Assessment of pediatric asthma drug use in three European countries; a TEDDY study

Asthma drugs are amongst the most frequently used drugs in childhood, but international comparisons on type and indication of use are lacking. The aim of this study was to describe asthma drug use in children with and without asthma in the Netherlands (NL), Italy (IT), and the United Kingdom (UK). We conducted a retrospective analysis of outpatient medical records of children 0-18 years from 1 January 2000 until 31 December 2005. For all children, prescription rates of asthma drugs were studied by country, age, asthma diagnosis, and off-label status. One-year prevalence rates were calculated per 100 children per patient-year (PY). The cohort consisted of 671,831 children of whom 49,442 had been diagnosed with asthma at any time during follow-up. ß2-mimetics and inhaled steroids were the most frequently prescribed asthma drug classes in NL (4.9 and 4.1/100 PY), the UK (8.7 and 5.3/100 PY) and IT (7.2 and 16.2/100 PY), respectively. Xanthines, anticholinergics, leukotriene receptor antagonists, and anti-allergics were prescribed in less than one child per 100 per year. In patients without asthma, ß2-mimetics were used most frequently. Country differences were highest for steroids, (Italy highest), and for ß2-mimetics (the UK highest). Off-label use was low, and most pronounced for ß2-mimetics in children <18 months (IT) and combined ß2-mimetics + anticholinergics in children <6 years (NL).

CONCLUSION

This study shows that among all asthma drugs, ß2-mimetics and inhaled steroids are most often used, also in children without asthma, and with large variability between countries. Linking multi-country databases allows us to study country specific pediatric drug use in a systematic manner without being hampered by methodological differences. This study underlines the potency of healthcare databases in rapidly providing data on pediatric drug use and possibly safety.

Risk of recurrent myocardial infarction with the concomitant use of clopidogrel and proton pump inhibitors

BACKGROUND

The association between myocardial infarction (MI) and co-administration of proton pump inhibitors (PPIs) and clopidogrel remains controversial.

AIM

To quantify the association between concomitant use of PPIs and clopidogrel and occurrence of recurrent MI.

METHODS

We conducted a case-control study within a cohort of acute MI patients in PHARMO Record Linkage System (1999-2008). The cases were patients readmitted for MI. PPI exposure was categorized as current (3-1 days before MI), past (30-3 days before MI), or no use (>30 days before MI). We used conditional logistic regression analyses.

RESULTS

Among 23 655 patients hospitalized following MI, we identified 1247 patients readmitted for MI. Among clopidogrel users, current PPI use was associated with an increased risk of recurrent MI (OR: 1.62, 95% CI: 1.15-2.27) when compared with no PPI use, but not when compared with past PPI use (OR: 0.95, 95% CI: 0.38-2.41). Among clopidogrel non-users, current PPI use was associated with an increased risk of recurrent MI (OR: 1.38, 95% CI: 1.18-1.61) when compared with no PPI use.

CONCLUSIONS

The apparent association between recurrent MI and use of PPIs with clopidogrel depends on the design, and is affected by confounding by indication. The association is not present when (un)measured confounding is addressed by design.

EU-ADR healthcare database network vs. spontaneous reporting system database: preliminary comparison of signal detection

The EU-ADR project aims to exploit different European electronic healthcare records (EHR) databases for drug safety signal detection. In this paper we report the preliminary results concerning the comparison of signal detection between EU-ADR network and two spontaneous reporting databases, the Food and Drug Administration and World Health Organization databases. EU-ADR data sources consist of eight databases in four countries (Denmark, Italy, Netherlands, and United Kingdom) that are virtually linked through distributed data network. A custom-built software (Jerboa©) elaborates harmonized input data that are produced locally and generates aggregated data which are then stored in a central repository. Those data are subsequently analyzed through different statistics (i.e. Longitudinal Gamma Poisson Shrinker). As potential signals, all the drugs that are associated to six events of interest (bullous eruptions - BE, acute renal failure - ARF, acute myocardial infarction - AMI, anaphylactic shock - AS, rhabdomyolysis - RHABD, and upper gastrointestinal bleeding - UGIB) have been detected via different data mining techniques in the two systems. Subsequently a comparison concerning the number of drugs that could be investigated and the potential signals detected for each event in the spontaneous reporting systems (SRSs) and EU-ADR network was made. SRSs could explore, as potential signals, a larger number of drugs for the six events, in comparison to EU-ADR (range: 630-3,393 vs. 87-856), particularly for those events commonly thought to be potentially drug-induced (i.e. BE: 3,393 vs. 228). The highest proportion of signals detected in SRSs was found for BE, ARF and AS, while for ARF, and UGIB in EU-ADR. In conclusion, it seems that EU-ADR longitudinal database network may complement traditional spontaneous reporting system for signal detection, especially for those adverse events that are frequent in general population and are not commonly thought to be drug-induced. The methodology for signal detection in EU-ADR is still under development and testing phase.

[Clopidogrel and proton pump inhibitors: insufficient evidence of interaction]

As both proton pump inhibitors (PPIs) and clopidogrel are metabolized by CYP2C19, an enzyme of the cytochrome P450 system, this could lead to drug competition. Recent studies have raised concerns that interaction of PPIs and clopidogrel could reduce the efficacy of clopidogrel and thus increase events such as myocardial infarction. This has resulted in opposing opinions and controversial recommendations. Optimal protection of patients at high risk for cardiovascular events is warranted. On the other hand, optimal gastroprotection for patients at risk for gastrointestinal bleeding is of clinical relevance. Despite the large number of studies, current evidence does not support the existence of an interaction between PPIs and clopidogrel. In agreement with international guidelines the approach of providing this combination therapy to those patients with an accepted indication for gastroprotection and secondary cardiovascular prevention is justified.

Association between calcium channel blockers and gingival hyperplasia

AIM

To study the effect of the dose and type of calcium channel blockers (CCBs) on the risk of gingival hyperplasia and to quantify this association.

METHODS

The study was conducted within the Integrated Primary Care Information Project in The Netherlands. A nested case-control study was designed within a cohort of all patients who were new users of either CCBs or drugs interacting with the renin-angiotensin system (RAS). Cases were all individuals with a validated diagnosis of gingival hyperplasia. Controls were matched on age, gender and index date.

RESULTS

Within the study population, 103 cases of gingival hyperplasia were identified and matched to 7677 controls. The risk of gingival hyperplasia was higher in current users of CCBs [adjusted odds ratio (OR(adj)) 2.2, 95% confidence intervals (95% CI): 1.4-3.4], especially in dihydropyridines (OR(adj) 2.1, 95% CI: 1.3-3.5) and benzothiazepine derivatives (OR(adj) 2.9, 95% CI: 1.3-6.5) than in RAS drug users. The risk increased in patients using more than the recommended daily dose (OR(adj) 3.0, 95% CI: 1.6-5.5) and when the duration of current use was <1 month (OR(adj) 5.2, 95% CI: 2.1-12.6).

CONCLUSION

This study shows that the risk of gingival hyperplasia is twofold higher in current users of CCBs than in users of RAS drugs. The association was dose dependent and the highest for dihydropyridines or benzothiazepine derivates.

Prediction of two month modified Rankin Scale with an ordinal prediction model in patients with aneurysmal subarachnoid haemorrhage

Background

Aneurysmal subarachnoid haemorrhage (aSAH) is a devastating event with a frequently disabling outcome. Our aim was to develop a prognostic model to predict an ordinal clinical outcome at two months in patients with aSAH.

Methods

We studied patients enrolled in the International Subarachnoid Aneurysm Trial (ISAT), a randomized multicentre trial to compare coiling and clipping in aSAH patients.

Several models were explored to estimate a patient's outcome according to the modified Rankin Scale (mRS) at two months after aSAH. Our final model was validated internally with bootstrapping techniques.

Results

The study population comprised of 2,128 patients of whom 159 patients died within 2 months (8%). Multivariable proportional odds analysis identified World Federation of Neurosurgical Societies (WFNS) grade as the most important predictor, followed by age, sex, lumen size of the aneurysm, Fisher grade, vasospasm on angiography, and treatment modality. The model discriminated moderately between those with poor and good mRS scores (c statistic = 0.65), with minor optimism according to bootstrap re-sampling (optimism corrected c statistic = 0.64).

Conclusion

We presented a calibrated and internally validated ordinal prognostic model to predict two month mRS in aSAH patients who survived the early stage up till a treatment decision. Although generalizability of the model is limited due to the selected population in which it was developed, this model could eventually be used to support clinical decision making after external validation.

Trial Registration

International Standard Randomised Controlled Trial, Number ISRCTN49866681

Non-cardiovascular drugs that inhibit hERG-encoded potassium channels and risk of sudden cardiac death

BACKGROUND

Virtually all QTc-prolonging drugs act by blocking the human ether a go-go-related gene (hERG)-encoded potassium channels (hERG channels), whereas not all QTc-prolonging drugs are associated with an increased risk of serious cardiac arrhythmias. This study assessed whether non-cardiovascular hERG channel blockers are associated with an increased risk of sudden cardiac death (SCD) and whether hERG-channel-inhibiting capacity is an indicator of the risk of SCD.

METHODS AND RESULTS

The risk of SCD was studied in the Integrated Primary Care Information database, a longitudinal general practice research database. A case-control study was performed, matched for age, gender and calendar time. Odds ratios were calculated with conditional logistic regression, multivariably adjusted. In addition, the hERG-channel-inhibiting capacity of the different drugs was compared, defined as the effective free therapeutic plasma concentration (ETCP(unbound)) divided by the concentration that inhibits 50% of the potassium channels (IC50), with the risk of SCD. 1424 cases of SCD and 14 443 controls were identified. Current use of hERG channel blockers was associated with an increased risk of SCD. The risk of SCD was significantly increased in users of antipsychotic drugs. Patients using hERG channel blockers with a high ETCP(unbound)/IC50 ratio (≥ 0.033) had a higher risk of SCD than patients using drugs with a low ETCP(unbound)/IC50 ratio (<0.033).

CONCLUSIONS

The current use of hERG channel blockers was associated with an increased risk of SCD in the general population. In addition, drugs with a high hERG-channel-inhibiting capacity had a higher risk of SCD than drugs with a low hERG-channel-inhibiting capacity.

Population-based studies of antithyroid drugs and sudden cardiac death

AIM

Thyroid free T4 is associated with QTc-interval prolongation, which is a risk factor for sudden cardiac death (SCD). Hyperthyroidism has been associated with SCD in case reports, but there are no population-based studies confirming this. The aim was to investigate whether use of antithyroid drugs (as a direct cause or as an indicator of poorly controlled hyperthyroidism) is associated with an increased risk of SCD.

METHODS

We studied the occurrence of SCD in a two-step procedure in two different Dutch populations. First, the prospective population-based Rotterdam Study including 7898 participants (> or =55 years old). Second, we used the Integrated Primary Care Information (IPCI) database, which is a longitudinal general practice research database to see whether we could replicate results from the first study. Drug use at the index date was assessed with prescription information from automated pharmacies (Rotterdam Study) or drug prescriptions from general practices (IPCI). We used a Cox proportional hazards model in a cohort analysis, adjusted for age, gender and use of QTc prolonging drugs (Rotterdam Study) and conditional logistic regression analysis in a case-control analysis, matched for age, gender, practice and calendar time and adjusted for arrhythmia and cerebrovascular ischaemia (IPCI).

RESULTS

In the Rotterdam Study, 375 participants developed SCD during follow-up. Current use of antithyroid drugs was associated with SCD [adjusted hazard ratio 3.9; 95% confidence interval (CI) 1.7, 8.7]. IPCI included 1424 cases with SCD and 14 443 controls. Also in IPCI, current use of antithyroid drugs was associated with SCD (adjusted odds ratio 2.9; 95% CI 1.1, 7.4).

CONCLUSIONS

Use of antithyroid drugs was associated with a threefold increased risk of SCD. Although this might be directly caused by antithyroid drug use, it might be more readily explained by underlying poorly controlled hyperthyroidism, since treated patients who developed SCD still had low thyroid-stimulating hormone levels shortly before death.

Association of community-acquired pneumonia with antipsychotic drug use in elderly patients: a nested case-control study

BACKGROUND

According to safety alerts from the U.S. Food and Drug Administration, pneumonia is one of the most frequently reported causes of death in elderly patients with dementia who are treated with antipsychotic drugs. However, epidemiologic evidence of the association between antipsychotic drug use and pneumonia is limited.

OBJECTIVE

To evaluate whether typical or atypical antipsychotic use is associated with fatal or nonfatal pneumonia in elderly persons.

DESIGN

Population-based, nested case-control study.

SETTING

Dutch Integrated Primary Care Information database.

PATIENTS

Cohort of persons who used an antipsychotic drug, were 65 years or older, and were registered in the IPCI database from 1996 to 2006. Case patients were all persons with incident community-acquired pneumonia. Up to 20 control participants were matched to each case patient on the basis of age, sex, and date of onset.

MEASUREMENTS

Risk for fatal or nonfatal community-acquired pneumonia with atypical and typical antipsychotic use. Antipsychotic exposure was categorized by type, timing, and daily dose, and the association with pneumonia was assessed by using conditional logistic regression.

RESULTS

258 case patients with incident pneumonia were matched to 1686 control participants. Sixty-five (25%) of the case patients died in 30 days, and their disease was considered fatal. Current use of either atypical (odds ratio [OR], 2.61 [95% CI, 1.48 to 4.61]) or typical (OR, 1.76 [CI, 1.22 to 2.53]) antipsychotic drugs was associated with a dose-dependent increase in the risk for pneumonia compared with past use of antipsychotic drugs. Only atypical antipsychotic drugs were associated with an increase in the risk for fatal pneumonia (OR, 5.97 [CI, 1.49 to 23.98]).

LIMITATIONS

Antipsychotic exposure was based on prescription files. Residual confounding due to unmeasured covariates or severity of disease was possible.

CONCLUSION

The use of either atypical or typical antipsychotic drugs in elderly patients is associated in a dose-dependent manner with risk for community-acquired pneumonia.

Genome-wide association study of intracranial aneurysm identifies three new risk loci

Saccular intracranial aneurysms (IAs) are balloon-like dilations of the intracranial arterial wall; their hemorrhage commonly results in severe neurologic impairment and death. We report a second genome-wide association study with discovery and replication cohorts from Europe and Japan comprising 5,891 cases and 14,181 controls with ∼832,000 genotyped and imputed SNPs across discovery cohorts. We identified three new loci showing strong evidence for association with IA in the combined data set, including intervals near RBBP8 on 18q11.2 (OR=1.22, P=1.1×10^-12), STARD13/KL on 13q13.1 (OR=1.20, P=2.5×10^-9) and a gene-rich region on 10q24.32 (OR=1.29, P=1.2×10^-9). We also confirmed prior associations near SOX17 (8q11.23-q12.1; OR=1.28, P=1.3×10^-12) and CDKN2A/B (9p21.3; OR=1.31, P=1.5×10^-22). It is noteworthy that several putative risk genes play a role in cell-cycle progression, potentially affecting proliferation and senescence of progenitor cell populations that are responsible for vascular formation and repair.

Cardiovascular and psychiatric risk profile and patterns of use in patients starting anti-obesity drugs

PURPOSE

Real-life experience with anti-obesity drugs has shown that psychiatric and cardiovascular diseases may be reported as adverse drug reactions. For adequate risk assessment of these drugs knowledge on baseline risks of patients starting anti-obesity drugs and insight in patterns of use is needed. The aim was to assess whether baseline characteristics of patients starting anti-obesity drugs differ from those not being prescribed these drugs, and to study patterns of anti-obesity drug use.

METHODS

A population-based cohort study was conducted in the IPCI database (1995-2007). The index cohort comprised all persons who started an anti-obesity drug. The reference cohort comprised up to six randomly sampled patients from the same GP practice with same index date. Baseline characteristics were assessed for both cohorts. The index cohort was followed for 1 year to study patterns of drug use. Unconditional logistic regression was used to calculate crude odds ratios and 95% confidence intervals.

RESULTS

The index and reference cohort comprised 1471 and 8736 persons, respectively. Both cardiovascular and psychiatric co-morbidities were more prevalent among starters compared to non-starters. 77.7% of the patients stopped using anti-obesity drugs within 90 days. Users of amphetamine-like drugs differed from patients using orlistat or sibutramine, whereas users of orlistat and sibutramine were highly comparable.

CONCLUSIONS

The increased prevalence of co-morbidities constitutes a baseline risk which may translate in higher occurrence of psychiatric and cardiovascular diseases during use of anti-obesity drugs, independent of the drugs. The limited period of use might reduce possible cardiovascular benefits of weight reduction induced by these drugs.

Serum glucose and insulin are associated with QTc and RR intervals in nondiabetic elderly

AIMS

To study whether nondiabetic persons with impaired fasting serum glucose and hyperinsulinemia have QTc/QT interval prolongation and RR interval shortening in the electrocardiogram (ECG), and whether these were associated with an increased risk of sudden cardiac death.

METHODS

This study consisted of two analyses. First, a cross-sectional analysis was used as part of the population-based Rotterdam Study including 1050 men and 1520 women (>or=55 years) without diabetes mellitus. Participants in round 3 of the Rotterdam Study for whom an ECG and fasting serum glucose and fasting insulin measurements were available were eligible for the study. Participants using digoxin or QTc-prolonging drugs and participants with left ventricular hypertrophy and left and right bundle branch block were excluded. The endpoints of the study were the lengths of the QTc, QT, and RR intervals. The associations were examined by means of linear regression analysis. Secondly, in all 6020 participants of the Rotterdam Study with an ECG, the associations between the QTc, QT, and RR intervals and sudden cardiac death were examined by means of Cox regression analysis.

RESULTS

Overall, there was a significant association between impaired fasting serum glucose and the QTc interval with an increase of 2.6 ms (95% confidence interval (CI): 0.3; 5.0) in those with fasting glucose >6 mmol/l. Hyperinsulinemia was also associated with QTc prolongation (3.0 ms (0.8; 5.3)) in those with fasting insulin >or=100 pmol/l. Impaired fasting glucose (IFG) and hyperinsulinemia were significantly associated with a decrease of the RR interval (-33.7 ms (-48.8; -18.6) and -44.4 ms (-58.7; -30.0) respectively). Participants in the fourth quartile of the QTc and QT intervals had a significantly increased risk of sudden cardiac death compared to participants in the first quartile (hazard ratio (HR) 2.87 (95% CI: 2.02-4.06); HR 3.05 (1.99-4.67) respectively). Furthermore, there was a significant inverse association between the fourth quartile of the RR interval compared to the first quartile and the risk of sudden cardiac death (HR 0.49 (0.34-0.80)).

CONCLUSION

In this population-based study, we demonstrated that IFG and hyperinsulinemia are associated with a significantly increased QTc interval and with significant shortening of the RR interval, the latter probably due to an increased sympathetic activity. In addition, we demonstrated that both a prolonged QTc interval and a shortened RR interval are associated with an increased risk of sudden cardiac death.

Role of NFkappaB in an animal model of complex regional pain syndrome-type I (CRPS-I)

NFkappaB is involved in several pathogenic mechanisms that are believed to underlie the complex regional pain syndrome (CRPS), including ischemia, inflammation and sensitization. Chronic postischemia pain (CPIP) has been developed as an animal model that mimics the symptoms of CRPS-I. The possible involvement of NFkappaB in CRPS-I was studied using CPIP rats. Under sodium pentobarbital anesthesia, a tourniquet was placed around the rat left ankle joint, producing 3 hours of ischemia, followed by rapid reperfusion (IR injury). NFkappaB was measured in nuclear extracts of muscle and spinal cord tissue using ELISA. Moreover, the anti-allodynic (mechanical and cold) effect was tested for systemic, intrathecal, or intraplantar treatment with the NFkappaB inhibitor pyrrolidine dithiocarbamate (PDTC). At 2 and 48 hours after IR injury, NFkappaB was elevated in muscle and spinal cord of CPIP rats compared to shams. At 7 days, NFkappaB levels were normalized in muscle, but still elevated in spinal cord tissue. Systemic PDTC treatment relieved mechanical and cold allodynia in a dose-dependent manner, lasting for at least 3 hours. Intrathecal-but not intraplantar-administration also relieved mechanical allodynia. The results suggest that muscle and spinal NFkappaB plays a role in the pathogenesis of CPIP and potentially of human CRPS.

PERSPECTIVE

Using the CPIP model, we demonstrate that NFkappaB is involved in the development of allodynia after a physical injury (ischemia and reperfusion) without direct nerve trauma. Since CPIP animals exhibit many features of human CRPS-I, this observation indicates a potential role for NFkappaB in human CRPS.

The association of serum testosterone levels and ventricular repolarization

It is assumed that testosterone is an important regulator of gender-related differences in ventricular repolarization. Therefore, our aim was to study whether serum levels of testosterone are associated with QTc, QT and RR interval variation. Setting: two independent population-based cohort studies. Participants: 445 male participants (≥55 years) from the Rotterdam study cohort and 1,428 male participants from the study of health in Pomerania (SHIP) with an electrocardiogram who were randomly sampled for assessment of serum testosterone at baseline, after exclusion of participants with testosterone altering drugs, QTc prolonging drugs or dig(it)oxin, left ventricular hypertrophy and left and right bundle branch block. Endpoints: length of the QTc, QT and RR intervals. Analysis: linear regression model, adjusted for the two individual studies and a pooled analysis of both studies. The pooled analysis of the Rotterdam study and SHIP showed that the QTc interval gradually decreased among the tertiles (P value for trend 0.024). The third tertile of serum testosterone was associated with a lower QTc interval compared to the first tertile [−3.4 ms (−6.5; −0.3)]. However, the third tertile of serum testosterone was not associated with a lower QT interval compared to the first tertile [−0.7 ms (−3.1; 1.8)]. The RR interval gradually increased among the tertiles (P value for trend 0.002) and the third tertile of serum testosterone showed an increased RR interval compared to the first tertile [33.5 ms (12.2; 54.8)]. In the pooled analysis of two population-based studies, serum testosterone levels were not associated with the QT interval, which could be due to a lack of power. Lower QTc intervals in men with higher serum testosterone levels could be due to the association of serum testosterone with prolongation of the RR interval.

Comparison of antiepileptic drug prescribing in children in three European countries

PURPOSE

Antiepileptic drug (AED) use in young people is increasing. However, evidence of its use at a multinational level is limited. This study aims to characterize AED prescribing in the young in three European countries and to assess the capacity of drug safety surveillance.

METHODS

A retrospective cohort study was conducted in 2001-2005 using primary care databases: PEDIANET (Italy, 0-11 years), IPCI (The Netherlands, 0-18 years), and IMS Disease Analyzer (United Kingdom, 0-18 years). Prescribing prevalence was calculated by country, patient age, and drug type.

RESULTS

In 2005, AED prevalence in children (0-11 years) was highest in Italy [3.9 subjects/1,000 person-years (PY)] followed by the United Kingdom (3.0 subjects/1,000 PY) and The Netherlands (2.2 subjects/1,000 PY). Over the study period, prescribing prevalence in 0-11 year olds was stable in all countries. In contrast, a steady rise of AED prevalence was observed in adolescents (12-18 years) in the United Kingdom (p = 0.0003) but not in The Netherlands (p = 0.88). All countries showed a slight increase in prevalence for newer AEDs. Simultaneously, the prevalence of conventional AEDs decreased in The Netherlands and Italy, but not in the United Kingdom. In 2005, lamotrigine use was highest in The Netherlands and the United Kingdom, whereas topiramate was favored in Italy.

DISCUSSION

In Europe, conventional AEDs are still the main treatment choice for children with epilepsy, and the use of newer AEDs remains low. Our study highlights a lack of research capacity to conduct multinational AED safety studies in children. Further work should explore large databases and other health care settings to meet these research needs.

Incidence of facial pain in the general population

Facial pain has a considerable impact on quality of life. Accurate incidence estimates in the general population are scant. The aim was therefore to estimate the incidence rate (IR) of trigeminal neuralgia (TGN), postherpetic neuralgia (PHN), cluster headache (CH), occipital neuralgia (ON), local neuralgia (LoN), atypical facial pain (AFP), glossopharyngeal neuralgia (GPN) and paroxysmal hemicrania (PH) in the Netherlands. In the population-based Integrated Primary Care Information (IPCI) medical record database potential facial pain cases were identified from codes and narratives. Two medical doctors reviewed medical records, questionnaires from general practitioners and specialist letters using criteria of the International Association for the Study of Pain. A pain specialist arbitrated if necessary and a random sample of all cases was evaluated by a neurologist. The date of onset was defined as date of first specific symptoms. The IR was calculated per 100,000PY. Three hundred and sixty-two incident cases were ascertained. The overall IR [95% confidence interval] was 38.7 [34.9-42.9]. It was more common among women compared to men. Trigeminal neuralgia and cluster headache were the most common forms among the studied diseases. Paroxysmal hemicrania and glossopharyngeal neuralgia were among the rarer syndromes. The IR increased with age for all diseases except CH and ON, peaking in the 4th and 7th decade, respectively. Postherpetic neuralgia, CH and LoN were more common in men than women. From this we can conclude that facial pain is relatively rare, although more common than estimated previously based on hospital data.

Referral and treatment patterns for complex regional pain syndrome in the Netherlands

BACKGROUND

Patients with complex regional pain syndrome (CRPS) are seen and treated by a variety of physicians. The present study aims to describe referral and treatment patterns for CRPS patients in the Netherlands.

METHODS

Patients, who were selected (1996-2005) from an electronic general practice (GP) database (Integrated Primary Care Information Project), were invited for study participation, involving diagnosis verification (International Association for the Study of Pain criteria) and assessment of referrals and treatment through information retrieved from GP journals, patients' questionnaires, pharmacy dispensing lists and specialist letters if available.

RESULTS

One hundred and two patients were included. Sixty-one percent had presented first at the GP, while 80% subsequently consulted one or more medical specialists, most frequently an anesthetist (55% of the cases) or a specialist in rehabilitation medicine (41%). Over 90% of the patients received oral or topical pharmacotherapy, 45% received intravenous therapy, 89% received non-invasive therapy (i.e. physiotherapy) and 18% received nerve blocks. Analgesics and free radical scavengers were administered early during CRPS, while vasodilating drugs and drugs against neuropathic pain (antidepressants and anti-epileptics) were administered later on. Pharmacotherapy was usually initiated by a medical specialist.

CONCLUSION

The Dutch treatment guidelines, issued in 2006, recommend free radical scavenger prescription (plus physiotherapy) as the initial treatment step for CRPS. Until 2005 only half of the patients received a scavenger within 3 months after disease onset, and the majority presents first at the GP, in particular GPs may be encouraged to initiate treatment with scavengers, while waiting for the results of further specialist consultation.

Withdrawal of statins and risk of subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Vascular endothelium, which can be affected by statins, is believed to play a substantial role in subarachnoid hemorrhage (SAH). Our objective was to estimate the association between use and withdrawal of statins and the risk of SAH.

METHODS

We conducted a population-based case-control study within the PHARMO database. A case was defined as a person hospitalized for SAH (ICD-9-CM code 430) in the period January 1, 1998 to December 31, 2006. Ten randomly chosen controls were matched to each case on age, gender, and calendar date.

RESULTS

During the study period 1004 incident cases of SAH were identified. Current use of statins did not significantly decrease the risk of SAH (OR=0.77, 95% CI 0.55 to 1.07). The odds ratio for recent withdrawal compared to nonusers was 1.62 (95% CI 0.96 to 2.73). Compared to current use, recent withdrawal was associated with an increased risk of SAH (OR=2.34, 95% CI 1.35 to 4.05). Interaction analysis showed that the effect of statin withdrawal was highest in patients who had also recently stopped antihypertensive drugs (OR=6.77, 95% CI 2.10 to 21.8).

CONCLUSIONS

Current use of statins seems to lower the risk of SAH, although the reduction was not significant in new users. Statin withdrawal increased the risk of SAH by a factor 2, even more in patients who had also recently stopped their antihypertensive treatment.

Databases for pediatric medicine research in Europe--assessment and critical appraisal

PURPOSE

To identify and describe European health care databases that can be used for pediatric pharmacoepidemiological research.

METHODS

A web-based survey was conducted among all European databases that were listed on the website of the International Society of Pharmacoepidemiology (ISPE) and/or known by an expert group. The survey comprised of questions regarding (a) the nature of the database, (b) database size, (c) demographic, clinical and drug related data provided, (d) cost, and (e) accessibility of the database.

RESULTS

A total of 25 data sources from 12 European countries were identified and invited to participate in the survey. Responses were obtained from 21 (84%) databases located in 10 different European countries. Seventeen databases were included in the assessment comprising a total of at least 9 million children aged 0-18 years. The majority of databases are based on outpatient data and all keep either prescription or drug dispensing data. Ten databases are based on electronic patient records from primary care physicians and five databases are predominantly claims oriented. Three databases do not belong to either of the above mentioned categories. Almost all of the databases can be used for pediatric drug utilization studies. For drug safety studies it is more appropriate to use electronic patient record databases because of the available clinical information and the potential to obtain additional information.

CONCLUSIONS

There are many European healthcare databases providing an enormous potential for pediatric pharmacoepidemiological research. Future research should focus on methods to bring data from different databases together to use the full capacity effectively.

Estrogens and the risk of complex regional pain syndrome (CRPS)

OBJECTIVE

Since complex regional pain syndrome (CRPS) shows a clear female predominance, we investigated the association between the cumulative as well as current exposure to estrogens, and CRPS.

METHODS

A population-based case-control study was conducted in the Integrated Primary Care Information (IPCI) project in the Netherlands. Cases were identified from electronic records (1996-2005) and included if they were confirmed during a visit (using International Association for the Study of Pain Criteria), or had been diagnosed by a specialist. Controls were matched to cases on gender, age, calendar time, and injury. Measures of cumulative endogenous estrogen exposure were obtained by questionnaire and included age of menarche and menopause, menstrual life, and cumulative months of pregnancy and breast-feeding. Current estrogen exposure at CRPS onset was retrieved from the electronic medical records and determined by current pregnancy or by the use of oral contraceptive (OC) drugs or hormonal replacement therapy (HRT).

RESULTS

Hundred and forty-three female cases (1493 controls) were included in analyses on drug use and pregnancies, while cumulative endogenous estrogen exposure was studied in 53 cases (58 controls) for whom questionnaire data were available. There was no association between CRPS and either cumulative endogenous estrogen exposure, OC, or HRT use. CRPS onset was increased during the first 6 months after pregnancy (OR: 5.6, 95%CI: 1.0-32.4), although based on small numbers.

DISCUSSION

We did not find an association between CRPS onset and cumulative endogenous estrogen exposure or current OC or HRT use, but more powered studies are needed to exclude potential minor associations.

The EU-ADR project: preliminary results and perspective

The EU-ADR project aims to exploit different European electronic healthcare records (EHR) databases for drug safety signal detection. In this paper we describe the project framework and the preliminary results.

METHODS

As first step we created a ranked list of the events that are deemed to be important in pharmacovigilance as mining on all possible events was considered to unduly increase the number of spurious signals. All the drugs that are potentially associated to these events will be detected via data mining techniques. Data sources are eight 8 databases in four countries (Denmark, Italy, the Netherlands, and the United Kingdom) that are virtually linked through harmonisation of input data followed by local elaboration of input data through custom-built software (Jerboa). All the identified drug-event associations (signals) will be thereafter biologically substantiated and epidemiologically validated. To date, only Upper gastrointestinal bleeding (UGIB) event has been used to test the ability of the system in signal detection.

RESULTS

An initial ranked list comprising 23 adverse events was identified. The top-ranking events were: cutaneous bullous eruptions, acute renal failure, acute myocardial infarction, anaphylactic shock, and rhabdomyolysis. Regarding the UGIB test, a total of 48,016 first-ever episodes were identified. The age-standardized incidence rates of UGIB varied between 40-100/100,000 person-years depending on country and type of healthcare database. A statistically significant association between use of NSAIDs and UGIB was detected in all of the databases.

CONCLUSION

a dynamic ranked list of 23 adverse drug events judged as important in pharmacovigilance was created to permit focused data mining. Preliminary results on the UGIB event detection demonstrate the feasibility of harmonizing various health care databases in different European countries through a distributed network approach.

Drug use in children: cohort study in three European countries

OBJECTIVE

To provide an overview of drug use in children in three European countries.

DESIGN

Retrospective cohort study, 2000-5.

SETTING

Primary care research databases in the Netherlands (IPCI), United Kingdom (IMS-DA), and Italy (Pedianet).

PARTICIPANTS

675 868 children aged up to 14 (Italy) or 18 (UK and Netherlands).

MAIN OUTCOME MEASURE

Prevalence of use per year calculated by drug class (anatomical and therapeutic). Prevalence of "recurrent/chronic" use (three or more prescriptions a year) and "non-recurrent" or "acute" use (less than three prescriptions a year) within each therapeutic class. Descriptions of the top five most commonly used drugs evaluated for off label status within each anatomical class.

RESULTS

Three levels of drug use could be distinguished in the study population: high (>10/100 children per year), moderate (1-10/100 children per year), and low (<1/100 children per year). For all age categories, anti-infective, dermatological, and respiratory drugs were in the high use group, whereas cardiovascular and antineoplastic drugs were always in the low use group. Emollients, topical steroids, and asthma drugs had the highest prevalence of recurrent use, but relative use of low prevalence drugs was more often recurrent than acute. In the top five highest prevalence drugs topical inhaled and systemic steroids, oral contraceptives, and topical or systemic antifungal drugs were most commonly used off label.

CONCLUSION

This overview of outpatient paediatric prescription patterns in a large European population could provide information to prioritise paediatric therapeutic research needs.

A novel programme to evaluate and communicate 10-year risk of CHD reduces predicted risk and improves patients' modifiable risk factor profile

AIMS

We assessed whether a novel programme to evaluate/communicate predicted coronary heart disease (CHD) risk could lower patients' predicted Framingham CHD risk vs. usual care.

METHODS

The Risk Evaluation and Communication Health Outcomes and Utilization Trial was a prospective, controlled, cluster-randomised trial in nine European countries, among patients at moderate cardiovascular risk. Following baseline assessments, physicians in the intervention group calculated patients' predicted CHD risk and were instructed to advise patients according to a risk evaluation/communication programme. Usual care physicians did not calculate patients' risk and provided usual care only. The primary end-point was Framingham 10-year CHD risk at 6 months with intervention vs. usual care.

RESULTS

Of 1103 patients across 100 sites, 524 patients receiving intervention, and 461 receiving usual care, were analysed for efficacy. After 6 months, mean predicted risks were 12.5% with intervention, and 13.7% with usual care [odds ratio = 0.896; p = 0.001, adjusted for risk at baseline (17.2% intervention; 16.9% usual care) and other covariates]. The proportion of patients achieving both blood pressure and low-density lipoprotein cholesterol targets was significantly higher with intervention (25.4%) than usual care (14.1%; p < 0.001), and 29.3% of smokers in the intervention group quit smoking vs. 21.4% of those receiving usual care (p = 0.04).

CONCLUSIONS

A physician-implemented CHD risk evaluation/communication programme improved patients' modifiable risk factor profile, and lowered predicted CHD risk compared with usual care. By combining this strategy with more intensive treatment to reduce residual modifiable risk, we believe that substantial improvements in cardiovascular disease prevention could be achieved in clinical practice.