Suboptimal blood pressure control in chronic kidney disease stage 3: baseline data from a cohort study in primary care

Antihypertensive prescribing patterns in non-dialysis dependent chronic kidney disease: Findings from the Salford Kidney Study

BACKGROUND

Hypertension is commonly observed in patients living with chronic kidney disease (CKD). Finding an optimal treatment regime remains challenging due to the complex bidirectional cause-and-effect relationship between hypertension and CKD. There remains variability in antihypertensive treatment practices.

AIM

To analyze data from the Salford Kidney Study database in relation to antihypertensive prescribing patterns amongst CKD patients.

METHODS

The Salford Kidney Study is an ongoing prospective study that has been recruiting CKD patients since 2002. All patients are followed up annually, and their medical records including the list of medications are updated until they reach study endpoints [starting on renal replacement therapy or reaching estimated glomerular filtration rate (eGFR) expressed as mL/min/1.73 m2 ≤ 10 mL/min/1.73 m2, or the last follow-up date, or data lock on December 31, 2021, or death]. Data on antihypertensive prescription practices in correspondence to baseline eGFR, urine albumin-creatinine ratio, primary CKD aetiology, and cardiovascular disease were evaluated. Associations between patients who were prescribed three or more antihypertensive agents and their clinical outcomes were studied by Cox regression analysis. Kaplan-Meier analysis demonstrated differences in survival probabilities.

RESULTS

Three thousand two hundred and thirty non-dialysis-dependent CKD patients with data collected between October 2002 and December 2019 were included. The median age was 65 years. A greater proportion of patients were taking three or more antihypertensive agents with advancing CKD stages (53% of eGFR ≤ 15 mL/min/1.73 m2 vs 26% of eGFR ≥ 60 mL/min/1.73 m2, P < 0.001). An increased number of patients receiving more classes of antihypertensive agents was observed as the urine albumin-creatinine ratio category increased (category A3: 62% vs category A1: 40%, P < 0.001), with the upward trends particularly noticeable in the number of individuals prescribed renin angiotensin system blockers. The prescription of three or more antihypertensive agents was associated with all-cause mortality, independent of blood pressure control (hazard ratio: 1.15; 95% confidence interval: 1.04-1.27, P = 0.006). Kaplan-Meier analysis illustrated significant differences in survival outcomes between patients with three or more and those with less than three antihypertensive agents prescribed (log-rank, P < 0.001).

CONCLUSION

Antihypertensive prescribing patterns in the Salford Kidney Study based on CKD stage were consistent with expectations from the current United Kingdom National Institute of Health and Care Excellence guideline algorithm. Outcomes were poorer in patients with poor blood pressure control despite being on multiple antihypertensive agents. Continued research is required to bridge remaining variations in hypertension treatment practices worldwide.

Associations with age and glomerular filtration rate in a referred population with chronic kidney disease: methods and baseline data from a UK multicentre cohort study (NURTuRE-CKD)

BACKGROUND

Chronic kidney disease (CKD) is common but heterogenous and is associated with multiple adverse outcomes. The National Unified Renal Translational Research Enterprise (NURTuRE)-CKD cohort was established to investigate risk factors for clinically important outcomes in persons with CKD referred to secondary care.

METHODS

Eligible participants with CKD stages G3-4 or stages G1-2 plus albuminuria >30 mg/mmol were enrolled from 16 nephrology centres in England, Scotland and Wales from 2017 to 2019. Baseline assessment included demographic data, routine laboratory data and research samples. Clinical outcomes are being collected over 15 years by the UK Renal Registry using established data linkage. Baseline data are presented with subgroup analysis by age, sex and estimated glomerular filtration rate (eGFR).

RESULTS

A total of 2996 participants was enrolled. Median (interquartile range) age was 66 (54-74) years, eGFR 33.8 (24.0-46.6) mL/min/1.73 m2 and urine albumin to creatinine ratio 209 (33-926) mg/g; 58.5% were male. Of these participants, 1883 (69.1%) were in high-risk CKD categories. Primary renal diagnosis was CKD of unknown cause in 32.3%, glomerular disease in 23.4% and diabetic kidney disease in 11.5%. Older participants and those with lower eGFR had higher systolic blood pressure and were less likely to be treated with renin-angiotensin system inhibitors (RASi) but were more likely to receive a statin. Female participants were less likely to receive a RASi or statin.

CONCLUSIONS

NURTuRE-CKD is a prospective cohort of persons who are at relatively high risk of adverse outcomes. Long-term follow-up and a large biorepository create opportunities for research to improve risk prediction and to investigate underlying mechanisms to inform new treatment development.

CENtral blood pressure Targeting: a pragmatic RAndomized triaL in advanced Chronic Kidney Disease (CENTRAL-CKD): A Clinical Research Protocol

Background

Emerging data favor central blood pressure (BP) over brachial cuff BP to predict cardiovascular and kidney events, as central BP more closely relates to the true aortic BP. Considering that patients with advanced chronic kidney disease (CKD) are at high cardiovascular risk and can have unreliable brachial cuff BP measurements (due to high arterial stiffness), this population could benefit the most from hypertension management using central BP measurements.

Objective

To assess the feasibility and efficacy of targeting central BP as opposed to brachial BP in patients with CKD G4-5.

Design

Pragmatic multicentre double-blinded randomized controlled pilot trial.

Setting

Seven large academic advanced kidney care clinics across Canada.

Patients

A total of 116 adults with CKD G4-5 (estimated glomerular filtration rate [eGFR] < 30 mL/min) and brachial cuff systolic BP between 120 and 160 mm Hg. The key exclusion criteria are 1) ≥ 5 BP drugs, 2) recent acute kidney injury, myocardial infarction, stroke, heart failure or injurious fall, 3) previous kidney replacement therapy.

Methods

Double-blind randomization to a central or a brachial cuff systolic BP target (both < 130 mm Hg) as measured by a validated central BP device. The study duration is 12 months with follow-up visits every 2 to 4 months, based on local practice. All other aspects of CKD management are at the discretion of the attending nephrologist.

Outcomes

Primary Feasibility: Feasibility of a large-scale trial based on predefined components. Primary Efficacy: Carotid-femoral pulse wave velocity at 12 months. Others: Efficacy (eGFR decline, albuminuria, BP drugs, and quality of life); Events (major adverse cardiovascular events, CKD progression, hospitalization, mortality); Safety (low BP events and acute kidney injury).

Limitations

May be challenging to distinguish whether central BP is truly different from brachial BP to the point of significantly influencing treatment decisions. Therapeutic inertia may be a barrier to successfully completing a randomized trial in a population of CKD G4-5. These 2 aspects will be evaluated in the feasibility assessment of the trial.

Conclusion

This is the first trial to evaluate the feasibility and efficacy of using central BP to manage hypertension in advanced CKD, paving the way to a future large-scale trial.

Trial registration

clinicaltrials.gov (NCT05163158).

Blood Pressure Control and its Determinants among Patients with Chronic Kidney Disease in a Nigerian Tertiary Hospital: A Cross-Sectional Study

Background

Hypertension is a common cardiovascular risk factor associated with adverse renal and cardiovascular outcomes in chronic kidney disease patients. Significant reduction in these adverse outcomes could be achieved through adequate blood pressure control in those with hypertension. This study aimed to determine the prevalence of poor blood pressure control and associated factors among chronic kidney disease patients with hypertension in a Nigerian tertiary hospital.

Methodology

This was a cross-sectional study that determined the prevalence of poor blood pressure control and its associated factors among chronic kidney disease patients with hypertension. Poor blood pressure control was defined as blood pressure ≥ 140/90mmHg. Factors associated with blood pressure control were determined on multivariate analysis. P-value less than 0.05 was considered significant.

Results

A total of 494 chronic kidney disease patients with hypertension were studied. The mean age of patients was 48.77+13.06 with a range of 17-95 years. There were 303 (61.3%) males and 191 (38.7%) females. A total of 44.5% of the patients had end-stage renal disease while all patients were on antihypertensive medications. The common causes of chronic kidney disease were hypertension (35%), diabetes mellitus (26.5%), and chronic glomerulonephritis (12.1%).Poor blood pressure control was found in 74.4% of chronic kidney disease patients. The predictors of poor blood pressure control were age (AOR: 0.65; CI: 0.45-0.94; p=0.02), use of multiple anti-hypertensives (AOR: 1.99; CI: 1.36-2.90; p=<0.001) and the presence of significant proteinuria (AOR: 1.47; CI: 1.02-2.14; p=0.04).

Conclusion

The majority of patients with chronic kidney disease had poor blood pressure control. Those who were young had significant proteinuria, and those who used≥ 3 antihypertensive medications were more likely to have poor blood control. There is a need to optimize BP management in chronic kidney disease patients in order to reduce adverse outcomes.

Hypertension and cardiovascular risk factor management in a multi-ethnic cohort of adults with CKD: a cross sectional study in general practice

Background

Hypertension, especially if poorly controlled, is a key determinant of chronic kidney disease (CKD) development and progression to end stage renal disease (ESRD).

Aim

To assess hypertension and risk factor management, and determinants of systolic blood pressure control in individuals with CKD and hypertension.

Design and setting

Cross-sectional survey using primary care electronic health records from 47/49 general practice clinics in South London.

Methods

Known effective interventions, management of hypertension and cardiovascular disease (CVD) risk in patients with CKD Stages 3–5 were investigated. Multivariable logistic regression analysis examined the association of demographic factors, comorbidities, deprivation, and CKD coding, with systolic blood pressure control status as outcome. Individuals with diabetes were excluded.

Results

Adults with CKD Stages 3–5 and hypertension represented 4131/286,162 (1.4%) of the total population; 1984 (48%) of these individuals had undiagnosed CKD without a recorded CKD clinical code. Hypertension was undiagnosed in 25% of the total Lambeth population, and in patients with CKD without diagnosed hypertension, 23.0% had systolic blood pressure > 140 mmHg compared with 39.8% hypertensives, p < 0.001. Multivariable logistic regression revealed that factors associated with improved systolic blood pressure control in CKD included diastolic blood pressure control, serious mental illness, history of cardiovascular co-morbidities, CKD diagnostic coding, and age < 60 years. African ethnicity and obesity were associated with poorer systolic blood pressure control.

Conclusion

We found both underdiagnosed CKD and underdiagnosed hypertension in patients with CKD. The poor systolic blood pressure control in older age groups ≥ 60 years and in Black African or obese individuals is clinically important as these groups are at increased risk of mortality for cardiovascular diseases.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40620-021-01149-0.

Determinants of change in arterial stiffness over 5 years in early chronic kidney disease

BACKGROUND

Arterial stiffness (AS) is an established and potentially modifiable risk factor for cardiovascular disease associated with chronic kidney disease (CKD). There have been few studies to evaluate the progression of AS over time or factors that contribute to this, particularly in early CKD. We therefore investigated AS over 5 years in an elderly population with CKD Stage 3 cared for in primary care.

METHODS

A total of 1741 persons with an estimated glomerular filtration rate of 30-59 mL/min/1.73 m2 underwent detailed clinical and biochemical assessment at baseline and Years 1 and 5. Carotid to femoral pulse wave velocity (PWV) was measured to assess AS using a Vicorder device.

RESULTS

970 participants had PWV assessments at baseline and 5 years. PWV increased significantly by a mean of 1.1 m/s (from 9.7 ± 1.9 to 10.8 ± 2.1 m/s). Multivariable linear regression analysis identified the following independent determinants of ΔPWV at Year 5: baseline age, diabetes status, baseline systolic blood pressure (SBP) and diastolic blood pressure, baseline PWV, ΔPWV at 1 year, ΔSBP over 5 years and Δserum bicarbonate over 5 years (R2 = 0.38 for the equation).

CONCLUSIONS

We observed a clinically significant increase in PWV over 5 years in a cohort with early CKD despite reasonably well-controlled hypertension. Measures of BP were identified as the most important modifiable determinant of ΔPWV, suggesting that interventions to prevent arterial disease should focus on improved control of BP, particularly in those who evidence an early increase in PWV. These hypotheses should now be tested in prospective trials.

Impact of superimposed nephrological care to guidelines-directed management by primary care physicians of patients with stable chronic kidney disease: a randomized controlled trial

BACKGROUND

Optimal clinical care of patients with chronic kidney disease (CKD) requires collaboration between primary care physicians (PCPs) and nephrologists. We undertook a randomised trial to determine the impact of superimposed nephrologist care compared to guidelines-directed management by PCPs in CKD patients after hospital discharge.

METHODS

Stage 3b-4 CKD patients were enrolled during a hospitalization and randomised in two arms: Co-management by PCPs and nephrologists (interventional arm) versus management by PCPs with written instructions and consultations by nephrologists on demand (standard care). Our primary outcome was death or rehospitalisation within the 2 years post-randomisation. Secondary outcomes were: urgent renal replacement therapy (RRT), decline of renal function and decrease of quality of life at 2 years.

RESULTS

From November 2009 to the end of June 2013, we randomised 242 patients. Mean follow-up was 51 + 20 months. Survival without rehospitalisation, GFR decline and elective dialysis initiation did not differ between the two arms. Quality of life was also similar in both groups. Compared to randomised patients, those who either declined to participate in the study or were previously known by nephrologists had a worse survival.

CONCLUSION

These results do not demonstrate a benefit of a regular renal care compared to guided PCPs care in terms of survival or dialysis initiation in CKD patients. Increased awareness of renal disease management among PCPs may be as effective as a co-management by PCPs and nephrologists in order to improve the prognosis of moderate-to-severe CKD.

TRIAL REGISTRATION

This study was registered on June 29, 2009 in clinicaltrials.gov (NCT00929760) and adheres to CONSORT 2010 guidelines.

Rate of uncontrolled blood pressure and its associated factors in patients with predialysis chronic kidney disease in Bali, Indonesia

Purpose

Hypertension is a key determinant for the development and progression of chronic kidney disease (CKD). The purpose of this study is to assess the rate of uncontrolled blood pressure (BP) and identify its associated factors in patients with predialysis CKD in Bali, Indonesia.

Design/methodology/approach

A cross-sectional study was conducted among 165 patients who attended the nephrology clinic in a central public hospital in Bali. Data were obtained by measuring BP at threshold 130/80 mmHg, as well as collected through standardized questionnaires. Univariate analysis was done using Chi-square test, and multivariate analyses were carried out using multiple logistic regression.

Findings

A total of 165 patients (111 males and 54 females) with predialysis CKD participated in this study. About 64% of the participants had uncontrolled BP. In multiple logistic regression, all selected variables significantly explained 63.2% of the variance in uncontrolled BP. However, low physical activity (odds ratio [OR] = 24.287, 95% confidence interval [CI]: 3.114–189.445), unhealthy dietary pattern (OR = 10.153, 95% CI: 2.770–37.210), as well as perceived moderate stress (OR = 4.365, 95% CI: 1.024-18.609) and high stress (OR = 10.978, 95% CI: 2.602–46.312) were significantly associated with uncontrolled BP.

Research limitations/implications

The study findings provide evidence for health care providers to improve BP control among patients with predialysis CKD.

Originality/value

Controlling BP among patients with predialysis CKD was poor. Lifestyle modification and stress management are keys to improving BP control.

Association of Time-Varying Blood Pressure With Chronic Kidney Disease Progression in Children

IMPORTANCE

Optimal blood pressure (BP) management in children with chronic kidney disease (CKD) slows progression to end-stage renal disease. Studies often base progression risk on a single baseline BP measurement, which may underestimate risk.

OBJECTIVE

To determine whether time-varying BP measurements are associated with a higher risk of progression of CKD than baseline BP measurements.

DESIGN, SETTING, AND PARTICIPANTS

The ongoing longitudinal, prospective cohort study Chronic Kidney Disease in Children (CKID) recruited children from January 19, 2005, through March 19, 2014, from pediatric nephrology centers across North America, with data collected at annual study visits. Participants included children aged 1 to 16 years with a diagnosis of CKD and a glomerular filtration rate (GFR) of 30 to 90 mL/min/1.73 m2. Data were analyzed from February 11, 2005, through February 13, 2018.

EXPOSURES

Office BP measurement classified as less than 50th percentile, 50th to less than 90th percentile, or at least 90th percentile. Blood pressure categories were treated as time fixed (baseline) or time varying (updated at each visit) in models.

MAIN OUTCOMES AND MEASURES

A composite renal outcome (50% GFR reduction from baseline, estimated GFR less than 15 mL/min/1.73 m2, or dialysis or transplant). Pooled logistic models using inverse probability weighting estimated the hazard odds ratio (HOR) of the composite outcome associated with each BP category stratified by CKD diagnosis.

RESULTS

A total of 844 children (524 [62.1%] male; median age, 11 [interquartile range, 8-15] years; 151 [17.9%] black; 580 [68.7%] with nonglomerular CKD; and 264 [31.3%] with glomerular CKD) with complete baseline data and median follow-up of 4 (interquartile range, 2-6) years were included. One hundred ninety-six participants with nonglomerular diagnoses (33.8%) and 99 with glomerular diagnoses (37.5%) reached the composite outcome. Baseline systolic BP in at least the 90th percentile was associated with a higher risk of the composite outcome (HOR for nonglomerular disease, 1.58 [95% CI, 1.07-2.32]; HOR for glomerular disease, 2.85 [95% CI, 1.64-4.94]) compared with baseline systolic BP in less than the 50th percentile. Time-fixed estimates were substantially lower compared with time-varying systolic BP percentile categories (HOR among those with nonglomerular CKD, 3.75 [95% CI, 2.53-5.57]; HOR among those with glomerular diagnoses, 5.96 [95% CI, 3.37-10.54]) comparing those at or above the 90th percentile vs below the 50th percentile. Adjusted models (adjusted for proteinuria and use of antihypertensives) attenuated the risk in nonglomerular CKD (adjusted HOR for baseline measurement, 1.52 [95% CI, 0.98-2.36]; adjusted HOR for time-varying measurement, 2.25 [95% CI, 1.36-3.72]) and in glomerular CKD (adjusted HOR for baseline, 0.97 [95% CI, 0.39-2.36]; adjusted HOR for time-varying measurement, 1.41 [95% CI, 0.65-3.03]). Similar results were observed for diastolic BP.

CONCLUSIONS AND RELEVANCE

Among children with nonglomerular CKD included in this study, elevated time-varying BP measurements were associated with a greater risk of CKD progression compared with baseline BP measurement. This finding suggests that previous studies using only baseline BP likely underestimated the association between BP and CKD progression.

Cardiovascular changes in patients with mild-to-moderate chronic kidney disease compared with healthy subjects: a 5-year follow-up study

BACKGROUND

There is limited knowledge about how cardiovascular parameters change over time in patients with mild-to-moderate chronic kidney disease (CKD). We studied several cardiovascular biomarkers over a 5-year period in patients with mild-to-moderate CKD and in healthy controls.

METHODS

Fifty-four patients with CKD stages 2-3 and 54 controls were included. The CKD patients were closely monitored and well controlled for hypertension and other cardiovascular risk factors. Ambulatory blood pressure (BP) monitoring, ankle-brachial index (ABI), carotid and cardiac ultrasound (including measurement of the left ventricular mass index (LVMI)), and biochemical analyses were evaluated.

RESULTS

Renal function decreased in both groups, with no significant difference in the change over time. In the CKD patients, none of the BP variables increased over time, but in the controls, average 24-h and daytime systolic BP increased significantly. ABI increased slightly in the CKD patients (P<0·001), but not in the controls (P = 0·963), and phosphate had a significant positive effect on ABI. Although in the CKD patients, there was no significant increase over time in common carotid artery diameter (P = 0·274), there was a small but significant increase in the controls (P = 0·001). LVMI increased significantly over time in both groups.

CONCLUSIONS

In our study of patients with mild-to-moderate CKD, the progression of cardiovascular changes over time was relatively slow. Good BP control and treatment of other risk factors may have contributed to slow the progress of cardiovascular involvement, which emphasizes the importance of dedicated care in this population.

Considerable international variation exists in blood pressure control and antihypertensive prescription patterns in chronic kidney disease

Although blood pressure control is a major goal in chronic kidney disease, no worldwide overview of either its achievement or antihypertensive prescriptions is currently available. To evaluate this we compared crude prevalence of uncontrolled blood pressure among 17 cohort studies, including 34 602 individuals with estimated glomerular filtration rate under 60 ml/min/1.73 m² and treated hypertension across four continents, and estimated observed to expected prevalence ratios, adjusted for potential confounders. Crude prevalence of blood pressure of 140/90 mm Hg or more varied from 28% to 61% and of blood pressure of 130/80 or more from 54% to 84%. Adjusted prevalence ratios indicated poorer hypertension control than expected in cohorts from European countries, India, and Uruguay, and better control in patients from North American and high-income Asian countries. Four antihypertensive drug classes or more were prescribed to more than 30% of participants in North American and some European cohorts, but this practice was less common elsewhere. Renin angiotensin-aldosterone system inhibitors were the most common antihypertensive drugs, prescribed for 54% to 91% of cohort participants. Differences for other drug classes were much stronger, ranging from 11% to 79% for diuretics, 22% to 70% for beta-blockers, and 27% to 75% for calcium-channel blockers. The confounders studied explain only a part of the international variation in blood pressure control among individuals with chronic kidney disease. Thus, considerable heterogeneity in prescription patterns worldwide calls for further investigation into the impact of different approaches on patient outcomes.

Antihypertensive therapy prescribing patterns and correlates of blood pressure control among hypertensive patients with chronic kidney disease

We used electronic health records (EHRs) data from 5658 ambulatory chronic kidney disease (CKD) patients with hypertension and prescribed antihypertensive therapy to examine antihypertensive drug prescribing patterns, blood pressure (BP) control, and risk factors for resistant hypertension (RHTN) in a real-world setting. Two-thirds of CKD patients and three-fourths of those with proteinuria were prescribed guideline-recommended renoprotective agents including an angiotensin-converting enzyme inhibitor (ACEI) or an angiotensin receptor blocker (ARB); however, one-third were not prescribed an ACEI or ARB. CKD patients, particularly those with stages 1-2 CKD, who were prescribed regimens including beta-blocker (BB) + diuretic or ACEI/ARB + BB + diuretic were more likely to have controlled BP (<140/90 mm Hg) compared to those prescribed other combinations. Risk factors for RHTN included African American race and major comorbidities. Clinicians may use these findings to tailor antihypertensive therapy to the needs of each patient, including providing CKD stage-specific treatment, and better identify CKD patients at risk of RHTN.

Sodium Intake and Blood Pressure in Patients with Chronic Kidney Disease: A Salty Relationship

BACKGROUND

Hypertension affects almost all chronic kidney disease patients and is related to poor outcomes. Sodium intake is closely related to blood pressure (BP) levels in this population and decreasing its intake consistently improves the BP control particularly in short-term controlled trials. However, most patients struggle in following a controlled diet on sodium according to the guidelines recommendation due to several factors and barriers discussed in this article.

SUMMARY

This review article summarizes the current knowledge related to the associations between sodium consumption, BP, and the risk of cardiovascular disease and chronic kidney disease (CKD); it also provides recommendations of how to achieve sodium intake lowering. Key Messages: Evidences support the benefits in decreasing sodium intake on markers of cardiovascular and renal outcomes in CKD. Trials had shorter follow-up and to maintain long-term sodium intake control is a major challenge. Larger studies with longer follow-up looking at hard endpoints will be important to drive future recommendations.

Chronic kidney disease in hypertensive subjects ≥60 years treated in Primary Care

BACKGROUND

Hypertension (HT) is the second leading cause of kidney failure. In hypertensive patients with chronic kidney disease (CKD), blood pressure (BP) control is the most important intervention to minimise progression. For CKD diagnosis, standardised creatinine and estimated glomerular filtration rate (eGFR) testing by CKD-EPI is recommended.

OBJECTIVES

To describe the prevalence and factors associated with a moderate decrease in eGFR (by CKD-EPI) and BP control in subjects with HT.

METHODS

Cross-sectional descriptive study in subjects ≥ 60 years included in the SIDIAP plus database with hypertension and standardised serum creatinine and BP tests in the last 2years.

EXCLUSION CRITERIA

eGFR<30, dialysis or kidney transplantation, prior cardiovascular disease, home care. Primary endpoint: eGFR by CKD-EPI formula. Covariates: demographic data, examination, cardiovascular risk factors, heart failure and auricular fibrillation diagnosis, and drugs (antihypertensive agents acting on renal function, antiplatelet and lipid lowering agents). BP control criteria: ≤130/80mmHg in individuals with albuminuria, ≤140/90 in all other subjects.

RESULTS

Prevalence of eGFR <60=18.8%. Associated factors: age, gender, heart failure, albumin/creatinine ratio, auricular fibrillation, smoking, dyslipidaemia, diabetes and obesity. BP control: 66.14 and 63.24% in eGFR≥60 and eGFR <60, respectively (P<.05). Exposure to drugs was higher in eGFR<60.

CONCLUSION

One in 5hypertensive patients without cardiovascular disease ≥60 years in primary care presented with a moderate decrease in eGFR. In addition to age and sex, albuminuria and heart failure were the main associated factors. Despite the increased exposure to drugs, BP control was lower in CKD.

Hypertension and blood pressure variability management practices among physicians in Singapore

Purpose

There are limited data on blood pressure variability (BPV) in Singapore. The absence of updated local guidelines might contribute to variations in diagnosis, treatment and control of hypertension and BPV between physicians. This study evaluated BPV awareness, hypertension management and associated training needs in physicians from Singapore.

Materials and methods

Physicians from Singapore were surveyed between September 8, 2016, and October 5, 2016. Those included were in public or private practice for ≥3 years, cared directly for patients ≥70% of the time and treated ≥30 patients for hypertension each month. The questionnaire covered 6 main categories: general blood pressure (BP) management, BPV awareness/diagnosis, home BP monitoring (HBPM), ambulatory BP monitoring (ABPM), BPV management and associated training needs.

Results

Responses from 60 physicians (30 general practitioners [GPs], 20 cardiologists, 10 nephrologists) were analyzed (77% male, 85% aged 31–60 years, mean 22 years of practice). Approximately 63% of physicians considered white-coat hypertension as part of BPV. The most common diagnostic tool was HBPM (overall 77%, GPs 63%, cardiologists 65%, nephrologists 70%), but ABPM was rated as the tool most valued by physicians (80% overall), especially specialists (97%). Withdrawn Singapore guidelines were still being used by 73% of GPs. Approximately 48% of physicians surveyed did not adhere to the BP cutoff recommended by most guidelines for diagnosing hypertension using HBPM (>135/85 mmHg). Hypertension treatment practices also varied from available guideline recommendations, although physicians did tend to use a lower BP target for patients with diabetes or kidney disease. There were a number of challenges to estimating BPV, the most common of which was patient refusal of ABPM/HBPM. The majority of physicians (82%) had no training on BPV, but stated that this would be useful.

Conclusion

There appear to be gaps in knowledge and guideline adherence relating to the assessment and management of BPV among physicians in Singapore.

Target Organ Damage and the Long Term Effect of Nonadherence to Clinical Practice Guidelines in Patients with Hypertension: A Retrospective Cohort Study

Background

There was limited published data on target organ damage (TOD) and the effect of nonadherence to practice guidelines in Ethiopia. This study determined TOD and the long term effect of nonadherence to clinical guidelines on hypertensive patients.

Methods

An open level retrospective cohort study has been employed at cardiac clinic of Gondar university hospital for a mean follow-up period of 78 months. Multivariate Cox regression was conducted to test associating factors of TOD.

Results

Of the total number of 612 patients examined, the overall prevalence of hypertensive TOD was 40.3%. The presence of comorbidities, COR = 1.073 [1.01–1.437], AOR = 1.196 [1.174–1.637], and nonadherence to clinical practice guidelines, COR = 1.537 [1.167–2.024], AOR = 1.636 [1.189–2.251], were found to be predicting factors for TOD. According to Kaplan-Meier analysis patients who were initiated on appropriate medication tended to develop TOD very late: Log Rank [11.975 (p = 0.01)].

Conclusion

More than forty percent of patients acquired TOD which is more significant. Presence of comorbidities and nonadherence to practice guidelines were correlated with the incidence of TOD. Appropriate management of hypertension and modification of triggering factors are essential to prevent complications.

Improving CKD Diagnosis and Blood Pressure Control in Primary Care: A Tailored Multifaceted Quality Improvement Programme

BACKGROUND

Chronic kidney disease (CKD) is a worldwide public health issue. From 2009 to 2014, the National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care Greater Manchester (NIHR CLAHRC GM) in England ran 4 phased, 12-month quality improvement (QI) projects with 49 primary care practices in GM. Two measureable aims were set - halve undiagnosed CKD in participating practices using modelled estimates of prevalence; and optimise blood pressure (BP) control (<140/90 mm Hg in CKD patients without proteinuria; <130/80 mm Hg in CKD patients with proteinuria) for 75% of recorded cases of CKD. The 4 projects ran as follows: P1 = Project 1 with 19 practices (September 2009 to September 2010), P2 = Project 2 with 11 practices (March 2011 to March 2012), P3 = Project 3 with 12 practices (September 2012 to October 2013), and P4 = Project 4 with 7 practices (April 2013 to March 2014).

METHODS

Multifaceted intervention approaches were tailored based on a contextual analysis of practice support needs. Data were collected from practices by facilitators at baseline and again at project close, with self-reported data regularly requested from practices throughout the projects.

RESULTS

Halving undiagnosed CKD as per aim was exceeded in 3 of the 4 projects. The optimising BP aim was met in 2 projects. Total CKD cases after the programme increased by 2,347 (27%) from baseline to 10,968 in a total adult population (aged ≥18 years) of 231,568. The percentage of patients who managed to appropriate BP targets increased from 34 to 74% (P1), from 60 to 83% (P2), from 68 to 71% (P3), and from 63 to 76% (P4). In nonproteinuric CKD patients, 88, 90, 89, and 91%, respectively, achieved a target BP of <140/90 mm Hg. In proteinuric CKD patients, 69, 46, 48, and 45%, respectively, achieved a tighter target of <130/80 mm Hg. Analysis of national data over similar timeframes indicated that practices participating in the programme achieved higher CKD detection rates.

CONCLUSIONS

Participating practices identified large numbers of "missing" CKD patients with comparator data showing they outperformed non-QI practices locally and nationally over similar timeframes. Improved BP control also occurred through this intervention, but overall achievement of the tighter BP target in proteinuric patients was notably less.

A nationwide cross-sectional survey on prevalence, management and pharmacoepidemiology patterns on hypertension in Chinese patients with chronic kidney disease

Limited data are available on epidemiology and drug use in Chinese hypertensive patients with chronic kidney disease (CKD). We determined the prevalence; awareness, treatment, and control rates of hypertension; anti-hypertensive use, expenditure pattern; and factors associated with hypertension prevalence and control in Chinese patients with CKD. This was one of the largest cross-sectional surveys that enrolled 6079 CKD participants (mean age, 51.0 ± 16.37 years) with or without hypertension from 22 centres across China. The prevalence, awareness, and treatment rates were 71.2%, 95.4%, and 93.7%, respectively. Control rates 1 and 2 (Blood pressure, BP <140/90 and <130/80 mmHg) were 41.1% and 15.0%, respectively. Patients were treated mostly with monotherapy (37.7%) or 2-drug anti-hypertensive combination (38.7%). Factors associated with prevalence of hypertension included age; smoking; body mass index; physical exercise; family history of hypertension; hyperuricaemia; and CKD. Control rate was associated with CKD stage, BP monitoring at home, and use of drug combinations. Despite high rates of awareness and treatment, the control rates are low. CKD stages 4 and 5 adversely affect the control rate. The results suggest the immediate need of comprehensive controlling measures to improve the control of hypertension in Chinese patients with CKD.

Chronic kidney disease: identification and management in primary care

Chronic kidney disease (CKD) is an important and common noncommunicable condition globally. In national and international guidelines, CKD is defined and staged according to measures of kidney function that allow for a degree of risk stratification using commonly available markers. It is often asymptomatic in its early stages, and early detection is important to reduce future risk. The risk of cardiovascular outcomes is greater than the risk of progression to end-stage kidney disease for most people with CKD. CKD also predisposes to acute kidney injury - a major cause of morbidity and mortality worldwide. Although only a small proportion of people with CKD progress to end-stage kidney disease, renal replacement therapy (dialysis or transplantation) represents major costs for health care systems and burden for patients. Efforts in primary care to reduce the risks of cardiovascular disease, acute kidney injury, and progression are therefore required. Monitoring renal function is an important task, and primary care clinicians are well placed to oversee this aspect of care along with the management of modifiable risk factors, particularly blood pressure and proteinuria. Good primary care judgment is also essential in making decisions about referral for specialist nephrology opinion. As CKD commonly occurs alongside other conditions, consideration of comorbidities and patient wishes is important, and primary care clinicians have a key role in coordinating care while adopting a holistic, patient-centered approach and providing continuity. This review aims to summarize the vital role that primary care plays in predialysis CKD care and to outline the main considerations in its identification, monitoring, and clinical management in this context.

The double challenge of resistant hypertension and chronic kidney disease

Resistant hypertension is defined as blood pressure above goal despite adherence to a combination of at least three optimally dosed antihypertensive medications, one of which is a diuretic. Chronic kidney disease is the most frequent of several patient factors or comorbidities associated with resistant hypertension. The prevalence of resistant hypertension is increased in patients with chronic kidney disease, while chronic kidney disease is associated with an impaired prognosis in patients with resistant hypertension. Recommended low-salt diet and triple antihypertensive drug regimens that include a diuretic, should be complemented by the sequential addition of other antihypertensive drugs. New therapeutic innovations for resistant hypertension, such as renal denervation and carotid barostimulation, are under investigation especially in patients with advanced chronic kidney disease. We discuss resistant hypertension in chronic kidney disease stages 3-5 (ie, patients with an estimated glomerular filtration rate below 60 mL/min per 1·73 m(2) and not on dialysis), in terms of worldwide epidemiology, outcomes, causes and pathophysiology, evidence-based treatment, and a call for action.

Effectiveness and clinical inertia in the management of hypertension in patients in Colombia

Determine the effectiveness of treatment and the frequency of clinical inertia in the management of hypertension in Colombian patients. A retrospective study with prospective follow-up of individuals on antihypertensive medication who were treated on medical consultation for 1 year was conducted in 20 Colombian cities. Clinical inertia was considered when no modification of therapy occurred despite not achieving control goals. A total of 355 hypertensive patients were included. From a total of 1142 consultations, therapy was effective in 81.7% of cases. In 18.3% of the cases, the control goal was not achieved, and of these, 81.8% were considered clinical inertia. A logistic regression showed that the use of antidiabetics (odds ratio: 2.31; 95% confidence interval: 1.290-4.167; P = .008) was statistically associated with an increased risk of clinical inertia. With a determination of the frequency of inertia and the high effectiveness of antihypertensive treatment, valuable information can be provided to understand the predictors of clinical inertia.

Translational research in nephrology: chronic kidney disease prevention and public health

This narrative review evaluates translational research with respect to five important risk factors for chronic kidney disease (CKD): physical inactivity, high salt intake, smoking, diabetes and hypertension. We discuss the translational research around prevention of CKD and its complications both at the level of the general population, and at the level of those at high risk, i.e. people at increased risk for CKD or CKD complications. At the population level, all three lifestyle risk factors (physical inactivity, high salt intake and smoking) have been translated into implemented measures and clear population health improvements have been observed. At the ‘high-risk’ level, the lifestyle studies reviewed have tended to focus on the individual impact of specific interventions, and their wider implementation and impact on CKD practice are more difficult to establish. The treatment of both diabetes and hypertension appears to have improved, however the impact on CKD and CKD complications was not always clear. Future studies need to investigate the most effective translational interventions in low and middle income countries.

Hypertension control and antihypertensive therapy in patients with chronic kidney disease

BACKGROUND

Hypertension is a major risk factor in the progression of chronic kidney disease (CKD). Although hypertension is more prevalent and treated more often among CKD patients, it is less likely to be controlled. Current guidelines recommend the use of multiple antihypertensive agents to achieve optimal blood pressure (BP) control. However, BP control attained by number and type of antihypertensive therapy according to CKD stage has not been examined thoroughly.

STUDY DESIGN

Cross-sectional analysis of an electronic medical record (EMR) database.

SETTING AND PARTICIPANTS

A total of 115,608 patients with CKD (Stages 1-4) and diagnosed or treated hypertension in General Electric Centricity EMR from 1996 to 2012.

OUTCOME

BP control, based on JNC 7 guidelines, was defined as less than 130/80 mm Hg.

MEASUREMENTS

BP and antihypertensive therapy use was obtained from the EMR. The Cockcroft-Gault equation was used to calculate estimated glomerular filtration rate and classify CKD stage.

RESULTS

Overall prevalence of BP control was 24.3%. BP control varied by CKD stage and number of antihypertensive therapy. In multivariable analysis, younger age was less likely to be associated with BP control, regardless of CKD stage. Multiple antihypertensive therapy use and BP control was strongest among CKD Stage 2 (odds ratio (OR): 1.41; 95% confidence interval (CI): 1.05, 1.90). Diuretic use was less likely to be associated with BP control among CKD Stage 1 (OR: 0.71; 95% CI: 0.59, 0.87) and 2 (OR: 0.78; 95% CI: 0.72, 0.85).

LIMITATIONS

Information on antihypertensive prescription fill data and adherence to medication regimens was unavailable.

CONCLUSIONS

This study highlighted the need to pay closer attention to achieving BP treatment goals for younger individuals with CKD. More research is needed to assess the extent to which specific combinations of antihypertensive drugs leads to adequate BP control.

Achievement of therapeutic targets in patients with diabetes and chronic kidney disease: insights from the Associazione Medici Diabetologi Annals initiative

BACKGROUND

Chronic kidney disease (CKD) entails a worse cardiovascular outcome. The aim of our work was to study the relationship between CKD and the achievement of recommended targets for glycated haemoglobin (HbA1c), low-density lipoprotein cholesterol (LDL-c) and blood pressure (BP) in a real-life sample of patients with type 2 diabetes mellitus (T2DM).

METHODS

We analysed a sample of 116 777 outpatients from the Network of the Italian Association of Clinical Diabetologists; all patients had T2DM and at least one measurement of HbA1c, LDL-c, BP, serum creatinine and albuminuria in the year 2010. The outcome was the achievement of HbA1c, LDL-c and BP values as recommended by International Guidelines.

RESULTS

In the entire sample, the mean value of HbA1c was 7.2 ± 1.2%, of LDL-c was 102 ± 33 mg/dL and of BP was 138/78 ± 19/9 mmHg. CKD and its components were associated with poor glycaemic and BP control, notwithstanding greater use of glucose and BP-lowering drugs, while no association was found with LDL-c values. Factors independently related to unsatisfactory glycaemic control included female gender, body mass index, duration of disease and high albuminuria. Men, older people and those taking statins were more likely to reach LDL-c target levels. Male gender, age and high albuminuria strongly affected the achievement of BP targets.

CONCLUSIONS

CKD or its components, mainly high albuminuria, are associated with failure to reach therapeutic targets, especially for HbA1c and BP, despite a greater use of drugs in patients with T2DM.

Safety and efficacy of LCZ696, a first-in-class angiotensin receptor neprilysin inhibitor, in Japanese patients with hypertension and renal dysfunction

This 8-week, multi-center, open-label study assessed the safety and efficacy of LCZ696, a first-in-class angiotensin receptor neprilysin inhibitor, in Japanese patients with hypertension and renal dysfunction. Patients (n=32) with mean sitting systolic blood pressure (msSBP) ⩾140 mm Hg (after a 2–5-week washout of previous antihypertensive medications) and estimated glomerular filtration rate (eGFR) ⩾15 and <60 ml min⁻¹ 1.73 m⁻² received LCZ696 100 mg with an optional titration to 200 and 400 mg in a sequential manner starting from Week 2 in patients with inadequate BP control (msSBP ⩾130 mm Hg and mean sitting diastolic blood pressure (msDBP) ⩾80 mm Hg) and without safety concerns. Safety was assessed by monitoring and recording all adverse events (AEs) and change in potassium and creatinine. Efficacy was assessed as change from baseline in msSBP/msDBP. The mean baseline BP was 151.6/86.9 mm Hg, urinary albumin/creatinine ratio (UACR) geometric mean was 7.3 mg mmol⁻¹ and eGFR was ⩾30 and <60 in 25 (78.1%) patients and was ⩾15 and <30 in 7 (21.9%) patients. Fourteen (43.8%) patients reported at least one AE, which were mild in severity. No severe AEs or deaths were reported. There were no clinically meaningful changes in creatinine, potassium, blood urea nitrogen and eGFR. The geometric mean reduction in UACR was 15.1%, and the mean reduction in msSBP and msDBP was 20.5±11.3 and 8.3±6.3 mm Hg, respectively, from baseline to Week 8 end point. LCZ696 was generally safe and well tolerated and showed effective BP reduction in Japanese patients with hypertension and renal dysfunction without a decline in renal function.

Timeliness in chronic kidney disease and albuminuria identification: a retrospective cohort study

Background

Chronic kidney disease (CKD) is predominantly managed in primary care in the UK, but there is evidence of under-identification leading to lack of inclusion on practice chronic disease registers, which are necessary to ensure disease monitoring. Guidelines for CKD patients recommend urinary albumin to creatinine ratio (uACR) testing to identify albuminuria to stratify risk and guide management. This study aimed to describe the pattern and associations of timely CKD registration and uACR testing.

Methods

A retrospective cohort of individuals with incident CKD 3–5 (two estimated glomerular filtration rates (eGFR) <60 ml/min/1.73 m² ≥ three months apart) between 2007 and 2013 was identified from a linked database containing primary and secondary care data. Descriptive statistics and Cox proportional hazards models were used to identify associations with patient characteristics of timely CKD registration and uACR testing (within a year of first low eGFR).

Results

12,988 people with CKD 3–5 were identified from 88 practices and followed for median 3.3 years. During this time period, 3235 (24.9%) were CKD-registered and 4638/12,988 (35.7%) had uACR testing (median time to CKD registration 307 days and to uACR test 379 days). 1829 (14.1%) were CKD-registered and 2229 (17.2%) had uACR testing within one year. Amongst people whose CKD was registered within a year, 676/1829 (37.0%) had uACR testing within a year (vs. 1553/11,159 (13.9%) of those not registered (p < 0.001)). Timely uACR testing varied by year, with a sharp rise in proportion in 2009 (when uACR policy changed). Timely CKD registration was independently associated with lower eGFR, being female, earlier year of joining the cohort, having diabetes, hypertension, or cardiovascular disease but not with age. Timely uACR testing was associated with timely CKD registration, younger age, having diabetes, higher baseline eGFR and later year of joining the cohort.

Conclusions

Better systems are needed to support timely CKD identification, registration and uACR testing in primary care in order to facilitate risk stratification and appropriate clinical management.

Electronic supplementary material

The online version of this article (doi:10.1186/s12875-015-0235-8) contains supplementary material, which is available to authorized users.

The effects of acute kidney injury on long-term renal function and proteinuria in a general hospitalised population

BACKGROUND

Acute kidney injury (AKI) is common in hospitalised patients and is associated with adverse long-term consequences. There is an urgent need to understand these sequelae in general hospitalised patients utilising a prospective cohort-based approach. We aimed to test the feasibility of study methodology prior to commencing a large-scale study and investigate the effects of AKI on chronic kidney disease (CKD) progression and proteinuria.

METHODS

Pilot study testing novel methodology for remote patient recruitment within a prospective case-control design. 300 cases (hospitalised patients with AKI) and controls (hospitalised patients without AKI) were matched 1:1 for age and baseline estimated glomerular filtration rate (eGFR). 70% of cases had AKI stage 1, 16% AKI stage 2 and 14% AKI stage 3. Renal function and proteinuria were measured 3 and 12 months after hospital admission.

RESULTS

The study met pre-defined recruitment, withdrawal and matching criteria. Renal function was worse in the AKI group at 3 (eGFR 61 ± 20 vs. 74 ± 23 ml/min/1.73 m(2), p < 0.001) and 12 months (eGFR 64 ± 23 vs. 75 ± 25 ml/min/1.73 m(2), p < 0.001). More cases than controls had CKD progression at 3 months (14 vs. 0.7%, p < 0.001). This difference persisted to 12 months, but there was no significant change between 3 and 12 months. Proteinuria and albuminuria were more prevalent in the AKI group and associated with CKD progression.

CONCLUSIONS

We describe a method of remote patient recruitment which could be employed more widely for prospective observational studies. Even mild AKI is associated with long-term renal dysfunction. Further investigation using this methodology is now underway.

Making audit actionable: an example algorithm for blood pressure management in chronic kidney disease

Despite widespread use of clinical guidelines, actual care often falls short of ideal standards. Electronic health records (EHR) can be analyzed to provide information on how to improve care, but this is seldom done in sufficient detail to guide specific action. We developed an algorithm to provide practical, actionable information for care quality improvement using blood pressure (BP) management in chronic kidney disease (CKD) as an exemplar. We used UK clinical guidelines and EHR data from 440 patients in Salford (UK) to develop the algorithm. We then applied it to 532,409 individual patient records, identifying 11,097 CKD patients, 3,766 (34%) of which showed room for improvement in their care: either through medication optimization or better BP monitoring. Manual record reviews to evaluate accuracy indicated a positive-predictive value of 90%. Such algorithms could help improve the management of chronic conditions by providing the missing link between clinical audit and decision support.

Effective CKD care in European countries: challenges and opportunities for health policy

Chronic kidney disease (CKD) is an important global public health problem that is associated with adverse health outcomes and high health care costs. Effective and cost-effective treatments are available for slowing the progression of CKD and preventing its complications, including cardiovascular disease. Although wealthy nations have highly structured schemes in place to support the care of people with kidney failure, less consideration has been given to health systems and policy for the much larger population of people with non-dialysis-dependent CKD. Further, how to integrate such strategies with national and international initiatives for control of other chronic noncommunicable diseases (NCDs) merits attention. We synthesized the various approaches to CKD control across 17 European countries and present our findings according to the key domains suggested by the World Health Organization framework for NCD control. This report identifies opportunities to strengthen CKD-relevant health systems and explores potential mechanisms to capitalize on these opportunities. Across the 17 countries studied, we found a number of common barriers to the care of people with non-dialysis-dependent CKD: limited work force capacity, the nearly complete absence of mechanisms for disease surveillance, lack of a coordinated CKD care strategy, poor integration of CKD care with other NCD control initiatives, and low awareness of the significance of CKD. These common challenges faced by diverse health systems reflect the need for international cooperation to strengthen health systems and policies for CKD care.

Impact of baroreflex activation therapy on renal function--a pilot study

BACKGROUND/AIMS

Resistant hypertension and chronic kidney disease (CKD) are interlinked via sympathetic overdrive. Baroreflex activation therapy (BAT) has been shown to chronically reduce blood pressure (BP) in patients with resistant hypertension. The effect of BAT on renal function in CKD patients with resistant hypertension has not been reported. The aim of this study was to investigate the effect of sympathetic inhibition on renal function in CKD patients.

METHODS

23 CKD patients with resistant hypertension were prospectively treated with BAT. Analyses were performed before and 6 months after the start of BAT. The renal function was analyzed by creatinine, cystatin C, glomerular filtration rate (GFR), renin, aldosterone, fractioned and 24-hour sodium excretion and analyses of urine marker proteins. The purpose of the control group was to investigate the influence of treating patients in a center for hypertension and regression to the mean on investigated variables.

RESULTS

The office mean BP decreased from 116.9 ± 20.9 mm Hg to 104.2 ± 22.2 mm Hg (p < 0.01), while the number of prescribed antihypertensive classes decreased from 6.6 ± 1.6 to 6.1 ± 1.7 (p = 0.02). Proteinuria and albuminuria decreased from a median of 283.9 and 47.7 to 136.5 (p = 0.01) and 45.0 mg/g creatinine (p = 0.01) with pronounced effects in higher CKD stage III + IV compared to I + II (p < 0.01). CKD-EPI cystatin C equation improved from 53.6 ± 22.7 to 60.4 ± 26.1 ml/min (p = 0.02). While creatinine and GFR were impaired after a period of 6 months, no changes of proteinuria, albuminuria, or BP were obtained in control patients.

CONCLUSION

The data of this prospective trial demonstrate potential nephroprotective effects of BAT in therapy-resistant hypertension in CKD patients by a reduction of BP, proteinuria and moreover, a stabilization of estimated GFR.

Development of a formula for estimation of sodium intake from spot urine in people with chronic kidney disease

BACKGROUND/AIMS

High sodium intake is associated with adverse cardiovascular and renal outcomes in people with chronic kidney disease (CKD), and simple methods to facilitate assessment of sodium intake are required. The objective of this study was to develop a new formula to estimate 24-hour urinary sodium (24hUNa) excretion from urinary Na concentration measured on an early morning urine specimen (EM UNa).

METHODS

Seventy participants from a prospective cohort of patients with CKD stage 3 in primary care, the Renal Risk in Derby (RRID) study, agreed to collect an additional EM UNa on the day after completing a 24-hour urine collection. A formula to estimate 24hUNa from EM UNa and body weight was developed using the coefficients from a multivariable linear regression equation. The accuracy of the formula was tested by calculating the P30 (proportion of estimates within 30% of measured sodium exection), and the ability of the estimated 24hUNa to discriminate between measured sodium intake above or below 100 mmol/day was assessed by receiver operating characteristic (ROC) curve. A Bland-Altman plot was used to estimate the bias and limits of agreement between estimated and measured 24hUNa. Seventy-four additional paired 24hUNa and EM UNa from 50 CKD stage 3 patients in the RRID study were used to validate the formula.

RESULTS

The mean difference between measured and estimated 24hUNa was 2.08 mmol/day. Measured and estimated 24hUNa were significantly correlated (r = 0.55; p < 0.001) but accuracy of estimated 24hUNa was low (P30 = 60%). Analysis of the ROC curve with a cut-off point >100 mmol/day yielded an area under the curve of 0.668, sensitivity of 0.85 and specificity of 0.52.

CONCLUSIONS

We have developed a simple formula to identify people with a high sodium intake from EM UNa, suitable for use in large-cohort or population studies.

Blood pressure control is similar in treated hypertensive patients with optimal or with high-normal albuminuria

BACKGROUND

Although elevated urinary albumin excretion (UAE) is associated with cardiovascular prognosis and high blood pressure (BP), it is unknown whether differences in BP control could also exist between patients with different grades of UAE, even in the normal range. We sought to explore the association between different levels of UAE and BP control in treated hypertensive patients.

METHODS

A cohort of 1,200 treated hypertensive patients was evaluated. Clinical data, including 2 office BP measurements and UAE averaged from 2 samples, were recorded. Albuminuria was categorized into 4 groups: G0 (UAE <10mg/g), G1 (UAE 10-29 mg/g), G2 (UAE 30-299 mg/g), and G3 (UAE ≥300 mg/g).

RESULTS

Forty-three percent of patients had systolic BP ≥140 mm Hg and/or diastolic BP ≥90 mm Hg. Median UAE was significantly higher (20.3 vs. 11.7 mg/g; P < 0.001) in these patients than in controlled hypertensive patients (BP<140/90 mm Hg). When UAE was categorized into the 4 groups, there were differences in BP control among groups (P < 0.001).The proportion of noncontrolled patients in G2 (52.3%) was significantly higher than in G0 (36.8%) and G1 (41.5%) (P < 0.01 and P < 0.05, respectively). Importantly, no significant differences were observed between G0 and G1 (P = 0.18) or between G2 and G3 (P = 0.48). With G0 as the reference group, the odds ratio of lack of BP control for the G2 group after adjustment for confounders was 1.40 (95% confidence interval =1.16-1.68; P < 0.001).

CONCLUSIONS

Lack of BP control is more prevalent among patients with microalbuminuria than in patients with normoalbuminuria. No significant difference was seen between patients with optimal or high-normal UAE.

Chronic kidney disease in general populations and primary care: diagnostic and therapeutic considerations

PURPOSE OF REVIEW

The majority of people with chronic kidney disease (CKD) are managed by primary care physicians and nurses, but much of the initial research on CKD care was based in secondary care. The purpose of this article is to review the important recent studies of CKD in primary care that are starting to provide an evidence base for the strategies to improve the management and outcomes of the unreferred majority of people with CKD.

RECENT FINDINGS

People with CKD in primary care populations differ substantially from those familiar to nephrologists in secondary care by being older, having less reduction in glomerular filtration rate (GFR) and lower prevalence of proteinuria. These differences have important implications for management priorities. Detailed studies have identified widespread deficiencies in the care of patients with CKD in primary care (though these are also reported in secondary care). Interventions that may improve performance include automated reporting of estimated GFR, incentivizing primary care practitioners to achieve therapeutic goals and quality improvement strategies such as audit-based education.

SUMMARY

Studies have identified a need for improved management of CKD in primary care as well as methods to achieve this. Future studies should focus on the promotion of self-management through telemedicine and the Internet.

Spironolactone to prevent cardiovascular events in early-stage chronic kidney disease (STOP-CKD): study protocol for a randomized controlled pilot trial

BACKGROUND

Chronic kidney disease is associated with increased arterial stiffness even in the early stages and this is thought to be a key mediator in the pathophysiology of the increased cardiovascular risk associated with this condition. The use of low-dose spironolactone has previously been shown to improve arterial stiffness and reduce left ventricular mass safely in early-stage chronic kidney disease in the context of careful monitoring at a university hospital. However, the majority of patients with chronic kidney disease are managed by their general practitioners in the community. It is not known whether similar beneficial effects can be achieved safely using spironolactone in the primary care setting. The aim of this study is to determine whether low-dose spironolactone can safely lower arterial stiffness in patients with stage 3 chronic kidney disease in the primary care setting.

METHODS/DESIGN

STOP-CKD is a multicentre, prospective, randomized, double-blind, placebo-controlled pilot trial of 240 adult patients with stage 3 chronic kidney disease recruited from up to 20 general practices in South Birmingham, England. Participants will be randomly allocated using a secured web-based computer randomization system to receive either spironolactone 25 mg once daily or a matching inactive placebo for 40 weeks, followed by a wash-out period of 6 weeks. Investigators, outcome assessors, data analysts and participants will all be blinded to the treatment allocation. The primary endpoint is improved arterial stiffness, as measured by carotid-femoral pulse wave velocity between baseline and 40 weeks. The secondary endpoints are incidence of hyperkalaemia, change in estimated glomerular filtration rate, change in urine albumin:creatinine ratio, change in brachial blood pressure, change in pulse waveform characteristics and overall tolerability of spironolactone. An additional quality control study, aiming to compare the laboratory serum potassium results of samples processed via two methods (utilizing routine transport or centrifugation on site before rapid transport to the laboratory) for 100 participants and a qualitative research study exploring patients' and general practitioners' attitudes to research and the use of spironolactone in chronic kidney disease in the community setting will be embedded in this pilot study.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN80658312.