 1991-1996 was calculated with data from the nation-wide hospital registry. The expected number of fluoroquinolone attributable tendon ruptures was calculated on the basis of the use of fluoroquinolones, the number of non-traumatic tendon ruptures and an assumed relative risk of 1.5-10. RESULTS: In 1996, approximately 251,000 patients experienced 318,000 episodes of fluoroquinolone use in the Netherlands. Females used more often fluoroquinolones than males, and the number of episodes increased exponentially with age. In the period 1991 through 1996, the absolute number of fluoroquinolone episodes increased by 160%, from 122,000 to 318,000. The absolute number of hospitalised tendon ruptures increased with 28%, from 768 in 1991 to 984 in 1996. Assuming a relative risk of 1.5 to 10.0, 1 to 15 tendon ruptures could be attributed to fluoroquinolone use in 1996. Only 7% of the observed increase could be attributed to the increased use of fluoroquinolones. If the total increase of hospitalised non-traumatic tendon ruptures would be attributable to the increase in fluoroquinolone use, this would mean that the risk of non traumatic tendon ruptures to fluoroquinolones would be more than 250 times the risk during non-use. CONCLUSION: In the Netherlands, a large simultaneous increase in non-traumatic tendon ruptures and fluoroquinolone use was observed in the period between 1991 to 1996. Assuming a relative risk of 1.5 to 10.0 for tendon ruptures during fluoroquinolone use, only 0.5 to 7% of the increase in non-traumatic tendon ruptures could be attributed to the increased fluoroquinolone use. The increase in the incidence of non-traumatic hospitalised tendon ruptures in the Netherlands is not likely to be explained solely by the increased use of fluoroquinolones.

Adult↗
PubMed2001

Determinants of pharmacists' interventions linked to prescription processing.

AIM OF STUDY: The role of pharmacists in today's healthcare is changing rapidly. As they are close to the prescribing process, pharmacists are in the position to identify and adjust prescribing errors before dispensing. The objective of this study was to identify relevant determinants of interventions directly linked to prescription processing in community pharmacy. METHODS: As part of a yearly continuing education programme, all community pharmacies in the region of 'Zealand' (N = 23) in the south-west of The Netherlands kept detailed records of all interventions directly linked to prescription processing during one week in May 1998. For every patient involved in an intervention, a control-patient was matched on pharmacy practice, date, gender and age. RESULTS: A total of 39,357 prescriptions were evaluated by the 23 pharmacies during the one-week intervention programme. Out of these, one out of 10 resulted into an intervention. Being a first prescription in a new treatment episode was found to be a significant determinant (OR 1.75, 95 CI% 1.18-2.33). Variables reflecting drug therapy complexity (> 3 prescribers, > 15 prescriptions in 3 months before, > 3 different medications) showed all ORs higher than 1.00, but not significant. When looking at the individual drug categories, anti-infectives, respiratory drugs and cardiovascular medicines came out as important drug classes for intervention risk. We could not find any association between the number of signals per pharmacy and the number of interventions. CONCLUSION: The 'whistle-blower' model of pharmacy based interventions is a valid one but needs a targeted and integral way of implemented thinking and use of information technology. In such an environment, interventions are a logical step of in-process quality control in the drug usage system.

Aged↗