How is atrial fibrillation detected in everyday healthcare? Results of a Dutch cohort study

BACKGROUND

Atrial fibrillation (AF) is a common arrhythmia with serious potential consequences when left untreated. For timely treatment, early detection is imperative. We explored how new AF is detected in patients aged ≥ 65 years in Dutch healthcare.

METHODS

The study cohort consisted of 9526 patients from 49 Dutch general practices in the usual-care arm of the Detecting and Diagnosing Atrial Fibrillation study. We automatically extracted data from the electronic medical records and reviewed individual records of patients who developed AF. Patient selection started in 2015, and data collection ended in 2019.

RESULTS

We included 258 patients with newly diagnosed AF. In 55.0% of the patients, the irregular heartbeat was first observed in general practice and in 16.3% in the cardiology department. Cardiologists diagnosed most cases (47.3%), followed by general practitioners (GPs; 33.7%). AF detection was triggered by symptoms in 64.7% of the patients and by previous stroke in 3.5%. Overall, patients aged 65-74 years more often presented with symptoms than those aged ≥ 75 years (73.5% vs 60.6%; p = 0.042). In 31.5% of the patients, AF was diagnosed incidentally ('silent AF'). Silent-AF patients were on average 2 years older than symptomatic-AF patients. GPs less often diagnosed silent AF than symptomatic AF (21.0% vs 39.0%; p = 0.008), whereas physicians other than GPs or cardiologists more often diagnosed symptomatic AF than silent AF (34.6% vs 11.9%; p < 0.001). Most diagnoses were based on a 12-lead electrocardiogram (93.8%).

CONCLUSION

Diagnosing AF is a multidisciplinary process. The irregular heartbeat was most often detected by the GP, but cardiologists diagnosed most cases. One-third of all newly diagnosed AF was silent.

How do Dutch general practitioners detect and diagnose atrial fibrillation? Results of an online case vignette study

Background

Detection and treatment of atrial fibrillation (AF) are important given the serious health consequences. AF may be silent or paroxysmal and remain undetected. It is unclear whether general practitioners (GPs) have appropriate equipment and optimally utilise it to detect AF. This case vignette study aimed to describe current practice and to explore possible improvements to optimise AF detection.

Methods

Between June and July 2017, we performed an online case vignette study among Dutch GPs. We aimed at obtaining at least 75 responses to the questionnaire. We collected demographics and asked GPs’ opinion on their knowledge and experience in diagnosing AF. GPs could indicate which diagnostic tools they have for AF. In six case vignettes with varying symptom frequency and physical signs, they could make diagnostic choices. The last questions covered screening and actions after diagnosing AF. We compared the answers to the Dutch guideline for GPs on AF.

Results

Seventy-six GPs completed the questionnaire. Seventy-four GPs (97%) thought they have enough knowledge and 72 (95%) enough experience to diagnose AF. Seventy-four GPs (97%) could order or perform ECGs without the interference of a cardiologist. In case of frequent symptoms of AF, 36–40% would choose short-term (i.e. 24–48 h) and 11–19% long-term (i.e. 7 days, 14 days or 1 month) monitoring. In case of non-frequent symptoms, 29–31% would choose short-term and 21–30% long-term monitoring. If opportunistic screening in primary care proves to be effective, 83% (58/70) will support it.

Conclusions

Responding GPs report to have adequate equipment, knowledge, and experience to detect and diagnose AF. Almost all participants can order ECGs. Reported monitoring duration was shorter than recommended by the guideline. AF detection could improve by increasing the monitoring duration.

Role of the Electronic Patient Record in the Development of General Practice in the Netherlands

From the end of the seventies practice computer systems have been introduced in Dutch general practice. In 1998 90% of the GPs had a practice computer and 60% used it for medical purposes, with good patient acceptance. Collaboration between pioneer GPs, professional organizations, academic institutions and software manufacturers has been of decisive importance. While the practice computer is early recognized as a powerful tool for administrative purposes, it is increasingly supporting clinical and preventive care, quality of care improvement, clinical training of students and vocational training of general practice trainees. Also for scientific research and practice supporting research, automatization has proven to be innovating. Much attention is paid to designing valid databases and database-related research. In addition, practice automatization has opened new perspectives for health policy and management. Further development of technical and methodological issues is needed, and, very importantly, of patients‘ and consumers’ involvement. EPR technology in general practice does not optimally work without good numerator and denominator data, and a good quality patient-doctor relationship over time. While the EPR is a useful tool to facilitate a better performance, it may enable the doctor to focus more on the health care essentials.

Multidisciplinary rehabilitation treatment versus cognitive behavioural therapy for patients with chronic fatigue syndrome: a randomized controlled trial

OBJECTIVES

The aim of this trial was to evaluate the difference in treatment effect, at 26 and 52 weeks after the start of treatment, between cognitive behavioural therapy (CBT) and multidisciplinary rehabilitation treatment (MRT) for patients with chronic fatigue syndrome (CFS).

DESIGN

Multicentre, randomized controlled trial of patients with CFS. Participants were randomly assigned to MRT or CBT.

SETTING

Four rehabilitation centres in the Netherlands.

SUBJECTS

A total of 122 patients participated in the trial.

MAIN OUTCOME MEASURES

Primary outcomes were fatigue measured by the fatigue subscale of the Checklist Individual Strength and health-related quality of life measured by the Short-Form 36. Outcomes were assessed prior to treatment and at 26 and 52 weeks after treatment initiation.

RESULTS

A total of 114 participants completed the assessment at 26 weeks, and 112 completed the assessment at 52 weeks. MRT was significantly more effective than CBT in reducing fatigue at 52 weeks. The estimated difference in fatigue between the two treatments was -3.02 [95% confidence interval (CI) -8.07 to 2.03; P = 0.24] at 26 weeks and -5.69 (95% CI -10.62 to -0.76; P = 0.02) at 52 weeks. Patients showed an improvement in quality of life over time, but between-group differences were not significant.

CONCLUSION

This study provides evidence that MRT is more effective in reducing long-term fatigue severity than CBT in patients with CFS. Although implementation in comparable populations can be recommended based on clinical effectiveness, it is advisable to analyse the cost-effectiveness and replicate these findings in another multicentre trial.

Towards a 'patient-centred' operationalisation of the new dynamic concept of health: a mixed methods study

OBJECTIVE

To evaluate among stakeholders the support for the new, dynamic concept of health, as published in 2011: 'Health as the ability to adapt and to self-manage', and to elaborate perceived indicators of health in order to make the concept measurable.

DESIGN

A mixed methods study: a qualitative first step with interviews and focus groups, followed by a quantitative survey.

PARTICIPANTS

Representatives of seven healthcare stakeholder domains, for example, healthcare providers, patients with a chronic condition and policymakers. The qualitative study involved 140 stakeholders; the survey 1938 participants.

RESULTS

The new concept was appreciated, as it addresses people as more than their illness and focuses on strengths rather than weaknesses. Caution is needed as the concept requires substantial personal input of which not everyone is capable. The qualitative study identified 556 health indicators, categorised into six dimensions: bodily functions, mental functions and perception, spiritual/existential dimension, quality of life, social and societal participation, and daily functioning, with 32 underlying aspects. The quantitative study showed all stakeholder groups considering bodily functions to represent health, whereas for other dimensions there were significant differences between groups. Patients considered all six dimensions almost equally important, thus preferring a broad concept of health, whereas physicians assessed health more narrowly and biomedically. In the qualitative study, 78% of respondents considered their health indicators to represent the concept.

CONCLUSIONS

To prevent confusion with health as 'absence of disease', we propose the use of the term 'positive health' for the broad perception of health with six dimensions, as preferred by patients. This broad perception deserves attention by healthcare providers as it may support shared decision-making in medical practice. For policymakers, the broad perception of 'positive health' is valuable as it bridges the gap between healthcare and the social domain, and by that it may demedicalise societal problems.

[What do older patients on polypharmacy know about their prescribed drugs?]

OBJECTIVE

To identify factors associated with appropriate knowledge about the indications for drugs prescribed to older patients on polypharmacy.

DESIGN

Cross-sectional study.

METHOD

In a primary care setting, patients aged 60 years and over who were taking five or more prescribed drugs simultaneously were asked about their medication by conducting home interviews and postal questionnaires. Multiple logistic regression analysis was used to evaluate the association between medication knowledge and explanatory variables such as medication use, sex, age, residential status and educational level.

RESULTS

Seven hundred and fifty-four participants, mean age 73.2 years, reported an average daily intake of nine (SD 3.0) prescribed drugs. Only 15% of the patients were able to recall the indication for each of their prescribed drugs. Variables that were negatively associated with correct reporting of all indications were: taking many prescribed drugs (≥ 10 vs. ≤ 5 drugs: odds ratio (OR) 0.05), age 80 years or over (vs. 60-69 years: OR 0.47) and male sex (vs. females: OR 0.53). Patients living with a partner were more knowledgeable than patients living alone (OR 2.11). We did not find an association with educational level.

CONCLUSION

Among older patients using five or more prescribed drugs, there was little understanding of the indications for their drugs, especially among patients taking the highest number of drugs, patients aged 80 years or over, and men. Patients living independently with a partner were more knowledgeable than others.

Exploring the process when developing a lifestyle intervention in primary care for type 2 diabetes: a longitudinal process evaluation

OBJECTIVES

A thorough understanding of the processes involved in lifestyle interventions is needed in order to close the gap between research and daily practice. This study explored the processes involved in the provision of a lifestyle intervention to patients with type 2 diabetes mellitus (T2DM) by health care professionals in primary care.

STUDY DESIGN

Mixed methods.

METHODS

Health care professionals were asked to intensify lifestyle interventions for patients with T2DM in a routine care setting. Data were collected by serial interviews with health care professionals and patients, recorded consultations, an activity questionnaire and biomedical information. Qualitative data were analysed using a framework analysis with a phenomenological approach.

RESULTS

The lifestyle intervention developed by the health care professionals included motivational interviewing, a nutrition and physical activity diary, and a multidisciplinary approach [physiotherapist, dietician, general practitioner and diabetes practice nurse (DPN)]. Participants and health care professionals were positive about the intervention, and patients were more active (P = 0.027), lost weight (P = 0.031) and had lower levels of glycated haemoglobin (P = 0.012). However, qualitative data showed that patients were passive during the consultation, and did not ask questions about ways to improve their lifestyle. DPNs did not use motivational interviewing optimally; provided patients with information that was difficult to understand; and were easily satisfied with the efforts of the patients.

CONCLUSIONS

Lifestyle intervention for patients with T2DM is difficult in routine primary care. DPNs should adapt to the knowledge level of the patients, and patients must be stimulated to take an active role in their treatment. Patients and health care professionals should become equal partners in determining mutually agreeable treatment plans and goals.

Development and validation of an ankle brachial index risk model for the prediction of cardiovascular events

BACKGROUND

The ankle brachial index (ABI) is related to risk of cardiovascular events independent of the Framingham risk score (FRS). The aim of this study was to develop and evaluate a risk model for cardiovascular events incorporating the ABI and FRS.

DESIGN

An analysis of participant data from 18 cohorts in which 24,375 men and 20,377 women free of coronary heart disease had ABI measured and were followed up for events.

METHODS

Subjects were divided into a development and internal validation dataset and an external validation dataset. Two models, comprising FRS and FRS + ABI, were fitted for the primary outcome of major coronary events.

RESULTS

In predicting events in the external validation dataset, C-index for the FRS was 0.672 (95% CI 0.599 to 0.737) in men and 0.578 (95% CI 0.492 to 0.661) in women. The FRS + ABI led to a small increase in C-index in men to 0.685 (95% CI 0.612 to 0.749) and large increase in women to 0.690 (95% CI 0.605 to 0.764) with net reclassification improvement (NRI) of 4.3% (95% CI 0.0 to 7.6%, p = 0.050) and 9.6% (95% CI 6.1 to 16.4%, p < 0.001), respectively. Restricting the FRS + ABI model to those with FRS intermediate 10-year risk of 10 to 19% resulted in higher NRI of 15.9% (95% CI 6.1 to 20.6%, p < 0.001) in men and 23.3% (95% CI 13.8 to 62.5%, p = 0.002) in women. However, incorporating ABI in an improved newly fitted risk factor model had a nonsignificant effect: NRI 2.0% (95% CI 2.3 to 4.2%, p = 0.567) in men and 1.1% (95% CI 1.9 to 4.0%, p = 0.483) in women.

CONCLUSIONS

An ABI risk model may improve prediction especially in individuals at intermediate risk and when performance of the base risk factor model is modest.

[How much do patients and health professionals (really) know? The surplus value of a home visit to the patient with polypharmacy by the practice nurse, to support medication reviews in primary care]

BACKGROUND

Polypharmacy in older people should be addressed by an annual review of the chronic medication. In the PIL-study this was done by an integrated approach by GP, practice nurse, pharmacist, specialist and patient. All patients were first visited at home by the practice nurse.

RESEARCH QUESTIONS

What 'over the counter' (OTC) medications do polypharmacy patients use? Do they know the indications of the prescribed medication? Does medication use according to the patient match with medication use according to the records of GP and pharmacist?

METHOD

Inclusion criteria were: age 60 years or older, daily use of five or more chronic medications, mental competence, and adequate command of the Dutch language. All patients were visited at home by the practice nurse, who made an inventory of the actual drug use.

RESULTS

Five hundred fifty patients used a total of 5576 drugs, including 527 (9.4%) OTC medication. Patients knew the indication of 64% of the prescribed medication. The number of prescribed drugs that a patient actually used did not match the numbers known to GP and pharmacist. In 60.4% of all medication prescriptions there was complete agreement between GP, pharmacist and patient. On a patient level agreement was 18.7%.

CONCLUSIONS

Home visits by the nurse practitioner to make an inventory of the medication as reported by the patient seem to have an added value.

Patient adherence to prescribed medication instructions for dyspepsia: the DIAMOND-study

BACKGROUND

Insight into patient adherence is needed to enable an effect evaluation of medication for dyspepsia.

OBJECTIVES

Adherence was explored by investigating two adherence outcome measures (completeness and intake fidelity) using data from the DIAMOND-study.

METHODS

The DIAMOND-study is a pragmatic RCT comparing a 'step-up' with a 'step-down' treatment strategy. In step 1 participants (n =653) were instructed to use five pills/day for maximally 30 days: an antacid 4dd plus a placebo 1dd ('step-up') or a proton pump inhibitor 1dd plus a placebo 4dd ('step-down'). If the complaints persisted, step 2 was started (H(2)-receptor antagonist 2dd), and subsequently step 3 (five pills/day, placebo and verum vice versa from step 1). Completeness was assessed by pill counts, intake fidelity by patient questionnaires measuring the degree to which patients adhered to specific instructions concerning timing, frequency, dose and way of intake.

RESULTS

In step 1, patients used on average 3.9 pills/day (78% of the prescribed doses), in step 2, 1.7 pills/day (85%) and in step 3, 3.6 pills/day (72%). For the four times daily pills, half of the patients used less than 80% of the prescribed pills per day. This was one third of the patients for the twice daily pills and one quarter for the once daily pills. There were no completeness differences between active or placebo medication and no differences between the study arms. As regards intake fidelity, 70% of the patients made one or more errors in the medication intake.

CONCLUSION

There is room for improvement in adherence rates for dyspepsia medication.

Which patient-related factors determine self-perceived patient adherence to prescribed dyspepsia medication?

Patient adherence to medical treatment for dyspepsia is disappointing, whereas adherence is crucial for a proper evaluation of treatment. This prospective study used elements of the Integrated Change Model and Weiner's Attribution Theory to describe patients' important cognitions and their interrelationships regarding self-perceived adherence to short-term medical treatment for dyspepsia. Patient questionnaires measured the predictors before treatment and self-perceived adherence after treatment. Approximately one-quarter of the patients indicated that they were non-adherent (n = 347). Univariate and multiple linear regression analyses revealed several significant predictors that explained 44% of the variance in self-perceived adherence. Patients with a low educational level, patients who claimed to regularly forget their medication in general, patients with a low self-efficacy or a low intention were less likely to be adherent. These results may indicate targets for interventions designed to improve adherence to medical treatment for dyspepsia. For instance, asking about expected difficulties in taking acid suppressants (e.g. forgetfulness or medication use at weekends) and making action plans to overcome these difficulties (e.g. using reminders) may result in improved adherence rates. Such an approach may reach a substantial number of patients since one in five patients in our study experienced some difficulties in taking medication.

Soluble or insoluble fibre in irritable bowel syndrome in primary care? Randomised placebo controlled trial

OBJECTIVE

To determine the effectiveness of increasing the dietary content of soluble fibre (psyllium) or insoluble fibre (bran) in patients with irritable bowel syndrome.

DESIGN

Randomised controlled trial.

SETTING

General practice.

PARTICIPANTS

275 patients aged 18-65 years with irritable bowel syndrome.

INTERVENTIONS

12 weeks of treatment with 10 g psyllium (n=85), 10 g bran (n=97), or 10 g placebo (rice flour) (n=93).

MAIN OUTCOME MEASURES

The primary end point was adequate symptom relief during at least two weeks in the previous month, analysed after one, two, and three months of treatment to assess both short term and sustained effectiveness. Secondary end points included irritable bowel syndrome symptom severity score, severity of abdominal pain, and irritable bowel syndrome quality of life scale.

RESULTS

The proportion of responders was significantly greater in the psyllium group than in the placebo group during the first month (57% v 35%; relative risk 1.60, 95% confidence interval 1.13 to 2.26) and the second month of treatment (59% v 41%; 1.44, 1.02 to 2.06). Bran was more effective than placebo during the third month of treatment only (57% v 32%; 1.70, 1.12 to 2.57), but this was not statistically significant in the worst case analysis (1.45, 0.97 to 2.16). After three months of treatment, symptom severity in the psyllium group was reduced by 90 points, compared with 49 points in the placebo group (P=0.03) and 58 points in the bran group (P=0.61 versus placebo). No differences were found with respect to quality of life. Fifty four (64%) of the patients allocated to psyllium, 54 (56%) in the bran group, and 56 (60%) in the placebo group completed the three month treatment period. Early dropout was most common in the bran group; the main reason was that the symptoms of irritable bowel syndrome worsened.

CONCLUSIONS

Psyllium offers benefits in patients with irritable bowel syndrome in primary care.

TRIAL REGISTRATION

Clinical trials NCT00189033.

Soluble or insoluble fibre in irritable bowel syndrome in primary care? Randomised placebo controlled trial

OBJECTIVE

To determine the effectiveness of increasing the dietary content of soluble fibre (psyllium) or insoluble fibre (bran) in patients with irritable bowel syndrome.

DESIGN

Randomised controlled trial.

SETTING

General practice.

PARTICIPANTS

275 patients aged 18-65 years with irritable bowel syndrome.

INTERVENTIONS

12 weeks of treatment with 10 g psyllium (n=85), 10 g bran (n=97), or 10 g placebo (rice flour) (n=93).

MAIN OUTCOME MEASURES

The primary end point was adequate symptom relief during at least two weeks in the previous month, analysed after one, two, and three months of treatment to assess both short term and sustained effectiveness. Secondary end points included irritable bowel syndrome symptom severity score, severity of abdominal pain, and irritable bowel syndrome quality of life scale.

RESULTS

The proportion of responders was significantly greater in the psyllium group than in the placebo group during the first month (57% v 35%; relative risk 1.60, 95% confidence interval 1.13 to 2.26) and the second month of treatment (59% v 41%; 1.44, 1.02 to 2.06). Bran was more effective than placebo during the third month of treatment only (57% v 32%; 1.70, 1.12 to 2.57), but this was not statistically significant in the worst case analysis (1.45, 0.97 to 2.16). After three months of treatment, symptom severity in the psyllium group was reduced by 90 points, compared with 49 points in the placebo group (P=0.03) and 58 points in the bran group (P=0.61 versus placebo). No differences were found with respect to quality of life. Fifty four (64%) of the patients allocated to psyllium, 54 (56%) in the bran group, and 56 (60%) in the placebo group completed the three month treatment period. Early dropout was most common in the bran group; the main reason was that the symptoms of irritable bowel syndrome worsened.

CONCLUSIONS

Psyllium offers benefits in patients with irritable bowel syndrome in primary care.

TRIAL REGISTRATION

Clinical trials NCT00189033.

Influence of gastric mucosal status on success of stepwise acid suppressive therapy for dyspepsia

BACKGROUND

The most effective initial treatment strategy of dyspepsia is still under debate. Individual biological characteristics, such as condition of gastric mucosa, might contribute to selection of the most appropriate acid suppression treatment strategy.

AIM

To assess whether pre-treatment testing of gastric mucosal status is relevant for treatment success in an RCT comparing step-up and step-down therapies in newly diagnosed dyspepsia patients.

METHODS

Baseline serum samples were collected to assess gastric mucosal status using serum levels of pepsinogens-I&II, gastrin-17, and Helicobacter pylori IgA/IgG-antibodies. The 6-month treatment success was compared between step-up and step-down for patients with serum diagnoses: normal; gastritis; corpus atrophy or antrum atrophy.

RESULTS

In all, 519 patients (M/F: 249/270, age: 47 (18-85) years, 29%H. pylori+) were randomized to step-up (n = 293) or step-down (n = 226). Normal mucosa, gastritis and corpus atrophy were diagnosed serologically in 70%, 28% and 2% of the patients, evenly distributed between the strategies (P = 0.65). Treatment success was achieved in respectively, 69%, 70% and 70% for the serum diagnosis groups, and did not differ between the strategies.

CONCLUSIONS

Dyspepsia treatment success could not be predicted by gastric mucosal status. Therefore, serum diagnosis of gastric mucosal status is no useful tool for patient allocation to acid suppressive treatment strategies.

Psychopathology is associated with dyspeptic symptom severity in primary care patients with a new episode of dyspepsia

BACKGROUND

Personality and psychiatric disorders are reported to be more common in dyspeptic patients with severe complaints, but it remains unclear whether this association exists for patients with mild and moderate dyspepsia.

AIM

To study the association between dyspeptic symptom severity and psychopathology, major life events and coping ability in patients with a new episode of dyspepsia. METHODS; Dyspeptic symptom severity was measured using the validated eight symptom Veldhuyzen van Zanten questionnaire. Psychopathology was measured using the Symptom Check List-90 (SCL 90). Major life events were measured with a modified version of the Social Readjustment Rating Scale (SRRS). Coping styles were measured by a short version of the Utrecht Coping Questionnaire, distinguishing six coping styles. Linear regression was used to assess the relationship between dyspepsia symptom severity and psychological factors.

RESULTS

In all, 664 patients with a new episode of uninvestigated dyspepsia, aged >18 years were included. Dyspeptic symptom severity was positively correlated with the presence of depression (P < 0.01), somatization symptoms (P < 0.01), use of an active coping style (P < 0.01) and negatively correlated with age (P < 0.01).

CONCLUSIONS

Primary care patients consulting with dyspepsia have higher levels of depression and somatization especially at younger age. An active coping style is associated with dyspepsia symptom severity.

[The Dr A.H. Heineken Prize for Medicine 2008 awarded to Sir Richard Peto]

The increasingly strong interaction between biomedical and epidemiological research is one of the most important steps forward in medicine and public health since World War II. Crucial breakthroughs were the development of powerful observational epidemiological studies, the introduction of convincingly designed clinical trials, and meta-analyses to objectively summarise the results of multiple studies. For this progress, the work of Sir Richard Peto (born in 1943), epidemiologist and statistician at the University of Oxford, Great Britain, has been essential. Peto combined innovative methodological contributions with large-scaled empirical studies, often based on worldwide collaborations, with a special focus on smoking and health, treatment of breast cancer, and cholesterol-lowering interventions. His work both produced and evoked an impressive evidence base to improve clinical and public health practice. In accordance with the advice of a selection committee of the Royal Netherlands Academy of Arts and Sciences, he was awarded the Dr A.H. Heineken Prize for Medicine on 2 October 2008.

Randomized patients in IBS research had different disease characteristics compared to eligible and recruited patients

OBJECTIVE

The recruitment process may generate a selected patient sample, which may threaten the generalizability of trial results. This risk is particularly high in case disease and patient characteristics demonstrate a wide variation, such as in irritable bowel syndrome (IBS). We compared IBS patients who were selected, approached, and randomized to participate in a clinical trial assessing the efficacy of dietary fiber therapy in IBS.

STUDY DESIGN AND SETTING

Retrospective survey in primary care patients diagnosed with IBS by their general practitioner in the past 2 years selected and invited for participation in a trial. Characteristics were compared between randomized patients (n=193) nonrandomized eligible patients (n=371), and patients not eligible for participating in the trial (n=724).

RESULTS

Of the 2,100 IBS patients, 1,288 (61%) returned the questionnaire. Randomized patients had a higher intensity of IBS abdominal pain as compared to the other groups, a higher consultation rate and a longer IBS disease history. Noneligible patients had less active IBS symptoms.

CONCLUSIONS

Patients randomized do differ from those nonrandomized in IBS disease characteristics. These observations may have implications for the applicability of our research outcome.

Ankle brachial index combined with Framingham Risk Score to predict cardiovascular events and mortality: a meta-analysis

CONTEXT

Prediction models to identify healthy individuals at high risk of cardiovascular disease have limited accuracy. A low ankle brachial index (ABI) is an indicator of atherosclerosis and has the potential to improve prediction.

OBJECTIVE

To determine if the ABI provides information on the risk of cardiovascular events and mortality independently of the Framingham risk score (FRS) and can improve risk prediction.

DATA SOURCES

Relevant studies were identified. A search of MEDLINE (1950 to February 2008) and EMBASE (1980 to February 2008) was conducted using common text words for the term ankle brachial index combined with text words and Medical Subject Headings to capture prospective cohort designs. Review of reference lists and conference proceedings, and correspondence with experts was conducted to identify additional published and unpublished studies.

STUDY SELECTION

Studies were included if participants were derived from a general population, ABI was measured at baseline, and individuals were followed up to detect total and cardiovascular mortality.

DATA EXTRACTION

Prespecified data on individuals in each selected study were extracted into a combined data set and an individual participant data meta-analysis was conducted on individuals who had no previous history of coronary heart disease.

RESULTS

Sixteen population cohort studies fulfilling the inclusion criteria were included. During 480,325 person-years of follow-up of 24,955 men and 23,339 women, the risk of death by ABI had a reverse J-shaped distribution with a normal (low risk) ABI of 1.11 to 1.40. The 10-year cardiovascular mortality in men with a low ABI (< or = 0.90) was 18.7% (95% confidence interval [CI], 13.3%-24.1%) and with normal ABI (1.11-1.40) was 4.4% (95% CI, 3.2%-5.7%) (hazard ratio [HR], 4.2; 95% CI, 3.3-5.4). Corresponding mortalities in women were 12.6% (95% CI, 6.2%-19.0%) and 4.1% (95% CI, 2.2%-6.1%) (HR, 3.5; 95% CI, 2.4-5.1). The HRs remained elevated after adjusting for FRS (2.9 [95% CI, 2.3-3.7] for men vs 3.0 [95% CI, 2.0-4.4] for women). A low ABI (< or = 0.90) was associated with approximately twice the 10-year total mortality, cardiovascular mortality, and major coronary event rate compared with the overall rate in each FRS category. Inclusion of the ABI in cardiovascular risk stratification using the FRS would result in reclassification of the risk category and modification of treatment recommendations in approximately 19% of men and 36% of women.

CONCLUSION

Measurement of the ABI may improve the accuracy of cardiovascular risk prediction beyond the FRS.