The relationship of ethnicity to the prevalence and management of hypertension and associated chronic kidney disease

Association of parity with the prevalence of hypertension in Japan: The Tohoku Medical Megabank Community-based cohort study

This study investigated the association of parity with hypertension prevalence in Japanese women while considering a clinical history of hypertensive disorders of pregnancy (HDP) and menopausal status. This cross-sectional study included 30,530 Japanese women (6700 premenopausal; 23 830 postmenopausal). The association between parity and the prevalence of hypertension was evaluated using a multiple logistic regression model with possible confounders. In premenopausal women, no statistically significant association between parity and hypertension prevalence was found. When not adjusted for current body mass index (BMI), a linear graded association was observed between parity and the prevalence of hypertension in postmenopausal women. However, the association between parity and hypertension prevalence in postmenopausal women was attenuated after adjustment for current BMI. Both current BMI and a clinical history of HDP were significantly associated with a high risk of hypertension in both premenopausal and postmenopausal women. Our results also suggest that continuous surveillance and preventive measures for hypertension should be provided for women with HDP and high parity.

Hypertension prevalence, coding and control in an urban primary care setting in the UK between 2014 and 2021

OBJECTIVE

Hypertension is a leading preventable cause of mortality, yet high rates of undiagnosed and uncontrolled hypertension continue. The burden falls most heavily on some ethnic minorities and the socially deprived, with the COVID-19 pandemic having further widened inequalities. We sought to determine the prevalence and predictors of unmeasured blood pressure (BP), uncoded elevated BP and uncontrolled hypertension in primary care across 2014-2021.

METHODS

A population-based cohort study using data from all 41 general practices in a socioeconomically diverse inner-city borough. BP measurements, sociodemographic, lifestyle and clinical factors were extracted from anonymized primary care data. Hypertension and BP control were defined using NICE guidelines. Associations between patient characteristics and hypertension outcomes were identified using logistical regression modelling.

RESULTS

Of 549 082 patients, 39.5% had unmeasured BP; predictors included male sex [AOR 2.40, 95% confidence interval (95% CI) 2.26-2.43] and registration in the pandemic years. Of 71 970 adults with elevated BP, 36.0% were uncoded; predictors included obesity (AOR 2.51, 95% CI 2.42-2.60) and increasing age. Of 44 648 adults on the hypertension register, 46.8% had uncontrolled hypertension; predictors included black ethnicity compared to white (AOR 1.54, 95% CI 1.41-1.68) and cardiovascular co-morbidities (AOR 1.23, 95% CI 1.21-1.25). Social deprivation was only weakly or not significantly associated with hypertension outcomes.

CONCLUSION

The burden of uncoded elevated BP and uncontrolled hypertension is high. Obesity and male sex were associated with uncoded elevated BP and uncontrolled hypertension. Black ethnicity was associated with uncontrolled hypertension. Initiatives are needed to optimize hypertension coding and control, with an emphasis on specific population subgroups.

Inequities in kidney health and kidney care

Health inequity refers to the existence of unnecessary and unfair differences in the ability of an individual or community to achieve optimal health and access appropriate care. Kidney diseases, including acute kidney injury and chronic kidney disease, are the epitome of health inequity. Kidney disease risk and outcomes are strongly associated with inequities that occur across the entire clinical course of disease. Insufficient investment across the spectrum of kidney health and kidney care is a fundamental source of inequity. In addition, social and structural inequities, including inequities in access to primary health care, education and preventative strategies, are major risk factors for, and contribute to, poorer outcomes for individuals living with kidney diseases. Access to affordable kidney care is also highly inequitable, resulting in financial hardship and catastrophic health expenditure for the most vulnerable. Solutions to these injustices require leadership and political will. The nephrology community has an important role in advocacy and in identifying and implementing solutions to dismantle inequities that affect kidney health.

Kidney Function and Long-Term Risk of End-Stage Kidney Disease and Mortality in a Multiethnic Population

Introduction

Contemporary differences between South Asian and White ethnicities in the incidence of end-stage kidney disease (ESKD) and mortality are poorly described.

Methods

Data for all South Asian patients who had an estimated glomerular filtration rate (eGFR) measure after January 1, 2006, and 1 million randomly selected participants of other ethnicities were extracted from the Clinical Practice Research Datalink (CPRD). All participants were followed-up with from index date until ESKD, all-cause mortality, or end of study. All-cause mortality rate and ESKD incidence rate by age were described among Whites and South Asians, and adjusted hazard ratios (HRs) of these 2 outcomes by baseline eGFR estimated using Cox proportional hazard model.

Results

A total of 40,888 South Asians and 236,634 Whites were followed for a median of 5.3 and 9.4 years for ESKD incidence and mortality outcomes, respectively. All-cause mortality rates were higher among Whites than South Asians; South Asian women aged between 70 and 85 years had a slightly higher ESKD incidence rate compared to their White counterparts. Compared to Whites with a baseline eGFR of 90 ml/min per 1.73 m2, adjusted HRs for all-cause mortality were significantly lower among South Asians than Whites; however, adjusted HRs for ESKD incidence by baseline eGFR were similar in both ethnicities. Calculating South Asian eGFRs using an ethnicity-specific equation had no impact on the results.

Conclusions

South Asians experience lower mortality than Whites but not substantially higher rates of ESKD. Further research is warranted to better understand the reasons for these ethnic differences and possible impacts on chronic kidney disease (CKD) service delivery and patient outcomes.

Ethnic differences in kidney function in childhood: the Born in Bradford Cohort Renal Study

Background: Endstage kidney failure rates are higher in South Asians than in White Europeans. Low birth weight is associated with adult chronic kidney disease and is more common in South Asians. Foetal kidney size was smaller in South Asians in the Born in Bradford (BiB) birth cohort. As part of BiB follow up, we aimed to investigate if there were ethnic differences in kidney function and blood pressure in early childhood and whether this was different by foetal kidney size. Methods: Serum creatinine, cystatin C, urea, and urinary albumin to creatinine ratio (ACR), protein to creatinine ratio (PCR) and retinol binding protein (RBP) were analysed in blood and urine samples from those who participated in the BiB follow-up at 7-11 years. Ethnicity was categorised by parental self-report as White European and South Asian. Estimated glomerular filtration rate (eGFR) was calculated using Schwartz, and cystatin C Zappitelli and Filler equations. Linear regression was used to examine the association between ethnicity and eGFR, PCR and blood pressure. Results: 1591 children provided blood (n=1403) or urine (n=625) samples. Mean eGFR was 92 ml/min/1.73m 2 (standard deviation (SD) 9) using Schwartz (n=1156) and 94 (SD 11) using Zappitelli (n=1257). CKD prevalence was rare (1 with eGFR <60 ml/min/1.73m 2, 14 (2.4%) had raised ACR (>2.5 mg/mmol in boys/3.5 mg/mmol in girls). Diastolic blood pressure was higher in South Asian children (difference 2.04 mmHg, 95% CI 0.99 to 3.10) but was not significant in adjusted analysis. There was no evidence of association in adjusted models between ethnicity and any eGFR or urinary measure at this age. Conclusions: There was no evidence of significant ethnic differences in kidney function at pre-pubertal age despite differences in kidney volume at birth. Longitudinal follow-up is required to track ethnic patterns in kidney function and blood pressure as children develop through puberty.

Ethnic differences in hypertension management, medication use and blood pressure control in UK primary care, 2006-2019: a retrospective cohort study

Background

In the UK, previous work suggests ethnic inequalities in hypertension management. We studied ethnic differences in hypertension management and their contribution to blood pressure (BP) control.

Methods

We conducted a cohort study of antihypertensive-naïve individuals of European, South Asian and African/African Caribbean ethnicity with a new raised BP reading in UK primary care from 2006 to 2019, using the Clinical Practice Research Datalink (CPRD). We studied differences in: BP re-measurement after an initial hypertensive BP, antihypertensive initiation, BP monitoring, antihypertensive intensification, antihypertensive persistence/adherence and BP control one year after antihypertensive initiation. Models adjusted for socio-demographics, BP, comorbidity, healthcare usage and polypharmacy (plus antihypertensive class, BP monitoring, intensification, persistence and adherence for BP control models).

Findings

A total of 731,506 (93.5%), 30,379 (3.9%) and 20,256 (2.6%) people of European, South Asian and African/African Caribbean ethnicity were studied. Hypertension management indicators were similar or more favourable for South Asian than European groups (OR/HR [95% CI] in fully-adjusted models of BP re-measurement: 1.16 [1.09, 1.24]), antihypertensive initiation: 1.49 [1.37, 1.62], BP monitoring: 0.97 [0.94, 1.00] and antihypertensive intensification: 1.10 [1.04, 1.16]). For people of African/African Caribbean ethnicity, BP re-measurement rates were similar to those of European ethnicity (0.98 [0.91, 1.05]), and antihypertensive initiation rates greater (1.48 [1.32, 1.66]), but BP monitoring (0.91 [0.87, 0.95]) and intensification rates lower (0.93 [0.87, 1.00]). Persistence and adherence were lower in South Asian (0.48 [0.45, 0.51] and 0.51 [0.47, 0.56]) and African/African Caribbean (0.38 [0.35, 0.42] and 0.39 [0.36, 0.43]) than European groups. BP control was similar in South Asian and less likely in African/African Caribbean than European groups (0.98 [0.90, 1.06] and 0.81 [0.74, 0.89] in age, gender and BP adjusted models). The latter difference attenuated after adjustment for persistence (0.91 [0.82, 0.99]) or adherence (0.92 [0.83, 1.01]), and was absent for antihypertensive-adherent people (0.99 [0.88, 1.10]).

Interpretation

We demonstrate that antihypertensive initiation does not vary by ethnicity, but subsequent BP control was notably lower among people of African/African Caribbean ethnicity, potentially associated with being less likely to remain on regular treatment. A nationwide strategy to understand and address differences in ongoing management of people on antihypertensives is imperative.

Funding

Diabetes UK.

Risk Amplifiers for Vascular Disease and CKD in South Asians: When Intrinsic β-Cell Dysfunction Meets a High-Carbohydrate Diet

South Asians, comprising almost one fourth of the world population, are at higher risk of type 2 diabetes mellitus, hypertension, cardiovascular disease, and CKD compared with other ethnic groups. This has major public health implications in South Asia and in other parts of the world to where South Asians have immigrated. The interplay of various modifiable and nonmodifiable risk factors confers this risk. Traditional models of cardiometabolic disease progression and CKD evaluation may not be applicable in this population with a unique genetic predisposition and phenotype. A wider understanding of dietary and lifestyle influences, genetic and metabolic risk factors, and the pitfalls of conventional equations estimating kidney function in this population are required in providing care for kidney diseases. Targeted screening of this population for metabolic and vascular risk factors and individualized management plan for disease management may be necessary. Addressing unhealthy dietary patterns, promoting physical activity, and medication management that adheres to cultural factors are crucial steps to mitigate the risk of cardiovascular disease and CKD in this population. In South Asian countries, a large rural and urban community-based multipronged approach using polypills and community health workers to decrease the incidence of these diseases may be cost-effective.

Trans-ethnic Mendelian-randomization study reveals causal relationships between cardiometabolic factors and chronic kidney disease

BACKGROUND

This study was to systematically test whether previously reported risk factors for chronic kidney disease (CKD) are causally related to CKD in European and East Asian ancestries using Mendelian randomization.

METHODS

A total of 45 risk factors with genetic data in European ancestry and 17 risk factors in East Asian participants were identified as exposures from PubMed. We defined the CKD by clinical diagnosis or by estimated glomerular filtration rate of <60 ml/min/1.73 m2. Ultimately, 51 672 CKD cases and 958 102 controls of European ancestry from CKDGen, UK Biobank and HUNT, and 13 093 CKD cases and 238 118 controls of East Asian ancestry from Biobank Japan, China Kadoorie Biobank and Japan-Kidney-Biobank/ToMMo were included.

RESULTS

Eight risk factors showed reliable evidence of causal effects on CKD in Europeans, including genetically predicted body mass index (BMI), hypertension, systolic blood pressure, high-density lipoprotein cholesterol, apolipoprotein A-I, lipoprotein(a), type 2 diabetes (T2D) and nephrolithiasis. In East Asians, BMI, T2D and nephrolithiasis showed evidence of causality on CKD. In two independent replication analyses, we observed that increased hypertension risk showed reliable evidence of a causal effect on increasing CKD risk in Europeans but in contrast showed a null effect in East Asians. Although liability to T2D showed consistent effects on CKD, the effects of glycaemic phenotypes on CKD were weak. Non-linear Mendelian randomization indicated a threshold relationship between genetically predicted BMI and CKD, with increased risk at BMI of >25 kg/m2.

CONCLUSIONS

Eight cardiometabolic risk factors showed causal effects on CKD in Europeans and three of them showed causality in East Asians, providing insights into the design of future interventions to reduce the burden of CKD.

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.

Association Between Renal Dysfunction and Low HDL Cholesterol Among the Elderly in China

Objective: Chronic kidney disease (CKD) and cardiovascular disease (CVD) have a high morbidity and mortality among the elderly. Low levels of high-density lipoprotein cholesterol (HDL-C), a traditional risk marker for CVD, are common in CKD patients. Little is known about the association of low HDL-C with renal dysfunction in the community dwelling population. Methods: This was a population-based cross-sectional study included 4,753 participants enrolled in a prospective study, the Shanghai Elderly Cardiovascular Health (SHECH) study. Estimated glomerular filtration rate (eGFR), calculated by the Chinese Modification of Diet in Renal Disease (C-MDRD equation), was used to assess renal dysfunction. Associations between renal dysfunction and low HDL-C were evaluated using multiple logistic regression models and restricted cubic splines. Results: Of 4,649 individuals who met inclusion criteria, 620 (13.34%) had low HDL-C at <40 mg/dl. In the fully adjusted model, lower eGFR of <60 ml/min/1.73 m² (OR, 2.03; 95% CI, 1.21-3.43) and marginal eGFR of 60 to 90 ml/min/1.73 m² (OR, 1.26; 95% CI, 1.01-1.58) were significantly associated with low HDL-C, compared with normal eGFR of ≥90 ml/min/1.73 m². Moreover, consistent findings were obtained in subsidiary analyses using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Fully adjusted cubic spline models indicated a significant dose-response relationship between eGFR and low HDL-C (P for non-linearity, 0.356). Conclusion: In this general elderly population, renal dysfunction was independently and significantly associated with low HDL-C, and the prevalence of low HDL-C increased with decreasing eGFR, such that even slight changes in renal function may be associated with altered lipid levels.

Uncoded chronic kidney disease in primary care: a cross-sectional study of inequalities and cardiovascular disease risk management

BACKGROUND

Uncoded chronic kidney disease (CKD) is associated with poorer quality of care.

AIM

To ascertain the proportion and determinants of CKD, which have not been formally recorded (Read coded), and identify differences in management and quality-of-care measures for patients with coded and uncoded CKD.

DESIGN AND SETTING

Cross-sectional survey undertaken in an ethnically diverse adult population using primary care electronic health records (EHRs) from GP clinics in Lambeth, South London, UK.

METHOD

Multivariable logistic regression analysis examined the association of demographic factors, selected comorbidities, deprivation, and cardiovascular disease risk management in CKD, with coding status as outcome.

RESULTS

In total, the survey involved 286 162 adults, of whom 9325 (3.3%) were identified with CKD stage 3-5 (assigned as CKD based on estimated glomerular filtration rate [eGFR] values). Of those identified with CKD, 4239 (45.5%) were Read coded, and 5086 (54.5%) were uncoded. Of those identified with CKD stage 3-5, individuals aged ≥50 years were more likely to be coded for CKD, compared with those aged <50 years. Lower levels of coding were independently associated with deprivation and black Caribbean, black African, South Asian, and non-stated ethnicities, compared with white ethnicity. Prescribed statin and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker medications were associated with increased odds of coded CKD.

CONCLUSION

This study found that >50% of CKD was uncoded and, for those patients, quality of care was lower compared with those with coded CKD. Future research and practices should focus on areas of greater deprivation and targeted initiatives for those aged <50 years and of black African, black Caribbean, South Asian, or non-stated ethnic groups. Possible areas for improvement include diagnostic coding support, automated CKD recording, and clinical decision support (based on adjusted eGFR results) in the GP clinical records.

Ethnic minority disparities in progression and mortality of pre-dialysis chronic kidney disease: a systematic scoping review

Background

There are a growing number of studies on ethnic differences in progression and mortality for pre-dialysis chronic kidney disease (CKD), but this literature has yet to be synthesised, particularly for studies on mortality.

Methods

This scoping review synthesized existing literature on ethnic differences in progression and mortality for adults with pre-dialysis CKD, explored factors contributing to these differences, and identified gaps in the literature. A comprehensive search strategy using search terms for ethnicity and CKD was taken to identify potentially relevant studies. Nine databases were searched from 1992 to June 2017, with an updated search in February 2020.

Results

8059 articles were identified and screened. Fifty-five studies (2 systematic review, 7 non-systematic reviews, and 46 individual studies) were included in this review. Most were US studies and compared African-American/Afro-Caribbean and Caucasian populations, and fewer studies assessed outcomes for Hispanics and Asians. Most studies reported higher risk of CKD progression in Afro-Caribbean/African-Americans, Hispanics, and Asians, lower risk of mortality for Asians, and mixed findings on risk of mortality for Afro-Caribbean/African-Americans and Hispanics, compared to Caucasians. Biological factors such as hypertension, diabetes, and cardiovascular disease contributed to increased risk of progression for ethnic minorities but did not increase risk of mortality in these groups.

Conclusions

Higher rates of renal replacement therapy among ethnic minorities may be partly due to increased risk of progression and reduced mortality in these groups. The review identifies gaps in the literature and highlights a need for a more structured approach by researchers that would allow higher confidence in single studies and better harmonization of data across studies to advance our understanding of CKD progression and mortality.

Prevalence of chronic kidney disease in the community using data from OxRen: a UK population-based cohort study

Background

Chronic kidney disease (CKD) is a largely asymptomatic condition of diminished renal function, which may not be detected until advanced stages without screening.

Aim

To establish undiagnosed and overall CKD prevalence using a cross-sectional analysis.

Design and setting

Longitudinal cohort study in UK primary care.

Method

Participants aged ≥60 years were invited to attend CKD screening visits to determine whether they had reduced renal function (estimated glomerular filtration rate [eGFR] <60 ml/min/1.73 m² or albumin:creatinine ratio ≥3 mg/mmol). Those with existing CKD, low eGFR, evidence of albuminuria, or two positive screening tests attended a baseline assessment (CKD cohort).

Results

A total of 3207 participants were recruited and 861 attended the baseline assessment. The CKD cohort consisted of 327 people with existing CKD, 257 people with CKD diagnosed through screening (CKD prevalence of 18.2%, 95% confidence interval [CI] = 16.9 to 19.6), and 277 with borderline/transient decreased renal function. In the CKD cohort, 54.4% were female, mean standard deviation (SD) age was 74.0 (SD 6.9) years, and mean eGFR was 58.0 (SD 18.4) ml/min/1.73 m². Of the 584 with confirmed CKD, 44.0% were diagnosed through screening. Over half of the CKD cohort (51.9%, 447/861) fell into CKD stages 3–5 at their baseline assessment, giving an overall prevalence of CKD stages 3–5 of 13.9% (95% CI = 12.8 to 15.1). More people had reduced eGFR using the Modification of Diet in Renal Disease (MDRD) equation than with CKD Epidemiology Collaboration (CKD-EPI) equation in the 60–75-year age group and more had reduced eGFR using CKD-EPI in the ≥80-year age group.

Conclusion

This study found that around 44.0% of people living with CKD are undiagnosed without screening, and prevalence of CKD stages 1–5 was 18.2% in participants aged >60 years. Follow-up will provide data on annual incidence, rate of CKD progression, determinants of rapid progression, and predictors of cardiovascular events.

How do primary care doctors in England and Wales code and manage people with chronic kidney disease? Results from the National Chronic Kidney Disease Audit

Background

In the UK, primary care records are electronic and require doctors to ascribe disease codes to direct care plans and facilitate safe prescribing. We investigated factors associated with coding of chronic kidney disease (CKD) in patients with reduced kidney function and the impact this has on patient management.

Methods

We identified patients meeting biochemical criteria for CKD (two estimated glomerular filtration rates <60 mL/min/1.73 m² taken >90 days apart) from 1039 general practitioner (GP) practices in a UK audit. Clustered logistic regression was used to identify factors associated with coding for CKD and improvement in coding as a result of the audit process. We investigated the relationship between coding and five interventions recommended for CKD: achieving blood pressure targets, proteinuria testing, statin prescription and flu and pneumococcal vaccination.

Results

Of 256 000 patients with biochemical CKD, 30% did not have a GP CKD code. Males, older patients, those with more severe CKD, diabetes or hypertension or those prescribed statins were more likely to have a CKD code. Among those with continued biochemical CKD following audit, these same characteristics increased the odds of improved coding. Patients without any kidney diagnosis were less likely to receive optimal care than those coded for CKD [e.g. odds ratio for meeting blood pressure target 0.78 (95% confidence interval 0.76–0.79)].

Conclusion

Older age, male sex, diabetes and hypertension are associated with coding for those with biochemical CKD. CKD coding is associated with receiving key primary care interventions recommended for CKD. Increased efforts to incentivize CKD coding may improve outcomes for CKD patients.

Improving coding and primary care management for patients with chronic kidney disease: an observational controlled study in East London

BACKGROUND

The UK national chronic kidney disease (CKD) audit in primary care shows diagnostic coding in the electronic health record for CKD averages 70%, with wide practice variation. Coding is associated with improvements to risk factor management; CKD cases coded in primary care have lower rates of unplanned hospital admission.

AIM

To increase diagnostic coding of CKD (stages 3-5) and primary care management, including blood pressure to target and prescription of statins to reduce cardiovascular disease risk.

DESIGN AND SETTING

Controlled, cross-sectional study in four East London clinical commissioning groups (CCGs).

METHOD

Interventions to improve coding formed part of a larger system change to the delivery of renal services in both primary and secondary care in East London. Quarterly anonymised data on CKD coding, blood pressure values, and statin prescriptions were extracted from practice computer systems for 1-year pre- and post-initiation of the intervention.

RESULTS

Three intervention CCGs showed significant coding improvement over a 1 year period following the intervention (regression for post-intervention trend P<0.001). The CCG with highest coding rates increased from 76-90% of CKD cases coded; the lowest coding CCG increased from 52-81%. The comparison CCG showed no change in coding rates. Combined data from all practices in the intervention CCGs showed a significant increase in the proportion of cases with blood pressure achieving target levels (difference in proportion P<0.001) over the 2-year study period. Differences in statin prescribing were not significant.

CONCLUSION

Clinically important improvements to coding and management of CKD in primary care can be achieved by quality improvement interventions that use shared data to track and monitor change supported by practice-based facilitation. Alignment of clinical and CCG priorities and the provision of clinical targets, financial incentives, and educational resource were additional important elements of the intervention.

New perspectives on the role of melatonin in human sleep, circadian rhythms and their regulation

In mammals, a central circadian clock, located in the suprachiasmatic nuclei (SCN) of the hypothalamus, tunes the innate circadian physiological rhythms to the ambient 24 h light-dark cycle to invigorate and optimize the internal temporal order. The SCN-activated, light-inhibited production of melatonin conveys the message of darkness to the clock and induces night-state physiological functions, for example, sleep/wake blood pressure and metabolism. Clinically meaningful effects of melatonin treatment have been demonstrated in placebo-controlled trials in humans, particularly in disorders associated with diminished or misaligned melatonin rhythms, for example, circadian rhythm-related sleep disorders, jet lag and shift work, insomnia in children with neurodevelopmental disorders, poor (non-restorative) sleep quality, non-dipping nocturnal blood pressure (nocturnal hypertension) and Alzheimer's disease (AD). The diminished production of melatonin at the very early stages of AD, the role of melatonin in the restorative value of sleep (perceived sleep quality) and its sleep-anticipating effects resulting in attenuated activation of certain brain networks are gaining a new perspective as the role of poor sleep quality in the build-up of β amyloid, particularly in the precuneus, is unravelled. As a result of the recently discovered relationship between circadian clock, sleep and neurodegeneration, new prospects of using melatonin for early intervention, to promote healthy physical and mental ageing, are of prime interest in view of the emerging link to the aetiology of Alzheimer's disease. LINKED ARTICLES: This article is part of a themed section on Recent Developments in Research of Melatonin and its Potential Therapeutic Applications. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.16/issuetoc.

Atherosclerotic Cardiovascular Disease in South Asians in the United States: Epidemiology, Risk Factors, and Treatments: A Scientific Statement From the American Heart Association

South Asians (from Bangladesh, Bhutan, India, the Maldives, Nepal, Pakistan, and Sri Lanka) make up one quarter of the world's population and are one of the fastest-growing ethnic groups in the United States. Although native South Asians share genetic and cultural risk factors with South Asians abroad, South Asians in the United States can differ in socioeconomic status, education, healthcare behaviors, attitudes, and health insurance, which can affect their risk and the treatment and outcomes of atherosclerotic cardiovascular disease (ASCVD). South Asians have higher proportional mortality rates from ASCVD compared with other Asian groups and non-Hispanic whites, in contrast to the finding that Asian Americans (Asian Indian, Chinese, Filipino, Japanese, Korean, and Vietnamese) aggregated as a group are at lower risk of ASCVD, largely because of the lower risk observed in East Asian populations. Literature relevant to South Asian populations regarding demographics and risk factors, health behaviors, and interventions, including physical activity, diet, medications, and community strategies, is summarized. The evidence to date is that the biology of ASCVD is complex but is no different in South Asians than in any other racial/ethnic group. A majority of the risk in South Asians can be explained by the increased prevalence of known risk factors, especially those related to insulin resistance, and no unique risk factors in this population have been found. This scientific statement focuses on how ASCVD risk factors affect the South Asian population in order to make recommendations for clinical strategies to reduce disease and for directions for future research to reduce ASCVD in this population.

The risk factors of 9-year follow-up on hypertension in middle-aged people in Tujia-Nationality settlement of China

The aim of this study was to investigate the risk factors of hypertension in middle-aged people within the Tujia-Nationality settlement in China. Demographics questionnaires and fitness tests were performed to identify the risk factors of hypertension in middle-aged people in the years 2005, 2010 and 2014 in the area of southwest Hubei of China. Of the 2428 participants, 568 were classified as hypertensive, giving an overall occurrence of hypertension at 23.4%, and the prevalence of hypertension was the highest in the year 2014 (34.9%). Furthermore, Tujia minority had a significantly higher risk for having hypertension (odds ratio=1.055 with 95% confidence interval (CI): 1.039-1.072; P=0.001) than Han people. Individuals with the lowest level of cardiorespiratory fitness (CRF) had a 2.483-fold risk for hypertension (95% CI, 1.530-4.031; P=0.001). Obesity and overweight individuals increased the risk by 3.470-fold and 2.124-fold, respectively, for having hypertension compared to normal weight people. Finally, white-collar workers had a 58.1 and 31.8% higher risk for hypertension than blue-collar workers in rural and urban areas, respectively. These results demonstrated that the prevalence of hypertension was higher between 2011 and 2014 in the area. The main risk factors for developing hypertension were found to be sex (as woman), Tujia minority, white-collar workers, overweight-obese, those with a middle school education, and those with the lowest CRF.

Baseline General Characteristics of the Korean Chronic Kidney Disease: Report from the KoreaN Cohort Study for Outcomes in Patients With Chronic Kidney Disease (KNOW-CKD)

The KoreaN Cohort Study for Outcomes in Patients With Chronic Kidney Disease (KNOW-CKD) was developed to investigate various clinical courses and risk factors for progression of Korean chronic kidney disease (CKD). The KNOW-CKD study consists of nine clinical centers in Korea, and patients aged between 20 and 75 years with CKD from stage 1 to 5 (predialysis) were recruited. At baseline, blood and urine samples were obtained and demographic data including comorbidities, drugs, quality of life, and health behaviors were collected. Estimated glomerular filtration rate (eGFR) was calculated by 4-variable Modification of Diet in Renal Disease (MDRD) equation using isotope dilution mass spectrometry (IDMS)-calibrated serum creatinine measured at a central laboratory. As a dynamic cohort, a total of 2,341 patients were enrolled during the enrollment period from 2011 until 2015, among whom 2,238 subjects were finally analyzed for baseline profiles. The mean age of the cohort was 53.7 ± 12.2 year and 61.2% were men. Mean eGFR was 50.5 ± 30.3 mL/min/1.73 m². The participants with lower eGFR had a tendency to be older, with more comorbidities, to have higher systolic blood pressure (BP) and pulse pressure, with lower income level and education attainment. The patients categorized as glomerulonephritis (GN) were 36.2% followed by diabetic nephropathy (DN, 23.2%), hypertensive nephropathy (HTN, 18.3%), polycystic kidney disease (PKD, 16.3%), and other unclassified disease (6.1%). The KNOW-CKD participants will be longitudinally followed for 10 years. The study will provide better understanding for physicians regarding clinical outcomes, especially renal and cardiovascular outcomes in CKD patients.

Evaluating ethnic differences in the prescription of NSAIDs for chronic kidney disease: a cross-sectional survey of patients in general practice

BACKGROUND

The public health burden of chronic kidney disease (CKD) and end-stage kidney disease is a national priority and is the subject of recent guidelines. In the UK, ethnic minority groups are over-represented in the renal replacement population (17.8%) compared with the white population (11%).

AIM

Non-steroidal anti-inflammatory drugs (NSAIDs) are a preventable cause of renal damage. Previous studies suggest a prescribing prevalence between 9% and 36% among those with CKD, but have not examined differences by ethnic group.

DESIGN AND SETTING

Cross-sectional survey of 12 011 patients with identified CKD (stages 3-5) in the three PCTs of Tower Hamlets, Hackney, and Newham.

METHOD

Assessment of NSAID prescribing rates in a multi-ethnic, socially-deprived population, using descriptive and multivariate analysis.

RESULTS

NSAIDs were prescribed for 11.1% of patients with CKD in the year prior to November 2012. Prescribing rates decreased stepwise by stage of renal impairment. Using daily defined dosages this study shows that in comparison with white groups both South Asian and black groups are much less likely to be in the top decile of NSAID prescribing, hence the overall prescribing load will be less: (odds ratio [OR] for South Asians = 0.34, 95% confidence interval [CI] = 0.22 to 0.54, OR for black groups = 0.34, 95% CI = 0.19 to 0.63).

CONCLUSION

National rates of NSAID prescribing continue to rise, and over-the-counter sales remain unmonitored, despite longstanding concerns about renal outcomes. Prescribing patterns indicate that GPs reduce prescribing as CKD progresses. Differential use of NSAIDs by ethnic group is unlikely to contribute to the high rates of end-stage kidney disease in ethnic minority groups.

A peer outreach initiative to increase the registration of minorities as organ donors

Background

Black, Asian and minority ethnic (BAME) communities are disproportionately affected by inequalities in transplant services in the UK. There are some indications from pilot programmes that appeals for BAME organ donors may be more effectively communicated by employing grassroots, community-networking approaches, but such initiatives have not been adequately described or evaluated.

Methods

Lay individuals from BAME communities were trained as peer outreach workers. They attended a series of public events to promote knowledge of organ donation and transplantation among the public. Information was gathered from 806 evaluation forms completed by event attendees at 34 separate events. From these, 54 follow-up interviews were conducted with event attendees who completed evaluation forms, indicated that they intended to sign up to the NHS Organ Donor Register (ODR) within the next month and consented to follow-up.

Results

Peer outreach initiatives of the type evaluated are associated with increased numbers of BAME people registering as organ donors. A total of 8.8% of event attendees signed up to the NHS ODR. The programme was most effective with people who had previously considered becoming organ donors but who did not know how to go about it. It was less effective with people who had not previously considered it, or who were scared about signing up, or who feared family or religious disapproval.

Conclusions

Peer outreach programmes with BAME communities can be an effective way of reducing inequalities by increasing the number of people on the NHS ODR and encouraging people to think about the issue.

Smaller kidney size at birth in South Asians: findings from the Born in Bradford birth cohort study

BACKGROUND

Rates of advanced chronic kidney disease and renal replacement therapy are higher in South Asian than in white British populations. Low birth weight is also more frequent in South Asian populations and has been associated with increased risks of kidney disease, perhaps due to a reduced nephron endowment.

METHODS

Using ultrasound scans at 34 weeks of gestation, we measured fetal kidney dimensions (transverse and anteroposterior diameters, length and circumference) and derived volume in a random sample of 872 white British and 715 South Asian participants in the Born in Bradford cohort study. Kidney measurements were compared between ethnic groups.

RESULTS

Birth weight for gestational age at 40 weeks was 200 g less in South Asian babies compared with white British babies. The mean kidney volume for gestational age was 16% lower in South Asian than in white British babies [8.79 versus 10.45 cm(3), difference 1.66 cm(3) (95% confidence interval 1.40-1.93, P < 0.001)]. The difference was robust after adjustment for maternal age, socio-economic factors, marital status, body mass index, smoking and alcohol use in pregnancy, parity, baby's gender and birth weight for gestational age [adjusted difference 1.38 cm(3) (0.97-1.84), P < 0.001]. There were smaller reductions in other fetal measures.

CONCLUSION

South Asian babies have smaller kidneys compared with white British babies, even after adjusting for potential confounders including birth weight. This finding may contribute to increased risks of adult kidney disease in South Asian populations.

Modelling, evaluating and implementing cost-effective services to reduce the impact of stroke

Background

Stroke is a leading cause of death and disability but there is little information on the longer-term needs of patients and those of different ethnic groups.

Objectives

To estimate risk of stroke, longer-term needs and outcomes, risk of recurrence, trends and predictors of effective care, to model cost-effective configurations of care, to understand stakeholders’ perspectives of services and to develop proposals to underpin policy.

Design

Population-based stroke register, univariate and multivariate analyses, Markov and discrete event simulation, and qualitative methods for stakeholder perspectives of care and outcome.

Setting

South London, UK, with modelling for estimates of cost-effectiveness.

Participants

Inner-city population of 271,817 with first stroke in lifetime between 1995 and 2012.

Outcome measures

Stroke incidence rates and trends, recurrence, survival, activities of daily living, anxiety, depression, quality of life, appropriateness and cost-effectiveness of care, and qualitative narratives of perspectives.

Data sources

South London Stroke Register (SLSR), qualitative data, group discussions.

Results

Stroke incidence has decreased since 1995, particularly in the white population, but with a higher stroke risk in black groups. There are variations in risk factors and types of stroke between ethnic groups and a large number of strokes occurred in people with untreated risk factors with no improvement in detection observed over time. A total of 30% of survivors have a poor range of outcomes up to 10 years after stroke with differences in outcomes by sociodemographic group. Depression affects over half of all stroke patients and the prevalence of cognitive impairment remains 22%. Survival has improved significantly, particularly in the older black groups, and the cumulative risk of recurrence at 10 years is 24.5%. The proportion of patients receiving effective acute stroke care has significantly improved, yet inequalities of provision remain. Using register data, the National Audit Office (NAO) compared the levels of stroke care in the UK in 2010 with previous provision levels and demonstrated that improvements have been cost-effective. The treatment of, and productivity loss arising from, stroke results in total societal costs of £8.9B a year and 5% of UK NHS costs. Stroke unit care followed by early supported discharge is a cost-effective strategy, with the main gain being years of life saved. Half of stroke survivors report unmet long-term needs. Needs change over time, but may not be stroke specific. Analysis of patient journeys suggests that provision of care is also influenced by structural, social and personal characteristics.

Conclusions/recommendations

The SLSR has been a platform for a range of health services research activities of international relevance. The programme has produced data to inform policy and practice with estimates of need for stroke prevention and care services, identification of persistent sociodemographic inequalities in risk and care despite a reduction in stroke risk, quantification of the effectiveness and cost-effectiveness of care and development of models to simulate configurations of care. Stroke is a long-term condition with significant social impact and the data on need and economic modelling have been utilised by the Department of Health, the NAO and Healthcare for London to assess need and model cost-effective options for stroke care. Novel approaches are now required to ensure that such information is used effectively to improve population and patient outcomes.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme and the Department of Health via the National Institute for Health Research Biomedical Research Centre award to Guy’s and St Thomas’ NHS Foundation Trust in partnership with King’s College London.

Are there enough GPs in England to detect hypertension and maintain access? A cross-sectional study

BACKGROUND

Fewer patients are recorded by practices as having hypertension than are identified in systematic population surveys. However, as more patients are recorded on practice hypertension registers, mortality from coronary heart disease and stroke declines.

AIM

To determine whether the number of GPs per 1000 practice population is associated with the number of patients recorded by practices as having hypertension, and whether patients' reports of being able to get an appointment with a GP are associated with the number of GPs and the number of patients recorded as having hypertension.

DESIGN AND SETTING

Cross-sectional study of available data for all general practices in England for 2008 to 2009.

METHOD

A model was developed to describe the hypothesised relationships between population (deprivation, ethnicity, age, poor health) and practice characteristics (list size, number of GPs per 1000 patients, management of hypertension) and the number of patients with hypertension and patient-reported ability to get an appointment fairly quickly. Two regression analyses were undertaken.

RESULTS

Practices recorded only 13.3% of patients as having hypertension. Deprivation, age, poor health, white ethnicity, hypertension management, and the number of GPs per 1000 patients predicted the number of patients recorded with hypertension. Being able to get an appointment fairly quickly was associated with the number of patients recorded with hypertension, age, deprivation, practice list size, and the number of GPs per 1000 patients.

CONCLUSION

In order to improve detection of hypertension as part of a strategy to lower mortality from coronary heart disease, the capacity of practices to detect hypertension while maintaining access needs to be improved. Increasing the supply of GPs may be necessary, as well as improvements in efficiency.

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

BACKGROUND

Poorly controlled hypertension is independently associated with mortality, cardiovascular risk and disease progression in chronic kidney disease (CKD). In the UK, CKD stage 3 is principally managed in primary care, including blood pressure (BP) management. Controlling BP is key to improving outcomes in CKD. This study aimed to investigate associations of BP control in people with CKD stage 3.

METHODS

1,741 patients with CKD 3 recruited from 32 general practices for the Renal Risk in Derby Study underwent medical history, clinical assessment and biochemistry testing. BP control was assessed by three standards: National Institute for Health and Clinical Excellence (NICE), National Kidney Foundation Kidney Disease Outcome Quality Initiative (KDOQI) and Kidney Disease: Improving Global Outcomes (KDIGO) guidelines. Descriptive statistics were used to compare characteristics of people achieving and not achieving BP control. Univariate and multivariate logistic regression was used to identify factors associated with BP control.

RESULTS

The prevalence of hypertension was 88%. Among people with hypertension, 829/1426 (58.1%) achieved NICE BP targets, 512/1426 (35.9%) KDOQI targets and 859/1426 (60.2%) KDIGO targets. Smaller proportions of people with diabetes and/or albuminuria achieved hypertension targets. 615/1426 (43.1%) were only taking one antihypertensive agent. On multivariable analysis, BP control (NICE and KDIGO) was negatively associated with age (NICE odds ratio (OR) 0.27; 95% confidence interval (95% CI) 0.17-0.43) 70-79 compared to <60), diabetes (OR 0.32; 95% CI 0.25-0.43)), and albuminuria (OR 0.56; 95% CI 0.42-0.74)). For the KDOQI target, there was also association with males (OR 0.76; 95% CI 0.60-0.96)) but not diabetes (target not diabetes specific). Older people were less likely to achieve systolic targets (NICE target OR 0.17 (95% CI 0.09,0.32) p < 0.001) and more likely to achieve diastolic targets (OR 2.35 (95% CI 1.11,4.96) p < 0.001) for people >80 compared to < 60).

CONCLUSIONS

Suboptimal BP control was common in CKD patients with hypertension in this study, particularly those at highest risk of adverse outcomes due to diabetes and or albuminuria. This study suggests there is scope for improving BP control in people with CKD by using more antihypertensive agents in combination while considering issues of adherence and potential side effects.

Trends in risk factor prevalence and management before first stroke: data from the South London Stroke Register 1995-2011

BACKGROUND AND PURPOSE

Vascular risk factors are suboptimally managed internationally. This study investigated time trends in risk factors diagnosed before stroke and their treatment, and factors associated with appropriate medication use.

METHODS

A total of 4416 patients with a first stroke were registered in the population-based South London Stroke Register from 1995 to 2011. Previously diagnosed risk factors and usual medications were collected from patients' primary care and hospital records. Trends and associations were assessed using multivariate logistic regression.

RESULTS

Seventy-two percent of patients were diagnosed previously with 1 or more risk factors; 30% had diagnosed risk factors that were untreated. Hypercholesterolemia increased significantly during the study period; myocardial infarction and transient ischemic attack prevalences decreased. Antiplatelet prescription increased in atrial fibrillation (AF), myocardial infarction, and transient ischemic attack (AF, 37%-51%, P<0.001; myocardial infarction, 48%-69%, P<0.001; transient ischemic attack, 49%-61%, P=0.015). Anticoagulant prescription for AF showed a nonsignificant increase (12%-23%; P=0.059). Fewer older patients with AF were prescribed anticoagulants (age, >85 versus <65 years; adjusted relative risk, 0.19; 95% confidence interval, 0.08-0.41). Black ethnicity (adjusted relative risk, 1.17; 95% confidence interval, 1.10-1.23) and female sex (adjusted relative risk, 1.09; 95% confidence interval, 1.03-1.15) were associated with increased antihypertensive drug prescription; other medications did not vary by ethnicity or sex.

CONCLUSIONS

Antiplatelet and cholesterol-lowering treatment prescribing have improved significantly over time; however, only a minority with AF received anticoagulants, and this did not improve significantly. Overall, 30% of strokes occurred in patients with previously diagnosed but untreated risk factors.

Effect of add-on direct renin inhibitor aliskiren in patients with non-diabetes related chronic kidney disease

Background

The renin-angiotensin-aldosterone system (RAAS) plays an important role in the progression of chronic kidney disease (CKD). Although dual RAAS inhibition results in worse renal outcomes than monotherapy in high risk type 2 diabetes patients, the effect of dual RAAS inhibition in patients with non-DM CKD is unclear. The aim of this study was to evaluate the potential renoprotective effect of add-on direct renin inhibitor in non-DM CKD patients.

Methods

We retrospectively enrolled 189 non-DM CKD patients who had been taking angiotensin II receptor blockers (ARBs) for more than six months. Patients were divided into an add-on aliskiren group and an ARB monotherapy group. The primary outcomes were a decline in glomerular filtration rate (GFR) and a reduction in urinary protein-to-creatinine ratio at six months.

Results

The baseline characteristics of the two groups were similar. Aliskiren 150 mg daily reduced the urinary protein-to-creatinine ratio by 26% (95% confidence interval, 15 to 37%; p < 0.001). The decline in GFR was smaller in the add-on aliskiren group (−2.1 vs. -4.0 ml/min, p = 0.038). Add-on aliskiren had a neutral effect on serum potassium in the non-DM CKD patients. In subgroup analysis, the proteinuria-reducing effect of aliskiren was more prominent in patients with a GFR less than 60 ml/min, and in patients with a urinary protein-to-creatinine ratio greater than 1.8. The effect of aliskiren in retarding the decline in GFR was more prominent in patients with hypertensive nephropathy than in those with glomerulonephritis.

Conclusion

Add-on direct renin inhibitor aliskiren (150 mg daily) safely reduced proteinuria and attenuated the decline in GFR in the non-DM CKD patients who were receiving ARBs.