Marie-Louise Bartelink

High dietary menaquinone intake is associated with reduced coronary calcification

BACKGROUND Dietary vitamin K is thought to decrease risk of cardiovascular disease by reducing coronary calcification, but inconsistent results are reported. This may be due to different effects of vitamin K(1) (phylloquinone) and vitamin K(2) (menaquinone, MK), but few studies included both. METHODS We investigated the association of intake of phylloquinone and menaquinone, including its subtypes (MK4-MK10), with coronary calcification in a cross-sectional study among 564 post-menopausal women. Phylloquinone and menaquinone intake was estimated using a food-frequency questionnaire. RESULTS Sixty-two percent (n=360) of the women had coronary calcification based on 1.5-mm thick slices. Phylloquinone intake was not associated with coronary calcification with a relative risk (RR) of 1.17 (95%-confidence interval: 0.96-1.42; p(trend)=0.11) of the highest versus lowest quartile. Menaquinone intake was associated with decreased coronary calcification with an RR of 0.80 (95%-CI: 0.65-0.98; p(trend)=0.03). CONCLUSION This study shows that high dietary menaquinone intake, but probably not phylloquinone, is associated with reduced coronary calcification. Adequate menaquinone intakes could therefore be important to prevent cardiovascular disease.

A clinical prediction model for the presence of peripheral arterial disease — the benefit of screening individuals before initiation of measurement of the ankle—brachial index: an observational study

Measurement of the ankle—brachial index (ABI) can provide important information about the presence of subclinical atherosclerosis. Performing the ABI in the overall population is not feasible, but it can be used in a selected population. A simple prediction rule could be of much use to estimate the risk of an abnormal ABI. This was designed as an observational study in the setting of 955 general practices in The Netherlands. A total of 7454 patients aged ≥ 55 years presenting with at least one vascular risk factor (smoking, hypertension, diabetes, and hypercholesterolemia) and no complaints of intermittent claudication were included. Patients were selected by the general practitioner during visiting hours and from medical records. Main outcome measures included the prevalence of PAD, defined as an ABI below 0.9, which was related to vascular risk factors using regression analyses on which the PREVALENT clinical prediction model was developed. The overall prevalence of PAD was 18.4%. Since the treatment of individuals with a history of coronary heart disease and cerebrovascular disease will not be influenced by the finding of asymptomatic PAD, these individuals were not taken into account for the development of the clinical prediction model. Analyses showed a significantly increased risk for PAD with increasing age, smoking, and hypertension. The clinical prediction model giving risk factor points per factor (age: 1 point per 5 years starting at 55 years; ever smoked: 2 points; currently smoking: 7 points; and hypertension: 3 points), showed a proportional increase of the PAD prevalence with each increasing risk profile (range: 7.0—40.6%). In conclusion, based on the PREVALENT clinical prediction model, the general practitioner is able to identify a high-risk population in which measurement of ABI is useful.

High Blood Pressure in Pregnancy and Coronary Calcification

A considerable proportion of pregnant women develop high blood pressure in pregnancy. Although it is assumed that this condition subsides after pregnancy, many of these women develop the metabolic syndrome later in life and are at increased risk to develop coronary heart disease. Atherosclerosis development is considered in between risk factors and occurrence of vascular symptoms. We set out to cross-sectionally study the relation of high blood pressure during pregnancy with risk of coronary calcification. The study population was composed 491 healthy postmenopausal women selected from a population-based cohort study. Information on high blood pressure during pregnancy was obtained using a questionnaire. Between 2004 and 2005, the women underwent a multidetector computed tomography (Philips Mx 8000 IDT 16) to assess coronary calcium. The Agatston score, volume, and mass measurements were used to quantify coronary calcium. A total of 30.7% of the women reported to have had high blood pressure in pregnancy. Body mass index (odds ratio [OR]: 1.05; 95% CI: 1.01 to 1.09) and diastolic blood pressure (OR: 1.03; 95% CI: 1.01 to 1.05) were significantly related to a history of high blood pressure in pregnancy. Age was significantly related to increased coronary calcification. Women with a history of high blood pressure during pregnancy had a 57% increased risk of having coronary calcification compared with those women without this condition (OR: 1.57; 95% CI: 1.04 to 2.37). After adjusting for age, the relation did not change (OR: 1.64; 95% CI: 1.07 to 2.53). We concluded that high blood pressure during pregnancy is associated with an increased risk of coronary calcification later in life.

Ankle brachial index measurement in primary care: are we doing it right?

BACKGROUND The reference standard for diagnosing peripheral arterial disease in primary care is the ankle brachial index (ABI). Various methods to measure ankle and brachial blood pressures and to calculate the index are described. AIM To compare the ABI measurements performed in primary care with those performed in the vascular laboratory. Furthermore, an inventory was made of methods used to determine the ABI in primary care. DESIGN OF STUDY Cross-sectional study. SETTING Primary care practice and outpatient clinic. METHOD Consecutive patients suspected of peripheral arterial disease based on ABI assessment in primary care practices were included. The ABI measurements were repeated in the vascular laboratory. Referring GPs were interviewed about method of measurement and calculation of the index. From each patient the leg with the lower ABI was used for analysis. RESULTS Ninety-nine patients of 45 primary care practices with a mean ABI of 0.80 (standard deviation [SD] = 0.27) were included. The mean ABI as measured in the vascular laboratory was 0.82 (SD = 0.26). A Bland-Altman plot demonstrated great variability between ABI measurements in primary care practice and the vascular laboratory. Both method of blood pressure measurements and method of calculating the ABI differed greatly between primary care practices. CONCLUSION This study demonstrates that the ABI is often not correctly determined in primary care practice. This phenomenon seems to be due to inaccurate methods for both blood pressure measurements and calculation of the index. A guideline for determining the ABI with a hand-held Doppler, and a training programme seem necessary.

Reproductive factors, metabolic factors, and coronary artery calcification in older women.

Objective: Metabolic disturbances may explain the increased cardiovascular risk associated with reproductive factors. This cohort study investigated the relationship between reproductive factors and coronary artery calcification in elderly women and whether this relationship could be explained by metabolic disturbances. Design: In total, 568 postmenopausal women were included in this cross-sectional study. Information about the womens reproductive life was obtained by a questionnaire. Metabolic factors were measured during a single visit. Coronary artery calcification was assessed with a multislice computed tomography scanner and dichotomized as absent or present. Logistic regression analysis was used to assess the relationship between reproductive factors and coronary artery calcification. Crude and multivariate adjusted odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated. In addition, ORs were adjusted for several metabolic and cardiovascular risk factors. Results: The mean age was 66.9 (± 5.5) years. Women with a history of irregular menstrual cycle lengths, as opposed to women with a history of regular menstrual cycles (26-30 d), had an increased risk of coronary artery calcification; multivariate-adjusted OR = 2.73 (95%CI: 1.24-5.98). Four or more pregnancies, compared with never pregnant, yielded an multivariate-adjusted OR of 1.89 (95% CI: 1.00-3.58). Having four children or more, compared with having no children, yielded a multivariate-adjusted OR of 1.97 (95% CI: 1.00-3.89). Adjustment for metabolic factors and other cardiovascular risk factors did not fully explain theses relationships. Conclusion: Multigravidity (more than four pregnancies), multiparity (more than four births), and irregular menstrual cycle lengths were related to an increased risk of coronary artery disease. These associations could not be explained by metabolic abnormalities.

The ClaudicatioNet concept: design of a national integrated care network providing active and healthy aging for patients with intermittent claudication.

Introduction: Intermittent claudication (IC) is a manifestation of peripheral arterial occlusive disease (PAOD). Besides cardiovascular risk management, supervised exercise therapy (SET) should be offered to all patients with IC. Outdated guidelines, an insufficient number of specialized physiotherapists (PTs), lack of awareness of the importance of SET by referring physicians, and misguided financial incentives all seriously impede the availability of a structured SET program in The Netherlands. Description of care practice: By initiating regional care networks, ClaudicatioNet aims to improve the quality of care for patients with IC. Based on the chronic care model as a conceptual framework, these networks should enhance the access, continuity, and (cost) efficiency of the health care system. With the aid of a national database, health care professionals will be able to benchmark patient results while ClaudicatioNet will be able to monitor quality of care by way of functional and patient reported outcome measures. Discussion: The success of ClaudicatioNet is dependent on several factors. Vascular surgeons, general practitioners and coordinating central caregivers will need to team up and work in close collaboration with specialized PTs. A substantial task in the upcoming years will be to monitor the quality, volume, and distribution of ClaudicatioNet PTs. Finally, misguided financial incentives within the Dutch health care system need to be tackled. Conclusion: With ClaudicatioNet, integrated care pathways are likely to improve in the upcoming years. This should result in the achievement of optimal quality of care for all patients with IC.

Applicability of the ankle-brachial-index measurement as screening device for high cardiovascular risk: an observational study

BackgroundScreening with ankle-brachial index (ABI) measurement could be clinically relevant to avoid cardiovascular events in subjects with asymptomatic atherosclerosis. To assess the practical impact of guidelines regarding the use of ABI as a screening tool in general practice, the corresponding number needed to screen, including the required time investment, and the feasibility of ABI performance, was assessed.MethodsAn observational study was performed in the setting of 955 general practices in the Netherlands. Overall, 13,038 subjects of ≥55 years presenting with symptoms of intermittent claudication and/or presenting with ≥ one vascular risk factor were included. Several guidelines recommend the ABI as an additional measurement in selected populations for risk assessment for cardiovascular morbidity.ResultsScreening of the overall population of ≥50 years results in ≈862 subjects per general practice who should be screened, resulting in a time-requirement of approximately 6 weeks of full time work. Using an existing clinical prediction model, 247 patients per general practice should be screened for PAD by ABI measurement.ConclusionScreening the entire population of ≥50 years will in our opinion not be feasible in general practice. A more rationale and efficient approach might be screening of subsets of the population of ≥55 years based on a clinical prediction model.

General practice trainees' information searching strategies for clinical queries encountered in daily practice

BACKGROUND Earlier studies have shown that clinical queries are common among doctors. Data on the information-seeking behaviour of general practice (GP) trainees are scarce though, and numbers studied are small. OBJECTIVE The objective of this study was to determine how often and how GP trainees search for answers to clinical queries encountered in daily clinical practice. METHODS Third-year GP trainees kept logs on all patient contacts for eight consecutive practice days. Information was obtained on patient contacts (description), clinical queries (frequency, type), seeking behaviour (frequency, moment, reason not to search, resources used, duration of search) and answers (frequency, impact). Descriptive analyses were performed; frequencies and percentages were computed. We calculated the number of clinical queries per patient, the number of searches per query and the number of answers per search. RESULTS Seventy-six trainees reported 1533 clinical queries about 7300 patients presenting 7619 complaints [mean of 0.2 queries per patient, standard deviation (SD) 0.1]. For most of the queries trainees pursued an answer (mean of 0.8 per query, SD 0.2), mostly during consultation (61% of searches), and frequently retrieved answers (mean of 0.8 per search, SD 0.17) they reported to improve clinical decision making in 26%. Most common resources were colleagues or supervisors (28%), and national GP guidelines (26%). The median duration of a search was 4 minutes (interquartile range 3). CONCLUSION GP trainees have one clinical query per five patients. They often attempted to find answers and reported to succeed in most of the searches, primarily by consulting supervisors or colleagues and national GP guidelines.

Elevated blood pressure and electrocardiographic frontal T axis and spatial QRS-T angle changes in postmenopausal women

INTRODUCTION Frontal T axis and spatial QRS-T angle are both measures of disturbances in ventricular repolarization and depolarization. We determined whether increased blood pressure is a risk factor for changes in these parameters in postmenopausal women free of left ventricular hypertrophy. MATERIALS AND METHODS This cross-sectional study included 969 women. A standard 12-lead electrocardiogram (ECG) was recorded, and frontal T axes and spatial QRS-T angles were computed from vectorcardiography. Logistic regression analysis was used to assess the relationship between systolic and diastolic blood pressures on the one hand and both ECG parameters on the other. RESULTS Odds ratios were 1.08 (95% confidence interval [CI], 0.99-1.18) and 1.12 (95% CI, 1.03-1.23) per 10 mm Hg systolic blood pressure for frontal T axis and QRS-T angle, respectively. These values were 1.05 (95% CI, 0.95-1.16) and 1.12 (95% CI, 1.02-1.23) per 5 mm Hg diastolic blood pressure for frontal T-axis and QRS-T angle, respectively. CONCLUSION Elevated blood pressure may lead to ventricular depolarization and repolarization disturbances before overt ECG left ventricular hypertrophy has developed.

Development and validation of a new instrument measuring guideline adherence in clinical practice

BACKGROUND Education in evidence-based medicine (EBM) is an important part of the postgraduate training of GPs. Evaluation of its effect on EBM behaviour in daily clinical practice is difficult and instruments are scarce. Working in accordance with guidelines is considered as one of the key indicators of EBM behaviour. OBJECTIVE To develop and validate an instrument assessing guideline adherence of GP trainees in clinical practice. METHODS We developed an instrument that assesses guideline adherence, taking conscious deviation into account. The instrument assesses guideline adherence on 59 different management decisions (diagnosis N = 17, therapy N = 20, referral N = 22) for 23 conditions as described in 27 different clinical practice guidelines. We validated this instrument using performance data as collected by third-year GP trainees on three important properties: validity, reliability and feasibility. RESULTS Performance data were collected by 76 GP trainees on 12106 patient consultations with 12587 different reasons for encounter. Overall, guideline adherence was 82% (95% confidence interval 77-88%). The significant correlation with the national GP knowledge test (r 0.33, P 0.004) showed the instrument to be a valid instrument. Interrater reliabilities (intraclass correlation coefficient) varied between moderate and excellent (0.64-1.00, P < 0.001). The instrument proved feasible with coverage of 24% (N = 3082) of reasons for encounter presented to GP trainees and a mean and median time of 1 minute to score a patient consultation. CONCLUSION This instrument proved valid, reliable and feasible to assess guideline adherence among trainees in the clinical primary care setting.