For which clinical rules do doctors want decision support, and why? A survey of Dutch general practitioners.

Despite the promise of decision support for improving care, alerts are often overridden or ignored. We evaluated Dutch general practitioners' intention to accept decision support in a proposed implementation based on clinical rules regarding care for elderly patients, and their reasons for wanting or not wanting support. We developed a survey based on literature and structured interviews and distributed it to all doctors who would receive support in the proposed implementation (n = 43), of which 65 percent responded. The survey consisted of six questions for each of 20 clinical rules. Despite concerns about interruption, doctors tended to choose more interruptive forms of support. Doctors wanted support when they felt the rule represented minimal care, perceived a need to improve care, and felt responsible for the action and that they might forget to perform the action; doctors declined support due to feeling that it was unnecessary and due to concerns about interruption.

Is frequent attendance of longer duration related to less transient episodes of care? A retrospective analysis of transient and chronic episodes of care.

OBJECTIVES: Frequent attenders (FAs) suffer more and consult general practitioners (GPs) more often for chronic physical and psychiatric illnesses, social difficulties and distress than non-FAs. However, it is unclear to what extent FAs present transient episodes of care (TECs) compared with non-FAs. DESIGN: Retrospective analysis of all episodes of care (ECs) in 15 116 consultations in 1 year. Reasons for encounter (RFEs) linked to patients' problem lists were defined as chronic ECs (CECs), other episodes as TECs. SETTING: 1 Dutch urban primary healthcare centre served by 5 GPs. PARTICIPANTS: All 5712 adult patients were enlisted between 2007 and 2009. FAs were patients whose attendance rate ranked within the top decile of their sex and age group in at least one of the years between 2007 and 2009. OUTCOME MEASURES: Number of RFEs linked to TECs/CECs for non-FAs and 1-year (1yFAs), 2-year (2yFAs) and 3-year FAs (3yFAs), and the adjusted effect of frequent attendance of different duration on the number of TECs. RESULTS: The average number of RFEs linked to TECs (non-FAs 1.4; 3yFAs 7.3) and to CECs (non-FAs 0.9; 3yFAs 6.2) increased substantially with the duration of frequent attendance. The ratio of TECs to all ECs differed little for FAs (52-54%) and non-FAs (64%). Compared with non-FAs, the adjusted additional number of TECs was 3.4 (95% CI 3.2 to 3.7, 1yFAs), 6.6 (95% CI 6.1 to 7.0, 2yFAs) and 9.4 (95% CI 8.8 to 10.1, 3yFAs). CONCLUSIONS: FAs present more TECs and CECs with longer duration of frequent attendance. The constant ratio of TECs might be a sign of a low threshold for FAs to consult their GP. The large numbers of TECs in FAs might be associated with their high level of anxiety and low mastery. The consultation pattern of FAs may best be characterised by describing both TECs and CECs.

Why do they keep coming back? Psychosocial etiology of persistence of frequent attendance in primary care: a prospective cohort study.

BACKGROUND: Patients who visit their General Practitioner (GP) very frequently over extended periods of time often have multimorbidity and are costly in primary and specialist healthcare. We investigated the impact of patient-level psychosocial and GP-level factors on the persistence of frequent attendance (FA) in primary care. METHODS: Two-year prospective cohort study in 623 incident adult frequent attenders (>90th attendance centile; age and sex-adjusted) in 2009. Information was collected through questionnaires (patients, GPs) and GPs' patient data. We used multilevel, ordinal logistic regression analysis, controlling for somatic illness and demographic factors with FA in 2010 and/or 2011 as the outcome. RESULTS: Other anxiety (odds ratio (OR) 2.00; 95% confidence interval from 1.29 to 3.10) over 3years and the number of life events in 3years (OR 1.06; 1.01-1.10 per event; range of 0 to 12) and, at baseline, panic disorder (OR 5.40; 1.67-17.48), other anxiety (OR 2.78; 1.04-7.46), illness behavior (OR 1.13; 1.05-1.20 per point; 28-point scale) and lack of mastery (OR 1.08; 1.01-1.15 per point; 28-point scale) were associated with persistence of FA. We found no evidence of synergistic effects of somatic, psychological and social problems. We found no strong evidence of effects of GP characteristics. CONCLUSION: Panic disorder, other anxiety, negative life events, illness behavior and lack of mastery are independently associated with persistence of frequent attendance. Effective intervention at these factors, apart from their intrinsic benefits to these patients, may reduce attendance rates, and healthcare expenditures in primary and specialist care.

Atrial fibrillation is an independent risk factor for ventricular fibrillation: a large-scale population-based case-control study.

BACKGROUND: Atrial fibrillation (AF) is associated with sudden cardiac death. We aimed to study whether AF is associated with ventricular fibrillation (VF), the most common cause of sudden cardiac death and whether this association is independent of confounders, ie, concomitant disease, use of antiarrhythmic or QT-prolonging drugs, and acute myocardial infarction. METHODS AND RESULTS: We performed a community-based case-control study. Cases were patients with out-of-hospital cardiac arrest because of ECG-documented VF. Controls were age-/sex-matched non-VF subjects from the community. VF risk in AF patients was studied by means of (conditional) logistic regression, adjusting for all available confounders. We studied 1397 VF cases and 3474 controls. AF occurred in 215 cases (15.4%) and 90 controls (2.6%). AF was associated with a 3-fold increased risk of VF (adjusted odds ratio, 3.1 [2.1-4.5]). VF risk in AF cases was increased to the same extent across all age/sex groups and in AF cases who had no comorbidity (adjusted odds ratio 3.0 [1.6-5.5]) or used no confounding drugs (antiarrhythmics, 2.4 [1.4-4.3]; QT-prolonging drugs, 3.1 [1.8-5.4]). VF risk was similarly increased in AF cases with acute myocardial infarction-related VF (adjusted odds ratio 2.6 [1.4-4.8]), and those with non-acute myocardial infarction-related VF (adjusted odds ratio 4.3 [1.9-10.1]). CONCLUSIONS: AF is independently associated with a 3-fold increased risk of VF. Comorbidity, use of antiarrhythmic or QT-prolonging drugs, or acute myocardial infarction does not fully account for this increased risk.

Carbohydrate-related enzymes of important Phytophthora plant pathogens.

Carbohydrate-Active enZymes (CAZymes) form particularly interesting targets to study in plant pathogens. Despite the fact that many CAZymes are pathogenicity factors, oomycete CAZymes have received significantly less attention than effectors in the literature. Here we present an analysis of the CAZymes present in the Phytophthora infestans, Ph. ramorum, Ph. sojae and Pythium ultimum genomes compared to growth of these species on a range of different carbon sources. Growth on these carbon sources indicates that the size of enzyme families involved in degradation of cell-wall related substrates like cellulose, xylan and pectin is not always a good predictor of growth on these substrates. While a capacity to degrade xylan and cellulose exists the products are not fully saccharified and used as a carbon source. The Phytophthora genomes encode larger CAZyme sets when compared to Py. ultimum, and encode putative cutinases, GH12 xyloglucanases and GH10 xylanases that are missing in the Py. ultimum genome. Phytophthora spp. also encode a larger number of enzyme families and genes involved in pectin degradation. No loss or gain of complete enzyme families was found between the Phytophthora genomes, but there are some marked differences in the size of some enzyme families.

Incidence of calcaneal apophysitis in the general population.

BACKGROUND: Calcaneal apophysitis, or Sever's disease, is a traction apophysitis. It is a frequent cause of heel pain in children. Knowledge about the exact incidence of calcaneal apophysitis in the general population, however, is lacking. DESIGN: Cross-sectional study. METHODS: From 34 general practices, records of patients between 6 and 17 years old, visiting the general practitioner (GP), were analysed. Diagnoses of calcaneal apophysitis were counted using computerised registration networks of GPs in 2008, 2009 and 2010. RESULTS: There were 16,383 SOAP files searched and a number of 61 children with calcaneal apophysitis were established over the years 2010, 2009 and 2008, showing an incidence of 3.7 in 1,000 registered patients. CONCLUSION: This is the first report on incidence rates of calcaneal apophysitis in general practice. With an incidence of 3.7 in 1,000 registered patients, it is a common pathologic entity, which requires more research on pathophysiology and therapy. The actual incidence may even be higher due the strict inclusion criteria of this study.

Morbidity and doctor characteristics only partly explain the substantial healthcare expenditures of frequent attenders: a record linkage study between patient data and reimbursements data.

BACKGROUND: Frequently attending patients to primary care (FA) are likely to cost more in primary care than their non-frequently attending counterparts. But how much is spent on specialist care of FAs? We describe the healthcare expenditures of frequently attending patients during 1, 2 or 3 years and test the hypothesis that additional costs can be explained by FAs' combined morbidity and primary care physicians' characteristics. METHODS: Record linkage study. Pseudonymised clinical data from the medical records of 16 531 patients from 39 general practices were linked to healthcare insurer's reimbursements data. Main outcome measures were all reimbursed primary and specialist healthcare costs between 2007 and 2009. Multilevel linear regression analysis was used to quantify the effects of the different durations of frequent attendance on three-year total healthcare expenditures in primary and specialist care, while adjusting for age, sex, morbidities and for primary care physicians characteristics. Primary care physicians' characteristics were collected through administrative data and a questionnaire. RESULTS: Unadjusted mean 3-year expenditures were 5044 and 15 824 Euros for non-FAs and three-year-FAs, respectively. After adjustment for all other included confounders, costs both in primary and specialist care remained substantially higher and increased with longer duration of frequent attendance. As compared to non-FAs, adjusted mean expenditures were 1723 and 5293 Euros higher for one-year and three-year FAs, respectively. CONCLUSIONS: FAs of primary care give rise to substantial costs not only in primary, but also in specialist care that cannot be explained by their multimorbidity. Primary care physicians' working styles appear not to explain these excess costs. The mechanisms behind this excess expenditure remain to be elucidated.

Predictability of persistent frequent attendance in primary care: a temporal and geographical validation study.

BACKGROUND: Frequent attenders are patients who visit their general practitioner exceptionally frequently. Frequent attendance is usually transitory, but some frequent attenders become persistent. Clinically, prediction of persistent frequent attendance is useful to target treatment at underlying diseases or problems. Scientifically it is useful for the selection of high-risk populations for trials. We previously developed a model to predict which frequent attenders become persistent. AIM: To validate an existing prediction model for persistent frequent attendance that uses information solely from General Practitioners' electronic medical records. METHODS: We applied the existing model (N = 3,045, 2003-2005) to a later time frame (2009-2011) in the original derivation network (N = 4,032, temporal validation) and to patients of another network (SMILE; 2007-2009, N = 5,462, temporal and geographical validation). Model improvement was studied by adding three new predictors (presence of medically unexplained problems, prescriptions of psychoactive drugs and antibiotics). Finally, we derived a model on the three data sets combined (N = 12,539). We expressed discrimination using histograms of the predicted values and the concordance-statistic (c-statistic) and calibration using the calibration slope (1 = ideal) and Hosmer-Lemeshow tests. RESULTS: The existing model (c-statistic 0.67) discriminated moderately with predicted values between 7.5 and 50 percent and c-statistics of 0.62 and 0.63, for validation in the original network and SMILE network, respectively. Calibration (0.99 originally) was better in SMILE than in the original network (slopes 0.84 and 0.65, respectively). Adding information on the three new predictors did not importantly improve the model (c-statistics 0.64 and 0.63, respectively). Performance of the model based on the combined data was similar (c-statistic 0.65). CONCLUSION: This external validation study showed that persistent frequent attenders can be prospectively identified moderately well using data solely from patients' electronic medical records.

Attitudes and experience of Dutch general practitioners regarding computerized clinical decision support.

UNLABELLED: Dutch general practices have a high adoption rate for computerized patient records and clinical decision support. We sought to measure the attitudes and experience of Dutch general practitioners towards clinical decision support. METHODS: A preliminary survey was created based on questions from published surveys, modified with the results of interviews. The final web-based survey was administered to 43 general practitioners in a practice area where a decision support implementation is planned. RESULTS: Thirty general practitioners (70%) completed the survey. Most felt that decision support is a good idea (23/30), although fewer reported positive experience with decision support (10/30). Participants were supportive of rules and guidelines, but commonly had the sense that there were too many alerts. CONCLUSION: Dutch clinicians are positive about decision support, but future efforts should try to reduce the perception of overload, for example by ensuring that alerts are relevant and choosing less interruptive forms of notification for less severe alerts.

Prevalence and medical risks of body packing in the Amsterdam area.

AIM: Body packing is a way to deliver packets of drugs across international borders by ingestion. The aim of the study was to provide an estimate of the medical risks of body packing, describe predictors for hospital referral in detained body packers and provide an estimate for the prevalence of body packing in the Amsterdam area. METHODS: From May 2007 to December 2008, we studied medical records of body packers immediately detained after arrival at Amsterdam Schiphol airport, hospital records of both detained body packers and self-referrers at two emergency departments of hospitals in Amsterdam and records kept by forensic physicians in charge of post-mortem examinations of all unnatural deaths in the area (years 2005-2009). RESULTS: In airport detainees, the hospital referral rate was 4.2% (30 out of 707 detained body packers), the surgery rate was 1.3%. Significant predictors of hospital referral were delayed production of drug packets after arrest, cigarette smoking and country of departure. The surgery rate in self-referrers was comparable to the rate observed in those referred from the detention centre to hospital (30% vs. 31%). In addition, from 2005 to 2009, 20 proven cases of lethal body packing were identified. Based on our data, it is estimated that minimally 38% of all incoming body packers were missed by airport controls. CONCLUSION: The risk for lethal complications due to body packing is low on a population basis and comparable to other studies. This also applies for the hospital referral and surgery rates found in this study. Cigarette smoking has not yet been described in the literature as a potential predictor for hospital referral in detained body packers and therefore deserves attention in future research. A substantial fraction of body packers manages to remain undiscovered.

Epilepsy is a risk factor for sudden cardiac arrest in the general population.

BACKGROUND: People with epilepsy are at increased risk for sudden death. The most prevalent cause of sudden death in the general population is sudden cardiac arrest (SCA) due to ventricular fibrillation (VF). SCA may contribute to the increased incidence of sudden death in people with epilepsy. We assessed whether the risk for SCA is increased in epilepsy by determining the risk for SCA among people with active epilepsy in a community-based study. METHODS AND RESULTS: This investigation was part of the Amsterdam Resuscitation Studies (ARREST) in the Netherlands. It was designed to assess SCA risk in the general population. All SCA cases in the study area were identified and matched to controls (by age, sex, and SCA date). A diagnosis of active epilepsy was ascertained in all cases and controls. Relative risk for SCA was estimated by calculating the adjusted odds ratios using conditional logistic regression (adjustment was made for known risk factors for SCA). We identified 1019 cases of SCA with ECG-documented VF, and matched them to 2834 controls. There were 12 people with active epilepsy among cases and 12 among controls. Epilepsy was associated with a three-fold increased risk for SCA (adjusted OR 2.9 [95%CI 1.1-8.0.], p=0.034). The risk for SCA in epilepsy was particularly increased in young and females. CONCLUSION: Epilepsy in the general population seems to be associated with an increased risk for SCA.

The genus Phytophthora anno 2012.

Plant diseases caused by Phytophthora species will remain an ever increasing threat to agriculture and natural ecosystems. Phytophthora literally means plant destroyer, a name coined in the 19th century by Anton de Bary when he investigated the potato disease that set the stage for the Great Irish Famine. Phytophthora infestans, the causal agent of potato late blight, was the first species in a genus that at present has over 100 recognized members. In the last decade, the number of recognized Phytophthora species has nearly doubled and new species are added almost on a monthly basis. Here we present an overview of the 10 clades that are currently distinguished within the genus Phytophthora with special emphasis on new species that have been described since 1996 when Erwin and Ribeiro published the valuable monograph 'Phytophthora diseases worldwide' (35).

Phytophthora gemini sp. nov., a new species isolated from the halophilic plant Zostera marina in the Netherlands.

Eight strains belonging to the Oomycete genus Phytophthora were isolated from Zostera marina (seagrass) in The Netherlands over the past 25 y. Based on morphology, isozymes, temperature-growth relationships and ITS sequences, these strains were found to belong to two different Phytophthora species. Five strains, four of them isolated from rotting seeds and one isolated from decaying plants, could not be assigned to a known species and hence belong to a new species for which we propose the name Phytophthora gemini sp. nov. Three strains were isolated from decaying plants and were identified as Phytophthora inundata, thereby expanding the known habitat range of this species from fresh to brackish-saline areas. The possible role of both Phytophthora species in the decline of Z. marina in The Netherlands and the evolutionary significance of the presence of Phytophthora species in marine environments are discussed.

Usefulness of primary care electronic networks to assess the incidence of chlamydia, diagnosed by general practitioners.

BACKGROUND: Chlamydia is the most common curable sexually transmitted infection (STI) in the Netherlands. The majority of chlamydia diagnoses are made by general practitioners (GPs). Baseline data from primary care will facilitate the future evaluation of the ongoing large population-based screening in the Netherlands. The aim of this study was to assess the usefulness of electronic medical records for monitoring the incidence of chlamydia cases diagnosed in primary care in the Netherlands. METHODS: In the electronic records of two regional and two national networks, we identified chlamydia diagnoses by means of ICPC codes (International Classification of Primary Care), laboratory results in free text and the prescription of antibiotics. The year of study was 2007 for the two regional networks and one national network, for the other national network the year of study was 2005. We calculated the incidence of diagnosed chlamydia cases per sex, age group and degree of urbanization. RESULTS: A large diversity was observed in the way chlamydia episodes were coded in the four different GP networks and how easily information concerning chlamydia diagnoses could be extracted. The overall incidence ranged from 103.2/100,000 to 590.2/100,000. Differences were partly related to differences between patient populations. Nevertheless, we observed similar trends in the incidence of chlamydia diagnoses in all networks and findings were in line with earlier reports. CONCLUSIONS: Electronic patient records, originally intended for individual patient care in general practice, can be an additional source of data for monitoring chlamydia incidence in primary care and can be of use in assessing the future impact of population-based chlamydia screening programs. To increase the usefulness of data we recommend more efforts to standardize registration by (specific) ICPC code and laboratory results across the existing GP networks.

Diabetes care: reasons for missing HbA1c measurements in general practice.

BACKGROUND: Glycated haemoglobin (HbA1c) is often used as one of the indicators to measure the quality of diabetes care. Complete registration is difficult to obtain. This study investigated the reasons for missing HbA1c measurements. FINDINGS: HbA1c measurements for 1485 patients with diabetes mellitus type 2 who were attended by 19 general practitioners at 4 primary care health centres in south-east Amsterdam were studied. HbA1c measurements were missing for 356 (23.9%) of the patients. The main reason stated in 50% of the cases was that the patient was under specialized care. CONCLUSIONS: The general practitioners provided multiple reasons for the missing HbA1c measurements. This study provides insight into why HbA1c measurements were not present in the patients' electronic medical record.

DNA barcoding of oomycetes with cytochrome c oxidase subunit I and internal transcribed spacer.

Oomycete species occupy many different environments and many ecological niches. The genera Phytophthora and Pythium for example, contain many plant pathogens which cause enormous damage to a wide range of plant species. Proper identification to the species level is a critical first step in any investigation of oomycetes, whether it is research driven or compelled by the need for rapid and accurate diagnostics during a pathogen outbreak. The use of DNA for oomycete species identification is well established, but DNA barcoding with cytochrome c oxidase subunit I (COI) is a relatively new approach that has yet to be assessed over a significant sample of oomycete genera. In this study we have sequenced COI, from 1205 isolates representing 23 genera. A comparison to internal transcribed spacer (ITS) sequences from the same isolates showed that COI identification is a practical option; complementary because it uses the mitochondrial genome instead of nuclear DNA. In some cases COI was more discriminative than ITS at the species level. This is in contrast to the large ribosomal subunit, which showed poor species resolution when sequenced from a subset of the isolates used in this study. The results described in this paper indicate that COI sequencing and the dataset generated are a valuable addition to the currently available oomycete taxonomy resources, and that both COI, the default DNA barcode supported by GenBank, and ITS, the de facto barcode accepted by the oomycete and mycology community, are acceptable and complementary DNA barcodes to be used for identification of oomycetes.

Genome sequence of the necrotrophic plant pathogen Pythium ultimum reveals original pathogenicity mechanisms and effector repertoire.

BACKGROUND: Pythium ultimum is a ubiquitous oomycete plant pathogen responsible for a variety of diseases on a broad range of crop and ornamental species. RESULTS: The P. ultimum genome (42.8 Mb) encodes 15,290 genes and has extensive sequence similarity and synteny with related Phytophthora species, including the potato blight pathogen Phytophthora infestans. Whole transcriptome sequencing revealed expression of 86% of genes, with detectable differential expression of suites of genes under abiotic stress and in the presence of a host. The predicted proteome includes a large repertoire of proteins involved in plant pathogen interactions, although, surprisingly, the P. ultimum genome does not encode any classical RXLR effectors and relatively few Crinkler genes in comparison to related phytopathogenic oomycetes. A lower number of enzymes involved in carbohydrate metabolism were present compared to Phytophthora species, with the notable absence of cutinases, suggesting a significant difference in virulence mechanisms between P. ultimum and more host-specific oomycete species. Although we observed a high degree of orthology with Phytophthora genomes, there were novel features of the P. ultimum proteome, including an expansion of genes involved in proteolysis and genes unique to Pythium. We identified a small gene family of cadherins, proteins involved in cell adhesion, the first report of these in a genome outside the metazoans. CONCLUSIONS: Access to the P. ultimum genome has revealed not only core pathogenic mechanisms within the oomycetes but also lineage-specific genes associated with the alternative virulence and lifestyles found within the pythiaceous lineages compared to the Peronosporaceae.

Idiopathic superficial thrombophlebitis and the incidence of cancer in primary care patients.

PURPOSE: The association of spontaneous venous thromboembolism with occult malignancy is well established. Less clear is the incidence of subsequent cancer in patients with superficial thrombophlebitis. We wanted to determine the incidence of cancer after an episode of spontaneous superficial thrombophlebitis in a large general practice population. METHODS: The objective of this study was to assess the incidence of newly diagnosed malignancies in patients within 2 years after the diagnosis of a spontaneous episode of superficial thrombophlebitis and to compare this incidence with nonexposed matched control patients and the Dutch population. The patients and their controls were identified by a search in the electronic patient records of 5 primary health care centers in Amsterdam, the Netherlands. A standardized morbidity ratio was calculated using data of the Dutch cancer registry. RESULTS: A total number of 277 patients with superficial thrombophlebitis were identified, of which 250 patients had no cancer at study entry. In 5 of these 250 patients (2%; 95% confidence interval [CI], 1%-5%), a new malignancy was diagnosed within 2 years after their superficial thrombophlebitis compared with 2% (95% CI, 1%-4%) in the control group. The standardized morbidity ratio was 1.1 (95% CI, 0.5-2.7). A recurrent episode of superficial thrombophlebitis was observed in 18 of the 250 patients, and in 1 patient cancer was diagnosed within 24 months after the first episode of superficial thrombophlebitis. CONCLUSION: We conclude that a single episode of unprovoked superficial thrombophlebitis diagnosed by a family physician is not associated with an increased risk of subsequent cancer.

Predictability of persistent frequent attendance: a historic 3-year cohort study.

BACKGROUND: Few patients who attend GP consultations frequently continue to do so long term. While transient frequent attendance may be readily explicable, persistent frequent attendance often is not. It increases GPs' workload while reducing work satisfaction. It is neither reasonable, nor efficient to target diagnostic assessment and intervention at transient frequent attenders. AIM: To develop a prediction rule for selecting persistent frequent attenders, using readily available information from GPs' electronic medical records. DESIGN OF STUDY: A historic 3-year cohort study. METHOD: Data of 28 860 adult patients from 2003 to 2005 were examined. Frequent attenders were patients whose attendance rate ranked in the (age- and sex-adjusted) top 10% during 1 year (1-year frequent attenders) or 3 years (persistent frequent attenders). Bootstrapped multivariable logistic regression analysis was used to determine which predictors contained information on persistent frequent attendance. RESULTS: Of 3045 1-year frequent attenders, 470 (15.4%) became persistent frequent attenders. The prediction rule could update this prior probability to 3.3% (lowest value) or 43.3% (highest value). However, the 10th and 90th centiles of the posterior probability distribution were 7.4% and 26.3% respectively, indicating that the model performs modestly. The area under the receiver operating characteristic curve was 0.67 (95% confidence limits 0.64 and 0.69). CONCLUSION: Among 1-year frequent attenders, six out of seven are transient frequent attenders. With the present indicators, the rule developed performs modestly in selecting those more likely to become persistent frequent attenders.