Genomics in nephrology: identifying informatics opportunities to improve diagnosis of genetic kidney disorders using a human-centered design approach

BACKGROUND

Genomic kidney conditions often have a long lag between onset of symptoms and diagnosis. To design a real time genetic diagnosis process that meets the needs of nephrologists, we need to understand the current state, barriers, and facilitators nephrologists and other clinicians who treat kidney conditions experience, and identify areas of opportunity for improvement and innovation.

METHODS

Qualitative in-depth interviews were conducted with nephrologists and internists from 7 health systems. Rapid analysis identified themes in the interviews. These were used to develop service blueprints and process maps depicting the current state of genetic diagnosis of kidney disease.

RESULTS

Themes from the interviews included the importance of trustworthy resources, guidance on how to order tests, and clarity on what to do with results. Barriers included lack of knowledge, lack of access, and complexity surrounding the case and disease. Facilitators included good user experience, straightforward diagnoses, and support from colleagues.

DISCUSSION

The current state of diagnosis of kidney diseases with genetic etiology is suboptimal, with information gaps, complexity of genetic testing processes, and heterogeneity of disease impeding efficiency and leading to poor outcomes. This study highlights opportunities for improvement and innovation to address these barriers and empower nephrologists and other clinicians who treat kidney conditions to access and use real time genetic information.

Development and Validation of the American Heart Association's PREVENT Equations

BACKGROUND

Multivariable equations are recommended by primary prevention guidelines to assess absolute risk of cardiovascular disease (CVD). However, current equations have several limitations. Therefore, we developed and validated the American Heart Association Predicting Risk of CVD EVENTs (PREVENT) equations among US adults 30 to 79 years of age without known CVD.

METHODS

The derivation sample included individual-level participant data from 25 data sets (N=3 281 919) between 1992 and 2017. The primary outcome was CVD (atherosclerotic CVD and heart failure). Predictors included traditional risk factors (smoking status, systolic blood pressure, cholesterol, antihypertensive or statin use, and diabetes) and estimated glomerular filtration rate. Models were sex-specific, race-free, developed on the age scale, and adjusted for competing risk of non-CVD death. Analyses were conducted in each data set and meta-analyzed. Discrimination was assessed using the Harrell C-statistic. Calibration was calculated as the slope of the observed versus predicted risk by decile. Additional equations to predict each CVD subtype (atherosclerotic CVD and heart failure) and include optional predictors (urine albumin-to-creatinine ratio and hemoglobin A1c), and social deprivation index were also developed. External validation was performed in 3 330 085 participants from 21 additional data sets.

RESULTS

Among 6 612 004 adults included, mean±SD age was 53±12 years, and 56% were women. Over a mean±SD follow-up of 4.8±3.1 years, there were 211 515 incident total CVD events. The median C-statistics in external validation for CVD were 0.794 (interquartile interval, 0.763-0.809) in female and 0.757 (0.727-0.778) in male participants. The calibration slopes were 1.03 (interquartile interval, 0.81-1.16) and 0.94 (0.81-1.13) among female and male participants, respectively. Similar estimates for discrimination and calibration were observed for atherosclerotic CVD- and heart failure-specific models. The improvement in discrimination was small but statistically significant when urine albumin-to-creatinine ratio, hemoglobin A1c, and social deprivation index were added together to the base model to total CVD (ΔC-statistic [interquartile interval] 0.004 [0.004-0.005] and 0.005 [0.004-0.007] among female and male participants, respectively). Calibration improved significantly when the urine albumin-to-creatinine ratio was added to the base model among those with marked albuminuria (>300 mg/g; 1.05 [0.84-1.20] versus 1.39 [1.14-1.65]; P=0.01).

CONCLUSIONS

PREVENT equations accurately and precisely predicted risk for incident CVD and CVD subtypes in a large, diverse, and contemporary sample of US adults by using routinely available clinical variables.

Glucagon-like peptide-1 receptor agonists and the risk of atrial fibrillation in adults with diabetes: a real-world study

BACKGROUND

Glucagon-like peptide-1 receptor agonists (GLP-1RA) have cardiovascular benefits in type 2 diabetes, but none of the cardiovascular trials studied atrial fibrillation/atrial flutter (AF) as a primary endpoint. Data from post-marketing surveillance studies remains sparse.

OBJECTIVE

To examine the real-world risk of AF comparing GLP-1RA with other non-insulin glucose-lowering agents.

DESIGN

Cohort study using de-identified electronic health record data from the Optum Labs Data Warehouse.

PARTICIPANTS

Adult patients with diabetes who were newly prescribed add-on non-insulin glucose-lowering agents and were on metformin between 2005-2020.

EXPOSURES

New users of GLP-1RA were separately compared with new users of dipeptidyl peptidase-4 inhibitors (DPP4i) and sodium-glucose cotransporter 2 inhibitors (SGLT2i), using 1:1 propensity score matching to adjust for differences in patient characteristics.

MAIN MEASURES

The primary outcome was incident AF, defined and captured by diagnosis code for AF. Incidence rate difference (IRD) and hazard ratio (HR) were estimated in the matched cohorts.

KEY RESULTS

In the matched cohort of 14,566 pairs of GLP-1RA and DPP4i followed for a median of 3.8 years, GLP-1RA use was associated with a lower risk of AF (IRD, -1.0; 95% CI, -1.8 to -0.2 per 1000 person-years; HR, 0.82; 95% CI, 0.70 to 0.96). In the matched cohort of 9,424 pairs of patients on GLP-1RA and SGLT2i with a median follow-up of 2.9 years, there was no difference in the risk for AF (IRD, 0.4; 95% CI -0.7 to 1.5 per 1000 person-years; HR, 1.12; 95% CI, 0.89 to 1.42).

CONCLUSIONS

In this real-word study, GLP-1RA was associated with a lower risk of AF compared with DPP4i, but no difference compared with SGLT2i, suggesting that cardiovascular benefits of GLP-1RA use may extend to prevention for AF in patients with diabetes. Our findings call for future randomized controlled trials to focus on the effects of GLP-1RA on AF prevention.

Blockbuster Medications for Obesity: A Primer for Nephrologists

The prevalence of obesity in the United States and across the world continues to climb, imparting increased risk of chronic disease. This impact is doubly felt in nephrology because obesity not only increases the risk of chronic kidney disease (CKD) but also exacerbates existing cardiovascular morbidity and mortality. The role of medical weight loss therapy in CKD has been debated, but increasing evidence suggests that intentional weight loss is protective against adverse kidney and cardiovascular outcomes. This may be particularly true with the advent of novel pharmacotherapies taking advantage of the incretin system, resulting in weight loss approaching that seen with surgical interventions. Moreover, these novel therapies have repeatedly demonstrated protective effects on the cardiovascular system. Here, we review the impact of obesity and weight loss on CKD, and the biological basis and clinical evidence for incretin therapy. This perspective provides recommended prescribing practices as a practical tool to engage nephrologists and patients with CKD in the treatment of obesity-related morbidity.

GWAS for the composite traits of hematuria and albuminuria

Our GWAS of hematuria in the UK Biobank identified 6 loci, some of which overlap with loci for albuminuria suggesting pleiotropy. Since clinical syndromes are often defined by combinations of traits, generating a combined phenotype can improve power to detect loci influencing multiple characteristics. Thus the composite trait of hematuria and albuminuria was chosen to enrich for glomerular pathologies. Cases had both hematuria defined by ICD codes and albuminuria defined as uACR > 3 mg/mmol. Controls had neither an ICD code for hematuria nor an uACR > 3 mg/mmol. 2429 cases and 343,509 controls from the UK Biobank were included. eGFR was lower in cases compared to controls, with the exception of the comparison in females using CKD-EPI after age adjustment. Variants at 4 loci met genome-wide significance with the following nearest genes: COL4A4, TRIM27, ETV1 and CUBN. TRIM27 is part of the extended MHC locus. All loci with the exception of ETV1 were replicated in the Geisinger MyCode cohort. The previous GWAS of hematuria reported COL4A3-COL4A4 variants and HLA-B*0801 within MHC, which is in linkage disequilibrium with the TRIM27 variant (D' = 0.59). TRIM27 is highly expressed in the tubules. Additional loci included a coding sequence variant in CUBN (p.Ala2914Val, MAF = 0.014 (A), p = 3.29E-8, OR = 2.09, 95% CI = 1.61-2.72). Overall, GWAS for the composite trait of hematuria and albuminuria identified 4 loci, 2 of which were not previously identified in a GWAS of hematuria.

The Phenotypic Spectrum of COL4A3 Heterozygotes

Introduction

The penetrance and phenotypic spectrum of autosomal dominant Alport Syndrome (ADAS), affecting 1 in 106, remains understudied.

Methods

Using data from 174,418 participants in the Geisinger MyCode/DiscovEHR study, an unselected health system-based cohort with whole exome sequencing, we identified 403 participants who were heterozygous for likely pathogenic COL4A3 variants. Phenotypic data was evaluated using International Classification of Diseases (ICD) codes, laboratory data, and chart review. To evaluate the phenotypic spectrum of genetically-determined ADAS, we matched COL4A3 heterozygotes 1:5 to nonheterozygotes using propensity scores by demographics, hypertension, diabetes, and nephrolithiasis.

Results

COL4A3 heterozygotes were at significantly increased risks of hematuria, decreased estimated glomerular filtration rate (eGFR), albuminuria, and kidney failure (P < 0.05 for all comparisons) but not bilateral sensorineural hearing loss (P = 0.9). Phenotypic severity was more severe for collagenous domain glycine missense variants than protein truncating variants (PTVs). For example, patients with Gly695Arg (n = 161) had markedly increased risk of dipstick hematuria (odds ratio [OR] 9.50; 95% confidence interval [CI]: 6.32, 14.28) and kidney failure (OR 7.02; 95% CI: 3.48, 14.16) whereas those with PTVs (n = 119) had moderately increased risks of dipstick hematuria (OR 1.64; 95% CI: 1.03, 2.59) and kidney failure (OR 3.44; 95% CI: 1.28, 9.22). Less than a third of patients had albuminuria screening completed, and fewer than 1 of 3 were taking inhibitors of the renin-angiotensin-aldosterone system.

Conclusion

This study demonstrates a wide spectrum of phenotypic severity in ADAS due to COL4A3 with phenotypic variability by genotype. Future studies are needed to evaluate the impact of earlier diagnosis, appropriate evaluation, and treatment of ADAS.

Association between the diagnostic classification of newly diagnosed coronary artery disease and future heart failure development

OBJECTIVE

The first clinical manifestation of coronary artery disease (CAD) varies widely from unheralded myocardial infarction (MI) to mild, incidentally detected disease. The primary objective of this study was to quantify the association between different initial CAD diagnostic classifications and future heart failure.

METHODS

This retrospective study incorporated the electronic health record of a single integrated health care system. Newly diagnosed CAD was classified into a mutually exclusive hierarchy as MI, CAD with coronary artery bypass graft (CABG), CAD with percutaneous coronary intervention, CAD only, unstable angina, and stable angina. An acute CAD presentation was defined when the diagnosis was associated with a hospital admission. New heart failure was identified after the CAD diagnosis.

RESULTS

Among 28 693 newly diagnosed CAD patients, initial presentation was acute in 47% and manifested as MI in 26%. Within 30 days of CAD diagnosis, MI [hazard ratio (HR) = 5.1; 95% confidence interval: 4.1-6.5] and unstable angina (3.2; 2.4-4.4) classifications were associated with the highest heart failure risk (compared to stable angina), as was acute presentation (2.9; 2.7-3.2). Among stable, heart failure-free CAD patients followed on average 7.4 years, initial MI (adjusted HR = 1.6; 1.4-1.7) and CAD with CABG (1.5; 1.2-1.8) were associated with higher long-term heart failure risk, but an initial acute presentation was not (1.0; 0.9-1.0).

CONCLUSION

Nearly 50% of initial CAD diagnoses are associated with hospitalization, and these patients are at high risk of early heart failure. Among stable CAD patients, MI remained the diagnostic classification associated with the highest long-term heart failure risk, however, having an initial acute CAD presentation was not associated with long-term heart failure.

Racial Differences and Contributory Cardiovascular and Non-Cardiovascular Risk Factors Towards Chronic Kidney Disease Progression

Background

The prevalence of advanced chronic kidney disease (CKD) is higher in Black than in White Americans. We evaluated CKD progression in Black and White participants and the contribution of biological risk factors. We included the study of lung function (measured by forced vital capacity [FVC]), which is part of the emerging notion of interorgan cross-talk with the kidneys to racial differences in CKD progression.

Methods

This longitudinal study included 2175 Black and 2207 White adult Coronary Artery Risk Development in Young Adults (CARDIA) participants. Estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (UACR) were measured at study year 10 (age 27-41y) and every five years for 20 years. The outcome was CKD progression through no CKD, low, moderate, high, or very high-risk categories based on eGFR and UACR in combination. The association between race and CKD progression as well as the contribution of risk factors to racial differences were assessed in multivariable-adjusted Cox models.

Results

Black participants had higher CKD transition probabilities than White participants and more prevalent risk factors during the 20-year period studied. Hazard ratios for CKD transition for Black (vs White participants) were 1.38 from No CKD into ≥ low risk, 2.25 from ≤ low risk into ≥ moderate risk, and 4.49 from ≤ moderate risk into ≥ high risk. Racial differences in CKD progression from No CKD into ≥ low risk were primarily explained by FVC (54.8%), hypertension (30.9%), and obesity (20.8%). In contrast, racial differences were less explained in more severe transitions.

Conclusion

Black participants had a higher risk of CKD progression, and this discrepancy may be partly explained by FVC and conventional risk factors.

The Phenotypic Spectrum of COL4A3 Heterozygotes

Most data on Alport Syndrome (AS) due to COL4A3 are limited to families with autosomal recessive AS or severe manifestations such as focal segmental glomerulosclerosis (FSGS). Using data from 174,418 participants in the Geisinger MyCode/DiscovEHR study, an unselected health system-based cohort with whole exome sequencing, we identified 403 participants (0.2%) who were heterozygous for likely pathogenic COL4A3 variants. Phenotypic data was evaluated using International Classification of Diseases (ICD) codes, laboratory data, and chart review. To evaluate the phenotypic spectrum of genetically-determined autosomal dominant AS, we matched COL4A3 heterozygotes 1:5 to non-heterozygotes using propensity scores by demographics, hypertension, diabetes, and nephrolithiasis. COL4A3 heterozygotes were at significantly increased risks of hematuria, decreased estimated glomerular filtration rate (eGFR), albuminuria, and end-stage kidney disease (ESKD) (p<0.05 for all comparisons) but not bilateral sensorineural hearing loss (p=0.9). Phenotypic severity tended to be more severe among patients with glycine missense variants located within the collagenous domain. For example, patients with Gly695Arg (n=161) had markedly increased risk of dipstick hematuria (OR 9.47, 95% CI: 6.30, 14.22) and ESKD diagnosis (OR 7.01, 95% CI: 3.48, 14.12) whereas those with PTVs (n=119) had moderately increased risks of dipstick hematuria (OR 1.63, 95% CI: 1.03, 2.58) and ESKD diagnosis (OR 3.43, 95% CI: 1.28, 9.19). Less than a third of patients had albuminuria screening completed, and fewer than 1/3 were taking inhibitors of the renin-angiotensin-aldosterone system (RAASi). Future studies are needed to evaluate the impact of earlier diagnosis, appropriate evaluation, and treatment of ADAS.

Nontraditional Risk Factors for Progression Through Chronic Kidney Disease Risk Categories: The Coronary Artery Risk Development in Young Adults Study

BACKGROUND

There may be nontraditional pathways of chronic kidney disease (CKD) progression that are complementary to classical pathways. Therefore, we aimed to examine nontraditional risk factors for incident CKD and its progression.

METHODS

We used the generally healthy population (n = 4382) starting at age 27-41 years in the Coronary Artery Risk Development in Young Adults (CARDIA) cohort, which is an observational longitudinal study. Nontraditional risk factors included forced vital capacity, inflammation, serum urate, and serum carotenoids. CKD risk category was classified using the estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (UACR) measured in 1995-1996 and repeated every 5 years for 20 years: No CKD, low risk, moderate risk, high risk, and very high risk.

RESULTS

At baseline, 84.8% had no CKD (eGFR ≥60 mL/min/1.73 m2 and UACR <10 mg/g), 10.3% were in the low risk (eGFR ≥60 and UACR 10-29), and 4.9% had CKD (eGFR <60 and/or UACR ≥ 30). Nontraditional risk factors were significantly associated with the progression of CKD to higher categories. Hazard ratios per standard deviation of the predictor for incident CKD and its progression from the No CKD and low and moderate risk into CKD were inverse for forced vital capacity and serum carotenoids and positive for serum urate, GlycA, and C-reactive protein, the first 3 even after adjustment for conventional risk factors.

CONCLUSION

Several nontraditional markers were significantly associated with an increased risk of progression to higher CKD categories in generally healthy young to middle-aged adults.

Individuals heterozygous for ALG8 protein-truncating variants are at increased risk of a mild cystic kidney disease

ALG8 protein-truncating variants (PTVs) have previously been described in patients with polycystic liver disease and in some cases cystic kidney disease. Given a lack of well-controlled studies, we determined whether individuals heterozygous for ALG8 PTVs are at increased risk of cystic kidney disease in a large, unselected health system-based observational cohort linked to electronic health records in Pennsylvania (Geisinger-Regeneron DiscovEHR MyCode study). Out of 174,172 patients, 236 were identified with ALG8 PTVs. Using ICD-based outcomes, patients with these variants were significantly at increased risk of having any kidney/liver cyst diagnosis (Odds Ratio 2.42, 95% confidence interval: 1.53-3.85), cystic kidney disease (3.03, 1.26-7.31), and nephrolithiasis (1.89, 1.96-2.97). To confirm this finding, blinded radiology review of computed tomography and magnetic resonance imaging studies was completed in a matched cohort of 52 thirty-plus year old ALG8 PTV heterozygotes and related non-heterozygotes. ALG8 PTV heterozygotes were significantly more likely to have cystic kidney disease, defined as four or more kidney cysts (57.7% vs. 7.7%), or bilateral kidney cysts (69.2% vs. 15.4%), but not one or more liver cyst (11.5% vs. 7.7%). In publicly available UK Biobank data, ALG8 PTV heterozygotes were at significantly increased risk of ICD code N28 (other disorders of kidney/ureter) (3.85% vs. 1.33%). ALG8 PTVs were not associated with chronic kidney disease or kidney failure in the MyCode study or the UK Biobank data. Thus, PTVs in ALG8 result in increased risk of a mild cystic kidney disease phenotype.

A National Registry for People With All Stages of Kidney Disease: The National Kidney Foundation (NKF) Patient Network

RATIONALE & OBJECTIVE

The National Kidney Foundation (NKF) launched the first national US kidney disease patient registry, the NKF Patient Network, that is open to patients throughout the continuum of chronic kidney disease (CKD). The Network provides individualized education and will facilitate patient-centered research, clinical care, and health policy decisions. Here, we present the overall design and the results of a feasibility study that was conducted July through December 2020.

STUDY DESIGN

Longitudinal observational cohort study of patient-entered data with or without electronic health care record (EHR) linkage in collaboration with health systems.

SETTING & PARTICIPANTS

People with CKD, age≥18 years, are invited through their provider, NKF communications, or national outreach campaign. People self-enroll and share their data through a secure portal that offers individualized education and support. The first health system partner is Geisinger.

EXPOSURE

Any cause and stage of CKD, including dialysis and kidney transplant recipients.

OUTCOME

Feasibility of the EHR data transfer, participants' characteristics, and their perspectives on usability and content.

ANALYTICAL APPROACH

Data were collected and analyzed through the registry portal powered by the Pulse Infoframe healthie 2.0 platform.

RESULTS

During the feasibility study, 80 participants completed their profile, and 42 completed a satisfaction survey. Mean age was 57.5 years, 51% were women, 83% were White, and 89% were non-Hispanic or Latino. Of the participants, 60% were not aware of their level of estimated glomerular filtration rate and 91% of their urinary albumin-creatinine ratio.

LIMITATIONS

Challenges for the Network are lack of awareness of kidney disease for many with CKD, difficulty in recruiting vulnerable populations or those with low digital readiness, and loss to follow-up, all leading to selection bias.

CONCLUSIONS

The Network is positioned to become a national and international platform for real-world data that can inform the development of patient-centered research, care, and treatments.

Exome Sequencing of a Clinical Population for Autosomal Dominant Polycystic Kidney Disease

IMPORTANCE

Most studies of autosomal dominant polycystic kidney disease (ADPKD) genetics have used kidney specialty cohorts, focusing on PKD1 and PKD2. These can lead to biased estimates of population prevalence of ADPKD-associated gene variants and their phenotypic expression.

OBJECTIVE

To determine the prevalence of ADPKD and contributions of PKD1, PKD2, and other genes related to cystic kidney disease in a large, unselected cohort.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective observational study used an unselected health system-based cohort in central and northeast Pennsylvania with exome sequencing (enrolled from 2004 to 2020) and electronic health record data (up to October 2021). The genotype-first approach included the entire cohort and the phenotype-first approach focused on patients with ADPKD diagnosis codes, confirmed by chart and imaging review.

EXPOSURES

Loss-of-function (LOF) variants in PKD1, PKD2, and other genes associated with cystic kidney disease (ie, ALG8, ALG9, DNAJB11, GANAB, HNF1B, IFT140, SEC61B, PKHD1, PRKCSH, SEC63); likely pathogenic missense variants in PKD1 and PKD2.

MAIN OUTCOMES AND MEASURES

Genotype-first analysis: ADPKD diagnosis code (Q61.2, Q61.3, 753.13, 753.12); phenotype-first analysis: presence of a rare variant in PKD1, PKD2, or other genes associated with cystic kidney disease.

RESULTS

Of 174 172 patients (median age, 60 years; 60.6% female; 93% of European ancestry), 303 patients had ADPKD diagnosis codes, including 235 with sufficient chart review data for confirmation. In addition to PKD1 and PKD2, LOF variants in IFT140, GANAB, and HNF1B were associated with ADPKD diagnosis after correction for multiple comparisons. Among patients with LOF variants in PKD1, 66 of 68 (97%) had ADPKD; 43 of 43 patients (100%) with LOF variants in PKD2 had ADPKD. In contrast, only 24 of 77 patients (31.2%) with a PKD1 missense variant previously classified as "likely pathogenic" had ADPKD, suggesting misclassification or variable penetrance. Among patients with ADPKD diagnosis confirmed by chart review, 180 of 235 (76.6%) had a potential genetic cause, with the majority being rare variants in PKD1 (127 patients) or PKD2 (34 patients); 19 of 235 (8.1%) had variants in other genes associated with cystic kidney disease. Of these 235 patients with confirmed ADPKD, 150 (63.8%) had a family history of ADPKD. The yield for a genetic determinant of ADPKD was higher for those with a family history of ADPKD compared with those without family history (91.3% [137/150] vs 50.6% [43/85]; difference, 40.7% [95% CI, 29.2%-52.3%]; P < .001). Previously unreported PKD1, PKD2, and GANAB variants were identified with pedigree data suggesting pathogenicity, and several PKD1 missense variants previously reported as likely pathogenic appeared to be benign.

CONCLUSIONS AND RELEVANCE

This study demonstrates substantial genetic and phenotypic variability in ADPKD among patients within a regional health system in the US.

Progression of Chronic Kidney Disease Risk Categories and Risk of Cardiovascular Disease and Total Mortality: Coronary Artery Risk Development in Young Adults Cohort

Background Previous studies of worsening chronic kidney disease (CKD) based on declining estimated glomerular filtration rate (eGFR) or increasing urine albumin-creatinine ratio (UACR) are limited to later middle-age and older adults. We examined associations of CKD progression and incident cardiovascular disease (CVD) and mortality in younger adults. Methods and Results We studied 4382 adults in CARDIA (Coronary Artery Risk Development in Young Adults) initially aged 27 to 41 years and prospectively over 20 years. Five-year transition probabilities across CKD risk categories were based on eGFR and UACR measured at each exam. Proportional hazards models predicted incident CVD and all-cause mortality by time-varying CKD risk category, adjusting for demographics and CVD risk factors. Progression of CKD risk categories over 20 years occurred in 28.7% (1256/4382) of participants, driven by increases in UACR, but including 5.8% (n=255) with eGFR<60 mL/min per 1.73 m² or UACR ≥300 mg/g. Compared with eGFR ≥60 and UACR <10, demographic and smoking-adjusted hazard ratios for CVD were 1.62 (95% CI, 1.21-2.18) for low CKD risk (eGFR ≥60 with UACR 10-29) and 13.65 (95% CI, 7.52-24.79) for very high CKD risk (eGFR <30 or eGFR 30-44 with UACR 30-299; or eGFR 30-59 with UACR ≥300). Corresponding hazard ratios for all-cause mortality were 1.42 (95% CI, 1.08-1.88) and 14.75 (95% CI, 9.97-21.82). Although CVD associations were attenuated after adjustment for mediating CVD risk factors, all-cause mortality associations remained statistically significant. Conclusions Among young to middle-aged adults, progression to higher CKD risk category was common. Routine monitoring eGFR and UACR holds promise for prevention of CVD and total mortality.

Effects of a Dietitian-Led, Telehealth Lifestyle Intervention on Blood Pressure: Results of a Randomized, Controlled Trial

Background Limited data exist on the benefits of lifestyle behavior change delivered using telehealth and web-based applications with varied support on blood pressure (BP). Methods and Results We conducted a 2-site randomized controlled trial at Geisinger (January 2019-March 2021) to compare the efficacy of 2 remotely delivered strategies using web-based applications in participants with 24-hour systolic BP 120-160 mm Hg and body mass index ≥25 kg/m². Both arms received access to web-based applications and the same lifestyle guidance per American Heart Association guidelines. One arm received minimal nonclinical staff support, and the other arm received dietitian support with motivational interviewing during weekly calls. The primary outcome was 12-week change in 24-hour systolic BP. A total of 187 participants were randomly assigned, with 156 (83.4%) completing the trial. In both arms, 24-hour systolic BP was reduced at follow-up, but the difference in BP change was not significant (dietitian-led arm, -6.73 mm Hg [95% CI, -8.64 to -4.82]; minimal-support arm, -4.92 [95% CI, -7.01 to -2.77]; P comparing groups=0.2). The dietitian-support arm had greater 12-week improvements in the secondary outcomes sleep systolic BP (mean, -6.92 versus -1.45; P=0.004), sleep diastolic BP (-3.31 versus 0.73; P=0.001), and self-reported physical activity (866 versus -243 metabolic equivalent task minutes per week; P=0.01) and tended to have improvements in weight loss (-5.11 versus -3.89 kg; P=0.1) and Healthy Eating Index-2015 score (9.23 versus 6.43 units; P=0.09). Conclusions Both the dietitian- and minimal-support interventions reduced 24-hour systolic BP similarly, although the dietitian-led intervention led to greater improvements in several secondary cardiometabolic outcomes. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03700710.

Cardiovascular Effects of Home Dialysis Therapies: A Scientific Statement From the American Heart Association

Cardiovascular disease is the leading cause of morbidity and mortality in patients with end-stage kidney disease. Currently, thrice-weekly in-center hemodialysis for 3 to 5 hours per session is the most common therapy worldwide for patients with treated kidney failure. Outcomes with thrice-weekly in-center hemodialysis are poor. Emerging evidence supports the overarching hypothesis that a more physiological approach to administering dialysis therapy, including in the home through home hemodialysis or peritoneal dialysis, may lead to improvement in several cardiovascular risk factors and cardiovascular outcomes compared with thrice-weekly in-center hemodialysis. The Advancing American Kidney Health Initiative, which has a goal of increasing the use of home dialysis, is aligned with the American Heart Association's 2024 mission to champion a full and healthy life and health equity. We conclude that incorporation of interdisciplinary care models to increase the use of home dialysis therapies in an equitable manner will contribute to the ultimate goal of improving outcomes for patients with kidney failure and cardiovascular disease.

Establishing a National Cardiovascular Disease Surveillance System in the United States Using Electronic Health Record Data: Key Strengths and Limitations

Cardiovascular disease surveillance involves quantifying the evolving population-level burden of cardiovascular outcomes and risk factors as a data-driven initial step followed by the implementation of interventional strategies designed to alleviate this burden in the target population. Despite widespread acknowledgement of its potential value, a national surveillance system dedicated specifically to cardiovascular disease does not currently exist in the United States. Routinely collected health care data such as from electronic health records (EHRs) are a possible means of achieving national surveillance. Accordingly, this article elaborates on some key strengths and limitations of using EHR data for establishing a national cardiovascular disease surveillance system. Key strengths discussed include the: (1) ubiquity of EHRs and consequent ability to create a more "national" surveillance system, (2) existence of a common data infrastructure underlying the health care enterprise with respect to data domains and the nomenclature by which these data are expressed, (3) longitudinal length and detail that define EHR data when individuals repeatedly patronize a health care organization, and (4) breadth of outcomes capable of being surveilled with EHRs. Key limitations discussed include the: (1) incomplete ascertainment of health information related to health care-seeking behavior and the disconnect of health care data generated at separate health care organizations, (2) suspect data quality resulting from the default information-gathering processes within the clinical enterprise, (3) questionable ability to surveil patients through EHRs in the absence of documented interactions, and (4) the challenge in interpreting temporal trends in health metrics, which can be obscured by changing clinical and administrative processes.

The KIDNEYCODE Program: Diagnostic Yield and Clinical Features of Individuals with CKD

Background

Despite increasing recognition that CKD may have underlyi ng genetic causes, genetic testing remains limited. This study evaluated the diagnostic yield and phenotypic spectrum of CKD in individuals tested through the KIDNEYCODE sponsored genetic testing program.

Methods

Unrelated individuals who received panel testing (17 genes) through the KIDNEYCODE sponsored genetic testing program were included. Individuals had to meet at least one of the following eligibility criteria: eGFR ≤90 ml/min per 1.73m² and hematuria or a family history of kidney disease; or suspected/biopsy-confirmed Alport syndrome or FSGS in tested individuals or relatives.

Results

Among 859 individuals, 234 (27%) had molecular diagnoses in genes associated with Alport syndrome (n=209), FSGS (n=12), polycystic kidney disease (n=6), and other disorders (n=8). Among those with positive findings in a COL4A gene, the majority were in COL4A5 (n=157, 72 hemizygous male and 85 heterozygous female individuals). A positive family history of CKD, regardless of whether clinical features were reported, was more predictive of a positive finding than was the presence of clinical features alone. For the 248 individuals who had kidney biopsies, a molecular diagnosis was returned for 49 individuals (20%). Most (n=41) individuals had a molecular diagnosis in a COL4A gene, 25 of whom had a previous Alport syndrome clinical diagnosis, and the remaining 16 had previous clinical diagnoses including FSGS (n=2), thin basement membrane disease (n=9), and hematuria (n=1). In total, 491 individuals had a previous clinical diagnosis, 148 (30%) of whom received a molecular diagnosis, the majority (89%, n=131) of which were concordant.

Conclusions

Although skewed to identify individuals with Alport syndrome, these findings support the need to improve access to genetic testing for patients with CKD-particularly in the context of family history of kidney disease, hematuria, and hearing loss.

Potential implications of the 2021 KDIGO blood pressure guideline for adults with chronic kidney disease in the United States

The 2021 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease (CKD) recommends a target systolic blood pressure under 120 mmHg based on standardized office blood pressure measurement. Here, we examined the potential implications of this new guideline for blood pressure lowering with antihypertensive medication among adults in the United States with CKD compared to the 2012 KDIGO guideline (target blood pressure 130/80 mmHg or under with albuminuria or 140/90 mmHg or under without albuminuria) and the 2017 American College of Cardiology/American Heart Association (target blood pressure under 130/80 mmHg) guideline. Additionally, we determined implications of the 2021 KDIGO guideline for angiotensin converting enzyme inhibitor (ACEi) or angiotensin II-receptor blocker (ARB) use for those with albuminuria (recommended at systolic blood pressure of 120 mmHg or over) compared to the 2012 KDIGO guideline (recommended at blood pressures over 130/80 mmHg). Data were analyzed from 1,699 adults with CKD (estimated glomerular filtration rate 15-59 ml/min/1.73m² or a urinary albumin-to-creatinine ratio of 30 mg/g or more) in the 2015-2018 National Health and Nutrition Examination Survey and averaged up to three standardized blood pressure measurements. Among adults with CKD, 69.5% were eligible for blood pressure lowering according to the 2021 KDIGO guideline, compared with 49.8% as per 2012 KDIGO or 55.6% as per 2017 American College of Cardiology/American Heart Association guidelines. Among those with albuminuria, 78.2% were eligible for ACEi/ARB use by the 2021 KDIGO guideline compared with 71.0% by the 2012 KDIGO guideline. However, only 39.1% were taking an ACEi/ARB. Thus, our findings highlight opportunities to improve blood pressure management and reduce cardiovascular risk among adults in the United States with CKD.

Associations Between Dietary Patterns and Subclinical Cardiac Injury: An Observational Analysis From the DASH Trial

BACKGROUND

The DASH diet has been found to lower blood pressure (BP) and low-density lipoprotein cholesterol levels.

OBJECTIVE

To compare diets rich in fruits and vegetables with a typical American diet in their effects on cardiovascular injury in middle-aged adults without known preexisting cardiovascular disease (CVD).

DESIGN

Observational study based on a 3-group, parallel-design, randomized trial conducted in the United States from 1994 to 1996. (ClinicalTrials.gov: NCT00000544).

SETTING

3 of the 4 original clinical trial centers.

PARTICIPANTS

326 of the original 459 trial participants with available stored specimens.

INTERVENTION

Participants were randomly assigned to 8 weeks of monitored feeding with a control diet typical of what many Americans eat; a diet rich in fruits and vegetables but otherwise similar to the control diet; or the DASH diet, which is rich in fruits, vegetables, low-fat dairy, and fiber and has low levels of saturated fat and cholesterol. Weight was kept constant throughout feeding.

MEASUREMENTS

Biomarkers collected at baseline and 8 weeks: high-sensitivity cardiac troponin I (hs-cTnI), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and high-sensitivity C-reactive protein (hs-CRP).

RESULTS

The mean age of participants was 45.2 years, 48% were women, 49% were black, and mean baseline BP was 131/85 mm Hg. Compared with the control diet, the fruit-and-vegetable diet reduced hs-cTnI levels by 0.5 ng/L (95% CI, -0.9 to -0.2 ng/L) and NT-proBNP levels by 0.3 pg/mL (CI, -0.5 to -0.1 pg/mL). Compared with the control diet, the DASH diet reduced hs-cTnI levels by 0.5 ng/L (CI, -0.9 to -0.1 ng/L) and NT-proBNP levels by 0.3 pg/mL (CI, -0.5 to -0.04 pg/mL). Levels of hs-CRP did not differ among diets. None of the markers differed between the fruit-and-vegetable and DASH diets.

LIMITATION

Short duration, missing specimens, and an inability to isolate the effects of specific foods or micronutrients.

CONCLUSION

Diets rich in fruits and vegetables given over 8 weeks were associated with lower levels of markers for subclinical cardiac damage and strain in adults without preexisting CVD.

PRIMARY FUNDING SOURCE

National Institutes of Health, National Heart, Lung, and Blood Institute.

Survey of current practices from an international task force for gynecological stereotactic ablative radiotherapy

Background

Stereotactic Ablative Radiotherapy (SABR) is an effective treatment that improves local control for many tumours. However, the role of SABR in gynecological cancers (GYN) has not been well-established. We hypothesize that there exists considerable variation in GYN-SABR practice and technique. The goal of this study is to describe clinical and technical factors in utilization of GYN-SABR among 11 experienced radiation oncologists.

Materials and methods

A 63 question survey on GYN-SABR was sent to 11 radiation oncologists (5 countries) who have published original research, conducted trials or have an established program at their institutions. Responses were combined and analyzed at a central institution.

Results

Most respondents indicated that salvage therapy (non-irradiated or re-irradiated field) for nodal (81%) and primary recurrent disease (91%) could be considered standard options for SABR in the setting of inability to administer brachytherapy. All other indications should be considered on clinical trials. Most would not offer SABR as a boost in primary treatment off-trial without absolute contraindications to brachytherapy. Multi-modality imaging is often (91%) used for planning including PET, CT contrast and MRI. There is a wide variation for OAR tolerances however small bowel is considered the dose-limiting structure for most experts (91%). Fractionation schedules range from 3 to 6 fractions for nodal/primary definitive and boost SABR.

Conclusions

Although SABR has become increasingly standard in other oncology disease sites, there remains a wide variation in both clinical and technical factors when treating GYN cancers. Nodal and recurrent disease is considered a potential indication for SABR whereas other indications should be offered on clinical trials. This study summarizes SABR practices among GYN radiation oncologists while further studies are needed to establish consensus guidelines for GYN-SABR treatment.

Heart Disease and Stroke Statistics-2020 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2020 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, metrics to assess and monitor healthy diets, an enhanced focus on social determinants of health, a focus on the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the American Heart Association's 2020 Impact Goals.

RESULTS

Each of the 26 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, healthcare administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Effects of Sodium Reduction on Energy, Metabolism, Weight, Thirst, and Urine Volume: Results From the DASH (Dietary Approaches to Stop Hypertension)-Sodium Trial

Two recent studies challenged traditional paradigms of mammalian sodium physiology, suggesting that sodium reduction might cause weight gain by altering metabolism. This new theory has important implications for population-wide dietary recommendations. However, these observations have not been confirmed. In the DASH (Dietary Approaches to Stop Hypertension)-Sodium trial, 412 adults with systolic blood pressure of 120 to 159 mm Hg and diastolic blood pressure of 80 to 95 mm Hg not taking antihypertensive medications were randomly assigned to the DASH diet or a control diet (parallel design). On their assigned diet, participants randomly consumed each of the 3 sodium levels for 4 weeks (crossover design). Participants were provided all meals but could drink noncaloric beverages (eg, water) freely. Throughout the trial, energy intake was adjusted to maintain weight constant. The 3 sodium levels (at 2100 kcal/day) were: low (1150 mg of Na/day), medium (2300 mg of Na/day), and high (3450 mg of Na/day). Energy intake, weight, self-reported thirst, and 24-hour urine volume were assessed after each period. Participants were 57% women and 57% black; mean age was 48 years [SD, 10]). Among those assigned the control, mean weight increased slightly with higher sodium but not among those assigned DASH. Energy intake did not vary across sodium levels in either diet (P-trends ≥0.36). Higher sodium resulted in more thirst (P-trends <0.001 on both diets) and higher urine volume (suggesting higher fluid intake) during the control diet (P-trend=0.007). Reducing sodium did not increase energy requirements to maintain stable weights but did decrease thirst and urine volume (control diet only), findings consistent with the traditional understanding of mammalian sodium physiology. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000608.

Abstract OT2-04-02: A phase 3 study of post-lumpectomy radiotherapy to whole breast + regional lymph nodes vs whole breast alone for patients with pN1 breast cancer treated with taxane-based chemotherapy (KROG 1701): Trial in progress

Background

In patients with early stage breast cancer, regional nodal irradiation (RNI) is added to whole breast irradiation (WBI) in order to control microscopic regional disease and to prevent systemic spread of cancer. According to recent randomized trials (MA.20 and EORTC 22922-10925), prophylactic RNI was associated with improvement in disease-free survival (DFS) in the patients with high-risk node negative or pN1 breast cancer. However, systemic agents now known to improve loco-regional control, such as taxane or endocrine therapy, were prescribed to a small percentage of patients in the studies. The benefit of RNI found in the previous studies might be attributed to incorporation of less effective systemic treatments. The impact of prophylactic RNI in pN1 breast cancer should be evaluated in the patients receiving modern systemic treatment. The current study was conducted to compare the effect of post-lumpectomy WBI vs WBI plus RNI on DFS in pN1 breast cancer patients who received adjuvant taxane-based chemotherapy.

Methods

This study is a multicenter, phase 3, randomized controlled non-inferiority trial (NCT03269981). Eligibility criteria are ≥ 20 years female; pathologically proven invasive carcinoma of the breast; one to three positive axillary lymph nodes (pN1) in pathologic specimen; receiving breast-conserving surgery followed by taxane-based chemotherapy; having adjuvant endocrine therapy or anti-HER2 treatment according to molecular subtype of tumor. Patients are randomly assigned in a 1:1 ratio to receive WBI or WBI plus RNI. Patient randomization was stratified by molecular subtype of tumor (i.e. luminal A/luminal B/luminal HER2/HER2-enriched/triple-negative) and methods of axillary management (i.e. sentinel lymph node biopsy/axillary lymph node dissection). The primary outcome is DFS. The secondary outcomes include DFS according to molecular subtype, treatment-related toxicity, and patient's quality of life per EORTC QLQ-C30 and QLQ-BR23. Patients will be followed for survival and disease recurrence for seven years. A total of 1,926 patients are planned to be enrolled, with recruitment initiated in April 2017. As of June 2018, a total of 236 patients were enrolled.

Acknowledgement

This study was supported by a grant from the National R&D Program for Cancer Control, Ministry of Health & Welfare, Republic of Korea (grant number: HA17C0043010018).

Citation Format: Kim H, Park W, Choi DH, Ahn SJ, Kim SS, Kim ES, Lee JH, Lee KC, Kim JH, Lee H-S, Kim JH, Kim MY, Park HJ, Kim K, Song SH, Kwon J, Lee IJ, Kim TH, Kim TG, Chang AR, Cho O, Jeong BK, Ha B, Lee J, Ki Y. A phase 3 study of post-lumpectomy radiotherapy to whole breast + regional lymph nodes vs whole breast alone for patients with pN1 breast cancer treated with taxane-based chemotherapy (KROG 1701): Trial in progress [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-04-02.

CKD and Risk for Hospitalization With Infection: The Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Individuals on dialysis therapy have a high risk for infection, but risk for infection in earlier stages of chronic kidney disease has not been comprehensively described.

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

9,697 participants (aged 53-75 years) in the Atherosclerosis Risk in Communities (ARIC) Study. Participants were followed up from 1996 to 1998 through 2011.

PREDICTORS

Estimated glomerular filtration rate (eGFR) and urinary albumin-creatinine ratio (ACR).

OUTCOMES

Risk for hospitalization with infection and death during or within 30 days of hospitalization with infection.

RESULTS

During follow-up (median, 13.6 years), there were 2,701 incident hospitalizations with infection (incidence rate, 23.6/1,000 person-years) and 523 infection-related deaths. In multivariable analysis, HRs of incident hospitalization with infection as compared to eGFRs≥90mL/min/1.73m² were 2.55 (95% CI, 1.43-4.55), 1.48 (95% CI, 1.28-1.71), and 1.07 (95% CI, 0.98-1.16) for eGFRs of 15 to 29, 30 to 59, and 60 to 89mL/min/1.73m², respectively. Corresponding HRs were 3.76 (95% CI, 1.48-9.58), 1.62 (95% CI, 1.20-2.19), and 0.99 (95% CI, 0.80-1.21) for infection-related death. Compared to ACRs<10mg/g, HRs of incident hospitalization with infection were 2.30 (95% CI, 1.81-2.91), 1.56 (95% CI, 1.36-1.78), and 1.34 (95% CI, 1.20-1.50) for ACRs≥300, 30 to 299, and 10 to 29mg/g, respectively. Corresponding HRs were 3.44 (95% CI, 2.28-5.19), 1.57 (95% CI, 1.18-2.09), and 1.39 (95% CI, 1.09-1.78) for infection-related death. Results were consistent when separately assessing risk for pneumonia, kidney and urinary tract infections, bloodstream infections, and cellulitis and when taking into account recurrent episodes of infection.

LIMITATIONS

Outcome ascertainment relied on diagnostic codes at time of discharge.

CONCLUSIONS

Increasing provider awareness of chronic kidney disease as a risk factor for infection is needed to reduce infection-related morbidity and mortality.

Effects of intensive insulin therapy alone and in combination with pioglitazone on body weight, composition, distribution and liver fat content in patients with type 2 diabetes

AIM

To evaluate the effects of intensive insulin therapy alone and with added pioglitazone on body weight, fat distribution, lean body mass (LBM) and liver fat in type 2 diabetic patients.

METHODS

Twenty-five insulin-treated, obese patients with type 2 diabetes were randomized to addition of pioglitazone 45 mg (n = 12) or placebo (n = 13) and treated intensively for 12-16 weeks. Dual-energy X-ray absorptiometry/abdominal computed tomography scans were performed before/after treatment. LBM, visceral/subcutaneous adipose tissue (VAT/SAT) and liver/spleen (L/S) attenuation ratios were measured pre-/posttreatment (a ratio <1 represents fatty liver).

RESULTS

Intensive insulin alone and insulin + pioglitazone significantly improved glycaemic control (7.8 ± 0.3 to 7.2 ± 0.3% and 7.6 ± 0.3 to 7.1 ± 0.4%, respectively). Body weight gain was greater with insulin + pioglitazone (4.9 ± 4.5 kg) versus insulin therapy alone (1.7 ± 0.7 kg). SAT increased significantly with pioglitazone + insulin therapy (393.9 ± 48.5 to 443.2 ± 56.7 cm(2) , p < 0.01) compared to a non-significant increase with insulin therapy alone (412.9 ± 42.5 to 420.8 ± 43.8 cm(2) ). VAT decreased non-significantly in both groups (240.3 ± 41.7 to 223.8 ± 38.1 cm(2) with insulin + pioglitazone and 266.6 ± 27.4 to 250.5 ± 22.2 cm(2) with insulin therapy). LBM increased significantly by 1.92 ± 0.74 kg with insulin + pioglitazone treatment. The L/S attenuation ratio in the placebo + insulin group decreased from 1.08 ± 0.1 to 1.04 ± 0.1 (p = ns) and increased from 1.00 ± 0.1 to 1.08 ± 0.05 (p = 0.06) in the pioglitazone + insulin group.

CONCLUSIONS

Intensification of insulin therapy in type 2 diabetic patients causes modest weight gain and no change in body fat distribution, LBM or liver fat. In contrast, the addition of pioglitazone, at equivalent glycaemia, increases weight gain, fat mass and SAT; increases LBM and tends to decrease liver fat. These changes in fat distribution may contribute to the beneficial effects of pioglitazone, despite greater weight gain.

Effects of intensive insulin therapy alone and with added pioglitazone on renal salt/water balance and fluid compartment shifts in type 2 diabetes

OBJECTIVE

To evaluate the effects of intensive insulin therapy alone or with added pioglitazone on renal salt/water balance and body fluid compartment shifts in type 2 diabetes.

METHODS

A total of 25 insulin-treated, obese patients with type 2 diabetes were randomized to pioglitazone 45 mg (n = 12) or placebo (n = 13) and treated intensively for 12-16 weeks to achieve equivalent glycaemic control. We measured total body water (TBW) and extracellular/intracellular fluid by bioimpedance analysis; plasma/RBC volume with I(131)albumin; sodium handling by fractional excretion of sodium/lithium (FeNa/FeLi) and other renal/hormonal parameters.

RESULTS

Intensification of insulin therapy and the addition of pioglitazone significantly improved glycaemia (HbA1C 7.8-7.2% and 7.6-7.1%) and increased body weight (1.7 and 4.9 kg) respectively. TBW increased 1.7 l with insulin alone (65% intracellular) and 1.6 l with added pioglitazone (75% extracellular) (p = 0.06 and 0.09 respectively). Plasma volume increased 0.2 +/- 0.1 l with insulin alone (p = 0.05) and 0.4 +/- 0.1 l with added pioglitazone (p < 0.05). Extravascular, extracellular (interstitial) fluid increased significantly and more with added pioglitazone (0.8 +/- 0.2 l, p < 0.01) than with insulin alone (0.4 +/- 0.2 l, p = ns). At steady-state, FeLi (marker of proximal-tubular sodium delivery to the distal nephron) increased significantly with added pioglitazone (12.4 +/- 1.3 to 18.0 +/- 3.2%) vs. no significant change with insulin alone (15.4 +/- 1.2 to 14.5 +/- 2.3%). There were no significant changes in the other parameters.

CONCLUSION

In intensively insulin-treated obese type 2 diabetic patients, at equivalent glycaemic control, the addition of pioglitazone causes greater weight gain, but a similar increase in body water that is mainly extracellular and interstitial compared with intracellular increase with insulin therapy alone. Pioglitazone also increases the filtered load of sodium reabsorbed at the distal nephron with no net change in FeNa.

Age distribution of human papillomavirus infection and cervical neoplasia reflects caveats of cervical screening policies

Although a second age-related peak of human papillomavirus (HPV) infection is observed in many populations, it does not seem to have any impact on cervical screening policies. We examined the age-specific prevalence of HPV infection among 2,604 women enrolled for cervical screening and correlated the age at diagnosis of 2,491 cervical intraepithelial neoplasia Grade 2/3 (CIN2/3) lesions and 801 invasive cervical cancers (ICC). Two peaks of HPV infection were detected at 26-30 and 46-50 years, respectively. The first infection peak was followed by a CIN2/3 peak and an ICC peak at 5-15 and 15 years later, respectively. The second infection peak was followed by an ICC peak 20 years later, but strikingly no CIN2/3 peak was detected in between and thus eliminated an opportunity of treating the lesions at preinvasive stages. The most plausible explanation is that women at the expected second CIN2/3 peak (50-65 years) are not having Pap smears under the current opportunistic screening program. Furthermore, women of this age may have physiological retraction of the transformation zone, and CIN lesions may remain undetected if an adequate Pap smear sample is not obtained. To combat this problem, the screening program in Hong Kong needs to focus on women aged 50 years and older and a mop-up screening up to 75 years is necessary. Bimodal peaks of HPV infection and cervical cancer are seen in many countries and the analysis of population-specific age distribution of CIN2/3 should be an integral exercise in evaluating the effectiveness of a screening program.

Epidemiologic risk profile of infection with different groups of human papillomaviruses

This study identified the age-specific prevalence and epidemiologic risk profile for infection with different groups and species of human papillomaviruses (HPV). Structured interview and HPV testing were conducted for 2,604 Chinese women self-referred for cervical screening. Independent risk factors for infection were identified by multiple logistic regressions. Overall, a major peak of HPV infection was observed at women aged 26-30 years, and a minor peak at 46-55 years. This pattern was observed for high-risk, low-risk, and alpha-5/7/9 HPVs; but alpha-3/6 HPVs showed peaks of similar magnitudes in young and older women. Independent risk factors for HPV infection (all types combined) included younger age (OR [95% CI] for >55 vs. < or =30 years = 0.22 [0.09-0.55]; 31-45 vs. < or = 30 years = 0.57 [0.33-0.99]), having > or =4 lifetime sexual partners (2.28 [1.06-4.88]), and smoking (2.24 [1.22-4.10]). Young age and smoking were the most consistent independent risk factors observed across different HPV groups. The risk profile for high-risk HPV was similar to alpha-5/7/9. Single-type infection was associated with having more sexual partners, higher education level and oral contraception; whereas multiple-type infection was associated with smoking. In conclusion, a U-shaped age-specific prevalence curve was observed for HPV infection overall, but with a different pattern for different HPV species. Different HPV groups showed variations in their risk profiles. These data are useful for formulating preventative strategy for HPV-related diseases. Catch-up vaccination program in Hong Kong should cover a wider age group as the first peak of infection occurred relatively late.

Comparative validation of c-kit exon 11 mutation analysis on cytology samples and corresponding surgical resections of gastrointestinal stromal tumours

OBJECTIVE

Studies have shown that c-kit mutation analysis of gastrointestinal stromal tumours (GISTs) obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) can be routinely performed. We validated c-kit exon 11 mutational analysis on cell block material obtained from fine needle aspiration cytology (FNAC) for diagnostic purposes and compared it with the same analysis in formalin-fixed paraffin-embedded full sections of the corresponding resection specimens.

METHODS

c-kit mutation analysis was done on cell block material obtained from ten cases encountered in our department from 1999 to 2008 on which FNAC was attempted pre-operatively. The findings were compared with analysis on full paraffin section of the corresponding resected tumours in seven cases where patients opted for resection. c-kit exon 11 was examined via bidirectional nucleic acid sequencing.

RESULTS

Our results showed 100% concordance for the presence and type of exon 11 mutation in the resected and aspirated tumours in all seven cases. These mutations had diagnostic value when compared with other neoplasms that are part of the cytomorphological differential diagnosis, such as leiomyosarcoma or gastric adenocarcinomas.

CONCLUSION

Molecular cytopathology is a powerful tool that can complement morphology and immunohistochemical assessment of cytological material in routine practice for the diagnosis and prognostication of GISTs. We briefly discuss the advantages and limitations of the fine needle method of obtaining tissue for the diagnosis and prognostication of GISTs, and its current therapeutic strategies.

Rapid diagnosis of Penicillium marneffei infection by fine needle aspiration cytology

This report describes the use of fine needle aspiration (FNA) cytology to make a rapid diagnosis of Penicillium marneffei infection in an HIV positive patient. P marneffei is a thermally dimorphic fungus that is a mould at 25 degrees C and a yeast at 37 degrees C. It multiplies by fission. It can be easily mistaken for various other infections that are characterised by the presence of histiocytes with phagocytosed yeast cells. In smears the demonstration of yeast cells with a distinctive central septum confirms the diagnosis.

Increased prevalence of squamous intraepithelial lesions in systemic lupus erythematosus: association with human papillomavirus infection

OBJECTIVE

To compare the prevalence of abnormal Pap smears in patients with systemic lupus erythematosus (SLE) with that in a large group of healthy controls, and to determine whether SLE itself is an independent risk factor. The association of human papillomavirus (HPV) infection and the use of immunosuppressive agents with abnormal Pap smears in SLE was also assessed.

METHODS

Eighty-five SLE patients participated in this cross-sectional study. A sample of cervical cells was collected from each patient for routine cytologic examination. HPV was typed by restriction and sequencing analysis. A structured questionnaire was administered to the subjects to ascertain the possible behavioral and biologic risk factors associated with cervical atypia. Data on 2,080 healthy female subjects were retrieved for comparison.

RESULTS

The mean (+/-SD) age of SLE patients and controls was 42 +/- 9 years and 44 +/- 10 years, respectively. The prevalence of abnormal Pap smears was significantly increased in SLE patients compared with controls (16.5% versus 5.7%). The prevalence of squamous intraepithelial lesions was increased approximately 6-fold in SLE patients (11.8%) compared with controls (2.0%). SLE itself remained an independent risk factor for abnormal Pap smears (odds ratio 3.5, 95% confidence interval 1.8-6.9). The overall prevalence of HPV infection in SLE patients and controls was 11.8% and 7.3%, respectively. However, 10.6% of SLE patients were infected with at least 1 high-risk type of HPV, compared with 4.2% of controls. Multiple infections were also more common in SLE patients than in controls (4.7% versus 1.1%). There were no significant differences in the use of immunosuppressive agents between SLE patients with normal Pap smears and those with abnormal Pap smears.

CONCLUSION

Abnormal Pap smears were more common among SLE patients than controls, even after adjusting for HPV status. SLE-associated immunosuppression increases susceptibility to high-risk HPV infection and multiple HPV infections. The use of immunosuppressant agents was not associated with abnormal Pap smears.

The pivotal role of the pathology laboratory in the context of a Singapore cervical cancer screening programme

Singapore is poised to implement a national cervical screening programme and pathology laboratories have a pivotal role to play. This review describes the laboratory examination of Pap smears and the importance of providing a first class service. This will require sufficient experienced cyto-technologists and pathologists. There also needs to be a mechanism in place to monitor all stages of the Pap smear, from the time it is taken until it is reported. The Bethesda System for reporting Pap smears, new smear collection devices, liquid-based specimens, use of computer screening and other measures to enhance laboratory standards, are also discussed.

Clonal analysis of bilateral mammary carcinomas by clinical evaluation and partial allelotyping

Bilateral breast carcinomas may represent contralateral metastases or new primary tumors. The presence of carcinoma in situ, a lower grade, or a different histotype in the second tumor is considered a clinical criterion for a second primary tumor. In this study, 26 bilateral breast carcinomas from 13 patients were analyzed based on clinical criteria, and the results were compared with those obtained by partial allelotyping using 47 markers at 7 chromosomal arms. Of the 8 synchronous tumors, 5 were concluded to be distinct primary tumors using clinical criteria; some were confirmed by partial allelotyping. In the remaining 3 cases, partial allelotyping showed distinct primary tumors. Five patients had metachronous carcinomas with 3 distinct primary tumors, 1 metastasis, and 1 that was uncertain by clinical criteria. Three cases were confirmed by partial allelotyping, and the uncertain case was shown to be distinct primary tumors. No discrepant results were noted. Stringent application of clinical criteria is accurate for differentiating second primary tumors from metastases.

Prevalence and genotype distribution of cervical human papillomavirus infection: Comparison between pregnant women and non-pregnant controls

Controversies exist on the effect of pregnancy on human papillomavirus (HPV) infection. A cross-sectional section study was conducted to compare the prevalence and genotype distribution of cervical HPV infection between pregnant and non-pregnant women in Hong Kong. Cervical samples were collected from 308 pregnant women and from the same number of age-matched controls recruited from a cervical cancer screening center located at the same hospital. HPV was detected by the polymerase chain reaction, followed by genotype identification by restriction fragment length polymorphism and direct sequencing analyses. The prevalence of HPV for pregnant women was 10.1%, without significant variation with age, gestation, gravidity and parity. The prevalence of HPV for non-pregnant group was 11.4% and did not show significant difference when compared to the pregnant group either by overall or age-stratified subgroup analyses. When the analysis was stratified according to the risk-type of HPV infection, still no significant difference between pregnant and non-pregnant groups was observed (all types: 10.1 vs. 11.4%, P = 0.602; high-risk types: 5.8 vs. 7.8%, P = 0.338; low-risk types: 1.0 vs. 2.9%, P = 0.080; unknown-risk types: 3.2% vs. 1.3%, P = 0.105). The results of this study show no evidence for an influence of pregnancy on HPV prevalence, and a majority of HPV-infected pregnant women had normal cervical cytology. HPV positive results in pregnant women per se should be managed conservatively.

Quantitative Epstein-Barr virus DNA analysis and detection of gene promoter hypermethylation in nasopharyngeal (NP) brushing samples from patients with NP carcinoma

PURPOSE

Nasopharyngeal carcinoma (NPC) is highly prevalent in southern China and characterized by a strong association with EBV. We aimed to detect EBV DNA and cancer-related gene promoter hypermethylation in nasopharyngeal (NP) brushing samples and provide a novel noninvasive approach for NPC detection.

EXPERIMENTAL DESIGN

Twenty-eight NPC cases and 26 noncancerous subjects were prospectively recruited. NP brushing samples were subjected to quantitative real-time PCR analysis of EBV DNA and methylation-specific PCR analysis of the DAP-kinase, RASSF1A, and p16 genes.

RESULTS

EBV DNA quantity in NP brushing samples from NPC patients (median, 8.94 copies/actin) was significantly higher than that of controls (median, 0 copies/actin; P < 0.0001). Twenty-seven of 28 NPC patients had detectable EBV DNA in NP brushes, whereas 25 of 26 controls had undetectable or very low levels of EBV DNA. Elevated EBV DNA level in brushing samples as a tumor marker had a sensitivity of 96.4% and a specificity of 96.2% for NPC detection. Moreover, T(1) disease had a significantly lower EBV DNA level as compared with locally more advanced disease (P = 0.037). In brushing samples of NPC patients, the frequencies of DAP-kinase, RASSF1A, and p16 promoter hypermethylation were 50.0%, 39.3%, and 46.4%, respectively. Seventy-eight percent of cases showed methylation of at least one gene. No aberrant hypermethylation was detected in control samples.

CONCLUSIONS

Our study demonstrated the feasibility of detecting multiple molecular tumor markers in NP brushing samples with a high sensitivity and specificity for NPC detection. It offers a powerful yet noninvasive approach for the diagnosis of NPC in high-risk populations.

Metachronous bilateral mammary metaplastic and infiltrating duct carcinomas: a molecular study for clonality

Mammary metaplastic carcinoma is uncommon. In this study, both carcinoma and sarcoma components of a metaplastic carcinoma and a subsequent metachronous contralateral infiltrating ductal carcinoma were analyzed by microsatellite analysis for the loss of heterozygosity (LOH) patterns at multiple sites on chromosome arms 3p, 6q, 8, 9p, 11, 13q, 14q, 16q, and 17p. The LOH patterns between the carcinoma and sarcoma components in the first tumor were similar, indicating clonality. The LOH patterns between the first and second tumors were different at all chromosome arms, indicating different clonality and a second primary. We demonstrated a second primary carcinoma in a patient with previous metaplastic carcinoma rather than a metastasis with carcinoma component only.