Jeremy van Vlymen

Creatinine fluctuation has a greater effect than the formula to estimate glomerular filtration rate on the prevalence of chronic kidney disease.

Background/Aims: Cases of chronic kidney disease (CKD) are defined by the estimated glomerular filtration rate (eGFR), calculated using the Modified Diet in Renal Disease (MDRD) or, more recently, the CKD Epidemiology Collaboration (CKD-EPI) formula. This study set out to promote a systematic approach to reporting CKD prevalence. Design, Setting, Participants and Measurements: The study explores the impact of the way in which eGFR is calculated on the prevalence of CKD. We took into account whether including (1) ethnicity, (2) using a single eGFR, (3) using more than 1 eGFR value or (4) using the CKD-EPI formula affected the estimates of prevalence. Sample: Of 930,997 registered patients, 36% (332,891) have their eGFR defined (63% of those aged 50–74 years, 81% >75 years). Results: The prevalence of stage 3–5 CKD is 5.41% (n = 50,331). (1) Not including ethnicity data the prevalence would be 5.49%, (2) just using the latest eGFR 6.4%, (3) excluding intermediary values 5.55% and (4) using the CKD-EPI equation 4.8%. All changes in eGFR (t test) and the proportion with CKD (χ2 test) were significant (p < 0.001). Using serum-creatinine-calculated eGFR instead of laboratory data reduced the prevalence of stage 3–5 CKD by around 0.01%. Sixty-six percent of people with stage 3–5 disease have cardiovascular disease and 4.0% significant proteinuria using the MDRD formula; the corresponding figures using CKD-EPI are 74 and 4.6%. Conclusions: A standardised approach to reporting case finding would allow a better comparison of prevalence estimates. Using a single eGFR tends to inflate the reported prevalence of CKD by ignoring creatinine fluctuation; this effect is greater than the difference between MDRD and CKD-EPI.

The QICKD study protocol: a cluster randomised trial to compare quality improvement interventions to lower systolic BP in chronic kidney disease (CKD) in primary care

BackgroundChronic kidney disease (CKD) is a relatively newly recognised but common long-term condition affecting 5 to 10% of the population. Effective management of CKD, with emphasis on strict blood pressure (BP) control, reduces cardiovascular risk and slows the progression of CKD. There is currently an unprecedented rise in referral to specialist renal services, which are often located in tertiary centres, inconvenient for patients, and wasteful of resources. National and international CKD guidelines include quality targets for primary care. However, there have been no rigorous evaluations of strategies to implement these guidelines. This study aims to test whether quality improvement interventions improve primary care management of elevated BP in CKD, reduce cardiovascular risk, and slow renal disease progressionDesignCluster randomised controlled trial (CRT)MethodsThis three-armed CRT compares two well-established quality improvement interventions with usual practice. The two interventions comprise: provision of clinical practice guidelines with prompts and audit-based education.The study population will be all individuals with CKD from general practices in eight localities across England. Randomisation will take place at the level of the general practices. The intended sample (three arms of 25 practices) powers the study to detect a 3 mmHg difference in systolic BP between the different quality improvement interventions. An additional 10 practices per arm will receive a questionnaire to measure any change in confidence in managing CKD. Follow up will take place over two years. Outcomes will be measured using anonymised routinely collected data extracted from practice computer systems. Our primary outcome measure will be reduction of systolic BP in people with CKD and hypertension at two years. Secondary outcomes will include biomedical outcomes and markers of quality, including practitioner confidence in managing CKD.A small group of practices (n = 4) will take part in an in-depth process evaluation. We will use time series data to examine the natural history of CKD in the community. Finally, we will conduct an economic evaluation based on a comparison of the cost effectiveness of each intervention.Clinical Trials RegistrationISRCTN56023731. ClinicalTrials.gov identifier.

Audit-based education lowers systolic blood pressure in chronic kidney disease: the Quality Improvement in CKD (QICKD) trial results

Strict control of systolic blood pressure is known to slow progression of chronic kidney disease (CKD). Here we compared audit-based education (ABE) to guidelines and prompts or usual practice in lowering systolic blood pressure in people with CKD. This 2-year cluster randomized trial included 93 volunteer general practices randomized into three arms with 30 ABE practices, 32 with guidelines and prompts, and 31 usual practices. An intervention effect on the primary outcome, systolic blood pressure, was calculated using a multilevel model to predict changes after the intervention. The prevalence of CKD was 7.29% (41,183 of 565,016 patients) with all cardiovascular comorbidities more common in those with CKD. Our models showed that the systolic blood pressure was significantly lowered by 2.41 mm Hg (CI 0.59–4.29 mm Hg), in the ABE practices with an odds ratio of achieving at least a 5 mm Hg reduction in systolic blood pressure of 1.24 (CI 1.05–1.45). Practices exposed to guidelines and prompts produced no significant change compared to usual practice. Male gender, ABE, ischemic heart disease, and congestive heart failure were independently associated with a greater lowering of systolic blood pressure but the converse applied to hypertension and age over 75 years. There were no reports of harm. Thus, individuals receiving ABE are more likely to achieve a lower blood pressure than those receiving only usual practice. The findings should be interpreted with caution due to the wide confidence intervals.

Royal College of General Practitioners Research and Surveillance Centre (RCGP RSC) sentinel network: a cohort profile

Purpose The Royal College of General Practitioners Research and Surveillance Centre (RCGP RSC) is one of the longest established primary care sentinel networks. In 2015, it established a new data and analysis hub at the University of Surrey. This paper evaluates the representativeness of the RCGP RSC network against the English population. Participants and method The cohort includes 1 042 063 patients registered in 107 participating general practitioner (GP) practices. We compared the RCGP RSC data with English national data in the following areas: demographics; geographical distribution; chronic disease prevalence, management and completeness of data recording; and prescribing and vaccine uptake. We also assessed practices within the network participating in a national swabbing programme. Findings to date We found a small over-representation of people in the 25–44 age band, under-representation of white ethnicity, and of less deprived people. Geographical focus is in London, with less practices in the southwest and east of England. We found differences in the prevalence of diabetes (national: 6.4%, RCPG RSC: 5.8%), learning disabilities (national: 0.44%, RCPG RSC: 0.40%), obesity (national: 9.2%, RCPG RSC: 8.0%), pulmonary disease (national: 1.8%, RCPG RSC: 1.6%), and cardiovascular diseases (national: 1.1%, RCPG RSC: 1.2%). Data completeness in risk factors for diabetic population is high (77–99%). We found differences in prescribing rates and costs for infections (national: 5.58%, RCPG RSC: 7.12%), and for nutrition and blood conditions (national: 6.26%, RCPG RSC: 4.50%). Differences in vaccine uptake were seen in patients aged 2 years (national: 38.5%, RCPG RSC: 32.8%). Owing to large numbers, most differences were significant (p<0.00015). Future plans The RCGP RSC is a representative network, having only small differences with the national population, which have now been quantified and can be assessed for clinical relevance for specific studies. This network is a rich source for research into routine practice.

Serum Phosphate as a Risk Factor for Cardiovascular Events in People with and without Chronic Kidney Disease: A Large Community Based Cohort Study

Background Serum phosphate is a known risk factor for cardiovascular events and mortality in people with chronic kidney disease (CKD), however data on the association of these outcomes with serum phosphate in the general population are scarce. We investigate this relationship in people with and without CKD in a large community-based population. Methods Three groups from an adult cohort of the Quality Improvement in Chronic Kidney Disease (QICKD) cluster randomised trial (ISRCTN56023731) were followed over a period of 2.5 years: people with normal renal function (N = 24,184), people with CKD stages 1–2 (N = 20,356), and people with CKD stages 3–5 (N = 13,292). We used a multilevel logistic regression model to determine the association between serum phosphate, in these groups, and a composite outcome of all-cause mortality, cardiovascular events, and advanced coronary artery disease. We adjusted for known cardiovascular risk factors. Findings Higher phosphate levels were found to correlate with increased cardiovascular risk. In people with normal renal function and CKD stages 1–2, Phosphate levels between 1.25 and 1.50 mmol/l were associated with increased cardiovascular events; odds ratio (OR) 1.36 (95% CI 1.06–1.74; p = 0.016) in people with normal renal function and OR 1.40 (95% CI 1.09–1.81; p = 0.010) in people with CKD stages 1–2. Hypophosphatemia (<0.75 mmol/l) was associated with fewer cardiovascular events in people with normal renal function; OR 0.59 (95% CI 0.36–0.97; p = 0.049). In people with CKD stages 3–5, hyperphosphatemia (>1.50 mmol/l) was associated with increased cardiovascular risk; OR 2.34 (95% CI 1.64–3.32; p<0.001). Other phosphate ranges were not found to have a significant impact on cardiovascular events in people with CKD stages 3–5. Conclusions Serum phosphate is associated with cardiovascular events in people with and without CKD. Further research is required to determine the mechanisms underlying these associations.

Diabetes screening after gestational diabetes in England: a quantitative retrospective cohort study

BACKGROUND The National Institute for Health and Care Excellence (NICE) recommends postpartum and annual monitoring for diabetes for females who have had a diagnosis of gestational diabetes mellitus (GDM). AIM To describe the current state of follow-up after GDM in primary care, in England. DESIGN AND SETTING A retrospective cohort study in 127 primary care practices. The total population analysed comprised 473 772 females, of whom 2016 had a diagnosis of GDM. METHOD Two subgroups of females were analysed using electronic general practice records. In the first group of females (n = 788) the quality of postpartum follow-up was assessed during a 6-month period. The quality of long-term annual follow-up was assessed in a second group of females (n = 718), over a 5-year period. The two outcome measures were blood glucose testing performed within 6 months postpartum (first group) and blood glucose testing performed annually (second group). RESULTS Postpartum follow-up was performed in 146 (18.5%) females within 6 months of delivery. Annual rates of long-term follow-up stayed consistently around 20% a year. Publication of the Diabetes in Pregnancy NICE guidelines, in 2008, had no effect on long-term screening rates. Substantial regional differences were identified among rates of follow-up. CONCLUSION Monitoring of females after GDM is markedly suboptimal despite current recommendations.

A study of cardiovascular risk in overweight and obese people in England

Objectives: To report current levels of obesity and associated cardiac risk using routinely collected primary care computer data. Methods: 67 practices took part in an educational intervention to improve computer data quality and care in cardiovascular disease. Data were extracted from 435 102 general practice computer records. 64.3% (229 108/362 861) of people age 15 y and older had a body mass index (BMI) recording or a valid height and weight record that enabled BMI to be derived. Data about cardiovascular disease and risk factors were also extracted. The prevalence of disease and the control of risk factors in the overweight and obese population were compared with those of normal body weight. Results: 56.8% of men and 69.3% of women aged over 15 y had a BMI record. 22% of men and 32.3% of women aged 15 to 24 y were overweight or obese; rising each decade to a peak of 65.6% of men and 57.5% of women aged 55 to 64 y. Thereafter, the proportion who were overweight or obese declined. The prevalence of ischaemic heart disease, diabetes mellitus and hypertension rose with increasing levels of obesity; their prevalence in those who are moderately obese was between two and three times that of the general population. Systolic and diastolic blood pressure, blood glucose even in non-diabetics, cholesterol and triglycerides were all elevated in the overweight and obese population. Conclusion: Based on the recorded data over half of men and nearly half of women are overweight or obese. They have increased cardiovascular risk, which is not adequately controlled by current practice.

Confidence and quality in managing CKD compared with other cardiovascular diseases and diabetes mellitus: a linked study of questionnaire and routine primary care data

BackgroundMuch of chronic disease is managed in primary care and chronic kidney disease (CKD) is a recent addition. We are conducting a cluster randomised study of quality improvement interventions in CKD (QICKD) - Clinical Trials Registration: ISRCTN56023731. CKD registers have a lower than expected prevalence and an initial focus group study suggested variable levels of confidence in managing CKD.Our objective is to compare practitioner confidence and achievement of quality indicators for CKD with hypertension and diabetes.MethodWe validated a new questionnaire to test confidence. We compared confidence with achievement of pay-for-performance indicators (P4P) and implementation of evidence-based guidance. We achieved a 74% (148/201) response rate.Results87% (n = 128) of respondents are confident in managing hypertension (HT) compared with 59% (n = 87) in managing HT in CKD (HT+CKD); and with 61% (n = 90) in HT, CKD and diabetes (CKD+HT+DM).85.2% (P4P) and 62.5% (National targets) of patients with hypertension are at target; in patients with HT and CKD 65.1% and 53.3%; in patients with HT, CKD and DM 67.8% and 29.6%.Confidence in managing proteinuria in CKD is low (42%, n = 62). 87% of respondents knew BP treatment thresholds in CKD, but only 53% when proteinuria is factored in. Male GPs, younger (< 35 yrs), and older (> 54 yrs) clinicians are more confident than females and 35 to 54 year olds in managing CKD.84% of patients with hypertension treated with angiotensin modulating drugs achieve achieved P4P targets compared to 67% of patients with CKD.ConclusionsPractitioners are less likely to achieve management targets where their confidence is low.

Measuring the impact of the computer on the consultation: an open source application to combine multiple observational outputs.

A diverse range of tools and techniques can be used to observe the clinical consultation and the use of information technology. These technologies range from transcripts; to video observation with one or more cameras; to voice and pattern recognition applications. Currently, these have to be observed separately and there is limited capacity to combine them. Consequently, when multiple methods are used to analyse the consultation a significant proportion of time is spent linking events in one log file (e.g. mouse movements and keyboard use when prescribing alerts appear) with what was happening in the consultation at that time. The objective of this study was to develop an application capable of combining and comparing activity log-files and with facilities to view simultaneously all data relating to any time point or activity. Interviews, observations and design prototypes were used to develop a specification. Class diagram of the application design was used to make further development decisions. The application development used object-orientated design principles. We used open source tools; Java as the programming language and JDeveloper™ as the development environment. The final output is log file aggregation (LFA) tool which forms part of the wider aggregation of log files for analysis (ALFA) open source toolkit (www.biomedicalinformatics.info/alfa/). Testing was done using sample log files and reviewed the applications utility for analysis of the consultation activities. Separation of the presentation and functionality in the design stage enabled us to develop a modular and extensible application. The application is capable of converting and aggregating several log files of different formats and displays them in different presentation layouts. We used the Java Media Framework to aggregate video channels. Java extensible mark-up language (XML) package facilitated the conversion of aggregated output into XML format. Analysts can now move easily between observation tools and find all the data related to an activity. The LFA application makes new analysis tasks feasible and established tasks much more efficient. Researchers can now store multiple log file data as a single file isolate and investigate different doctor–computer–patient interaction.

Abnormal lipids in high-risk patients achieving cholesterol targets: a cross-sectional study of routinely collected UK general practice data

ABSTRACT Background and objectives: Lipid management in UK general practice targets the achievement of total cholesterol (TC) targets in high-risk individuals. Statins alone have a modest effect on non-LDL-C components of the lipid profile, leaving these patients at significant residual cardiovascular (CV) risk. Improving risk further would require the addition of non-statin therapies. This analysis explores what proportion of the UK population with cardiovascular disease (CVD) and TC levels at or below target may still be at risk because of residual dyslipidaemia. Methods: CV risk profiles were extracted from a research database of 602 222 patients from 98 UK general practices. Patients were categorised according to their prior CV history and use of statins. Mean values and proportions achieving treatment targets were assessed for TC, low density lipoprotein (LDL-C), high density lipoprotein (HDL-C) and triglycerides (TG). Results: In all, 48 499 patients with pre-existing CVD or diabetes were identified. 73% of statin-treated patients and 63% of untreated patients had a TC ≤ 5 mmol/L. 28.6% of patients treated to a TC target had LDL-C > 3 mmol/L. Amongst those with both TC and LDL-C treated to target, 22.5% had low HDL-C and 37.2% had high triglyceride (TG). Within this group, more women than men had abnormal HDL-C (25.4 vs. 20.7% p < 0.0001). Patients with diabetes were more likely than non-diabetics to have abnormalities of both HDL-C (28.9 vs. 16.4% p < 0.0001) and triglyceride (44.9 vs. 29.5% p < 0.0001) despite normal TC and LDL-C. Conclusions: Around 60% of high-risk patients have residual dyslipidaemias despite achieving the Quality and Outcomes Framework (QOF) TC target. New patterns of treatment are required in order to extend lipid management beyond simple total cholesterol lowering.