Utilization of Left Ventricular Assist Devices in Vulnerable Adults Across Medicaid Expansion.

BACKGROUND: Continuous-flow left ventricular assist device (LVAD) implantation is a payor sensitive procedure influenced by preoperative comorbidities and social factors. Whether expansion in insurance coverage will further influence device utilization is unknown. This study sought to assess the effects of Medicaid expansion on vulnerable populations (namely racial-ethnic minorities and those with low-income status) undergoing continuous-flow LVAD implantation after the enactment of the 2014 Affordable Care Act (ACA). METHODS: Data from the 2012 to Q3 2015 State Inpatient Database were used to examine a cohort of 624 nonelderly adults (aged 18-64 y) who were given a continuous-flow LVAD in three expansion states (Kentucky, New Jersey, and Maryland) and two nonexpansion states (North Carolina and Florida). The cohort excluded patients who had a heart transplant, heart-lung transplant, or noncontinuous-flow LVAD. Poisson Interrupted Time Series was used with three-way interactions and change of slope and intercept parameters at 2014 to determine the impact of the ACA expansion on utilization of continuous-flow LVAD by race and insurance strata. RESULTS: Poisson Interrupted Time Series models show that within expansion states, the population of Medicaid and uninsured patients saw an increase in the utilization of LVAD's immediately after ACA expansion, from 2.8 in Q4 2013 to 9.83 Q1 2014 (incidence rate ratio [IRR] 5.26, P = 0.02). Utilization eventually declined to pre-ACA levels, however, ending with 3.04 LVADs in Q3 2015 (IRR 0.84, 95% confidence interval 0.58-1.20). Models testing for racial effect showed no statistically preferential or disparate effects (immediate effect IRR 1.608, P = 0.506; marginal effect IRR 0.897, P = 0.512). CONCLUSIONS: These findings show that despite expanded insurance coverage, the utilization of continuous-flow LVADs was not increased in nonelderly racial and ethnic minorities following the ACA Medicaid expansion. Although these findings are preliminary and require further long-term evaluation, they suggest that insurance coverage alone does not play a significant role in increased utilization of continuous-flow LVAD. These findings point toward the importance of further exploring social, medical, and hospital drivers of these disparities.

Cardiac function in BRCA1/2 mutation carriers with history of breast cancer treated with anthracyclines.

Animal data suggest that defects in BRCA1/2 genes significantly increase the risk of heart failure and mortality in mice exposed to doxorubicine. Women with BRCA1/2 mutations who develop breast cancer (BC) may receive anthracyclines but their risk of cardiac dysfunction has not been investigated. Our study tested the hypothesis that women with history of BRCA1/2 mutation-associated BC treated with anthracyclines have impaired parameters of cardiac function compared to similarly treated women with history of sporadic BC. Women with history of BC and anthracycline treatment underwent an echocardiographic exam for assessment of primary outcomes, left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS). The sample size of 81 provided 79 % power with two-sided two-sample t test and alpha of 0.05 to detect a clinically meaningful difference in cardiac function of absolute 5 % points difference for LVEF and 2 % points difference for GLS. Of 81 normotensive participants, 39 were BRCA1/2 mutation carriers and 42 in the sporadic group. Mean age was 50 ± 9 years in both groups (P = 0.99) but BRCA1/2 mutation carriers had longer anthracycline treatment-to-enrollment time (7.5 ± 5.3 vs. 4.2 ± 3.3 years, P = 0.001). There were no significant differences in LVEF (P = 0.227) or GLS (P = 0.53) between the groups. LVEF was normal in 91 % of women and subclinical cardiac dysfunction defined as absolute GLS value <18.9 % was seen in 4 (10 %) BRCA1/2 mutation carriers and 7 (17 %) sporadic participants. In this first prospective examination of cardiac function in BRCA1/2 mutation carriers, we found no significant differences in sensitive echocardiographic parameters of cardiac function between BRCA1/2 mutation carriers and women with history of sporadic BC who received anthracycline treatment. In contrast to laboratory animal data, our findings indicate lack of elevated cardiac risk with the use of standard-doses of adjuvant anthracyclines in treatment of BRCA1/2 mutation carriers with early stage BC.

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

BACKGROUND: Kidney disease disproportionately affects minority populations, including African Americans and Hispanics; therefore, understanding the relationship of kidney function to cardiovascular (CV) outcomes within different racial/ethnic groups is of considerable interest. We investigated the relationship between kidney function and CV events and assessed effect modification by race/ethnicity in the Women's Health Initiative. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: Baseline serum creatinine concentrations (assay traceable to isotope-dilution mass spectrometry standard) of 19,411 postmenopausal women aged 50 to 79 years who self-identified as either non-Hispanic white (n=8,921), African American (n=7,436), or Hispanic (n=3,054) were used to calculate estimated glomerular filtration rates (eGFRs). PREDICTORS: Categories of eGFR (exposure); race/ethnicity (effect modifier). OUTCOMES: The primary outcome was the composite of 3 physician-adjudicated CV events: myocardial infarction, stroke, or CV-related death. MEASUREMENTS: We evaluated the multivariable-adjusted associations between categories of eGFR and CV events using proportional hazards regression and formally tested for effect modification by race/ethnicity. RESULTS: During a mean follow-up of 7.6 years, 1,424 CV events (653 myocardial infarctions, 627 strokes, and 297 CV-related deaths) were observed. The association between eGFR and CV events was curvilinear; however, the association of eGFR with CV outcomes differed by race (P=0.006). In stratified analyses, we observed that the U-shaped association was present in non-Hispanic whites, whereas African American participants had a rather curvilinear relationship, with lower eGFR being associated with higher CV risk, and higher eGFR, with reduced CV risk. Analyses among Hispanic women were inconclusive owing to few Hispanic women having very low or high eGFRs and very few events occurring in these categories. LIMITATIONS: Lack of urinary albumin measurements; residual confounding by unmeasured or imprecisely measured characteristics. CONCLUSIONS: In postmenopausal women, the patterns of association between eGFR and CV risk differed between non-Hispanic whites and African American women.

Travel patterns of cancer surgery patients in a regionalized system.

BACKGROUND: Regionalization of complex surgeries has increased patient travel distances possibly leaving a substantial burden on those at risk for poorer surgical outcomes. To date, little is known about travel patterns of cancer surgery patients in regionalized settings. To inform this issue, we sought to assess travel patterns of those undergoing a major cancer surgery within a regionalized system. MATERIALS AND METHODS: We identified 4733 patients who underwent lung, esophageal, gastric, liver, pancreatic, and colorectal resections from 2002-2014 within a multihospital system in the Mid-Atlantic region of the United States. Patient age, race and/or ethnicity, and insurance status were extracted from electronic health records. We used Geographical Information System capabilities in R software to estimate travel distance and map patient addresses based on cancer surgery type and these characteristics. We used visual inspection, analysis of variance, and interaction analyses to assess the distribution of travel distances between patient populations. RESULTS: A total of 48.2% of patients were non-white, 49.9% were aged >65 y, and 54.9% had private insurance. Increased travel distance was associated with decreasing age and those undergoing pancreatic and esophageal resections. Also, black patients tend to travel shorter distances than other racial and/or ethnic groups. CONCLUSIONS: These maps offer a preliminary understanding into variations of geospatial travel patterns among patients receiving major cancer surgery in a Mid-Atlantic regionalized setting. Future research should focus on the impact of regionalization on timely delivery of surgical care and other quality metrics.

Activity, energy intake, obesity, and the risk of incident kidney stones in postmenopausal women: a report from the Women's Health Initiative.

Obesity is a strong risk factor for nephrolithiasis, but the role of physical activity and caloric intake remains poorly understood. We evaluated this relationship in 84,225 women with no history of stones as part of the Women's Health Initiative Observational Study, a longitudinal, prospective cohort of postmenopausal women enrolled from 1993 to 1998 with 8 years' median follow-up. The independent association of physical activity (metabolic equivalents [METs]/wk), calibrated dietary energy intake, and body mass index (BMI) with incident kidney stone development was evaluated after adjustment for nephrolithiasis risk factors. Activity intensity was evaluated in stratified analyses. Compared with the risk in inactive women, the risk of incident stones decreased by 16% in women with the lowest physical activity level (adjusted hazard ratio [aHR], 0.84; 95% confidence interval [95% CI], 0.74 to 0.97). As activity increased, the risk of incident stones continued to decline until plateauing at a decrease of approximately 31% for activity levels ≥10 METs/wk (aHR, 0.69; 95% CI, 0.60 to 0.79). Intensity of activity was not associated with stone formation. As dietary energy intake increased, the risk of incident stones increased by up to 42% (aHR, 1.42; 95% CI, 1.02 to 1.98). However, intake <1800 kcal/d did not protect against stone formation. Higher BMI category was associated with increased risk of incident stones. In summary, physical activity may reduce the risk of incident kidney stones in postmenopausal women independent of caloric intake and BMI, primarily because of the amount of activity rather than exercise intensity. Higher caloric intake further increases the risk of incident stones.

Association of chronic kidney disease with cerebral microbleeds in patients with primary intracerebral hemorrhage.

BACKGROUND AND PURPOSE: To investigate the relationship between chronic kidney disease (CKD) and MRI-defined cerebral microbleeds (CMB), a harbinger of future intracerebral hemorrhage (ICH), among patients with a recent history of primary ICH. METHODS: Using data from a predominantly black cohort of patients with a recent ICH-enrolled in an observational study between September 2007 and June 2011, we evaluated the association between CKD (defined as estimated low glomerular filtration rate<60 mL/min per 1.73 m(2)) and CMB on gradient-echo MRI. Multivariable models were generated to determine the contribution of CKD to the presence, number, and location of CMB. RESULTS: Of 197 subjects with imaging data, mean age was 59 years, 48% were women, 73% were black, 114 (58%) had ≥1 CMBs, and 52 (26%) had CKD. Overall, CKD was associated with presence of CMB (adjusted odds ratio, 2.70; 95% confidence interval [CI], 1.10-6.59) and number of CMB (adjusted relative risk, 2.04; 95% CI, 1.27-3.27). CKD was associated with CMB presence (adjusted odds ratio, 3.44; 95% CI, 1.64-7.24) and number (adjusted relative risk, 2.46; 95% CI, 1.11-5.42) in black patients, but not CMB presence (adjusted odds ratio, 3.00; 95% CI, 0.61-14.86) or number (adjusted relative risk, 1.03; 95% CI: 0.22-4.89) in non-Hispanic white patients (interactions by race were statistically not significant). CONCLUSIONS: CKD is associated with a greater presence and number of CMB in ICH patients, particularly in patients of black race. Future studies should assess whether low estimated glomerular filtration rate may be a CMB risk marker or potential therapeutic target for mitigating the development of CMB.

Predictors of highly prevalent brain ischemia in intracerebral hemorrhage.

OBJECTIVE: This study was undertaken to determine the prevalence, characteristics, risk factors, and temporal profile of concurrent ischemic lesions in patients with acute primary intracerebral hemorrhage (ICH). METHODS: Patients were recruited within a prospective, longitudinal, magnetic resonance imaging (MRI)-based study of primary ICH. Clinical, demographic, and MRI data were collected on all subjects at baseline and 1 month. RESULTS: Of the 138 patients enrolled, mean age was 59 years, 54% were male, 73% were black, and 84% had a history of hypertension. At baseline, ischemic lesions on diffusion-weighted imaging (DWI) were found in 35% of patients. At 1 month, lesions were present in 27%, and of these lesions, 83% were new and not present at baseline. ICH volume (p = 0.025), intraventricular hemorrhage (p = 0.019), presence of microbleeds (p = 0.024), and large, early reductions in mean arterial pressure (p = 0.003) were independent predictors of baseline DWI lesions. A multivariate logistical model predicting the presence of 1-month DWI lesions included history of any prior stroke (p = 0.012), presence of 1 or more microbleeds (p = 0.04), black race (p = 0.641), and presence of a DWI lesion at baseline (p = 0.007). INTERPRETATION: This study demonstrates that >⅓ of patients with primary ICH have active cerebral ischemia at baseline remote from the index hematoma, and » of patients experience ongoing, acute ischemic events at 1 month. Multivariate analyses implicate blood pressure reductions in the setting of an active vasculopathy as a potential underlying mechanism. Further studies are needed to determine the impact of these lesions on outcome and optimal management strategies to arrest vascular damage.

Poor long-term blood pressure control after intracerebral hemorrhage.

BACKGROUND AND PURPOSE: Hypertension is the most important risk factor associated with intracerebral hemorrhage. We explored racial differences in blood pressure (BP) control after intracerebral hemorrhage and assessed predictors of BP control at presentation, 30 days, and 1 year in a prospective cohort study. METHODS: Subjects with spontaneous intracerebral hemorrhage were identified from the DiffErenCes in the Imaging of Primary Hemorrhage based on Ethnicity or Race (DECIPHER) Project. BP was compared by race at each time point. Multivariable linear regression was used to determine predictors of presenting mean arterial pressure, and longitudinal linear regression was used to assess predictors of mean arterial pressure at follow-up. RESULTS: A total of 162 patients were included (mean age, 59 years; 53% male; 77% black). Mean arterial pressure at presentation was 9.6 mm Hg higher in blacks than whites despite adjustment for confounders (P=0.065). Fewer than 20% of patients had normal BP (<120/80 mm Hg) at 30 days or 1 year. Although there was no difference at 30 days (P=0.331), blacks were more likely than whites to have Stage I/II hypertension at 1 year (P=0.036). Factors associated with lower mean arterial pressure at follow-up in multivariable analysis were being married at baseline (P=0.032) and living in a facility (versus personal residence) at the time of BP measurement (P=0.023). CONCLUSIONS: Long-term BP control is inadequate in patients after intracerebral hemorrhage, particularly in blacks. Further studies are needed to understand the role of social support and barriers to control to identify optimal approaches to improve BP in this high-risk population.

Arsenic exposure, diabetes prevalence, and diabetes control in the Strong Heart Study.

This study evaluated the association of arsenic exposure, as measured in urine, with diabetes prevalence, glycated hemoglobin, and insulin resistance in American Indian adults from Arizona, Oklahoma, and North and South Dakota (1989-1991). We studied 3,925 men and women 45-74 years of age with available urine arsenic measures. Diabetes was defined as a fasting glucose level of 126 mg/dL or higher, a 2-hour glucose level of 200 mg/dL or higher, a hemoglobin A1c (HbA1c) of 6.5% or higher, or diabetes treatment. Median urine arsenic concentration was 14.1 µg/L (interquartile range, 7.9-24.2). Diabetes prevalence was 49.4%. After adjustment for sociodemographic factors, diabetes risk factors, and urine creatinine, the prevalence ratio of diabetes comparing the 75th versus 25th percentiles of total arsenic concentrations was 1.14 (95% confidence interval: 1.08, 1.21). The association between arsenic and diabetes was restricted to participants with poor diabetes control (HbA1c ≥8%). Arsenic was positively associated with HbA1c levels in participants with diabetes. Arsenic was not associated with HbA1c or with insulin resistance (assessed by homeostatic model assessment to quantify insulin resistance) in participants without diabetes. Urine arsenic was associated with diabetes control in a population from rural communities in the United States with a high burden of diabetes. Prospective studies that evaluate the direction of the relation between poor diabetes control and arsenic exposure are needed.

The association of genetic variants of type 2 diabetes with kidney function.

Type 2 diabetes is highly prevalent and is the major cause of progressive chronic kidney disease in American Indians. Genome-wide association studies identified several loci associated with diabetes but their impact on susceptibility to diabetic complications is unknown. We studied the association of 18 type 2 diabetes genome-wide association single-nucleotide polymorphisms (SNPs) with estimated glomerular filtration rate (eGFR; MDRD equation) and urine albumin-to-creatinine ratio in 6958 Strong Heart Study family and cohort participants. Center-specific residuals of eGFR and log urine albumin-to-creatinine ratio, obtained from linear regression models adjusted for age, sex, and body mass index, were regressed onto SNP dosage using variance component models in family data and linear regression in unrelated individuals. Estimates were then combined across centers. Four diabetic loci were associated with eGFR and one locus with urine albumin-to-creatinine ratio. A SNP in the WFS1 gene (rs10010131) was associated with higher eGFR in younger individuals and with increased albuminuria. SNPs in the FTO, KCNJ11, and TCF7L2 genes were associated with lower eGFR, but not albuminuria, and were not significant in prospective analyses. Our findings suggest a shared genetic risk for type 2 diabetes and its kidney complications, and a potential role for WFS1 in early-onset diabetic nephropathy in American Indian populations.

Estimated GFR and incident cardiovascular disease events in American Indians: the Strong Heart Study.

BACKGROUND: In populations with high prevalences of diabetes and obesity, estimating glomerular filtration rate (GFR) by using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation may predict cardiovascular disease (CVD) risk better than by using the Modification of Diet in Renal Disease (MDRD) Study equation. STUDY DESIGN: Longitudinal cohort study comparing the association of GFR estimated using either the CKD-EPI or MDRD Study equation with incident CVD outcomes. SETTING & PARTICIPANTS: American Indians participating in the Strong Heart Study, a longitudinal population-based cohort with high prevalences of diabetes, CVD, and CKD. PREDICTOR: Estimated GFR (eGFR) predicted using the CKD-EPI and MDRD Study equations. OUTCOMES: Fatal and nonfatal cardiovascular events, consisting of coronary heart disease, stroke, and heart failure. MEASUREMENTS: The association between eGFR and outcomes was explored in Cox proportional hazards models adjusted for traditional risk factors and albuminuria; the net reclassification index and integrated discrimination improvement were determined for the CKD-EPI versus MDRD Study equations. RESULTS: In 4,549 participants, diabetes was present in 45%; CVD, in 7%; and stages 3-5 CKD, in 10%. During a median of 15 years, there were 1,280 cases of incident CVD, 929 cases of incident coronary heart disease, 305 cases of incident stroke, and 381 cases of incident heart failure. Reduced eGFR (<90 mL/min/1.73 m2) was associated with adverse events in most models. Compared with the MDRD Study equation, the CKD-EPI equation correctly reclassified 17.0% of 2,151 participants without incident CVD to a lower risk (higher eGFR) category and 1.3% (n=28) were reclassified incorrectly to a higher risk (lower eGFR) category. LIMITATIONS: Single measurements of eGFR and albuminuria at study visits. CONCLUSIONS: Although eGFR based on either equation had similar associations with incident CVD, coronary heart disease, stroke, and heart failure events, in those not having events, reclassification of participants to eGFR categories was superior using the CKD-EPI equation compared with the MDRD Study equation.

EEG screening for temporal lobe epilepsy in patients with acute psychosis.

Seizures may present with ictal or interictal psychosis mimicking primary psychiatric disorders. The authors reviewed EEG, brain-imaging, and clinical data of 240 patients presenting with acute psychotic episode to assess the diagnostic value of EEG in differentiating ictal psychosis from primary psychosis. Seven patients had interictal spikes, but there were no patients with ictal discharges. There were no significant associations between the tested variables except that taking neuroleptics/antidepressants was associated with abnormal EEG, and older age and taking anti-epileptic drugs were associated with abnormal CT scans. These findings do not support routine use of EEG in patients presenting with acute psychosis.

Increased Access to Cardiac Surgery Did Not Improve Outcomes: Early Look Into Medicaid Expansion.

BACKGROUND: Cardiac surgery utilization has increased after passage of the Affordable Care Act. This multistate study examined whether changes in access after Medicaid expansion (ME) have led to improved outcomes, overall and particularly among ethnoracial minorities. METHODS: State Inpatient Databases were used to identify nonelderly adults (ages 18-64 years) who underwent coronary artery bypass grafting, aortic valve replacement, mitral valve replacement, or mitral valve repair in 3 expansion (Kentucky, New Jersey, Maryland) vs 2 nonexpansion states (North Carolina, Florida) from 2012 to 2015. Linear and logistic interrupted time series were used with 2-way interactions and adjusted for patient-level, hospital-level, and county-level factors to compare trends and instantaneous changes at the point of ME implementation (quarter 1 of 2014) for mortality, length of stay, and elective status. Interrupted time series models estimated expansion effect, overall and by race-ethnicity. RESULTS: Analysis included 22 038 cardiac surgery patients from expansion states and 33 190 from nonexpansion states. In expansion states, no significant trend changes were observed for mortality (odds ratio, 1.01; P = .83) or length of stay (ß = -0.05, P = .20), or for elective surgery (odds ratio, 1.00; P = .91). There were similar changes seen in nonexpansion states. Among ethnoracial minorities, ME did not impact outcomes or elective status. CONCLUSIONS: Despite an increase in cardiac surgery utilization after ME, outcomes remained unchanged in the early period after implementation, overall and among ethnoracial minorities. Future research is needed to confirm long-term trends and examine reasons behind this lack of improved outcomes.

Rate of Force Development Is Related to Maximal Force and Sit-to-Stand Performance in Men With Stages 3b and 4 Chronic Kidney Disease.

INTRODUCTION: The primary aims of the present study were to assess the relationships of early (0-50 ms) and late (100-200 ms) knee extensor rate of force development (RFD) with maximal voluntary force (MVF) and sit-to-stand (STS) performance in participants with chronic kidney disease (CKD) not requiring dialysis. METHODS: Thirteen men with CKD (eGFR = 35.17 ±.5 ml/min per 1.73 m2, age = 70.56 ±.4 years) and 12 non-CKD men (REF) (eGFR = 80.31 ± 4.8 ml/min per 1.73 m2, age = 70.22 ±.9 years) performed maximal voluntary isometric contractions to determine MVF and RFD of the knee extensors. RFD was measured at time intervals 0-50 ms (RFD0-50) and 100-200 ms (RFD100-200). STS was measured as the time to complete five repetitions. Measures of rectus femoris grayscale (RF GSL) and muscle thickness (RF MT) were obtained via ultrasonography in the CKD group only. Standardized mean differences (SMD) were used to examine differences between groups. Bivariate relationships were assessed by Pearson's product moment correlation. RESULTS: Knee extensor MVF adjusted for body weight (CKD=17.14 ±.1 N·kg0.67, REF=21.55 ±.3 N·kg0.67, SMD = 0.79) and STS time (CKD = 15.93 ±.4 s, REF = 12.23 ±.7 s, SMD = 1.03) were lower in the CKD group than the REF group. Absolute RFD100-200 was significantly directly related to adjusted MVF in CKD (r = 0.56, p = 0.049) and REF (r = 0.70, p = 0.012), respectively. STS time was significantly inversely related to absolute (r = -0.75, p = 0.008) and relative RFD0-50 (r = -0.65, p = 0.030) in CKD but not REF (r = 0.08, p = 0.797; r = 0.004, p = 0.991). Significant inverse relationships between RF GSL adjusted for adipose tissue thickness and absolute RFD100-200 (r =-0.59, p = 0.042) in CKD were observed. CONCLUSION: The results of the current study highlight the declines in strength and physical function that occur in older men with CKD stages 3b and 4 not requiring dialysis. Moreover, early RFD was associated with STS time in CKD while late RFD was associated MVF in both CKD and REF. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT03160326 and NCT02277236.

Cardiac Surgery Utilization Across Vulnerable Persons After Medicaid Expansion.

BACKGROUND: Medicaid expansion (ME) under the Affordable Care Act has reduced the number of uninsured patients, although its preferential effects on vulnerable populations have been mixed. This study examined whether ME preferentially improved cardiac surgery use by insurance strata, race, and income level. METHODS: Non-elderly adults (aged 18-64 years) who underwent coronary artery bypass grafting, aortic valve replacement, mitral valve replacement, or mitral valve repair were identified in the State Inpatient Databases for 3 expansion states (Kentucky, New Jersey, and Maryland) and 2 non-expansion states (North Carolina and Florida) from 2012 to the third quarter of 2015. We used adjusted Poisson interrupted time series to determine the impact of ME on cardiac surgery use for Medicaid or uninsured (MCD/UIS) patients, racial and ethnic minorities, and individuals from low-income areas. RESULTS: In expansion states, use among non-White MCD/UIS patients had a positive trend after ME (2.3%/quarter; P = .156), whereas use for White MCD/UIS patients fell (-1.7%/quarter; P = .117). In contrast, use among non-White MCD/UIS in non-expansion states decreased by 4.4% (P < .001) which was a greater decline than among White MCD/UIS patients (-1.8%/quarter; P = .057). There was no substantial effect of ME on cardiac surgery use for MCD/UIS patients from low- versus high-income areas. CONCLUSIONS: These findings demonstrate that the use of cardiac surgical procedures was generally unchanged after ME; however, nonsignificant trend differences suggest a narrowing gap between vulnerable and non-vulnerable groups in ME states. These preliminary findings help describe the association of insurance coverage as a driver of cardiac surgery use among vulnerable patients.

Incidence rates and predictors of diabetes in those with prediabetes: the Strong Heart Study.

BACKGROUND: The association between prediabetes as currently defined and incident diabetes in populations with widespread obesity, insulin resistance syndrome, and diabetes is not well defined. In this article, diabetes risk factors and incidence rates in American Indians (AI) with prediabetes are examined. METHODS: A total of 1677 AI who were nondiabetic at baseline was examined during a median 7.8-year follow-up as part of the Strong Heart Study (SHS). Risk factors for incident diabetes were measured. Prediabetes was defined according to American Diabetes Association 2003 criteria as having impaired glucose tolerance (IGT) (2-h plasma glucose [2-h PG] >or= 140 mg/dL but < 200 mg/dL) and/or impaired fasting glucose (IFG) (fasting plasma glucose [FPG] >or= 100 mg/dL but < 126 mg/dL). RESULTS: Prediabetes was identified by FPG alone in 87.5%. Diabetes incidence in those with baseline prediabetes was 66.1/1000 person-years, with a hazard ratio (HR) of 2.35 (95% conference interval: 1.84-3.01), compared with participants with normal glucose tolerance (NGT) at baseline. Elevated A(1c), 2-h PG, and fasting insulin (FI); albuminuria; and obesity were significantly associated with conversion from prediabetes to diabetes. Younger age, elevated FI (or body mass index [BMI] in models without FI), and less physical activity were significantly associated with conversion from NGT. CONCLUSIONS: Prediabetes is an independent predictor of conversion to type 2 diabetes in AI, and most can be identified through a fasting glucose measure. Measures of obesity, A(1c), FPG, 2-h PG, FI, albuminuria, and insulin resistance (IR) help predict this conversion. Obesity is a modifiable risk factor. Strategies to reduce obesity should be emphasized in individuals with prediabetes.

Models of population-based analyses for data collected from large extended families.

Large studies of extended families usually collect valuable phenotypic data that may have scientific value for purposes other than testing genetic hypotheses if the families were not selected in a biased manner. These purposes include assessing population-based associations of diseases with risk factors/covariates and estimating population characteristics such as disease prevalence and incidence. Relatedness among participants however, violates the traditional assumption of independent observations in these classic analyses. The commonly used adjustment method for relatedness in population-based analyses is to use marginal models, in which clusters (families) are assumed to be independent (unrelated) with a simple and identical covariance (family) structure such as those called independent, exchangeable and unstructured covariance structures. However, using these simple covariance structures may not be optimally appropriate for outcomes collected from large extended families, and may under- or over-estimate the variances of estimators and thus lead to uncertainty in inferences. Moreover, the assumption that families are unrelated with an identical family structure in a marginal model may not be satisfied for family studies with large extended families. The aim of this paper is to propose models incorporating marginal models approaches with a covariance structure for assessing population-based associations of diseases with their risk factors/covariates and estimating population characteristics for epidemiological studies while adjusting for the complicated relatedness among outcomes (continuous/categorical, normally/non-normally distributed) collected from large extended families. We also discuss theoretical issues of the proposed models and show that the proposed models and covariance structure are appropriate for and capable of achieving the aim.

Decreased GFR estimated by MDRD or Cockcroft-Gault equation predicts incident CVD: the strong heart study.

BACKGROUND: Kidney function, expressed as glomerular filtration rate (GFR), is commonly estimated from serum creatinine (Scr) and, when decreased, may serve as a nonclassical risk factor for incident cardiovascular disease (CVD). The ability of estimated GFR (eGFR) to predict CVD events during 5-10 years of follow-up is assessed using data from the Strong Heart Study (SHS), a large cohort with a high prevalence of diabetes. METHODS: eGFRs were calculated with the abbreviated Modification of Diet in Renal Disease study (MDRD) and the Cockcroft-Gault (CG) equations. These estimates were compared in participants with normal and abnormal Scr. The association between eGFR and incident CVD was assessed. RESULTS: More subjects were labeled as having low eGFR (<60 ml/min per 1.73 m2) by the MDRD or CG equation, than by Scr alone. When Scr was in the normal range, both equations labeled similar numbers of participants as having low eGFRs, although concordance between the equations was poor. However, when Scr was elevated, the MDRD equation labeled more subjects as having low eGFR. Persons with low eGFR had increased risk of CVD. CONCLUSIONS: The MDRD and CG equations labeled more participants as having decreased GFR than did Scr alone. Decreased eGFR was predictive of CVD in this American Indian population with a high prevalence of obesity and type 2 diabetes mellitus.

Hyponatremia Is Associated With Increased Osteoporosis and Bone Fractures in Patients With Diabetes With Matched Glycemic Control.

CONTEXT: Patients with diabetes mellitus are at increased risk for bone fragility fracture secondary to multiple mechanisms. Hyperglycemia can induce true dilutional hyponatremia. Hyponatremia is associated with gait instability, osteoporosis, and increased falls and bone fractures, and studies suggest that compromised bone quality with hyponatremia may be independent of plasma osmolality. We performed a case-control study of patients with diabetes mellitus matched by median glycated hemoglobin (HbA1c) to assess whether hyponatremia was associated with increased risk of osteoporosis and/or fragility fracture. DESIGN: Osteoporosis (n = 823) and fragility fracture (n = 840) cases from the MedStar Health database were matched on age of first HbA1c ≥6.5%, sex, race, median HbA1c over an interval from first HbA1c ≥6.5% to the end of the encounter window, diabetic encounter window length, and type 1 vs type 2 diabetes mellitus with controls without osteoporosis (n = 823) and without fragility fractures (n = 840), respectively. Clinical variables, including coefficient of glucose variation and hyponatremia (defined as serum [Na+] <135 mmol/dL within 30 days of the end of the diabetic window), were included in a multivariate analysis. RESULTS: Multivariate conditional logistic regression models demonstrated that hyponatremia within 30 days of the outcome measure was independently associated with osteoporosis and fragility fractures (osteoporosis OR 3.09; 95% CI, 1.37 to 6.98; fracture OR, 6.41; 95% CI, 2.44 to 16.82). CONCLUSIONS: Our analyses support the hypothesis that hyponatremia is an additional risk factor for osteoporosis and fragility fracture among patients with diabetes mellitus.