Faculty Bibliography

BACKGROUND:Trends in the prevalence and control of diabetes defined by hemoglobin A1c (HbA1c) levels are important for health care policy and planning. OBJECTIVE:To update trends in the prevalence of diabetes, prediabetes, and glycemic control. DESIGN/METHODS:Cross-sectional. SETTING/METHODS:NHANES (National Health and Nutrition Examination Survey) in 1988-1994 and 1999-2010. PARTICIPANTS/METHODS:Adults aged 20 years or older. MEASUREMENTS/METHODS:We used calibrated HbA1c levels to define undiagnosed diabetes (≥6.5%); prediabetes (5.7% to 6.4%); and, among persons with diagnosed diabetes, glycemic control (<7.0% or <8.0%). Trends in HbA1c categories were compared with fasting glucose levels (≥7.0 mmol/L [≥126 mg/dL] and 5.6 to 6.9 mmol/L [100 to 125 mg/dL]). RESULTS:In 2010, approximately 21 million U.S. adults aged 20 years or older had total confirmed diabetes (self-reported diabetes or diagnostic levels for both fasting glucose and calibrated HbA1c). During 2 decades, the prevalence of total confirmed diabetes increased, but the prevalence of undiagnosed diabetes remained fairly stable, reducing the proportion of total diabetes cases that are undiagnosed to 11% in 2005-2010. The prevalence of prediabetes was lower when defined by calibrated HbA1c levels than when defined by fasting glucose levels but has increased from 5.8% in 1988-1994 to 12.4% in 2005-2010 when defined by HbA1c levels. Glycemic control improved overall, but total diabetes prevalence was greater and diabetes was less controlled among non-Hispanic blacks and Mexican Americans compared with non-Hispanic whites. LIMITATION/CONCLUSIONS:Cross-sectional design. CONCLUSION/CONCLUSIONS:Over the past 2 decades, the prevalence of total diabetes has increased substantially. However, the proportion of undiagnosed diabetes cases decreased, suggesting improvements in screening and diagnosis. Among the growing number of persons with diagnosed diabetes, glycemic control improved but remains a challenge, particularly among non-Hispanic blacks and Mexican Americans. PRIMARY FUNDING SOURCE/BACKGROUND:National Institutes of Health.

BACKGROUND AND PURPOSE/OBJECTIVE:Epidemiological studies show strong associations between kidney dysfunction and risk of ischemic stroke (IS), the mechanisms of which are incompletely understood. We investigated whether these associations may reflect shared heritability because of a common polygenic basis and whether this differed for IS subtypes. METHODS:Polygenic models were derived using genome-wide association studies meta-analysis results for 3 kidney traits: estimated glomerular filtration rate using serum creatinine (eGFRcrea: n=73 998), eGFR using cystatin C (eGFRcys: n=22 937), and urinary albumin to creatinine ratio (n=31 580). For each, single nucleotide polymorphisms passing 10 P value thresholds were used to form profile scores in 4561 IS cases and 7094 controls from the United Kingdom, Germany, and Australia. Scores were tested for association with IS and its 3 aetiological subtypes: large artery atherosclerosis, cardioembolism, and small vessel disease. RESULTS:Polygenic scores correlating with higher eGFRcrea were associated with reduced risk of large artery atherosclerosis, with 5 scores reaching P<0.05 (peak P=0.004) and all showing the epidemiologically expected direction of effect. A similar pattern was observed for polygenic scores reflecting higher urinary albumin to creatinine ratio, of which 3 associated with large artery atherosclerosis (peak P=0.01) and all showed the expected directional association. One urinary albumin to creatinine ratio-based score also associated with small vessel disease (P=0.03). The global pattern of results was unlikely to have occurred by chance (P=0.02). CONCLUSIONS:This study suggests possible polygenic correlation between renal dysfunction and IS. The shared genetic components may be specific to stroke subtypes, particularly large artery atherosclerotic stroke. Further study of the genetic relationships between these disorders seems merited.

BACKGROUND:Few reports have shown an association between access type and inflammatory marker levels in a longitudinal cohort. We investigated the role of access type on serial levels of inflammatory markers and the role of inflammatory markers in mediating the association of access type and risk of mortality in a prospective study of incident dialysis patients. STUDY DESIGN/METHODS:Cohort study, post hoc analysis of the CHOICE (Choices for Healthy Outcomes in Caring for ESRD) Study. SETTING & PARTICIPANTS/METHODS:In 583 participants, inflammation was assessed by measuring serum C-reactive protein (CRP) and interleukin 6 (IL-6) after access placement and at multiple times during 3 years' follow-up. Type of access was categorized as central venous catheter (CVC), arteriovenous graft (AVG), and arteriovenous fistula (AVF), and changes over time were recorded. PREDICTOR/METHODS:Access type, age, sex, race, body mass index, diabetes, cardiovascular disease, and serum albumin level. OUTCOMES/RESULTS:CRP level, IL-6 level, and mortality. MEASUREMENTS/METHODS:We used mixed-effects pattern mixture models to study the association between access type and repeated measurements of inflammation and survival analysis to investigate the association of access type and mortality, adjusting for predictors. RESULTS:In a mixed-effects pattern mixture model, compared with AVFs, the presence of CVCs and AVGs was associated with 62% (P=0.02) and 30% (P=0.05) increases in average CRP levels, respectively. A Cox proportional hazards model yielded nonsignificant associations of CVC and AVG use (vs AVFs) with risk of mortality when adjusted for inflammatory marker levels. Higher CRP levels were associated with increased risk of CVC failure than lower CRP levels. LIMITATIONS/CONCLUSIONS:CRP and IL-6 measurements not performed for all hemodialysis patients. CONCLUSIONS:CVCs, compared with AVFs, are associated with a greater state of inflammation in incident hemodialysis patients, and the association of catheter use and mortality may be mediated by access-induced inflammation. Our findings support recommendations for the early removal or avoidance of CVC placements.

IMPORTANCE/OBJECTIVE:The established chronic kidney disease (CKD) progression end point of end-stage renal disease (ESRD) or a doubling of serum creatinine concentration (corresponding to a change in estimated glomerular filtration rate [GFR] of −57% or greater) is a late event. OBJECTIVE:To characterize the association of decline in estimated GFR with subsequent progression to ESRD with implications for using lesser declines in estimated GFR as potential alternative end points for CKD progression. Because most people with CKD die before reaching ESRD, mortality risk also was investigated. DATA SOURCES AND STUDY SELECTION/METHODS:Individual meta-analysis of 1.7 million participants with 12,344 ESRD events and 223,944 deaths from 35 cohorts in the CKD Prognosis Consortium with a repeated measure of serum creatinine concentration over 1 to 3 years and outcome data. DATA EXTRACTION AND SYNTHESIS/METHODS:Transfer of individual participant data or standardized analysis of outputs for random-effects meta-analysis conducted between July 2012 and September 2013, with baseline estimated GFR values collected from 1975 through 2012. MAIN OUTCOMES AND MEASURES/METHODS:End-stage renal disease (initiation of dialysis or transplantation) or all-cause mortality risk related to percentage change in estimated GFR over 2 years, adjusted for potential confounders and first estimated GFR. RESULTS:The adjusted hazard ratios (HRs) of ESRD and mortality were higher with larger estimated GFR decline. Among participants with baseline estimated GFR of less than 60 mL/min/1.73 m2, the adjusted HRs for ESRD were 32.1 (95% CI, 22.3-46.3) for changes of −57% in estimated GFR and 5.4 (95% CI, 4.5-6.4) for changes of −30%. However, changes of −30% or greater (6.9% [95% CI, 6.4%-7.4%] of the entire consortium) were more common than changes of −57% (0.79% [95% CI, 0.52%-1.06%]). This association was strong and consistent across the length of the baseline period (1 to 3 years), baseline estimated GFR, age, diabetes status, or albuminuria. Average adjusted 10-year risk of ESRD (in patients with a baseline estimated GFR of 35 mL/min/1.73 m2) was 99% (95% CI, 95%-100%) for estimated GFR change of −57%, was 83% (95% CI, 71%-93%) for estimated GFR change of −40%, and was 64% (95% CI, 52%-77%) for estimated GFR change of −30% vs 18% (95% CI, 15%-22%) for estimated GFR change of 0%. Corresponding mortality risks were 77% (95% CI, 71%-82%), 60% (95% CI, 56%-63%), and 50% (95% CI, 47%-52%) vs 32% (95% CI, 31%-33%), showing a similar but weaker pattern. CONCLUSIONS AND RELEVANCE/CONCLUSIONS:Declines in estimated GFR smaller than a doubling of serum creatinine concentration occurred more commonly and were strongly and consistently associated with the risk of ESRD and mortality, supporting consideration of lesser declines in estimated GFR (such as a 30% reduction over 2 years) as an alternative end point for CKD progression.

OBJECTIVE:Traditional predictors suboptimally predict cardiovascular disease (CVD) in individuals with chronic kidney disease (CKD). This study compared 5 nontraditional cardiac and kidney markers on the improvement of cardiovascular prediction among those with CKD. APPROACH AND RESULTS/RESULTS:Among 8622 participants aged 52 to 75 years in the Atherosclerosis Risk in Communities (ARIC) Study, cardiac troponin T, N-terminal pro-B-type natriuretic peptide, cystatin C, β2-microglobulin, and β-trace protein were compared for improvement in predicting incident CVD after stratifying by CKD status (940 participants with CKD [kidney dysfunction or albuminuria]). During a median follow-up of 11.9 years, there were 1672 CVD events including coronary disease, stroke, and heart failure (336 cases in CKD). Every marker was independently associated with incident CVD in participants with and without CKD. The adjusted hazard ratios (per 1 SD) were larger for cardiac markers than for kidney markers, particularly in CKD (1.61 [95% confidence interval, 1.43-1.81] for cardiac troponin T, 1.50 [1.34-1.68] for N-terminal pro-B-type natriuretic peptide, and <1.26 for kidney markers). Particularly in CKD group, cardiac markers compared with kidney markers contributed to greater c-statistic increment (0.032-0.036 versus 0.012-0.015 from 0.679 with only conventional predictors in CKD and 0.008-0.011 versus 0.002-0.010 from 0.697 in non-CKD) and categorical net reclassification improvement (0.086-0.127 versus 0.020-0.066 in CKD and 0.057-0.077 versus 0.014-0.048 in non-CKD). The superiority of cardiac markers was largely consistent in individual CVD outcomes. CONCLUSIONS:A greater improvement in cardiovascular prediction was observed for cardiac markers than for kidney markers in people with CKD. These results suggest that cardiac troponin T and N-terminal pro-B-type natriuretic peptide are useful for better CVD risk classification in this population.

OBJECTIVE:To use the rs1229984 variant in the alcohol dehydrogenase 1B gene (ADH1B) as an instrument to investigate the causal role of alcohol in cardiovascular disease. DESIGN/METHODS:Mendelian randomisation meta-analysis of 56 epidemiological studies. PARTICIPANTS/METHODS:261 991 individuals of European descent, including 20 259 coronary heart disease cases and 10 164 stroke events. Data were available on ADH1B rs1229984 variant, alcohol phenotypes, and cardiovascular biomarkers. MAIN OUTCOME MEASURES/METHODS:Odds ratio for coronary heart disease and stroke associated with the ADH1B variant in all individuals and by categories of alcohol consumption. RESULTS:Carriers of the A-allele of ADH1B rs1229984 consumed 17.2% fewer units of alcohol per week (95% confidence interval 15.6% to 18.9%), had a lower prevalence of binge drinking (odds ratio 0.78 (95% CI 0.73 to 0.84)), and had higher abstention (odds ratio 1.27 (1.21 to 1.34)) than non-carriers. Rs1229984 A-allele carriers had lower systolic blood pressure (-0.88 (-1.19 to -0.56) mm Hg), interleukin-6 levels (-5.2% (-7.8 to -2.4%)), waist circumference (-0.3 (-0.6 to -0.1) cm), and body mass index (-0.17 (-0.24 to -0.10) kg/m(2)). Rs1229984 A-allele carriers had lower odds of coronary heart disease (odds ratio 0.90 (0.84 to 0.96)). The protective association of the ADH1B rs1229984 A-allele variant remained the same across all categories of alcohol consumption (P=0.83 for heterogeneity). Although no association of rs1229984 was identified with the combined subtypes of stroke, carriers of the A-allele had lower odds of ischaemic stroke (odds ratio 0.83 (0.72 to 0.95)). CONCLUSIONS:Individuals with a genetic variant associated with non-drinking and lower alcohol consumption had a more favourable cardiovascular profile and a reduced risk of coronary heart disease than those without the genetic variant. This suggests that reduction of alcohol consumption, even for light to moderate drinkers, is beneficial for cardiovascular health.

INTRODUCTION/BACKGROUND:The last decade has seen many changes in graduate medical education training in the USA, most notably the implementation of duty hour standards for residents by the Accreditation Council of Graduate Medical Education. As educators are left to balance more limited time available between patient care and resident education, new methods to augment traditional graduate medical education are needed. OBJECTIVES/OBJECTIVE:To assess acceptance and use of a novel gamification-based medical knowledge software among internal medicine residents and to determine retention of information presented to participants by this medical knowledge software. METHODS:We designed and developed software using principles of gamification to deliver a web-based medical knowledge competition among internal medicine residents at the University of Alabama (UA) at Birmingham and UA at Huntsville in 2012-2013. Residents participated individually and in teams. Participants accessed daily questions and tracked their online leaderboard competition scores through any internet-enabled device. We completed focus groups to assess participant acceptance and analysed software use, retention of knowledge and factors associated with loss of participants (attrition). RESULTS:Acceptance: In focus groups, residents (n=17) reported leaderboards were the most important motivator of participation. Use: 16 427 questions were completed: 28.8% on Saturdays/Sundays, 53.1% between 17:00 and 08:00. Retention of knowledge: 1046 paired responses (for repeated questions) were collected. Correct responses increased by 11.9% (p<0.0001) on retest. Differences per time since question introduction, trainee level and style of play were observed. Attrition: In ordinal regression analyses, completing more questions (0.80 per 10% increase; 0.70 to 0.93) decreased, while postgraduate year 3 class (4.25; 1.44 to 12.55) and non-daily play (4.51; 1.50 to 13.58) increased odds of attrition. CONCLUSIONS:Our software-enabled, gamification-based educational intervention was well accepted among our millennial learners. Coupling software with gamification and analysis of trainee use and engagement data can be used to develop strategies to augment learning in time-constrained educational settings.