Prevalence and Correlates of CKD in Hispanics/Latinos in the United States

Diets high in subsidized foods and chronic kidney disease in Hispanic communities in the United States: the Hispanic Community Health Study/Study of Latinos

Prior research shows that diets high in government subsidized foods may be associated with cardiometabolic disease risk factors. Our aim was to evaluate the relationship between diets high in subsidized foods and the development of chronic kidney disease (CKD) and other cardiometabolic risk factors in United States (US) Hispanics/Latinos. Using data from 16,172 Hispanics/Latino's living in the United States, we used the Cochran-Armitage test to assess the relationship between subsidized foods in the diets of participants and baseline characteristics. We used survey-weighted Poisson regression models to examine whether intake of subsidized foods was associated with incident CKD or cardiometabolic risk factors. Several baseline characteristics were associated with higher subsidized food scores. Higher subsidized food scores were not associated with incident CKD or cardiometabolic risk factors. These findings may be useful for future researchers, clinicians, and nutritional policy advocates who are interested in the way Hispanic and Latinos consume foods subsidized by the US government and the structural factors that may shape observed dietary and disease patterns.

Preferences of people with chronic kidney disease regarding digital health interventions that promote healthy lifestyle: qualitative systematic review with meta-ethnography

OBJECTIVES

Diet and physical activity are crucial for people with chronic kidney disease (CKD) to maintain good health. Digital health interventions can increase access to lifestyle services. However, consumers' perspectives are unclear, which may reduce the capacity to develop interventions that align with specific needs and preferences. Therefore, this review aims to synthesise the preferences of people with CKD regarding digital health interventions that promote healthy lifestyle.

DESIGN

Qualitative systematic review with meta-ethnography.

DATA SOURCES

Databases Scopus, CENTRAL, MEDLINE, CINAHL and SPORTDiscus were searched between 2000 and 2023.

ELIGIBILITY CRITERIA

Primary research papers that used qualitative exploration methods to explore the preferences of adults with CKD (≥18 years) regarding digital health interventions that promoted diet, physical activity or a combination of these health behaviours.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers screened title, abstract and full text. Discrepancies were resolved by a third reviewer. Consumers' quotes were extracted verbatim and synthesised into higher-order themes and subthemes.

RESULTS

Database search yielded 5761 records. One record was identified following communication with a primary author. 15 papers were included. These papers comprised 197 consumers (mean age 51.0±7.2), including 83 people with CKD 1-5; 61 kidney transplant recipients; 53 people on dialysis. Sex was reported in 182 people, including 53% male. Five themes were generated regarding consumers' preferences for digital lifestyle interventions. These included simple instruction and engaging design; individualised interventions; virtual communities of care; education and action plans; and timely reminders and automated behavioural monitoring.

CONCLUSION

Digital health interventions were considered an important mechanism to access lifestyle services. Consumers' preferences are important to ensure future interventions are tailored to specific needs and goals. Future research may consider applying the conceptual framework of consumers' preferences in this review to develop and evaluate the effect of a digital lifestyle intervention on health outcomes.

PROSPERO REGISTRATION NUMBER

CRD42023411511.

Prevalence of infertility and pregnancy loss among individuals with kidney disease in the Hispanic Community Health Study/Study of Latinos

BACKGROUND

Hispanic/Latino individuals are less likely to receive optimal treatment for chronic kidney disease than non-Hispanic whites. This may be particularly detrimental for women of reproductive age as chronic kidney disease increases risk for infertility, menstrual irregularities, and pregnancy loss. While these maternal outcomes have been associated with advanced chronic kidney disease, their occurrence in early chronic kidney disease is unclear.

OBJECTIVES/DESIGN

Using baseline (2008-2011) and second study visit (2014-2017) data from the Hispanic Community Health Study/Study of Latinos, we retrospectively assessed the prevalence of chronic kidney disease as well as the association between chronic kidney disease and self-reported infertility, cessation of menses, hysterectomy, and nonviable pregnancy loss (experienced at less than 24 weeks gestation) in women of reproductive age (18-45 years).

METHODS

Multivariable survey logistic regression analyses determined the unadjusted and multivariable-adjusted prevalence odds ratios with 95% confidence intervals between chronic kidney disease and the separate outcomes.

RESULTS

Among 2589 Hispanic/Latino women included (mean age = 31.4 years), 4.6% were considered to have chronic kidney disease. In adjusted analyses, women with chronic kidney disease did not have a significantly increased odds of infertility (odds ratio = 1.02, 95% confidence interval = 0.42-2.49), cessation of menses (odds ratio = 1.25, 95% confidence interval = 0.52-3.04), or hysterectomy (odds ratio = 1.17, 95% confidence interval = 0.61-2.25) compared to those without chronic kidney disease. In those with chronic kidney disease, the adjusted odds of a nonviable pregnancy loss occurring after baseline visit were increased (odds ratio = 2.11, 95% confidence interval = 0.63-7.02) but not statistically significance.

CONCLUSION

The presence of early stage chronic kidney disease did not confer a significant risk of infertility, cessation of menses, or nonviable pregnancy loss.

Community-Engaged Research (CEnR) to Address Gaps in Chronic Kidney Disease Education among Underserved Latines-The CARE Study

Ensuring equitable chronic kidney disease (CKD) education for Latine patients with low health literacy and low English proficiency stands as a critical challenge, and the "Caridad Awareness and Education" (CARE) initiative represents our ongoing effort to address this imperative issue. In collaboration with twenty-three patients living with CKD, diabetes and/or hypertension and twelve trained Community Health Workers (CHWs) from diverse Latine subgroups, we conducted a research initiative funded by the National Kidney Foundation. Our primary objective was to co-design and test culturally tailored patient education materials (PEMs) for underserved Latine adults at risk for or diagnosed with CKD. We effectively integrated Community-Engaged Research (CEnR) principles with a Human-Centered Design (HCD) approach to create a range of CKD-PEM prototypes in Spanish. Patient preferences for printed educational materials were clear. They favored printed materials that incorporated visual content with concise text over digital, email, texts, or online resources and personalized phone outreach and the involvement of CHWs. Additionally, patients identified their unwavering commitment to their families as a forceful motivator for caring for their kidney health. Currently, a culturally and linguistically tailored CKD flipchart for one-on-one education, led by CHWs, is undergoing a pilot testing phase involving a sample of one hundred Latine patients at risk for or diagnosed with CKD. This innovative approach signifies a commitment to amplifying the insights and expertise of the Latine community afflicted by kidney health disparities, effectively embracing a CEnR to forge meaningful and impactful CKD-PEMs.

Proceedings of a Workshop to Promote Community Health Worker Interventions in Nephrology

ABSTRACT

Latinx populations face a higher burden of kidney failure and associated negative outcomes compared with non-Latinx White populations, despite sharing a similar prevalence of CKD. Community health worker (CHW) interventions have been shown to improve outcomes for Latinx individuals, but they are largely underutilized in kidney disease. We convened a workshop of four ongoing kidney disease CHW programs to identify successes, challenges, potential solutions, and needed research to promote CHW programs for Latinx individuals with kidney disease. Key points from the workshop and recommendations for intervention and research are highlighted. Facilitators of program success included prioritizing trust-building with participants, enabling participants to determine what aspects of the intervention were needed, providing participants with tools to help themselves and others after the intervention, and taking a trauma-informed approach to relationships. Challenges included persistent systemic barriers despite successful care navigation and low recruitment and retention. Research is needed to capture the effect of CHW interventions on outcomes and to determine how to implement CHW interventions for people with kidney disease nationwide.

Receiving hemodialysis in Hispanic ethnic dense communities is associated with better adherence and outcomes among young patients: a retrospective analysis of the Dialysis Outcomes and Practice Patterns Study

BACKGROUND

Hispanic ethnic density (HED) is a marker of better health outcomes among Hispanic patients with chronic disease. It is unclear whether community HED is associated with mortality risk among ethnically diverse patients receiving maintenance hemodialysis.

METHODS

A retrospective analysis of patients in the United States cohort of the Dialysis Outcomes and Practice Patterns Study (DOPPS) database (2011-2015) was conducted (n = 4226). DOPPS data was linked to the American Community Survey database by dialysis facility zip code to obtain % Hispanic residents (HED). One way ANOVA and Kruskal Wallis tests were used to estimate the association between tertiles of HED with individual demographic, clinical and adherence characteristics, and facility and community attributes. Multivariable Cox proportional hazards models were used to estimate the mortality hazard ratio (HR) and 95% CIs by tertile of HED, stratified by age; a sandwich estimator was used to account for facility clustering.

RESULTS

Patients dialyzing in facilities located in the highest HED tertile communities were younger (61.4 vs. 64.4 years), more commonly non-White (62.4% vs. 22.1%), had fewer comorbidities, longer dialysis vintage, and were more adherent to dialysis treatment, but had fewer minutes of dialysis prescribed than those in the lowest tertile. Dialyzing in the highest HED tertile was associated with lower hazard of mortality (HR, 0.86; 95% CI, 0.72-1.00), but this association attenuated with the addition of individual race/ethnicity (HR, 0.92; 95% CI, 0.78-1.09). In multivariable age-stratified analyses, those younger than 64 showed a lower hazard for mortality in the highest (vs. lowest) HED tertile (HR, 0.66; 95% CI, 0.49-0.90). Null associations were observed among patients ≥ 64 years.

CONCLUSIONS

Treating in communities with greater HED and racial/ethnic integration was associated with lower mortality among younger patients which points to neighborhood context and social cohesion as potential drivers of improved survival outcomes for patients receiving hemodialysis.

Facilitating Medical Care for Latinx Individuals at Risk for CKD: A Pilot Intervention

Rationale and Objective

Latinx individuals are at a higher risk for kidney failure than non-Latinx White individuals; however, they are less likely to receive pre-kidney failure medical care. The objective of this study was to determine the feasibility and acceptability of a community health worker (CHW) intervention that facilitated access to medical care for Latinx individuals.

Study Design

Single-arm prospective study.

Setting and Participants

Latinx adults were found to have albuminuria or risk factors for kidney disease at community screening events in Austin, Texas.

Intervention

A 6-month CHW intervention that facilitated the following: (1) obtaining medical insurance; (2) medical care coordination with primary and nephrology care; (3) kidney disease education; and (4) connection with local resources to address health-related social needs.

Outcomes

Recruitment, retention, medical care linkage, and participant and CHW-reported satisfaction with the intervention.

Results

Of the 173 individuals who attended the 2 community screening events, 49 agreed to participate in the study, of whom, 51% were men with a mean ± standard deviation (SD) age of 45 ± 14 years, and all self-identified as Mexican or Chicano. The mean ± SD estimated glomerular filtration rate (eGFR) was 110 ± 21 mL/min/1.73 m² and 41% of the participants reported a urine albumin-creatinine ratio of ≥30 mg/g. Among those enrolled, 28 of the 49 (57%) completed at least 1 CHW visit, and 20 of 49 (41%) completed the intervention. 7 individuals who needed assistance with insurance obtained insurance, and 15 of 20 (75%) scheduled an appointment with a primary care physician within 180 days. Participants reported that the US health care previously seemed inaccessible but gained insurance, the ability to navigate the system, and the ability to help others in their community to access medical care because of the program.

Limitations

Small sample size and a single community may limit generalizability.

Conclusions

We reported the acceptability of a CHW intervention. We encountered challenges with feasibility and identified strategies to overcome them. Studies are needed to test the effect of CHW interventions on outcomes and kidney health disparities.

Funding

National Kidney Foundation young investigator research grant to Dr Novick.

Plain Language Summary

Latinx individuals are at a higher risk for kidney failure than non-Latinx White individuals; however, they are less likely to receive pre-kidney failure medical care. We piloted a community health worker intervention that connected people with risk factors or showed evidence of kidney dysfunction at community screening events with medical care. Our findings indicate the acceptability of the intervention. We encountered challenges with feasibility and identified strategies to overcome them.

Circulating Metabolites Associated with Albuminuria in a Hispanic/Latino Population

BACKGROUND

Albuminuria is associated with metabolic abnormalities, but these relationships are not well understood. We studied the association of metabolites with albuminuria in Hispanic/Latino people, a population with high risk for metabolic disease.

METHODS

We used data from 3736 participants from the Hispanic Community Health Study/Study of Latinos, of which 16% had diabetes and 9% had an increased urine albumin-to-creatinine ratio (UACR). Metabolites were quantified in fasting serum through nontargeted mass spectrometry (MS) analysis using ultra-performance liquid chromatography-MS/MS. Spot UACR was inverse normally transformed and tested for the association with each metabolite or combined, correlated metabolites, in covariate-adjusted models that accounted for the study design. In total, 132 metabolites were available for replication in the Hypertension Genetic Epidemiology Network study ( n =300), and 29 metabolites were available for replication in the Malmö Offspring Study ( n =999).

RESULTS

Among 640 named metabolites, we identified 148 metabolites significantly associated with UACR, including 18 novel associations that replicated in independent samples. These metabolites showed enrichment for D-glutamine and D-glutamate metabolism and arginine biosynthesis, pathways previously reported for diabetes and insulin resistance. In correlated metabolite analyses, we identified two modules significantly associated with UACR, including a module composed of lipid metabolites related to the biosynthesis of unsaturated fatty acids and alpha linolenic acid and linoleic acid metabolism.

CONCLUSIONS

Our study identified associations of albuminuria with metabolites involved in glucose dysregulation, and essential fatty acids and precursors of arachidonic acid in Hispanic/Latino population.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_02_08_CJN09070822.mp3.

Polygenic risk scores and kidney traits in the Hispanic/Latino population: The Hispanic Community Health Study/Study of Latinos

Estimated glomerular filtration rate (eGFR) is used to evaluate kidney function and determine the presence of chronic kidney disease (CKD), a highly prevalent disease in the US^{1 , 2 , 3} that varies among subgroups of Hispanic/Latino individuals.^{4 , 5} The polygenic risk score (PRS) is a popular method that uses large genome-wide association studies (GWASs) to provide a strong estimate of disease risk.⁷ However, due to the limited availability of summary statistics from GWAS meta-analyses based on Hispanic/Latino populations, PRSs can only be computed using different ancestry GWASs. The performance of eGFR PRSs derived from other GWAS reference populations for Hispanic/Latino population has not been examined. We compared PRS constructions for eGFR prediction in Hispanic/Latino individuals using GWAS-significant variants, clumping and thresholding (C&T),⁸ and PRS-CS,²² as well as a combination of PRSs calculated with different reference GWAS meta-analyses from European and multi-ethnic studies in Hispanic/Latino individuals from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL). All eGFR PRSs were highly associated with eGFR (p < 1E-20). Additionally, eGFR PRSs were significantly associated with lower risk of prevalent CKD at visit 1 or 2 and incident CKD at visit 2, with the combined PRSs having the best performance. These PRS findings were replicated in an additional dataset of Hispanic/Latino individuals using data from the Women's Health Initiative SNP Health Association Resource (WHI-SHARe).¹⁷.

Examining post-donation outcomes in Hispanic/Latinx living kidney donors in the United States: A systematic review

We conducted a systematic review to assess outcomes in Hispanic donors and explore how Hispanic ethnicity was characterized. We searched PubMed, EMBASE, and Scopus through October 2021. Two reviewers independently screened study titles, abstracts, and full texts; they also qualitatively synthesized results and independently assessed quality of included studies. Eighteen studies met our inclusion criteria. Study sample sizes ranged from 4007 to 143,750 donors and mean age ranged from 37 to 54 years. Maximum follow-up time of studies varied from a perioperative donor nephrectomy period to 30 years post-donation. Hispanic donors ranged between 6% and 21% of the donor populations across studies. Most studies reported Hispanic ethnicity under race or a combined race and ethnicity category. Compared to non-Hispanic White donors, Hispanic donors were not at increased risk for post-donation mortality, end-stage kidney disease, cardiovascular disease, non-pregnancy-related hospitalizations, or overall perioperative surgical complications. Compared to non-Hispanic White donors, most studies showed Hispanic donors were at higher risk for diabetes mellitus following nephrectomy; however, mixed findings were seen regarding the risk for post-donation chronic kidney disease and hypertension. Future studies should evaluate cultural, socioeconomic, and geographic differences within the heterogeneous Hispanic donor population, which may further explain variation in health outcomes.

Associations of sodium and potassium intake with chronic kidney disease in a prospective cohort study: findings from the Hispanic Community Health Study/Study of Latinos, 2008-2017

BACKGROUND

According to dietary recommendations, reduction of sodium intake has potential to reduce Chronic Kidney Disease (CKD) risk; however the role of dietary potassium and the sodium -to- potassium ratio in the development of CKD is unclear.

METHODS

We studied 9778 participants of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) from four US urban communities. Participants were aged 18-74 yrs., free from CKD at baseline in 2008-2011 and re-examined between 2014 and - 2017. Dietary intake of sodium, potassium and the ratio of dietary sodium -to- potassium were measured from two baseline 24-h dietary recalls. Incident CKD was defined as: 1) estimated glomerular filtration rate (eGFR) decline of 1 unit per year and eGFR < 60 ml/min/1.73m2 or 2) albumin to creatinine ratio ≥ 30 mg/g at the follow-up visit. We used multivariable survey weighted Poisson regression to estimate adjusted incident rates of incident CKD.

RESULTS

At baseline, mean age was 41 years. Average follow up time was 6.2 years. From fully adjusted Poisson regression analyses, self-reported sodium intake was not associated with incident CKD. However, for each 500 mg decrement in potassium intake, there was an 11% increase risk of incident CKD (IRR = 1.11, 95% CI = 1.00, 1.24). Additionally, every 1 M ratio increment of sodium -to -potassium ratio was associated with a 21% increased risk of incident CKD (IRR = 1.21, 95% CI = 1.02, 1.45), p < 0.05).

CONCLUSIONS

We conclude that diets low in potassium and high in sodium are associated with increased risk of developing chronic kidney disease among healthy US Hispanic/Latino adults.

Genome-Wide Admixture Mapping of Estimated Glomerular Filtration Rate and Chronic Kidney Disease Identifies European and African Ancestry-of-Origin Loci in Hispanic and Latino Individuals in the United States

BACKGROUND

Admixture mapping is a powerful approach for gene mapping of complex traits that leverages the diverse genetic ancestry in populations with recent admixture, such as Hispanic or Latino individuals in the United States. These individuals have an increased risk of CKD.

METHODS

We performed genome-wide admixture mapping for both CKD and eGFR in a sample of 12,601 participants from the Hispanic Community Health Study/Study of Latinos, with validation in a sample of 8191 Black participants from the Women's Health Initiative (WHI). We also compared the findings with those from a conventional genome-wide association study.

RESULTS

Three novel ancestry-of-origin loci were identified on chromosomes 2, 14, and 15 for CKD and eGFR. The chromosome 2 locus comprises two European ancestry regions encompassing the FSHR and NRXN1 genes, with European ancestry at this locus associated with increased CKD risk. The chromosome 14 locus, found within the DLK1-DIO3 imprinted domain, was associated with lower eGFR and driven by European ancestry. The eGFR-associated locus on chromosome 15 included intronic variants of RYR3 and was within an African-specific genomic region associated with higher eGFR. The genome-wide association study failed to identify significant associations in these regions. We validated the chromosome 14 and 15 loci associated with eGFR in the WHI Black participants.

CONCLUSIONS

This study provides evidence of shared ancestry-specific genomic regions influencing eGFR in Hispanic or Latino individuals and Black individuals and illustrates the potential for leveraging genetic ancestry in recently admixed populations for the discovery of novel candidate loci for kidney phenotypes.

Association of elevated serum aminotransferase levels with chronic kidney disease measures: hispanic community health study/study of latinos

Background

Previous studies have shown an association between non-alcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD), but it is unclear whether the association is independent of metabolic syndrome.

Methods

Data from 13,006 participants aged 18 to 74 years in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) without viral hepatitis, excessive alcohol consumption, or high transferrin saturation levels were analyzed. Suspected NAFLD was defined as presence of sex-specific elevations in serum aminotransferase levels (aspartate aminotransferase (AST) > 37 U/L or alanine aminotransferase (ALT) > 40 U/L for men and AST or ALT > 31 U/L for women). Logistic regression was used to examine cross-sectional associations of elevated serum aminotransferase levels with low estimated glomerular filtration rate (eGFR < 60 ml/min/1.73 m² based on cystatin C), and with high urinary albumin-to-creatinine ratio (UACR) (> 17 mg/g in men and > 25 mg/ g in women) in separate models adjusting for demographic characteristics and metabolic syndrome.

Results

Mean (SD) age was 41 (0.27) years, and 45 % were male. Elevated serum aminotransferase levels were noted in 18.8 % of the population and were associated with greater odds of high UACR (OR = 1.31; 95 % CI = 1.10, 1.56) after adjusting for demographic characteristics; this association became non-significant after adjustment for metabolic syndrome (OR = 1.11, 95 % CI = 0.92, 1.33). In contrast, elevated serum aminotransferase levels were not associated with low eGFR (odds ratio (OR) = 0.73; 95 % confidence interval (CI) = 0.45, 1.18) after adjusting for covariates.

Conclusions

In this sample of diverse U.S. Hispanic Latino adults, elevated serum aminotransferase levels were not independently associated with measures of CKD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02483-y.

Perspectives on Kidney Disease Education and Recommendations for Improvement Among Latinx Patients Receiving Emergency-Only Hemodialysis

IMPORTANCE

In most states, undocumented Latinx immigrants with kidney failure receive dialysis in acute care settings on an emergency-only basis. How much kidney disease education Latinx immigrants receive and how to improve kidney disease education and outreach among Latinx populations are unknown.

OBJECTIVE

To understand the kidney disease educational gaps of Latinx individuals who need but lack access to scheduled outpatient dialysis.

DESIGN, SETTING, AND PARTICIPANTS

This qualitative study used semistructured interviews in a Texas hospital system from March 2020 to January 2021 with 15 individuals who received emergency-only dialysis when they were first diagnosed with kidney failure. Demographic information was collected, and a thematic analysis was performed using the constant comparative method on interviews after they were audio-recorded, translated, and transcribed verbatim. Data analysis was performed from April 2020 to February 2021.

MAIN OUTCOMES AND MEASURES

Subthemes and themes from semistructured interviews.

RESULTS

All 15 persons interviewed (9 male individuals [60%]; mean [SD] age, 51 [17] years) identified as Hispanic, 11 (73%) were born in Mexico, and none reported knowing about their kidney disease more than 6 months before starting dialysis. The themes identified were (1) lack of kidney disease awareness, (2) education provided was incomplete and poor quality, (3) lack of culturally concordant communication and care, (4) elements that Latinx patients receiving emergency-only dialysis want in their education, (5) facilitators of patient activation and coping, and (6) Latinx patient recommendations to improve community outreach.

CONCLUSIONS AND RELEVANCE

Latinx adults receiving emergency-only dialysis are usually unaware of their kidney disease until shortly before or after they start dialysis, and the education they receive is poor quality and often not culturally tailored. Participants made feasible recommendations on how to improve education and outreach among Latinx communities.

Prevalence and Risk Factors for Chronic Kidney Disease in Belize: A Population-based Survey

Background

Health resources supporting dialysis and chronic kidney disease (CKD) patients are limited in Central America, and little information about the prevalence and risk factors for CKD in this region is available.

Methods

The Survey of Risk Factors for Chronic Kidney Disease was a population-based cross-sectional study conducted throughout Belize in 2017. The study aimed to assess the prevalence and risk factors for CKD via structured questionnaires and clinical measurements in Belizeans aged 20-55 years. A two-stage stratified sampling technique was applied. CKD was defined as an estimated glomerular filtration rate < 60 mL/min/1·73 m² or the presence of proteinuria.

Findings

A total of 7,506 adults with a mean age of 34·6 years old completed the survey; 53·2% were women. The overall CKD prevalence was 13·7%. Women had a higher CKD prevalence than men (14·8% vs. 12·5%), and the overall awareness of CKD was low (3·7%). The prevalences of stage 1, 2, 3a, 3b, 4, and 5 CKD were 2·85%, 2·93%, 6·59%, 1·10%, 0·18%, and 0·06%, respectively. Older age, female sex, Mestizo/Hispanic ethnicity, diabetes, hypertension, hypercholesterolaemia, and obesity were identified as independent risk factors for CKD.

Interpretation

The prevalence of CKD was 13·7% in Belizeans aged 20-55 years. The study confirms the high burden of CKD in Belize and provides important epidemiological information for Central America. Case management systems and surveillance programmes targeting high-risk populations are crucial for ameliorating the burden of CKD.

Funding

Capacity Building Project for the Prevention and Control of Chronic Renal Failure in Belize.

Periodontal Disease and Incident CKD in US Hispanics/Latinos: The Hispanic Community Health Study/Study of Latinos

Rationale & Objective

Recent studies suggest that periodontal disease may be associated with incident chronic kidney disease (CKD). However, studies have focused on older populations, and US Hispanics/Latinos were not well represented.

Study Design

Observational cohort.

Setting & Participants

We analyzed data from the Hispanic Community Health Study/Study of Latinos who completed a baseline visit with a periodontal examination and a follow-up visit, and did not have CKD at baseline.

Predictors

Predictors included ≥30% of sites with clinical attachment loss ≥3 mm, ≥30% of sites with probing depth ≥4 mm, percentage of sites with bleeding on probing, and absence of functional dentition (<21 permanent teeth present).

Outcomes

Outcomes were incident low estimated glomerular filtration rate (eGFR) (eGFR <60 mL/min/1.73 m² and decline in eGFR ≥1 mL/min/year); incident albuminuria (urine albumin:creatinine ratio [ACR] ≥30 mg/g); and change in eGFR and ACR.

Analytic Approach

Poisson and linear regression.

Results

For the sample (n = 7.732), baseline mean age was 41.5 years, 45.2% were male, 11.7% had ≥30% of sites with clinical attachment loss ≥3 mm, 5.1% had ≥30% of sites with probing depth ≥4 mm, 30.7% had ≥50% of sites with bleeding on probing, and 16.2% had absent functional dentition. During a median follow-up of 5.9 years, 149 patients developed low eGFR and 415 patients developed albuminuria. On multivariable analysis, presence versus absence of ≥30% of sites with probing depth ≥4 mm and absence of functional dentition were each associated with increased risk for incident low eGFR (incident density ratio, 2.31; 95% CI, 1.14-4.65 and 1.65, 95% CI, 1.01-2.70, respectively). None of the other predictors were associated with outcomes.

Limitations

Only a single kidney function follow-up measure.

Conclusions

In this cohort of US Hispanics/Latinos, we found that select measures of periodontal disease were associated with incident low eGFR. Future work is needed to assess whether the treatment of periodontal disease may prevent CKD.

Therapeutic effects of exercise interventions for patients with chronic kidney disease: protocol for an overview of systematic reviews and meta-analyses of clinical trials

INTRODUCTION

An increasing number of systematic reviews and meta-analyses of clinical trials have begun to investigate the effects of exercise interventions in patients with chronic kidney disease (CKD). To systematically appraise and synthesise these results, we will conduct an overview of systematic reviews and meta-analyses.

METHODS AND ANALYSIS

This is a protocol for an overview of systematic reviews and meta-analyses. We will search four databases: PubMed, Embase, Web of Science Core Collection and Cochrane Central Registry of Controlled Trials. Systematic reviews and meta-analyses of clinical trials evaluating the effect of exercise interventions on patients with CKD will be included. Two independent authors will screen titles and abstracts retrieved in the literature search and select studies meeting the eligibility criteria for full-text review. The methodological quality of the included reviews will be assessed using A Measurement Tool to Assess Systematic Reviews-2. We estimate the summary effects for each meta-analyses based on the standardised mean difference and its 95% CI. Additionally, the heterogeneity will be assessed by I2 evidence of small-study effect and the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation system.

ETHICS AND DISSEMINATION

Ethics approval are not required as no private information from individuals is collected. The results will be published in a peer-reviewed journal or disseminated in relevant conferences.

PROSPERO REGISTRATION NUMBER

CRD42020223591.

Sedentary Behavior and Change in Kidney Function: The Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

BACKGROUND

There is accumulating evidence linking prolonged sedentary time to adverse health outcomes. The effect of sedentary behavior on kidney function has not been evaluated in US Hispanics/Latinos, a population disproportionately affected by CKD.

METHODS

We evaluated the association between accelerometer-measured (1 week) sedentary time at baseline and kidney function among 7134 adults without CKD at entry in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), who completed a baseline visit with accelerometry (2008-2011) and a follow-up visit (2014-2017). Outcomes included: (1) change in kidney function (eGFR and urine albumin-to-creatinine ratio, ACR), (2) incident low eGFR (eGFR <60 ml/min per 1.73 m2 and eGFR decline ≥1 ml/min per year), and (3) incident albuminuria (ACR ≥17 mg/g in men or ≥25 mg/g in women). Linear regression using survey procedures was used to evaluate change in kidney function (eGFR and ACR), and Poisson regression with robust variance was used to evaluate incident low eGFR and albuminuria.

RESULTS

The median sedentary time was 12 hours/d. Over a median follow-up of 6.1 years, the mean relative change in eGFR was -0.50% per year, and there were 167 incident low eGFR events. On multivariable analysis, each 1 hour increase in sedentary time was associated with a longitudinal decline in eGFR (-0.06% per year, 95% CI, -0.10 to -0.02). There was a significant interaction with sex, and on stratified analyses, higher sedentary time was associated with eGFR decline in women but not men. There was no association between sedentary time and the other outcomes.

CONCLUSIONS

Sedentary time was associated with a small longitudinal decline in eGFR, which could have important implications in a population that experiences a disproportionate burden of CKD but further investigation is needed.

COVID-19 and Kidney Disease Disparities in the United States

Racial, ethnic, socioeconomic, age, and sex-related health disparities in kidney disease are prominent in the United States. The Coronavirus Disease 2019 (COVID-19) pandemic has disproportionately affected marginalized populations. Older adults, people experiencing unstable housing, racial and ethnic minorities, and immigrants are potentially at increased risk for infection and severe complications from COVID-19. The direct and societal effects of the pandemic may increase risk of incident kidney disease and lead to worse outcomes for those with kidney disease. The rapid transition to telemedicine potentially limits access to care for older adults, immigrants, and people experiencing unstable housing. The economic impact of the pandemic has had a disproportionate effect on women, minorities, and immigrants, which may limit their ability to manage kidney disease and lead to complications or kidney disease progression. We describe the impact of COVID-19 on marginalized populations and highlight how the pandemic may exacerbate existing disparities in kidney disease.

RENA Study: Cross-Sectional Study to Evaluate CKD Prevalence in Portugal

INTRODUCTION

Chronic kidney disease (CKD) is a major global public health problem associated with increased risk of cardiovascular morbidity, premature mortality, and decreased quality of life. In Portugal, the PREVADIAB study showed a prevalence of CKD stages 3-5 of 6.1%. To overcome the limitations of the PREVADIAB study, the RENA study aimed to provide an estimate of the prevalence of CKD at a national level and to characterize CKD patients.

METHODS

This was a cross-sectional study including users of Primary Health Care Units aged 18 or more. After obtaining written informed consent, sociodemographic and clinical data were recorded through a structured questionnaire, anthropometric measurements were taken, and blood and urine samples were collected. All participants initially meeting the criteria for CKD were contacted at least 3 months after the initial assessment for confirmation of the analytical results.

RESULTS

A total of 3,135 individuals were included, 65.4% were female, and the mean age was 56.7 ± 15.9 years. The prevalence of hypertension, dyslipidemia, and diabetes was 38, 32, and 16%, respectively, and 31% were obese. After data adjustment by gender, age group, and geographical region, the global prevalence of CKD was 20.9% (95% CI: 6.5-35.3%), with no differences between genders and a significant increase with the advance of the age groups.

CONCLUSION

Our study showed a CKD prevalence above the worldwide and Europe average. Despite the study limitations, it has become clear that it is urgent to identify CKD patients earlier and to develop awareness and educational programs to prevent CKD and its associated diseases.

Genome-Wide Association of Kidney Traits in Hispanics/Latinos Using Dense Imputed Whole-Genome Sequencing Data: The Hispanic Community Health Study/Study of Latinos

BACKGROUND

Genetic factors that influence kidney traits have been understudied for low-frequency and ancestry-specific variants.

METHODS

This study used imputed whole-genome sequencing from the Trans-Omics for Precision Medicine project to identify novel loci for estimated glomerular filtration rate and urine albumin-to-creatinine ratio in up to 12 207 Hispanics/Latinos. Replication was performed in the Women's Health Initiative and the UK Biobank when variants were available.

RESULTS

Two low-frequency intronic variants were associated with estimated glomerular filtration rate (rs58720902 at AQR, minor allele frequency=0.01, P=1.6×10^-8) or urine albumin-to-creatinine ratio (rs527493184 at ZBTB16, minor allele frequency=0.002, P=1.1×10^-8). An additional variant at PRNT (rs2422935, minor allele frequency=0.54, P=2.89×10^-8) was significantly associated with estimated glomerular filtration rate in meta-analysis with replication samples. We also identified 2 known loci for urine albumin-to-creatinine ratio (BCL2L11 rs116907128, P=5.6×10^-8 and HBB rs344, P=9.3×10^-11) and validated 8 loci for urine albumin-to-creatinine ratio previously identified in the UK Biobank.

CONCLUSIONS

Our study shows gains in gene discovery when using dense imputation from multi-ethnic whole-genome sequencing data in admixed Hispanics/Latinos. It also highlights limitations in genetic research of kidney traits, including the lack of suitable replication samples for variants that are more common in non-European ancestry and those at low frequency in populations.

Incident Chronic Kidney Disease Risk among Hispanics/Latinos in the United States: The Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

BACKGROUND

Although Hispanics/Latinos in the United States are often considered a single ethnic group, they represent a heterogenous mixture of ancestries who can self-identify as any race defined by the U.S. Census. They have higher ESKD incidence compared with non-Hispanics, but little is known about the CKD incidence in this population.

METHODS

We examined rates and risk factors of new-onset CKD using data from 8774 adults in the Hispanic Community Health Study/Study of Latinos. Incident CKD was defined as eGFR <60 ml/min per 1.73 m² with eGFR decline ≥1 ml/min per 1.73 m² per year, or urine albumin/creatinine ratio ≥30 mg/g. Rates and incidence rate ratios were estimated using Poisson regression with robust variance while accounting for the study's complex design.

RESULTS

Mean age was 40.3 years at baseline and 51.6% were women. In 5.9 years of follow-up, 648 participants developed CKD (10.6 per 1000 person-years). The age- and sex-adjusted incidence rates ranged from 6.6 (other Hispanic/mixed background) to 15.0 (Puerto Ricans) per 1000 person-years. Compared with Mexican background, Puerto Rican background was associated with 79% increased risk for incident CKD (incidence rate ratios, 1.79; 95% confidence interval, 1.33 to 2.40), which was accounted for by differences in sociodemographics, acculturation, and clinical characteristics. In multivariable regression analysis, predictors of incident CKD included BP >140/90 mm Hg, higher glycated hemoglobin, lower baseline eGFR, and higher baseline urine albumin/creatinine ratio.

CONCLUSIONS

CKD incidence varies by Hispanic/Latino heritage and this disparity may be in part attributed to differences in sociodemographic characteristics. Culturally tailored public heath interventions focusing on the prevention and control of risk factors might ameliorate the CKD burden in this population.

Racial and Ethnic Variations in Mortality Rates for Patients Undergoing Maintenance Dialysis Treated in US Territories Compared with the US 50 States

BACKGROUND AND OBJECTIVES

In the United States mortality rates for patients treated with dialysis differ by racial and/or ethnic (racial/ethnic) group. Mortality outcomes for patients undergoing maintenance dialysis in the United States territories may differ from patients in the United States 50 states.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This retrospective cohort study of using US Renal Data System data included 1,547,438 adults with no prior transplantation and first dialysis treatment between April 1, 1995 and September 28, 2012. Cox proportional hazards regression was used to calculate hazard ratios (HRs) of death for the territories versus 50 states for each racial/ethnic group using the whole cohort and covariate-matched samples. Covariates included demographics, year of dialysis initiation, cause of kidney failure, comorbid conditions, dialysis modality, and many others.

RESULTS

Of 22,828 patients treated in the territories (American Samoa, Guam, Puerto Rico, Virgin Islands), 321 were white, 666 were black, 20,299 were Hispanic, and 1542 were Asian. Of 1,524,610 patients in the 50 states, 838,736 were white, 444,066 were black, 182,994 were Hispanic, and 58,814 were Asian. The crude mortality rate (deaths per 100 patient-years) was lower for whites in the territories than the 50 states (14 and 29, respectively), similar for blacks (18 and 17, respectively), higher for Hispanics (27 and 16, respectively), and higher for Asians (22 and 15). In matched analyses, greater risks of death remained for Hispanics (HR, 1.65; 95% confidence interval, 1.60 to 1.70; P<0.001) and Asians (HR, 2.01; 95% confidence interval, 1.78 to 2.27; P<0.001) living in the territories versus their matched 50 states counterparts. There were no significant differences in mortality among white or black patients in the territories versus the 50 states.

CONCLUSIONS

Mortality rates for patients undergoing dialysis in the United States territories differ substantially by race/ethnicity compared with the 50 states. After matched analyses for comparable age and risk factors, mortality risk no longer differed for whites or blacks, but remained much greater for territory-dwelling Hispanics and Asians.

Renal Function Decline in Latinos With Type 2 Diabetes

Introduction

Diabetic nephropathy remains a highly prevalent microvascular complication in individuals with type 2 diabetes mellitus (T2DM). Hispanic individuals are at increased risk of metabolic and cardiovascular complications compared with non-Hispanic white individuals. We described the long-term kidney outcomes using a culturally based approach to diabetes management in Hispanic patients implemented by the Joslin Diabetes Center’s Latino Diabetes Initiative.

Methods

Our retrospective study included 594 Hispanic patients evaluated at the Joslin Diabetes Center from July 2002 to July 2015. Demographic and clinical data were collected from the outpatient visits.

Results

Uncontrolled high blood pressure (hazard ratio [HR]: 1.72; 95% confidence interval [CI]:1.18–2.51; P = 0.005), overweight (HR: 2.68; 95% CI: 1.13–6.38; P = 0.026), and longstanding T2DM duration (HR: 1.11; 95% CI: 1.08–1.14; P < 0.0001) at baseline were significantly associated with increased risk of chronic kidney disease (CKD). Although poor glycemic control (HR: 1.18; 95% CI: 1.099–1.258; P < 0.0001), systolic blood pressure (SBP) >140 (HR: 1.01; 95% CI: 1.006–1.02; P = 0.0002), and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use (HR: 1.53; 95% CI: 1.03–2.29; P = 0.04) were significantly associated with increased CKD incidence during follow-up. Interestingly, statin use was associated with lower CKD incidence during the follow-up (HR: 0.52; 95% CI: 0.42–0.65; P < 0.0001). The annual rate of renal function decline in our cohort was estimated to be –1.39 ml/min per 1.73 m².

Conclusion

Renal function decline in Latinos is associated with expected but modifiable variables, such as uncontrolled diabetes, uncontrolled hypertension, and being overweight. However, the annual rate of renal function decline in our cohort was estimated to be comparatively higher than previous reports in Hispanic individuals without T2DM, and the general US population with T2DM, but lower than expected for this high-risk group. We highlight the importance of a culturally based patient-centered therapeutic approach to improve long-term outcomes in Hispanic patients at high risk of CKD.

Patient Experience with Primary Care Physician and Risk for Hospitalization in Hispanics with CKD

BACKGROUND AND OBJECTIVES

In the general population, the quality of the patient experience with their primary care physician may influence health outcomes but this has not been evaluated in CKD. This is relevant for the growing Hispanic CKD population, which potentially faces challenges to the quality of the patient experience related to language or cultural factors. We evaluated the association between the patient experience with their primary care physician and outcomes in Hispanics with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This prospective observational study included 252 English- and Spanish-speaking Hispanics with entry eGFR of 20-70 ml/min per 1.73 m2, enrolled in the Hispanic Chronic Renal Insufficiency Cohort study between 2005 and 2008. Patient experience with their primary care physician was assessed by the Ambulatory Care Experiences Survey subscales: communication quality, whole-person orientation, health promotion, interpersonal treatment, and trust. Poisson and proportional hazards models were used to assess the association between the patient experience and outcomes, which included hospitalization, ESKD, and all-cause death.

RESULTS

Participants had a mean age of 56 years, 38% were women, 80% were primary Spanish speakers, and had a mean eGFR of 38 ml/min per 1.73 m2. Over 4.8 years (median) follow-up, there were 619 hospitalizations, 103 ESKD events, and 56 deaths. As compared with higher subscale scores, lower scores on four of the five subscales were associated with a higher adjusted rate ratio (RR) for all-cause hospitalization (communication quality: RR, 1.54; 95% confidence interval [95% CI], 1.25 to 1.90; health promotion: RR, 1.31; 95% CI, 1.05 to 1.62; interpersonal treatment: RR, 1.50; 95% CI, 1.22 to 1.85; and trust: RR, 1.57; 95% CI, 1.27 to 1.93). There was no significant association of subscales with incident ESKD or all-cause death.

CONCLUSIONS

Lower perceived quality of the patient experience with their primary care physician was associated with a higher risk of hospitalization.

Sleep-Disordered Breathing and Prevalent Albuminuria in Hispanics/Latinos

Introduction

Although sleep-disordered breathing has been found to be associated with higher urine albumin excretion, this association has not been evaluated in Hispanic/Latino populations, which experience a high burden of end-stage renal disease compared with non-Hispanics. We evaluated the association of sleep-disordered breathing with prevalent albuminuria among US Hispanics/Latinos.

Methods

This was a cross-sectional study of baseline data from participants in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a population-based study that enrolled 16,415 adults in 4 US communities. Sleep-disordered breathing was assessed using a home sleep apnea monitor for overnight recording and was defined using 3 thresholds of the apnea−hypopnea index (AHI; 3% desaturation): ≥5, ≥15, and ≥30. Albuminuria was defined as a urine albumin-to-creatinine ratio of ≥30 mg/g.

Results

There were 12,572 participants with complete data available for analysis. The age- and sex-adjusted prevalence of albuminuria was 9.1%. Mean age was 41 years, and 48% were men. Age- and sex-adjusted prevalence of sleep-disordered breathing was higher among individuals with albuminuria compared with those without albuminuria (36% vs. 25% had AHI ≥5, 18% vs. 9% had AHI ≥15, and 9% vs. 4% had AHI ≥30). In multivariable logistic regression analyses, AHIs ≥5, ≥15, and ≥30 were associated with greater odds of albuminuria compared with those with AHIs <5, <15, and <30 (odds ratio [OR] 1.42, 95% confidence interval [CI]: 1.14−1.76; OR: 1.71, 95% CI: 1.33−2.20; and OR 1.93, 95% CI 1.34−2.79), respectively. This association varied by Hispanic/Latino background group.

Conclusion

In US Hispanic/Latinos, sleep-disordered breathing was independently associated with higher odds of prevalent albuminuria.

CKD and ESRD in US Hispanics

Hispanics are the largest racial/ethnic minority group in the United States, and they experience a substantial burden of kidney disease. Although the prevalence of chronic kidney disease (CKD) is similar or slightly lower in Hispanics than non-Hispanic whites, the age- and sex-adjusted prevalence rate of end-stage renal disease is almost 50% higher in Hispanics compared with non-Hispanic whites. This has been attributed in part to faster CKD progression among Hispanics. Furthermore, Hispanic ethnicity has been associated with a greater prevalence of cardiovascular disease risk factors, including obesity and diabetes, as well as CKD-related complications. Despite their less favorable socioeconomic status, which often leads to limited access to quality health care, and their high comorbid condition burden, the risk for mortality among Hispanics appears to be lower than for non-Hispanic whites. This survival paradox has been attributed to a complex interplay between sociocultural and psychosocial factors, as well as other factors. Future research should focus on evaluating the long-term impact of these factors on patient-centered and clinical outcomes. National policies are needed to improve access to and quality of health care among Hispanics with CKD.

Risk score for first-screening of prevalent undiagnosed chronic kidney disease in Peru: the CRONICAS-CKD risk score

BACKGROUND

Chronic Kidney Disease (CKD) represents a great burden for the patient and the health system, particularly if diagnosed at late stages. Consequently, tools to identify patients at high risk of having CKD are needed, particularly in limited-resources settings where laboratory facilities are scarce. This study aimed to develop a risk score for prevalent undiagnosed CKD using data from four settings in Peru: a complete risk score including all associated risk factors and another excluding laboratory-based variables.

METHODS

Cross-sectional study. We used two population-based studies: one for developing and internal validation (CRONICAS), and another (PREVENCION) for external validation. Risk factors included clinical- and laboratory-based variables, among others: sex, age, hypertension and obesity; and lipid profile, anemia and glucose metabolism. The outcome was undiagnosed CKD: eGFR < 60 ml/min/1.73m². We tested the performance of the risk scores using the area under the receiver operating characteristic (ROC) curve, sensitivity, specificity, positive/negative predictive values and positive/negative likelihood ratios.

RESULTS

Participants in both studies averaged 57.7 years old, and over 50% were females. Age, hypertension and anemia were strongly associated with undiagnosed CKD. In the external validation, at a cut-off point of 2, the complete and laboratory-free risk scores performed similarly well with a ROC area of 76.2% and 76.0%, respectively (P = 0.784). The best assessment parameter of these risk scores was their negative predictive value: 99.1% and 99.0% for the complete and laboratory-free, respectively.

CONCLUSIONS

The developed risk scores showed a moderate performance as a screening test. People with a score of ≥ 2 points should undergo further testing to rule out CKD. Using the laboratory-free risk score is a practical approach in developing countries where laboratories are not readily available and undiagnosed CKD has significant morbidity and mortality.

Under-diagnosed chronic kidney disease in Jordanian adults: prevalence and correlates

BACKGROUND

Jordan has no relevant database or registry by which chronic kidney disease (CKD) would be early identified. The purpose of the present study is to uncover the prevalence of CKD in a national sample of Jordanian patients at high risk and examine the association of CKD with demographic and clinical factors.

METHODS

This is a cross-sectional, correlational study that involved 540 outpatients at high risk for CKD. Demographic and clinical data were obtained in the period from September 2013 to March 2014. Prevalence of CKD was defined based on the National Kidney Foundation Kidney Disease Outcomes Quality Initiative Classification of CKD using estimated glomerular filtration rate. Associations of CKD and demographic and clinical factors were examined using bivariate analysis.

RESULTS

The majority of the sample were females (64%), their mean age (±SD) was 55.0 ± 12.5 years, their mean eGFR (±SD) was 116.0 ± 47.5. One third of patients had eGFR of 23.5%, 5.4%, 0.7% and 0.7% which corresponds with mild, moderate, severe and very severe reduction in eGFR, respectively. Ageing, being male, unemployment, packs/years of smoking, co-morbidities [hypertension (HTN), diabetes mellitus (DM) and cardiovascular disease] and low high density lipoprotein (HDL) correlated positively with development of CKD.

CONCLUSION

This study demonstrates a high rate of under-diagnosed CKD among Jordanians. Several demographic and clinical factors are linked with the development of CKD. Policymakers and healthcare providers need to establish an evidence-based practice project to prevent and screen for CKD in Jordan.

Association of Albuminuria With Cardiac Dysfunction in US Hispanics/Latinos

Higher urine albumin-to-creatinine ratio (UACR) has been associated with cardiac dysfunction in the general population. We assessed the association of UACR with cardiac structure and function in the Echocardiographic Study of Latinos (Echo-SOL), an ancillary study of the Hispanic Community Health Study/Study of Latinos across 4 US sites. Echo-SOL participants underwent standard 2-dimensional echocardiography, including speckle-tracking strain analysis. UACR was categorized as normal and high-normal (based on the midpoint of values below microalbuminuria), microalbuminuria (≥17 mg/g for men; ≥25 mg/g for women), and macroalbuminuria (≥250 mg/g; ≥355 mg/g). Simultaneous assessments were made of left ventricular (LV) mass index and hypertrophy and measures of LV systolic and diastolic dysfunction. We assessed the association of UACR with subclinical cardiac measures, adjusting for sociodemographic and cardiometabolic factors. Among 1,815 participants (median age 54, women 65%), 42% had normal UACR, 43% high-normal UACR, 13% microalbuminuria, and 2% macroalbuminuria. Prevalence of LV hypertrophy was 13%, LV systolic dysfunction (ejection fraction <50%) 3%, and diastolic dysfunction 53%. After covariate adjustment, both micro- and macroalbuminuria were significantly associated with a twofold increase in LV hypertrophy. Microalbuminuria but not macroalbuminuria was associated with worse global longitudinal strain. Elevated UACR, even at high-normal levels, was significantly associated with greater diastolic dysfunction. In conclusion, elevated UACR was associated with LV hypertrophy and diastolic dysfunction in the largest known population sample of US Hispanic/Latinos. Screening and detection of even high-normal UACR could be of value to guide cardiovascular disease prevention efforts among Hispanic/Latino Americans.

Smoking intensity and duration is associated with cardiac structure and function: the ECHOcardiographic Study of Hispanics/Latinos

Objective

Cardiovascular disease is the leading cause of death in smokers and this relationship is complicated by the multiplicity of cardiovascular effects of smoking. However, the relationship between intensity and duration of cigarette smoking and echocardiographic measures of right and left ventricular structure and function has been poorly studied.

Methods

We examined ECHO-SOL (Echocardiographic Study of Hispanics/Latinos) participants, a subset of the Hispanic Community Health Study/Study of Latinos. Participants were administered a detailed tobacco exposure questionnaire and a comprehensive echocardiography exam. Multivariable linear regression models (adjusted for age, sex, obesity, hypertension and diabetes statuses) were performed using sampling weights. Statistical significance was defined at p<0.01.

Results

There were 1818 ECHO-SOL participants (57.4% women, mean age 56.4 years). Among current smokers (n=304), increased duration of smoking, as measured by a younger age of smoking initiation, was significantly associated with higher mean left ventricular mass (LVM) and lower right ventricular (RV) function (lower right ventricular stroke volumes). More cigarettes smoked per day was significantly associated with higher mean LVM, worse diastolic function (higher E/e′ ratio), worse LV geometry (increased relative wall thickness) and worse RV function (decreasing right ventricular stroke volume). Among current smokers, higher mean lifetime pack-years (a combined measure of smoking intensity and duration) was associated with higher LVM, worse LV geometry, worse diastolic function, greater RV dilatation and worse RV function.

Conclusions

There is a dose–response relationship between intensity and duration of cigarette tobacco smoking with unfavourable changes of multiple measures of right-sided and left-sided cardiac structure and function.

Trends in the levels of urine and serum creatinine: data from NHANES 2001-2014

Data from the National Health and Nutrition Examination Survey were used to study trends for urine and serum creatinine over 2001-2014 for those aged ≥20 years. In the absence of chronic kidney disease, levels of urine creatinine decreased for the total population, for those aged 20-29, 50-59, and ≥70 years, for males, and for Mexican Americans and other race/ethnicities. Levels of serum cotinine also exhibited a decreasing trend over 2001-2014 for the total population, for those aged 20-29 and 40-49 years, for females, and for non-Hispanic whites and Mexican Americans. In general, levels of serum creatinine and urine creatinine were positively correlated for chronic kidney disease stages 1-3 and negatively correlated for chronic kidney disease stages 4 and 5.

Admixture Mapping Identifies an Amerindian Ancestry Locus Associated with Albuminuria in Hispanics in the United States

Increased urine albumin excretion is highly prevalent in Hispanics/Latinos. Previous studies have found an association between urine albumin excretion and Amerindian ancestry in Hispanic/Latino populations. Admixture between racial/ethnic groups creates long-range linkage disequilibrium between variants with different allelic frequencies in the founding populations and it can be used to localize genes. Hispanic/Latino genomes are an admixture of European, African, and Amerindian ancestries. We leveraged this admixture to identify associations between urine albumin excretion (urine albumin-to-creatinine ratio [UACR]) and genomic regions harboring variants with highly differentiated allele frequencies among the ancestral populations. Admixture mapping analysis of 12,212 Hispanic Community Health Study/Study of Latinos participants, using a linear mixed model, identified three novel genome-wide significant signals on chromosomes 2, 11, and 16. The admixture mapping signal identified on chromosome 2, spanning q11.2-14.1 and not previously reported for UACR, is driven by a difference between Amerindian ancestry and the other two ancestries (P<5.7 × 10^-5). Within this locus, two common variants located at the proapoptotic BCL2L11 gene associated with UACR: rs116907128 (allele frequency =0.14; P=1.5 × 10^-7) and rs586283 (C allele frequency =0.35; P=4.2 × 10^-7). In a secondary analysis, rs116907128 accounted for most of the admixture mapping signal observed in the region. The rs116907128 variant is common among full-heritage Pima Indians (A allele frequency =0.54) but is monomorphic in the 1000 Genomes European and African populations. In a replication analysis using a sample of full-heritage Pima Indians, rs116907128 significantly associated with UACR (P=0.01; n=1568). Our findings provide evidence for the presence of Amerindian-specific variants influencing the variation of urine albumin excretion in Hispanics/Latinos.

African Ancestry-Specific Alleles and Kidney Disease Risk in Hispanics/Latinos

African ancestry alleles may contribute to CKD among Hispanics/Latinos, but whether associations differ by Hispanic/Latino background remains unknown. We examined the association of CKD measures with African ancestry-specific APOL1 alleles that were directly genotyped and sickle cell trait (hemoglobin subunit β gene [HBB] variant) on the basis of imputation in 12,226 adult Hispanics/Latinos grouped according to Caribbean or Mainland background. We also performed an unbiased genome-wide association scan of urine albumin-to-creatinine ratios. Overall, 41.4% of participants were male, 44.6% of participants had a Caribbean background, and the mean age of all participants was 46.1 years. The Caribbean background group, compared with the Mainland background group, had a higher frequency of two APOL1 alleles (1.0% versus 0.1%) and the HBB variant (2.0% versus 0.7%). In the Caribbean background group, presence of APOL1 alleles (2 versus 0/1 copies) or the HBB variant (1 versus 0 copies) were significantly associated with albuminuria (odds ratio [OR], 3.2; 95% confidence interval [95% CI], 1.7 to 6.1; and OR, 2.6; 95% CI, 1.8 to 3.8, respectively) and albuminuria and/or eGFR<60 ml/min per 1.73 m² (OR, 2.9; 95% CI, 1.5 to 5.4; and OR, 2.4; 95% CI, 1.7 to 3.5, respectively). The urine albumin-to-creatinine ratio genome-wide association scan identified associations with the HBB variant among all participants, with the strongest association in the Caribbean background group (P=3.1×10^-10 versus P=9.3×10^-3 for the Mainland background group). In conclusion, African-specific alleles associate with CKD in Hispanics/Latinos, but allele frequency varies by Hispanic/Latino background/ancestry.

IDENTIFYING PROBABLE DIABETES MELLITUS AMONG HISPANICS/LATINOS FROM FOUR U.S. CITIES: FINDINGS FROM THE HISPANIC COMMUNITY HEALTH STUDY/STUDY OF LATINOS

OBJECTIVE

The aim of this study was to compare the ability of American Diabetes Association (ADA) diagnostic criteria to identify U.S. Hispanics/Latinos from diverse heritage groups with probable diabetes mellitus and assess cardiovascular risk factor correlates of those criteria.

METHODS

Cross-sectional analysis of data from 15,507 adults from 6 Hispanic/Latino heritage groups, enrolled in the Hispanic Community Health Study/Study of Latinos. The prevalence of probable diabetes mellitus was estimated using individual or combinations of ADA-defined cut points. The sensitivity and specificity of these criteria at identifying diabetes mellitus from ADA-defined prediabetes and normoglycemia were evaluated. Prevalence ratios of hypertension, abnormal lipids, and elevated urinary albumin-creatinine ratio for unrecognized diabetes mellitus-versus prediabetes and normoglycemia-were calculated.

RESULTS

Among Hispanics/Latinos (mean age, 43 years) with diabetes mellitus, 39.4% met laboratory test criteria for probable diabetes, and the prevalence varied by heritage group. Using the oral glucose tolerance test as the gold standard, the sensitivity of fasting plasma glucose (FPG) and hemoglobin A1c-alone or in combination-was low (18, 23, and 33%, respectively) at identifying probable diabetes mellitus. Individuals who met any criterion for probable diabetes mellitus had significantly higher (P<.05) prevalence of most cardiovascular risk factors than those with normoglycemia or prediabetes, and this association was not modified by Hispanic/Latino heritage group.

CONCLUSION

FPG and hemoglobin A1c are not sensitive (but are highly specific) at detecting probable diabetes mellitus among Hispanics/Latinos, independent of heritage group. Assessing cardiovascular risk factors at diagnosis might prompt multitarget interventions and reduce health complications in this young population.

ABBREVIATIONS

2hPG = 2-hour post-glucose load plasma glucose ADA = American Diabetes Association BMI = body mass index CV = cardiovascular FPG = fasting plasma glucose HbA1c = hemoglobin A1c HCHS/SOL = Hispanic Community Health Study/Study of Latinos HDL-C = high-density-lipoprotein cholesterol NGT = normal glucose tolerance NHANES = National Health and Nutrition Examination Survey OGTT = oral glucose tolerance test TG = triglyceride UACR = urine albumin-creatinine ratio.

Race/Ethnicity and Cardiovascular Outcomes in Adults With CKD: Findings From the CRIC (Chronic Renal Insufficiency Cohort) and Hispanic CRIC Studies

BACKGROUND

Non-Hispanic blacks and Hispanics with end-stage renal disease have a lower risk for death than non-Hispanic whites, but data for racial/ethnic variation in cardiovascular outcomes for non-dialysis-dependent chronic kidney disease are limited.

STUDY DESIGN

Prospective cohort.

SETTING & PARTICIPANTS

3,785 adults with entry estimated glomerular filtration rates of 20 to 70mL/min/1.73m(2) enrolled in the CRIC (Chronic Renal Insufficiency Cohort) Study.

PREDICTORS

Race/ethnicity (non-Hispanic white, non-Hispanic black, and Hispanic).

OUTCOMES

Cardiovascular outcomes (atherosclerotic events [myocardial infarction, stroke, or peripheral arterial disease] and heart failure) and a composite of each cardiovascular outcome or all-cause death.

MEASUREMENTS

Multivariable Cox proportional hazards.

RESULTS

During a median follow-up of 6.6 years, we observed 506 atherosclerotic events, 551 heart failure events, and 692 deaths. In regression analyses, there were no significant differences in atherosclerotic events among the 3 racial/ethnic groups. In analyses stratified by clinical site, non-Hispanic blacks had a higher risk for heart failure events (HR, 1.59; 95% CI, 1.29-1.95), which became nonsignificant after adjustment for demographic factors and baseline kidney function. In contrast, Hispanics had similar risk for heart failure events as non-Hispanic whites. In analyses stratified by clinical site, compared with non-Hispanic whites, non-Hispanic blacks were at similar risk for atherosclerotic events or death. However, after further adjustment for cardiovascular risk factors, medications, and mineral metabolism markers, non-Hispanic blacks had 17% lower risk for the outcome (HR, 0.83; 95% CI, 0.69-0.99) than non-Hispanic whites, whereas there was no significant association with Hispanic ethnicity.

LIMITATIONS

Hispanics were largely recruited from a single center, and the study was underpowered to evaluate the association between Hispanic ethnicity and mortality.

CONCLUSIONS

There were no significant racial/ethnic differences in adjusted risk for atherosclerotic or heart failure outcomes. Future research is needed to better explain the reduced risk for atherosclerotic events or death in non-Hispanic blacks compared with non-Hispanic whites.

An Age-Calibrated Definition of Chronic Kidney Disease: Rationale and Benefits

Defining chronic kidney disease (CKD) is the subject of intense debate in the current nephrology literature. The debate concerns the threshold value of estimated glomerular filtration rate (eGFR) used to make the diagnosis of CKD. Current recommendations argue that a universal threshold of 60 mL/min/1.73m(2) should be used. This threshold has been defended by epidemiological studies showing that the risk of mortality or end-stage renal disease increases with an eGFR below 60 mL/min/1.73m(2). However, a universal threshold does not take into account the physiologic decline in GFR with ageing nor does it account for the risk of mortality and end-stage renal disease being trivial with isolated eGFR levels just below 60 mL/min/1.73m(2) in older subjects and significantly increased with eGFR levels just above 60 mL/min/1.73m(2) among younger patients. Overestimation of the CKD prevalence in the elderly (medicalisation of senescence) and underestimation of CKD (potentially from treatable primary nephrologic diseases) in younger patients is of primary concern. An age-calibrated definition of CKD has been proposed to distinguish age-related from disease-related changes in eGFR. For patients younger than 40 years, CKD is defined by eGFR below 75 mL/min/1.73m(2). For patients with ages between 40 and 65 years, CKD is defined by 60 mL/min/1.73m(2). For subjects older than 65 years without albuminuria or proteinuria, CKD is defined by eGFR below 45 mL/min/1.73m(2).