Association between urinary albumin excretion and coronary heart disease in black vs white adults

Normoalbuminuria-is it normal? The association of urinary albumin within the 'normoalbuminuric' range with adverse cardiovascular and mortality outcomes: A systematic review and meta-analysis

AIM

To assess the association between urinary albumin-to-creatinine ratio (UACR) categories within the normal range with mortality and adverse cardiovascular outcomes.

MATERIALS AND METHODS

PubMed and Embase were systematically searched for real-world evidence studies. Studies were manually evaluated according to predefined eligibility criteria. We included prospective and retrospective cohort studies of the association between UACR categories <30 mg/g and cardiovascular outcomes or mortality. Published information regarding study design, participants, UACR categorization, statistical methods, and results was manually collected. Two UACR categorization approaches were defined: a two-category (UACR <10 mg/g vs. 10-30 mg/g) and a three-category division (UACR <5 mg/g vs. 5-10 and 10-30 mg/g). A random effects meta-analysis was performed on studies eligible for the meta-analysis.

RESULTS

In total, 22 manuscripts were identified for the systematic review, 15 of which were eligible for the meta-analysis. The results suggest an association between elevated UACR within the normal to mildly increased range and higher risks of all-cause mortality, cardiovascular death, and coronary heart disease, particularly in the range of 10-30 mg/g. Compared with UACR <10 mg/g, the hazard ratio [HR (95% confidence interval, CI)] for UACR between 10 and 30 mg/g was 1.41 (1.15, 1.74) for all-cause mortality and 1.56 (1.23, 1.98) for coronary heart disease. Compared with UACR <5 mg/g, the risk of cardiovascular mortality for UACR between 10 and 30 mg/g was more than twofold [HR (95% CI): 2.12 (1.61, 2.80)]. Intermediate UACR (5-10 mg/g) was also associated with a higher risk of all-cause mortality [HR (95% CI): 1.14 (1.05, 1.24)] and cardiovascular mortality [HR (95% CI): 1.50 (1.14, 1.99)].

CONCLUSIONS

We propose considering higher UACR within the normoalbuminuric range as a prognostic factor for cardiovascular morbidity and mortality. Our findings underscore the clinical significance of even mild increases in albuminuria.

Sex and Race Differences in Obesity-Related Genetic Susceptibility and Risk of Cardiometabolic Disease in Older US Adults

Importance

The fat mass and obesity-associated gene (FTO) is associated with obesity phenotypes, but the association is inconsistent across populations. Within-population differences may explain some of the variability observed.

Objective

To investigate sex differences in the association between FTO single-nucleotide variants (SNVs) and obesity traits among self-identified non-Hispanic Black and non-Hispanic White US adults, to examine whether the SNVs were associated with cardiometabolic diseases, and to evaluate whether obesity mediated the association between FTO SNVs and cardiometabolic diseases.

Design, Setting, and Participants

This cross-sectional study used data from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, a US population-based cohort study with available genetic data (assayed in 2018) and phenotypic data at baseline (enrolled 2003-2007). Participants were aged 45 to 98 years at baseline. Data were analyzed from October 2021 to October 2022.

Exposures

Eleven SNVs in the FTO gene present among both Black and White participants.

Main Outcomes and Measures

Objectively measured obesity indicators (body mass index and waist-to-height ratio), objectively measured and/or self-reported cardiometabolic diseases (hypertension, stroke history, heart disease, and diabetes), and self-reported social-economic and psychosocial status.

Results

A total of 10 447 participants (mean [SD] age, 64.4 [9.7] years; 5276 [55.8%] women; 8743 [83.7%] Black and 1704 [16.3%] White) were included. In the White group, 11 FTO SNVs were significantly associated with obesity, hypertension, and diabetes using linear models (eg, body mass index: β = 0.536; 95% CI, 0.197-0.875), but none of the FTO SNVs were associated with obesity traits in the Black group. White males had a higher risk of obesity while White females had a higher risk of hypertension and diabetes. However, 1 FTO SNV (rs1121980) was associated with a direct increase in the risk of heart disease in Black participants not mediated by obesity (c' = 0.145 [SE, 0.0517]; P = .01).

Conclusions and Relevance

In this cross-sectional study of obesity phenotypes and their association with cardiometabolic diseases, the tested FTO SNVs reflected sex differences in White participants. Different patterns of associations were observed among self-identified Black participants. Therefore, these results could inform future work discovering risk alleles or risk scores unique to Black individuals or further investigating genetic risk in all US residents.

Associations Between Albuminuria and Mortality Among US Adults by Demographic and Comorbidity Factors

Background Albuminuria is a known marker of mortality risk. Whether the association between albuminuria and mortality differs by demographic and comorbidity factors remains unclear. Therefore, we sought to determine whether albuminuria is differentially associated with mortality. Methods and Results This study included 49 640 participants from the National Health and Nutrition Examination Survey (1999-2018). All-cause mortality through 2019 was linked from the National Death Index. Multivariable-adjusted Poisson regression models were used to determine whether levels of urine albumin-to-creatinine ratio (ACR) were associated with mortality. Models were adjusted for demographic, socioeconomic, behavioral, and clinical factors. Mean age in the population was 46 years, with 51.3% female, and 30.3% with an ACR ≥10 mg/g. Over a median follow-up of 9.5 years, 6813 deaths occurred. Compared with ACR <10, ACR ≥300 was associated with increased risk of mortality by 132% overall (95% CI, 2.01-2.68), 124% among men (95% CI, 1.84-2.73), 158% among women (95% CI, 2.14-3.11), 130% among non-Hispanic White adults (95% CI: 1.89-2.79), 135% among non-Hispanic Black adults (95% CI, 1.82-3.04), and 114% among Hispanic adults (95% CI, 1.55-2.94). Compared with ACR <10, ACR ≥300 was associated with increased risk of mortality by 148% among individuals with neither hypertension nor hypercholesterolemia (95% CI, 1.69-3.64), 128% among individuals with hypertension alone (95% CI, 1.86-2.79), and 166% among individuals with both hypertension and hypercholesterolemia (95% CI, 2.18-3.26). Conclusions We found strong associations between albuminuria and mortality risk, even at mildly increased levels of albuminuria. Associations persisted across categories of sex, race or ethnicity, and comorbid conditions, with subtle differences.

Interrelations between albuminuria, electrocardiographic left atrial abnormality, and incident atrial fibrillation in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort

BACKGROUND

The objective of the study was to examine the joint associations of albuminuria and electrocardiographic left atrial abnormality (ECG-LAA) with incident atrial fibrillation (AF) and whether this relationship varies by race.

METHODS

This analysis included 6670 participants free of clinical cardiovascular disease (CVD), including atrial fibrillation (AF), from the Multi-Ethnic Study of Atherosclerosis. ECG-LAA was defined as P-wave terminal force in V1 [PTFV1] >5000 μV × ms. Albuminuria was defined as urine albumin-creatinine ratio (UACR) ≥30 mg/g. Incident AF events through 2015 were ascertained from hospital discharge records and study-scheduled electrocardiograms. Cox proportional hazard models were used to examine the association of "no albuminuria + no ECG-LAA (reference)", "isolated albuminuria", "isolated ECG-LAA" and "albuminuria + ECG-LAA" with incident AF.

RESULTS

Over a median follow-up of 13.8 years, 979 incident cases of AF occurred. In adjusted models, the concomitant presence of ECG-LAA and albuminuria was associated with a higher risk of AF than either ECG-LAA or albuminuria in isolation (HR (95% CI): 2.43 (1.65-3.58), 1.33 (1.05-1.69), and 1.55 (1.27-1.88), respectively (interaction p-value = 0.50). Effect modification by race was observed with a 4-fold greater AF risk in Black participants with albuminuria + ECG-LAA (HR (95%CI): 4.37 (2.38-8.01) but no significant association in White participants (HR (95% CI) 0.60 (0.19-1.92) respectively; (interaction p-value for race x albuminuria-ECG-LAA combination = 0.05).

CONCLUSIONS

Concomitant presence of ECG-LAA and albuminuria confers a higher risk of AF compared to either one in isolation with a stronger association in Blacks than Whites.

Microalbuminuria during acute coronary syndrome: Association with 22-year mortality and causes of death. The ABC-8* study on heart disease. (*ABC is an acronym for Adria, Bassano, Conegliano, and Padova Hospitals)

BACKGROUND

Microalbuminuria is associated with adverse outcomes in acute coronary syndrome (ACS) patients.

METHODS

To evaluate the very long-term association between Microalbuminuria and the overall mortality and causes of death in this clinical setting, we prospectively studied 579 unselected ACS patients admitted to three hospitals. The baseline albumin-to-creatinine ratio (ACR) was measured on days 1, 3, and 7 in 24-h urine samples. Patients were followed for 22 years or until death.

RESULTS

Virtually all patients completed follow-up; 449(78%) had died: 41% due to non-sudden cardiac death (non-SCD), 19% sudden cardiac death (SCD), 40% due to non-cardiac (non-CD) death. Using unadjusted Cox regression analysis, ACR was a significant predictor of all-cause mortality (hazard ratio [HR] 1.26;95%confidence interval [CI] 1.22-1.31; p˂0.0001) and the three causes of death (HR 1.40;95%CI 1.32-1.48; p˂0.0001), (HR 1.22;95%CI 1.12-1.32; p˂0.0001) and (HR 1.16;95%CI 1.09-1.23; p˂0.0001) for non-SCD, SCD and non-CD respectively. Using a fully adjusted model, ACR was a significant independent predictor of all-cause mortality (HR 1.12; 95%CI 1.08-1.16; p˂0.0001) and only non-SCD (HR 1.21; 95%CI 1.14-1.29; p˂0.0001). There was a positive interaction between ACR level and history of AMI (HR 1.15; 95%CI 1.03-1.29; p = 0.01) and the presence of heart failure at admission (HR 1.11; 95%CI 1.01-1.24; p = 0.04), and negative interaction with higher than median LVEF (HR 0.89; 95%CI 0.80-0.99; p = 0.03) for all-cause mortality at the multivariable level.

CONCLUSION

Based on the present analysis, baseline urinary albumin excretion during ACS is a strong independent predictor of the very long-term mortality risk, chiefly due to non-sudden cardiac death.

The Potential of Albuminuria as a Biomarker of Diabetic Complications

Diabetes mellitus is a disease of dysregulated blood glucose homeostasis. The current pandemic of diabetes is a significant driver of patient morbidity and mortality, as well as a major challenge to healthcare systems worldwide. The global increase in the incidence of diabetes has prompted researchers to focus on the different pathogenic processes responsible for type 1 and type 2 diabetes. Similarly, increased morbidity due to diabetic complications has accelerated research to uncover pathological changes causing these secondary complications. Albuminuria, or protein in the urine, is a well-recognised biomarker and risk factor for renal and cardiovascular disease. Albuminuria is a mediator of pathological abnormalities in diabetes-associated conditions such as nephropathy and atherosclerosis. Clinical screening and diagnosis of diabetic nephropathy is chiefly based on the presence of albuminuria. Given the ease in measuring albuminuria, the potential of using albuminuria as a biomarker of cardiovascular diseases is gaining widespread interest. To assess the benefits of albuminuria as a biomarker, it is important to understand the association between albuminuria and cardiovascular disease. This review examines our current understanding of the pathophysiological mechanisms involved in both forms of diabetes, with specific focus on the link between albuminuria and specific vascular complications of diabetes.

Association of Urine Albumin Excretion With Incident Heart Failure Hospitalization in Community-Dwelling Adults

OBJECTIVES

This study examined the association between urinary albumin excretion and incident heart failure (HF) hospitalization.

BACKGROUND

Excess urinary albumin excretion is more strongly associated with incident stroke and coronary heart disease risk in black than in white individuals. Whether similar associations extend to HF is unclear.

METHODS

This study examined the associations between the urinary albumin-to-creatinine ratio (ACR) and incident hospitalization for HF overall in 24,433 REGARDS (Reasons for Geographic and Racial Differences in Stroke) study participants free of suspected HF at baseline; findings were stratified by race and HF subtype (preserved vs. reduced ejection fraction). Models were adjusted for sociodemographic, clinical, and laboratory variables including estimated glomerular filtration rate, and multiple imputation was used to account for missing covariate data.

RESULTS

After a median follow-up of 9.2 years, 881 incident HF events (332 preserved ejection fraction, 447 reduced ejection fraction, 102 unspecified) were observed. Compared to the lowest ACR category (<10 mg/g), the risk of incident HF increased with increasing ACR categories (10 to 29 mg/g hazard ratio [HR]: 1.49; 95% confidence interval [CI]: 1.26 to 1.78; 30 to 300 mg/g HR: 2.32; 95% CI: 1.93 to 2.78; >300 mg/g HR: 4.42; 95% CI: 3.36 to 5.83) in the fully adjusted model. Results did not differ by race. The magnitude of the association between ACR and HF with preserved ejection fraction was greater than with HF with reduced ejection fraction (HR comparing highest vs. lowest ACR category: 6.20; 95% CI: 4.15 to 9.26 vs. HR: 4.37; 95% CI: 3.00 to 6.25, respectively; p = 0.05).

CONCLUSIONS

Higher ACR was associated with greater risk of incident HF hospitalization in community-dwelling black and white adults.

Risk factors for 'microsize' vs. usual myocardial infarctions in the REasons for Geographic and Racial Differences in Stroke (REGARDS) study

AIMS

A recently described phenomenon is that of myocardial infarction (MI) events that meet criteria for MI, but that have very low peak troponin elevations, so-called 'microsize MI'. These events are very common and associated with increased risk of all-cause mortality. Our aim is to compare risk factors for microsize MI vs. usual MI events.

METHODS AND RESULTS

Among 24 470 participants of the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort free of coronary heart disease at baseline, heart-related hospitalizations were expert adjudicated for MI using published guidelines. Myocardial infarctions were classified as microsize MI (peak troponin <0.5 ng/mL) or usual MI (peak troponin ≥0.5 ng/mL). Competing risk analyses assessed associations between baseline risk factors and incident microsize vs. usual MI. Between 2003 and 2013 there were 891 MIs; 279 were microsize MI and 612 were usual MI. Risk factors for both usual MI and microsize MI include age, gender, diabetes, and urinary albumin to creatinine ratio. Risk factors for only usual MI include Residence in the Stroke Belt and Buckle regions and current smoking. Black race was associated with a uniquely lower risk of usual MI.

CONCLUSION

The similarities in risk profiles suggest a possible common aetiology and should encourage clinicians to both treat reversible risk factors for microsize MI and to initiate secondary prevention strategies following these events until this emerging clinical entity is better understood. Future studies should further assess the clinical outcomes of these two entities and their effect on future management.

Crescents formations are independently associated with higher mortality in biopsy-confirmed immunoglobulin A nephropathy

BACKGROUND AND OBJECTIVES

Immunoglobulin A Nephropathy (IgAN) is the most common type of glomerulonephritis with variable renal outcome. The association between IgAN and patient survival is limited. The effect of crescents on patient survival was never studied.

MATERIALS

We conducted a retrospective cohort study between January 2003 and December 2013. All patients with the biopsy-proved IgAN was enrolled for the analysis of patient survival and renal survival. Cox regression model was used analyze the associated factors for patient survival.

RESULTS

All 388 participants with IgAN were enrolled, in which 45 patients with crescents. The mean percentage of glomeruli involvement was 23±18.9%. After long-term follow-up, crescents group had both worse renal (p = 0.034) and patient survivals (p = 0.016). In univariate Cox regression model, the age (HR = 1.08, 95% CI = 1.05-1.12, p<0.001), crescents (HR = 3.93, 95% CI = 1.18-13.07, p = 0.025), serum albumin (HR = 0.023, 95%CI = 0.11-0.50, p<0.001), blood total protein (HR = 0.46, 95%CI = 0.28-0.75, p = 0.002), HDL (HR = 0.95, 95%CI = 0.91-0.99, p = 0.009), daily urine protein (HR = 1.14, 95%CI = 1.01-1.29, p = 0.038), urine PCR (HR = 1.07, 95%CI = 1.02-1.12, p = 0.003), serum IgM (HR = 0.98, 95%CI = 0.96-1.00, p = 0.036), BUN (HR = 1.02, 95%CI = 1.01-1.02, p = 0.005), and eGFR (HR = 0.097, 95%CI = 0.94-0.99, p = 0.0011) were associated with patient survival. After multivariate Cox regression analysis, age (HR = 1.08, 95%CI = 1.01-1.13, p = 0.013), crescents (HR = 5.57, 95%CI = 1.14-29.05, p = 0.034), and HDL (HR = 0.94, 95%CI = 0.90-0.99, p = 0.026) were associated with patient survival. Crescents IgAN is with the highest risk (up to 5.75 of HR) for patient mortality.

CONCLUSIONS

The major strengths of the present study is that crescents IgAN had worse patient survival compared to non-crescents IgAN. Clinicians should be more careful to care patients with crescents IgAN.

Association of Urine Albumin/Creatinine Ratio below 30 mg/g and Left Ventricular Hypertrophy in Patients with Type 2 Diabetes

Several studies show that even a level of urine albumin/creatinine ratio (UACR) within the normal range (below 30 mg/g) increases the risk of cardiovascular diseases. We speculate that mildly increased UACR is related to left ventricular hypertrophy (LVH) in patients with type 2 diabetes mellitus (T2DM). In this retrospective study, 317 patients with diabetes with normal UACR, of whom 62 had LVH, were included. The associations between UACR and laboratory indicators, as well as LVH, were examined using multivariate linear regression and logistic regression, respectively. The diagnostic efficiency and the optimal cutoff point of UACR for LVH were evaluated using the area under the receiver operating characteristic curve (AUC) and Youden index. Our results showed that patients with LVH had significantly higher UACR than those without LVH (P < 0.001). The prevalence of LVH presented an upward trend with the elevation of UACR. UACR was independently and positively associated with hemoglobin A1c (P < 0.001). UACR can differentiate LVH (AUC = 0.682, 95% CI (0.602–0.760), P < 0.001). The optimal cutoff point determined with the Youden index was UACR = 10.2 mg/g. When categorized by this cutoff point, the odds ratio (OR) for LVH in patients in the higher UACR group (10.2–30 mg/g) was 3.104 (95% CI: 1.557–6.188, P=0.001) compared with patients in the lower UACR group (<10.2 mg/g). When UACR was analyzed as a continuous variable, every double of increased UACR, the OR for LVH was 1.511 (95% CI: 1.047–2.180, P=0.028). Overall, UACR below 30 mg/g is associated with LVH in patients with T2DM. The optimal cutoff value of UACR for identifying LVH in diabetes is 10 mg/g.

Normality data of eGFR and validity of commonly used screening tests for CKD in an area with endemic CKD of unknown etiology; need for age and sex based precise cutoff values

BACKGROUND

Chronic Kidney Disease in certain part of Sri Lanka and increasing burden of CKD in some other countries is a global public health problem. While the underlying causes of majority of cases are unknown, effective control and prevention strategies are yet to be taken. Though the disease has been identify more than decade ago, baseline data on renal function are not available. This study reports the age and sex disaggregated data of renal functions among screening participants of the Anuradhapura, the district with the highest disease burden in Sri Lanka.

METHODS

The screening prorgramme was done as a part of CKD control programme of Anuradhapura. All screening centers were visited and information and urine sample collection tubes were distributed before the screening date. A serum and urine sample was taken from all participants. In a subsample, urine sulfosalicylic acid test (SSA Test), urine dipstick test, urine albumin to creatinine ratio (UACR) and urine protein to creatinine ratio (UPCR) was done.

RESULTS

The study sample included 7768 apparently healthy people aging 18 to 93 years and females (n = 5522) accounted for 71.1% of the sample. Mean age of the participants was 45.9 (SD 14.1) years. Mean eGFR in this population was 90.8 mL/min/1.73m2(SD 24.6) with a significantly lower eGFR (88.1 mL/min/1.73m2) among males compared to female (92.8 mL/min/1.73m2). Mean eGFR was 115 mL/min/1.73m2 (SE .5) among participants aging less than 30 and this value drastically reduced to 59.1 mL/min/1.73m2 (SE 1.2) among people aging more than 70 years. Proportion of people having reduction of eGFR compatible with mild, moderate, severe and kidney failure categories was 33.9(32.7-34.8), 8.4(7.8-9.0), 1.5(1.2-1.7) and 0.7(0.5-0.9). The age and sex adjusted prevalence of eGFR less than 60 mL/min/1.73 m2 in a single sample in this population was 10.6%. Bayesian Latent Class model analysis shows that UPCR> 150 has the highest sensitivity to detect those who are with eGFR less than 60 mL/min/1.73 m2. UACR, the usual recommended test as a screening test was having a sensitivity of 35.3% in this population.

CONCLUSION

UPCR and UACR should be use as a screening tests in areas with high proportion of CKDu patients. More research are required to investigate the use of age and sex specific cut off values to diagnose CKD.

Normality data of eGFR and validity of commonly used screening tests for CKD in an area with endemic CKD of unknown etiology; need for age and sex based precise cutoff values

BACKGROUND

Chronic Kidney Disease in certain part of Sri Lanka and increasing burden of CKD in some other countries is a global public health problem. While the underlying causes of majority of cases are unknown, effective control and prevention strategies are yet to be taken. Though the disease has been identify more than decade ago, baseline data on renal function are not available. This study reports the age and sex disaggregated data of renal functions among screening participants of the Anuradhapura, the district with the highest disease burden in Sri Lanka.

METHODS

The screening prorgramme was done as a part of CKD control programme of Anuradhapura. All screening centers were visited and information and urine sample collection tubes were distributed before the screening date. A serum and urine sample was taken from all participants. In a subsample, urine sulfosalicylic acid test (SSA Test), urine dipstick test, urine albumin to creatinine ratio (UACR) and urine protein to creatinine ratio (UPCR) was done.

RESULTS

The study sample included 7768 apparently healthy people aging 18 to 93 years and females (n = 5522) accounted for 71.1% of the sample. Mean age of the participants was 45.9 (SD 14.1) years. Mean eGFR in this population was 90.8 mL/min/1.73m²(SD 24.6) with a significantly lower eGFR (88.1 mL/min/1.73m²) among males compared to female (92.8 mL/min/1.73m²). Mean eGFR was 115 mL/min/1.73m² (SE .5) among participants aging less than 30 and this value drastically reduced to 59.1 mL/min/1.73m² (SE 1.2) among people aging more than 70 years. Proportion of people having reduction of eGFR compatible with mild, moderate, severe and kidney failure categories was 33.9(32.7-34.8), 8.4(7.8-9.0), 1.5(1.2-1.7) and 0.7(0.5-0.9). The age and sex adjusted prevalence of eGFR less than 60 mL/min/1.73 m2 in a single sample in this population was 10.6%. Bayesian Latent Class model analysis shows that UPCR> 150 has the highest sensitivity to detect those who are with eGFR less than 60 mL/min/1.73 m2. UACR, the usual recommended test as a screening test was having a sensitivity of 35.3% in this population.

CONCLUSION

UPCR and UACR should be use as a screening tests in areas with high proportion of CKDu patients. More research are required to investigate the use of age and sex specific cut off values to diagnose CKD.

Relationship of mildly increased albuminuria and coronary artery revascularization outcomes in patients with diabetes

BACKGROUND

The aim of this study was to examine the relationship of albuminuria to cardiovascular disease outcomes in diabetic patients undergoing treatment for stable coronary artery disease.

METHODS AND RESULTS

We analyzed data from 2176 participants of the Bypass Angioplasty Revascularization Investigation in type-2 diabetes (BARI-2D) trial, a randomized clinical trial comparing Percutaneous coronary intervention/Coronary artery bypass grafting (PCI/CABG) to medical therapy for people with diabetes. The population was stratified by baseline spot urine albumin-creatinine ratio (uACR) into normal (uACR <10 mg/g), mildly (uACR ≥10 mg/g < 30 mg/g), moderately (uACR ≥30 mg/g < 300 mg/g) and severely increased (uACR ≥300 mg/g) groups, and outcomes compared between groups. Death, myocardial infarction (MI) and/or stroke were experienced by 489 patients at a mean follow-up of 4.3 ± 1.5 years. Compared with normal uACR, mildly increased uACR was associated with a 1.4 times (P = 0.042) increase in all-cause mortality. Additionally, nonwhites with type-II diabetes and stable coronary artery disease who had mildly increased albuminuria had a Hazard ratio (HR) of 3.3 times (P = 0.028) for cardiovascular death, 3.1 times for (P = 0.002) all-cause mortality, and two times for (P = 0.015) MI during follow-up.

CONCLUSIONS

Mildly increased albuminuria is a significant predictor of all-cause mortality in those with type-II diabetes mellitus and stable coronary artery disease, as well as for cardiovascular events those who are nonwhites.

Differences in Risk of Sudden Cardiac Death Between Blacks and Whites

BACKGROUND

Prior studies have consistently demonstrated that blacks have an approximate 2-fold higher incidence of sudden cardiac death (SCD) than whites; however, these analyses have lacked individual-level sociodemographic, medical comorbidity, and behavioral health data.

OBJECTIVES

The purpose of this study was to evaluate whether racial differences in SCD incidence are attributable to differences in the prevalence of risk factors or rather to underlying susceptibility to fatal arrhythmias.

METHODS

The Reasons for Geographic and Racial Differences in Stroke study is a prospective, population-based cohort of adults from across the United States. Associations between race and SCD defined per National Heart, Lung, and Blood Institute criteria were assessed.

RESULTS

Among 22,507 participants (9,416 blacks and 13,091 whites) without a history of clinical cardiovascular disease, there were 174 SCD events (67 whites and 107 blacks) over a median follow-up of 6.1 years (interquartile range: 4.6 to 7.3 years). The age-adjusted SCD incidence rate (per 1,000 person-years) was higher in blacks (1.8; 95% confidence interval [CI]: 1.4 to 2.2) compared with whites (0.7; 95% CI: 0.6 to 0.9), with an unadjusted hazard ratio of 2.35; 95% CI: 1.74 to 3.20. The association of black race with SCD risk remained significant after adjustment for sociodemographics, comorbidities, behavioral measures of health, intervening cardiovascular events, and competing risks of non-SCD mortality (hazard ratio: 1.97; 95% CI: 1.39 to 2.77).

CONCLUSIONS

In a large biracial population of adults without a history of cardiovascular disease, SCD rates were significantly higher in blacks as compared with whites. These racial differences were not fully explained by demographics, adverse socioeconomic measures, cardiovascular risk factors, and behavioral measures of health.

Risk Factors for Future Scleroderma Renal Crisis at Systemic Sclerosis Diagnosis

OBJECTIVE

Systemic sclerosis (SSc) is a disease of autoimmunity, fibrosis, and vasculopathy. Scleroderma renal crisis (SRC) is one of the most severe complications. Corticosteroid exposure, presence of anti-RNA polymerase III antibodies (ARA), skin thickness, and significant tendon friction rubs are among the known risk factors at SSc diagnosis for developing future SRC. Identification of additional clinical characteristics and laboratory findings could expand and improve the risk profile for future SRC at SSc diagnosis.

METHODS

In this retrospective cohort study of the entire military electronic medical record between 2005 and 2016, we compared the demographics, clinical characteristics, and laboratory results at SSc diagnosis for 31 cases who developed SRC after SSc diagnosis to 322 SSc without SRC disease controls.

RESULTS

After adjustment for potential confounding variables, at SSc diagnosis these conditions were all associated with future SRC: proteinuria (p < 0.001; OR 183, 95% CI 19.1-1750), anemia (p = 0.001; OR 9.9, 95% CI 2.7-36.2), hypertension (p < 0.001; OR 13.1, 95% CI 4.7-36.6), chronic kidney disease (p = 0.008; OR 20.7, 95% CI 2.2-190.7), elevated erythrocyte sedimentation rate (p < 0.001; OR 14.3, 95% CI 4.8-43.0), thrombocytopenia (p = 0.03; OR 7.0, 95% CI 1.2-42.7), hypothyroidism (p = 0.01; OR 2.8, 95% CI 1.2-6.7), Anti-Ro antibody seropositivity (p = 0.003; OR 3.9, 95% CI 1.6-9.8), and ARA (p = 0.02; OR 4.1, 95% CI 1.2-13.8). Three or more of these risk factors present at SSc diagnosis was sensitive (77%) and highly specific (97%) for future SRC. No SSc without SRC disease controls had ≥ 4 risk factors.

CONCLUSION

In this SSc cohort, we present a panel of risk factors for future SRC. These patients may benefit from close observation of blood pressure, proteinuria, and estimated glomerular filtration rate, for earlier SRC identification and intervention. Future prospective therapeutic studies could focus specifically on this high-risk population.

Association of functional and structural social support with medication adherence among individuals treated for coronary heart disease risk factors: Findings from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study

Background

Functional social support has a stronger association with medical treatment adherence than structural social support in several populations and disease conditions. Using a contemporary U.S. population of adults treated with medications for coronary heart disease (CHD) risk factors, the association between social support and medication adherence was examined.

Methods

We included 17,113 black and white men and women with CHD or CHD risk factors aged ≥45 years recruited 2003–2007 from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study. Participants reported their perceived social support (structural social support: being partnered, number of close friends, number of close relatives, and number of other adults in household; functional social support: having a caregiver in case of sickness or disability; combination of structural and functional social support: number of close friends or relatives seen at least monthly). Medication adherence was assessed using a 4-item scale. Multi-variable adjusted Poisson regression models were used to calculate prevalence ratios (PR) for the association between social support and medication adherence.

Results

Prevalence of medication adherence was 68.9%. Participants who saw >10 close friends or relatives at least monthly had higher prevalence of medication adherence (PR = 1.06; 95% CI: 1.00, 1.11) than those who saw ≤3 per month. Having a caregiver in case of sickness or disability, being partnered, number of close friends, number of close relatives, and number of other adults in household were not associated with medication adherence after adjusting for covariates.

Conclusions

Seeing multiple friends and relatives was associated with better medication adherence among individuals with CHD risk factors. Increasing social support with combined structural and functional components may help support medication adherence.

Effect of amlodipine, efonidipine, and trichlormethiazide on home blood pressure and upper-normal microalbuminuria assessed by casual spot urine test in essential hypertensive patients

The aim of this study was to assess the effects of irbesartan alone and combined with amlodipine, efonidipine, or trichlormethiazide on blood pressure (BP) and urinary albumin (UA) excretion in hypertensive patients with microalbuminuria (30≤UA/creatinine (Cr) ratio [UACR] <300 mg/g Cr) and upper-normal microalbuminuria (10≤UACR<30 mg/g Cr). This randomized controlled trial enrolled 175 newly diagnosed and untreated hypertensive patients (home systolic blood pressure [SBP]≥135 mmHg; 10≤UACR<300 mg/g Cr of casual spot urine at the first visit to clinic). All patients were treated with irbesartan (week 0). Patients who failed to achieve home SBP ≤125 mmHg on 8-week irbesartan monotherapy (nonresponders, n = 115) were randomized into three additional drug treatment groups: trichlormethiazide (n = 42), efonidipine (n = 39), or amlodipine (n = 34). Irbesartan monotherapy decreased home SBP and first morning urine samples (morning UACR) for 8 weeks (p < 0.0001). At 8 weeks after randomization, all three additional drugs decreased home SBP (p < 0.0002) and trichlormethiazide significantly decreased morning UACR (p = 0.03). Amlodipine decreased morning UACR in patients with microalbuminuria based on casual spot urine samples (p = 0.048). However, multivariate analysis showed that only higher home SBP and UACR at week 8, but not any additional treatments, were significantly associated with UACR reduction between week 8 and week 16. In conclusion, crucial points of the effects of combination therapy on UACR were basal UACR and SBP levels. The effect of trichlormethiazide or amlodipine treatment in combination with irbesartan treatment on microalbuminuria needs to be reexamined based on a larger sample size after considering basal UACR and SBP levels.

Cardiovascular Health in African Americans: A Scientific Statement From the American Heart Association

BACKGROUND AND PURPOSE

Population-wide reductions in cardiovascular disease incidence and mortality have not been shared equally by African Americans. The burden of cardiovascular disease in the African American community remains high and is a primary cause of disparities in life expectancy between African Americans and whites. The objectives of the present scientific statement are to describe cardiovascular health in African Americans and to highlight unique considerations for disease prevention and management.

METHOD

The primary sources of information were identified with PubMed/Medline and online sources from the Centers for Disease Control and Prevention.

RESULTS

The higher prevalence of traditional cardiovascular risk factors (eg, hypertension, diabetes mellitus, obesity, and atherosclerotic cardiovascular risk) underlies the relatively earlier age of onset of cardiovascular diseases among African Americans. Hypertension in particular is highly prevalent among African Americans and contributes directly to the notable disparities in stroke, heart failure, and peripheral artery disease among African Americans. Despite the availability of effective pharmacotherapies and indications for some tailored pharmacotherapies for African Americans (eg, heart failure medications), disease management is less effective among African Americans, yielding higher mortality. Explanations for these persistent disparities in cardiovascular disease are multifactorial and span from the individual level to the social environment.

CONCLUSIONS

The strategies needed to promote equity in the cardiovascular health of African Americans require input from a broad set of stakeholders, including clinicians and researchers from across multiple disciplines.

Association Between Body Mass Index Combined with Albumin: creatinine Ratio and All-cause Mortality in Chinese Population

The association between body mass index (BMI) combined with albumin: creatinine ratio (ACR) and all-cause mortality in the general population has not been established. To address this, we examined a representative sample from the general population of China. The study included 46,854 participants with a follow-up of 4.6 years. Compared to the normal weight with ACR <10 mg/g group (the reference group), the crude hazard ratios (HRs) for all-cause mortality for the underweight with ACR >10 mg/g, normal weight with ACR >10 mg/g, overweight with ACR >10 mg/g, and obese with ACR >10 mg/g groups, were 2.22 (95% CI, 1.41 to 3.49), 1.70 (95% CI, 1.42 to 2.04), 1.52 (95% CI, 1.22 to 1.89), and 2.05 (95% CI, 1.45 to 2.89), respectively. After multivariable adjustments for age, race, comorbidities, and baseline eGFR, the HRs for the underweight with ACR >10 mg/g and normal weight with ACR >10 mg/g groups were 1.85 (95% CI, 1.17 to 2.91) and 1.36 (95% CI, 1.13 to 1.63), respectively. The results indicate that BMI combined with ACR can better predict all-cause mortality than BMI alone in the general Chinese population. Underweight and normal weight people with elevated ACR are at a higher risk of all-cause mortality than those in the same BMI category with ACR <10 mg/g.

Cognitive Function and Kidney Disease: Baseline Data From the Systolic Blood Pressure Intervention Trial (SPRINT)

BACKGROUND

Chronic kidney disease is common and is associated with cardiovascular disease, cerebrovascular disease, and cognitive function, although the nature of this relationship remains uncertain.

STUDY DESIGN

Cross-sectional cohort using baseline data from the Systolic Blood Pressure Intervention Trial (SPRINT).

SETTING & PARTICIPANTS

Participants in SPRINT, a randomized clinical trial of blood pressure targets in older community-dwelling adults with cardiovascular disease, chronic kidney disease, or high cardiovascular disease risk and without diabetes or known stroke, who underwent detailed neurocognitive testing in the cognition substudy, SPRINT-Memory and Cognition in Decreased Hypertension (SPRINT-MIND).

PREDICTORS

Urine albumin-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR).

OUTCOMES

Cognitive function, a priori defined as 5 cognitive domains based on 11 cognitive tests using z scores, and abnormal white matter volume quantified by brain magnetic resonance imaging.

RESULTS

Of 9,361 SPRINT participants, 2,800 participated in SPRINT-MIND and 2,707 had complete data; 637 had brain imaging. Mean age was 68 years, 37% were women, 30% were black, and 20% had known cardiovascular disease. Mean eGFR was 70.8±20.9mL/min/1.73m² and median urine ACR was 9.7 (IQR, 5.7-22.5) mg/g. In adjusted analyses, higher ACR was associated with worse global cognitive function, executive function, memory, and attention, such that each doubling of urine ACR had the same association with cognitive performance as being 7, 10, 6, and 14 months older, respectively. Lower eGFR was independently associated with worse global cognitive function and memory. In adjusted models, higher ACR, but not eGFR, was associated with larger abnormal white matter volume.

LIMITATIONS

Cross-sectional only, no patients with diabetes were included.

CONCLUSIONS

In older adults, higher urine ACR and lower eGFR have independent associations with global cognitive performance with different affected domains. Albuminuria concurrently identifies a higher burden of abnormal brain white matter disease, suggesting that vascular disease may mediate these relationships.

Albuminuria, kidney function, and sudden cardiac death: Findings from The Reasons for Geographic and Racial Differences in Stroke (REGARDS) study

BACKGROUND

Moderate-to-severe kidney disease increases risk for sudden cardiac death (SCD). Limited studies have evaluated how mild degrees of kidney dysfunction impact SCD risk.

OBJECTIVE

The purpose of this study was to evaluate the association of albuminuria, which is one of the earliest biomarkers of kidney injury, and SCD.

METHODS

The Reasons for Geographic and Racial Differences in Stroke (REGARDS) study is a prospective, population-based cohort of U.S. adults. Associations between albuminuria, which is categorized using urinary albumin-to-creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), and SCD were assessed independently and in combination.

RESULTS

After median follow-up of 6.1 years, we identified 335 SCD events. Compared to participants with ACR <15 mg/g, those with higher levels had an elevated adjusted risk of SCD (ACR 15-30 mg/g, hazard ratio [HR] 1.53, 95% confidence interval [CI] 1.11-2.11; ACR >30 mg/g, HR 1.56, 95% CI 1.17-2.11). In contrast, compared to the group with eGFR >90 mL/min/1.73 m2, the adjusted risk of SCD was significantly elevated only among those with eGFR <45 mL/min/1.73 m2 (HR 1.66, 95% CI 1.06-2.58). The subgroup with eGFR <45 mL/min/1.73 m2 (n = 1003) comprised 3.7% of REGARDS, whereas ACR 15-30 mg/g (n = 3089 [11.3%]) and ACR >30 mg/g (n = 4040 [14.8%] were far more common. In the analysis that combined ACR and eGFR categories, albuminuria consistently identified individuals with eGFR ≥60 mLmin/1.73 m2 who were at significantly increased SCD risk.

CONCLUSION

Low levels of kidney injury as measured by ACR predict an increase in SCD risk.

Diabetes, diabetes severity, and coronary heart disease risk equivalence: REasons for Geographic and Racial Differences in Stroke (REGARDS)

BACKGROUND

Evidence is mixed regarding whether diabetes confers equivalent risk of coronary heart disease (CHD) as prevalent CHD. We investigated whether diabetes and severe diabetes are CHD risk equivalents.

METHODS

At baseline, participants in the REasons for Geographic and Racial Differences in Stroke (REGARDS) study (black and white US adults ≥45 years old recruited in 2003-2007) were categorized as having prevalent CHD only (self-reported or electrocardiogram evidence; n = 3,043), diabetes only (self-reported or elevated glucose; n = 4,012), diabetes and prevalent CHD (n = 1,529), and neither diabetes nor prevalent CHD (n = 17,155). Participants with diabetes using insulin and/or with albuminuria (urinary albumin-to-creatinine ratio ≥30 mg/g) were categorized as having severe diabetes. Participants were followed up through 2011 for CHD events (myocardial infarction or fatal CHD).

RESULTS

During a mean follow-up of 5 years, 1,385 CHD events occurred. The hazard ratios of CHD events comparing participants with diabetes only, diabetes, and prevalent CHD and neither diabetes nor prevalent CHD with those with prevalent CHD were 0.65 (95% CI 0.54-0.77), 1.54 (95% CI 1.30-1.83), and 0.41 (95% CI 0.35-0.47), respectively, after adjustment for demographics and risk factors. Compared with participants with prevalent CHD, the hazard ratio of CHD events for participants with severe diabetes was 0.88 (95% CI 0.72-1.09).

CONCLUSIONS

Participants with diabetes had lower risk of CHD events than did those with prevalent CHD. However, participants with severe diabetes had similar risk to those with prevalent CHD. Diabetes severity may need consideration when deciding whether diabetes is a CHD risk equivalent.

Effects of Concurrent Depressive Symptoms and Perceived Stress on Cardiovascular Risk in Low- and High-Income Participants: Findings From the Reasons for Geographical and Racial Differences in Stroke (REGARDS) Study

Background

Psychosocial risk for cardiovascular disease (CVD) may be especially deleterious in persons with low socioeconomic status. Most work has focused on psychosocial factors individually, but emerging research suggests that the confluence of psychosocial risk may be particularly harmful. Using data from the Reasons for Geographical and Racial Differences in Stroke (REGARDS) study, we examined associations among depressive symptoms and stress, alone and in combination, and incident CVD and all‐cause mortality as a function of socioeconomic status.

Methods and Results

At baseline, 22 658 participants without a history of CVD (58.8% female, 41.7% black, mean age 63.9±9.3 years) reported on depressive symptoms, stress, annual household income, and education. Participants were classified into 1 of 3 psychosocial risk groups at baseline: (1) neither depressive symptoms nor stress, (2) either depressive symptoms or stress, or (3) both depressive symptoms and stress. Cox proportional hazards models were used to predict physician‐adjudicated incident total CVD events (nonfatal myocardial infarction, nonfatal stroke, and cardiovascular death) and all‐cause mortality over a median of 7.0 years (interquartile range 5.4–8.3 years) of follow‐up. In fully adjusted models, participants with both depressive symptoms and stress had the greatest elevation in risk of developing total CVD (hazard ratio 1.48, 95% CI 1.21–1.81) and all‐cause mortality (hazard ratio 1.33, 95% CI 1.13–1.56) but only for those with low income (<$35 000) and not high (≥$35 000) income. This pattern of results was not observed in models stratified by education.

Conclusions

Findings suggest that screening for a combination of elevated depressive symptoms and stress in low‐income persons may help identify those at increased risk of incident CVD and mortality.

Five-year mortality outcomes in patients with chronic kidney disease undergoing percutaneous coronary intervention

OBJECTIVE

To examine peri-procedural and long-term outcomes in patients with chronic kidney disease (CKD) undergoing percutaneous coronary interventions (PCI).

BACKGROUND

Patients with advanced CKD are considered high risk when undergoing PCI. Limited published data exist on quantifying risk and assessment of long-term outcomes after PCI in this group.

METHODS

Examining the Cornell Coronary Registry, we prospectively collected data of 6,478 consecutive patients who underwent elective or urgent PCI between 2009 and 2013. Patients were grouped into CKD stages by estimated glomerular filtration rate (eGFR) according to KDOQI guidelines. Procedural and 30-day outcomes are reported with assessment of long-term differences in 5-year all-cause mortality.

RESULTS

Patients were grouped by CKD stages: 1,351 patients with eGFR ≥90 mL/min/1.73 m² (stage 1), 2,882 with eGFR 60-89 (stage 2), 1,742 with eGFR 30-59 (stage 3), 191 with eGFR 15-29 (stage 4), and 312 with eGFR <15 or on dialysis (stage 5). The incidence of post-procedural acute heart failure, stroke, new dialysis requirement, transfusions, and bleeding events were higher in patients with greater CKD stage (P < 0.05). Five-year Kaplan-Meier overall survival among CKD stages 1-5 was 98.1, 95.5, 91.8, 82.5, and 76.9%, respectively (P < 0.001 by log-rank test). The hazard ratios of all-cause mortality for CKD stages 2-5 as compared to stage 1 by multivariate Cox regression analysis were as follows: 1.32 (P = 0.26), 2.04 (P < 0.01), 2.79 (P < 0.01), and 5.49 (P < 0.001).

CONCLUSION

Among patients undergoing PCI, lower GFR is associated with decreased long-term survival. © 2016 Wiley Periodicals, Inc.

Prevalence of Chronic Kidney Disease in Korea: the Korean National Health and Nutritional Examination Survey 2011-2013

Chronic kidney disease is a leading public health problem related to poor quality of life and premature death. As a resource for evidence-informed health policy-making, we evaluated the prevalence of chronic kidney disease using the data of non-institutionalized adults aged ≥ 20 years (n = 15,319) from the Korean National Health and Nutrition Examination Survey in 2011-2013. Chronic kidney disease was defined as a urine albumin-to-creatinine ratio ≥ 30 mg/g or an estimated glomerular filtration rate < 60 mL/min/1.73 m(2) using the Chronic Kidney Disease-Epidemiology Collaboration equation. The total prevalence estimate of chronic kidney disease for adults aged ≥ 20 years in Korea was 8.2%. By disease stage, the prevalence of chronic kidney disease was as follows: stage 1, 3.0%; stage 2, 2.7%; stage 3a, 1.9%; stage 3b, 0.4%; and stages 4-5, 0.2%. When grouped into three risk categories according to the 2012 Kidney Disease: Improving Global Outcomes guidelines, the proportions for the moderately increased risk, high risk, and very high risk categories were 6.5%, 1.2%, and 0.5%, respectively. Factors including older age, diabetes, hypertension, cardiovascular disease, body mass indexes of ≥ 25 kg/m(2) and < 18.5 kg/m(2), and rural residential area were independently associated with chronic kidney disease. Based on this comprehensive analysis, evidence-based screening strategies for chronic kidney disease in the Korean population should be developed to optimize prevention and early intervention of chronic kidney disease and its associated risk factors.

Time to treatment benefit for adult patients with Fabry disease receiving agalsidase β: data from the Fabry Registry

Background

Agalsidase β is a form of enzyme replacement therapy for Fabry disease, a genetic disorder characterised by low α-galactosidase A activity, accumulation of glycosphingolipids and life-threatening cardiovascular, renal and cerebrovascular events. In clinical trials, agalsidase β cleared glycolipid deposits from endothelial cells within 6 months; clearance from other cell types required sustained treatment. We hypothesised that there might be a ‘lag time’ to clinical benefit after initiating agalsidase β treatment, and analysed the incidence of severe clinical events over time in patients receiving agalsidase β.

Methods

The incidence of severe clinical events (renal failure, cardiac events, stroke, death) was studied in 1044 adult patients (641 men, 403 women) enrolled in the Fabry Registry who received agalsidase β (average dose 1 mg/kg every 2 weeks) for up to 5 years.

Results

The incidence of all severe clinical events was 111 per 1000 person-years (95% CI 84 to 145) during the first 6 months. After 6 months, the incidence decreased and remained stable within the range of 40–58 events per 1000 patient-years. The largest decrease in incidence rates was among male patients and those aged ≥40 years when agalsidase β was initiated.

Conclusions

Contrary to the expected increased incidence of severe clinical events with time, adult patients with Fabry disease had decreased incidence of severe clinical events after 6 months treatment with agalsidase β 1 mg/kg every 2 weeks.

Trial registration number

NCT00196742.

Kidney Function and Cardiovascular Events in Postmenopausal Women: The Impact of Race and Ethnicity in the Women's Health Initiative

BACKGROUND

Kidney disease disproportionately affects minority populations, including African Americans and Hispanics; therefore, understanding the relationship of kidney function to cardiovascular (CV) outcomes within different racial/ethnic groups is of considerable interest. We investigated the relationship between kidney function and CV events and assessed effect modification by race/ethnicity in the Women's Health Initiative.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Baseline serum creatinine concentrations (assay traceable to isotope-dilution mass spectrometry standard) of 19,411 postmenopausal women aged 50 to 79 years who self-identified as either non-Hispanic white (n=8,921), African American (n=7,436), or Hispanic (n=3,054) were used to calculate estimated glomerular filtration rates (eGFRs).

PREDICTORS

Categories of eGFR (exposure); race/ethnicity (effect modifier).

OUTCOMES

The primary outcome was the composite of 3 physician-adjudicated CV events: myocardial infarction, stroke, or CV-related death.

MEASUREMENTS

We evaluated the multivariable-adjusted associations between categories of eGFR and CV events using proportional hazards regression and formally tested for effect modification by race/ethnicity.

RESULTS

During a mean follow-up of 7.6 years, 1,424 CV events (653 myocardial infarctions, 627 strokes, and 297 CV-related deaths) were observed. The association between eGFR and CV events was curvilinear; however, the association of eGFR with CV outcomes differed by race (P=0.006). In stratified analyses, we observed that the U-shaped association was present in non-Hispanic whites, whereas African American participants had a rather curvilinear relationship, with lower eGFR being associated with higher CV risk, and higher eGFR, with reduced CV risk. Analyses among Hispanic women were inconclusive owing to few Hispanic women having very low or high eGFRs and very few events occurring in these categories.

LIMITATIONS

Lack of urinary albumin measurements; residual confounding by unmeasured or imprecisely measured characteristics.

CONCLUSIONS

In postmenopausal women, the patterns of association between eGFR and CV risk differed between non-Hispanic whites and African American women.

Race and ethnicity influences on cardiovascular and renal events in patients with diabetes mellitus

BACKGROUND

The incidence of end-stage renal disease (ESRD) has been consistently shown to be higher among blacks and Hispanics compared to whites with unmeasured risk factors and access to care as suggested explanations. In a high-risk cohort with frequent protocol-directed follow-up, we evaluated the influence of race on cardiovascular (CV) outcomes and incidence of ESRD.

METHODS

TREAT was a randomized, double-blind, placebo-controlled study. This secondary analysis focused on role of race on outcomes. TREAT enrolled 4,038 patients with type 2 diabetes, chronic kidney disease (estimated glomerular filtration rate 20-60 mL/min per 1.73 m(2)), and anemia (hemoglobin level ≤11 g/dL) treated with either darbepoetin alfa or placebo. We compared self-described black and Hispanic patients to white patients with regard to baseline characteristics and outcomes, including mortality, CV outcomes (myocardial infarction, stroke, heart failure, resuscitated sudden death, and coronary revascularization), and incident ESRD. Multivariate adjusted Cox models were developed for these outcomes.

RESULTS

Black and Hispanic patients were younger, more likely women, had less prior CV disease, and higher blood pressure. During a mean follow-up of 2.4 years with comparable access to care, blacks and Hispanics had a greater risk of ESRD but a significant lower risk of myocardial infarction and coronary revascularization than whites. After adjusting for confounders, blacks remained at significantly greater risk of ESRD than whites (hazard ratio 1.53, 95% CI 1.26-1.85, P < .001), whereas this ESRD risk did not persist among Hispanics.

CONCLUSION

Despite similar access to care and lower CV event rates, the risk of ESRD was higher among blacks and Hispanics than whites. For blacks, but not Hispanics, this increase was independent of known attributable risk factors.

Estimated glomerular filtration rate and albuminuria for prediction of cardiovascular outcomes: a collaborative meta-analysis of individual participant data

BACKGROUND

The usefulness of estimated glomerular filtration rate (eGFR) and albuminuria for prediction of cardiovascular outcomes is controversial. We aimed to assess the addition of creatinine-based eGFR and albuminuria to traditional risk factors for prediction of cardiovascular risk with a meta-analytic approach.

METHODS

We meta-analysed individual-level data for 637 315 individuals without a history of cardiovascular disease from 24 cohorts (median follow-up 4·2-19·0 years) included in the Chronic Kidney Disease Prognosis Consortium. We assessed C statistic difference and reclassification improvement for cardiovascular mortality and fatal and non-fatal cases of coronary heart disease, stroke, and heart failure in a 5 year timeframe, contrasting prediction models for traditional risk factors with and without creatinine-based eGFR, albuminuria (either albumin-to-creatinine ratio [ACR] or semi-quantitative dipstick proteinuria), or both.

FINDINGS

The addition of eGFR and ACR significantly improved the discrimination of cardiovascular outcomes beyond traditional risk factors in general populations, but the improvement was greater with ACR than with eGFR, and more evident for cardiovascular mortality (C statistic difference 0·0139 [95% CI 0·0105-0·0174] for ACR and 0·0065 [0·0042-0·0088] for eGFR) and heart failure (0·0196 [0·0108-0·0284] and 0·0109 [0·0059-0·0159]) than for coronary disease (0·0048 [0·0029-0·0067] and 0·0036 [0·0019-0·0054]) and stroke (0·0105 [0·0058-0·0151] and 0·0036 [0·0004-0·0069]). Dipstick proteinuria showed smaller improvement than ACR. The discrimination improvement with eGFR or ACR was especially evident in individuals with diabetes or hypertension, but remained significant with ACR for cardiovascular mortality and heart failure in those without either of these disorders. In individuals with chronic kidney disease, the combination of eGFR and ACR for risk discrimination outperformed most single traditional predictors; the C statistic for cardiovascular mortality fell by 0·0227 (0·0158-0·0296) after omission of eGFR and ACR compared with less than 0·007 for any single modifiable traditional predictor.

INTERPRETATION

Creatinine-based eGFR and albuminuria should be taken into account for cardiovascular prediction, especially when these measures are already assessed for clinical purpose or if cardiovascular mortality and heart failure are outcomes of interest. ACR could have particularly broad implications for cardiovascular prediction. In populations with chronic kidney disease, the simultaneous assessment of eGFR and ACR could facilitate improved classification of cardiovascular risk, supporting current guidelines for chronic kidney disease. Our results lend some support to also incorporating eGFR and ACR into assessments of cardiovascular risk in the general population.

FUNDING

US National Kidney Foundation, National Institute of Diabetes and Digestive and Kidney Diseases.

Cause-Specific Deaths in Non-Dialysis-Dependent CKD

CKD is associated with higher risk of death, but details regarding differences in cause-specific death in CKD are unclear. We examined the leading causes of death among a non-dialysis-dependent CKD population using an electronic medical record-based CKD registry in a large healthcare system and the Ohio Department of Health mortality files. We included 33,478 white and 5042 black patients with CKD who resided in Ohio between January 2005 and September 2009 and had two measurements of eGFR<60 ml/min per 1.73 m(2) obtained 90 days apart. Causes of death (before ESRD) were classified into cardiovascular, malignancy, and non-cardiovascular/non-malignancy diseases and non-disease-related causes. During a median follow-up of 2.3 years, 6661 of 38,520 patients (17%) with CKD died. Cardiovascular diseases (34.7%) and malignant neoplasms (31.8%) were the leading causes of death, with malignancy-related deaths more common among those with earlier stages of kidney disease. After adjusting for covariates, each 5 ml/min per 1.73 m(2) decline in eGFR was associated with higher risk of death due to cardiovascular disease (hazard ratio [HR], 1.10; 95% confidence interval [95% CI], 1.08 to 1.12) and non-cardiovascular/non-malignancy diseases (HR, 1.12; 95% CI, 1.09 to 1.14) but not to malignancy. In the adjusted models, blacks had overall-mortality hazard ratios similar to those of whites but higher hazard ratios for cardiovascular deaths. Further studies to confirm these findings and explain the mechanisms for differences are warranted. In addition to lowering cardiovascular burden in CKD, efforts to target known risk factors for cancer at the population level are needed.

Depressive symptoms are associated with incident coronary heart disease or revascularization among blacks but not among whites in the Reasons for Geographical and Racial Differences in Stroke study

PURPOSE

To examine the association of depressive symptoms with coronary heart disease (CHD) end points by race and income.

METHODS

Study participants were blacks and whites (n = 24,443) without CHD at baseline from the national Reasons for Geographical and Racial Differences in Stroke cohort. Outcomes included acute CHD and CHD or revascularization. We estimated race-stratified multivariate Cox proportional hazards models of incident CHD and incident CHD or revascularization with the 4-item Center for Epidemiological Studies Depression Scale, adjusting for risk factors.

RESULTS

Mean follow-up was 4.2 ± 1.5 years; CHD incidence was 8.3 events per 1000 person-years (n = 366) among blacks and 8.8 events per 1000 person-years (n = 613) among whites. After adjustment for age, sex, marital status, region, and socioeconomic status, depressive symptoms were significantly associated with incident CHD among blacks (hazard ratio [HR], 1.39; 95% confidence interval [CI], 1.00-1.91) but not among whites (HR, 1.10; 95% CI, 0.74-1.64). In the fully adjusted model, compared with blacks who reported no depressive symptoms, those reporting depressive symptoms had greater risk for the composite end point of CHD or revascularization (HR, 1.36; 95% CI, 1.01-1.81). Depressive symptoms were not associated with incident CHD end points among whites.

CONCLUSIONS

High depressive symptoms were associated with higher risk of CHD or revascularization for blacks but not whites.

Coronary heart disease risk factors and outcomes in the twenty-first century: findings from the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study

REasons for Geographic and Racial Differences in Stroke (REGARDS) is a longitudinal study supported by the National Institutes of Health to determine the disparities in stroke-related mortality across USA. REGARDS has published a body of work designed to understand the disparities in prevalence, awareness, treatment, and control of coronary heart disease (CHD) and its risk factors in a biracial national cohort. REGARDS has focused on racial and geographical disparities in the quality and access to health care, the influence of lack of medical insurance, and has attempted to contrast current guidelines in lipid lowering for secondary prevention in a nationwide cohort. It has described CHD risk from nontraditional risk factors such as chronic kidney disease, atrial fibrillation, and inflammation (i.e., high-sensitivity C-reactive protein) and has also assessed the role of depression, psychosocial, environmental, and lifestyle factors in CHD risk with emphasis on risk factor modification and ideal lifestyle factors. REGARDS has examined the utility of various methodologies, e.g., the process of medical record adjudication, proxy-based cause of death, and use of claim-based algorithms to determine CHD risk. Some valuable insight into less well-studied concepts such as the reliability of current troponin assays to identify "microsize infarcts," caregiving stress, and CHD, heart failure, and cognitive decline have also emerged. In this review, we discuss some of the most important findings from REGARDS in the context of the existing literature in an effort to identify gaps and directions for further research.

Disparities in the burden, outcomes, and care of chronic kidney disease

PURPOSE OF REVIEW

Racial, ethnic and socioeconomic disparities in chronic kidney disease (CKD) have been documented for decades, yet little progress has been made in mitigating them. Several recent studies offer new insights into the root causes of these disparities, point to areas in which future research is warranted, and identify opportunities for changes in policy and clinical practice.

RECENT FINDINGS

Recently published evidence suggests that geographic disparities in CKD prevalence exist and vary by race. CKD progression is more rapid for racial and ethnic minority groups compared with whites and may be largely, but not completely, explained by genetic factors. Stark socioeconomic disparities in outcomes for dialysis patients exist and vary by race, place of residence, and treatment facility. Disparities in access to living kidney donation may be driven primarily by the socioeconomic status of the donor as opposed to recipient factors.

SUMMARY

Recent studies highlight opportunities to eliminate disparities in CKD, including efforts to direct resources to areas and populations where disparities are most prevalent, efforts to understand how to best use emerging information on the contribution of genetic factors to disparities, and continued work to identify modifiable environmental, social, and behavioral factors for targeted interventions among high-risk populations.

Therapeutic target for nephrotic syndrome: Identification of novel slit diaphragm associated molecules

The slit diaphragm bridging the neighboring foot processes functions as a final barrier of glomerular capillary wall for preventing the leak of plasma proteins into primary urine. It is now accepted that the dysfunction of the sit diaphragm contributes to the development of proteinuria in several glomerular diseases. Nephrin, a gene product of NPHS1, a gene for a congenital nephrotic syndrome of Finnish type, constitutes an extracellular domain of the slit diaphragm. Podocin was identified as a gene product of NPHS2, a gene for a familial steroid-resistant nephrotic syndrome of French. Podocin binds the cytoplasmic domain of nephrin. After then, CD2 associated protein, NEPH1 and transient receptor potential-6 were also found as crucial molecules of the slit diaphragm. In order to explore other novel molecules contributing to the development of proteinuria, we performed a subtraction hybridization assay with a normal rat glomerular RNA and a glomerular RNA of rats with a puromycin aminonucleoside nephropathy, a mimic of a human minimal change type nephrotic syndrome. Then we have found that synaptic vesicle protein 2B, ephrin-B1 and neurexin were already downregulated at the early stage of puromycin aminonucleoside nephropathy, and that these molecules were localized close to nephrin. It is conceivable that these molecules are the slit diaphragm associated molecules, which participate in the regulation of the barrier function. These molecules could be targets to establish a novel therapy for nephrotic syndrome.