Performance of contemporary cardiovascular risk stratification scores in Brazil: an evaluation in the ELSA-Brasil study.

AIMS: Despite notable population differences in high-income and low- and middle-income countries (LMICs), national guidelines in LMICs often recommend using US-based cardiovascular disease (CVD) risk scores for treatment decisions. We examined the performance of widely used international CVD risk scores within the largest Brazilian community-based cohort study (Brazilian Longitudinal Study of Adult Health, ELSA-Brasil). METHODS: All adults 40-75 years from ELSA-Brasil (2008-2013) without prior CVD who were followed for incident, adjudicated CVD events (fatal and non-fatal MI, stroke, or coronary heart disease death). We evaluated 5 scores-Framingham General Risk (FGR), Pooled Cohort Equations (PCEs), WHO CVD score, Globorisk-LAC and the Systematic Coronary Risk Evaluation 2 score (SCORE-2). We assessed their discrimination using the area under the receiver operating characteristic curve (AUC) and calibration with predicted-to-observed risk (P/O) ratios-overall and by sex/race groups. RESULTS: There were 12 155 individuals (53.0±8.2 years, 55.3% female) who suffered 149 incident CVD events. All scores had a model AUC>0.7 overall and for most age/sex groups, except for white women, where AUC was <0.6 for all scores, with higher overestimation in this subgroup. All risk scores overestimated CVD risk with 32%-170% overestimation across scores. PCE and FGR had the highest overestimation (P/O ratio: 2.74 (95% CI 2.42 to 3.06)) and 2.61 (95% CI 1.79 to 3.43)) and the recalibrated WHO score had the best calibration (P/O ratio: 1.32 (95% CI 1.12 to 1.48)). CONCLUSION: In a large prospective cohort from Brazil, we found that widely accepted CVD risk scores overestimate risk by over twofold, and have poor risk discrimination particularly among Brazilian women. Our work highlights the value of risk stratification strategies tailored to the unique populations and risks of LMICs.

Measurement properties of Portuguese-Brazil Western Ontario and McMaster Universities osteoarthritis index (WOMAC) for the assessment of knee complaints in Brazilian adults: ELSA-Brasil Musculoskeletal cohort.

Information on measurement properties of translated versions of the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index is still limited. This study investigated the internal consistency, test-retest reliability/agreement, construct validity, and floor and ceiling effects of Portuguese-Brazil WOMAC applied to civil servants at baseline of ELSA-Brasil Musculoskeletal cohort. Each measurement property was evaluated in the overall sample, in the subgroup reporting knee symptoms, and across different sociodemographic strata (except factorial analyses). Separate analyses were performed for pain, stiffness and function dimensions, considering the knee with the worst score (or right knee if same score in both knees). A total of 1740 participants were included (319 completed WOMAC on 2 occasions), mean age 56.0 (standard deviation = 8.9) years, 46.8% male, 42.1% had knee symptoms. In the overall sample, the range of results for WOMAC's dimensions were: internal consistency = cronbach alpha 0.92-0.98; test-retest reliability = intraclass correlation coefficient 0.85-0.97; standard error of measurement (SEM) = 1.38-5.86; smallest detectable change (SDC) = 3.84-16.25; lowest possible score = 38.8%-61.1% (floor effect present); highest possible score = 0.2%-0.9% (ceiling effect absent). Construct validity was confirmed by hypothesis testing and factorial analysis. Results were similar in the symptomatic group, except for higher SEM and SDC, and the absence of floor effects in pain and function dimensions. Portuguese-Brazil WOMAC showed good overall quality in a nonclinical setting. Variability in measurement properties across different strata of the population should be taken into consideration for the design of future studies using WOMAC.

Prevalence of the metabolic syndrome using two proposed definitions in a Japanese-Brazilians community.

Metabolic Syndrome (MetS) is associated with increased risk of morbi-mortality, thus the characterization of the population magnitude of this syndrome is critical for allocating health care. However, prevalence estimates of MetS in the same population could differ depending on the definition used. Therefore, we compared the prevalence of the MetS using definitions proposed by: National Cholesterol Education Panel Revised (NCEP) and International Diabetes Federation (IDF) 2009 in a Japanese-Brazilians community (131 individuals, age 57 ± 16 years, 1st and 2nd generation). All individuals went through a clinical and laboratorial evaluation for assessment of weigh, height, waist circumference, blood pressure, triglycerides, HDL-cholesterol and fasting plasma glucose. The prevalence of MetS was 26.7% (n = 35) and 37.4% (n = 49) under the NCEP and IDF definitions, respectively. Despite higher blood pressure measurements, waist circumference and serum triglyceride levels and lower HDL cholesterol levels (p < 0.01), individuals identified with MetS did not show increased blood glucose levels. IDF definition classified 14 individuals (10.7%) with MetS that were not classified under the NCEP and 35 individuals were identified with MetS by both criteria. We observed, in this group, more severe lipid disorders, compared to individuals identified only under the IDF definition, and the BMI and waist circumference (p = 0.01; p = 0.006, respectively) were lower. In conclusion, the IDF revised criteria, probably because of the ethnic specific values of waist circumference, was able to identify a larger number of individuals with MetS. However, our data suggesting that additional studies are necessary to define best MetS diagnostic criteria in this population.

Relationship between ABO blood groups and von Willebrand factor, ADAMTS13 and factor VIII in patients undergoing hemodialysis.

Several studies have demonstrated that non-O blood groups subjects present an increased VTE risk as compared to those carrying O blood group. The aim of this study was to investigate the ABO blood groups influence on factor VIII (FVIII) activity, von Willebrand factor (VWF), and ADAMTS13 plasma levels in patients undergoing hemodialysis (HD). Patients undergoing HD (N=195) and 80 healthy subjects (control group) were eligible for this cross-sectional study. The ABO blood group phenotyping was performed by the reverse technique. FVIII activity was measured through coagulometric method, and VWF and ADAMTS13 antigens were assessed by ELISA. FVIII activity and VWF levels were significantly higher and ADAMTS13 levels was decreased in HD patients, as compared to healthy subjects (P < 0.001, in three cases). HD patients carrying non-O blood groups showed a significant increase in FVIII activity (P = 0.001) and VWF levels (P < 0.001) when compared to carriers of O blood group. However, no significant difference was observed in ADAMTS13 levels (P = 0.767). In the control group, increased in FVIII activity (P = 0.001) and VWF levels (P = 0.002) and decreased in ADAMTS13 levels (P = 0.005) were observed in subjects carrying non-O blood groups as compared to carriers of O blood group.Our data confirmed that ABO blood group is an important risk factor for increased procoagulant factors in plasma, as FVIII and VWF. Admitting the possible role of kidneys in ADAMTS13 synthesis or on its metabolism, HD patients were not able to increase ADAMTS13 levels in order to compensate the increase of VWF levels mediated by ABO blood groups. Considering that non-O blood groups constitute a risk factor for thrombosis, it is reasonable to admit that A, B and AB HD patients need a careful and continuous follow-up in order to minimize thrombotic events.

ADAMTS13 and Von Willebrand factor in patients undergoing hemodialysis.

Hemodialysis (HD) is associated with increasing thrombotic trend. Vascular access thrombosis (VAT) increases morbidity in HD patients. The aim of this study was to evaluate ADAMTS13 and VWF plasma levels from patients undergoing HD as putative biomarkers of the hypercoagulability state, as well the association between these markers and VAT occurrence. This study included 195 patients on HD for more than 6 months. HD patients were allocated into two groups according to the occurrence or not of previous episode of VAT; HD with VAT (N = 46) and HD without VAT (N = 149). ADAMTS13 and VWF were performed by ELISA. There was no significant difference between HD patients with and without VAT for ADAMTS13 and VWF levels. However, VWF levels were higher (P < 0.001) and ADAMTS13 were lower (P < 0.001) in HD patients, comparing to the control group composed by healthy subjects without kidney disease, age and sex-matched (N = 80). Taken together our data suggest a potential role of the kidneys function compromised on ADAMTS13 synthesis or metabolism, regardless other known sources of ADAMTS13. The imbalance between ADAMTS13 and VWF levels does not explain the development of VAT in HD patients by itself, although it should contribute for the hypercoagulability state. Therefore, additional studies to identify other risk factors are warranted and essential for better management of HD patients.

Hemodialysis vascular access thrombosis: The role of factor V Leiden, prothrombin gene mutation and ABO blood groups.

BACKGROUND: Vascular access thrombosis increases morbidity in hemodialysis (HD) patients. The aim of this study was to investigate the association between HD vascular access thrombosis and mutations in the prothrombin and factor V Leiden (FV) genes and ABO blood system. METHODS: This cross-sectional study included 195 patients with end stage renal disease (ESRD) on HD for more than six months. HD patients were allocated into two groups according to the occurrence (cases, N=46) or not (controls, N=149) of previous vascular access thrombosis. FV and prothrombin gene mutations were investigated by polymerase chain reaction and ABO blood group phenotyping was performed by the indirect technique. Univariate analysis detected the variables with a trend to be associated with thrombosis and was followed by multivariate analysis to define independent predictors of vascular access thrombosis. RESULTS: FV Leiden mutation and ABO blood group were not associated with vascular access thrombosis, whereas G20210A mutation in the prothrombin gene was significantly higher in patients with vascular access thrombosis and independently associated with this complication (OR=12.0; CI 95%=1.8-83.5; p=0.012). CONCLUSIONS: G20210A mutation emerges as an important genetic factor predisposing to vascular access thrombosis. The definition of risk factors for thrombosis will certainly enable a rational approach for HD patients.

Comparison of venous plasma glycemia and capillary glycemia for the screening of type 2 diabetes mellitus in the Japanese-Brazilian community of Mombuca (Guatapará-SP).

BACKGROUND: To identify the most appropriate cut-off points of fasting glycemia for the screening of diabetes mellitus type 2 (DM2) with the comparison of the properties of capillary glycemia (CG) and venous blood plasma glycemia (PG) in a population of Japanese origin from the community of Mombuca, Guatapará-SP, Brazil. METHODS: This was a population-based descriptive cross-sectional study conducted on a sample of 131 individuals of both genders aged 20 years or more (66.8% of the target population). CG was measured with a glucometer in a blood sample obtained from the fingertip and PG was determined by an enzymatic method (hexokinase) in venous blood plasma, after a 10-14 hour fast in both cases. Data were analyzed by the receiver operating characteristic (ROC) curve in order to identify the best cut-off point for fasting glycemia (CG and PG) for the diagnosis of DM, using the 2-hour plasma glycemia > 200 mg/dl as gold - standard. RESULTS: The ROC curve revealed that the best cut-off point for the screening of DM was 110 mg/dl for CG and 105 mg/dl for PG, values that would optimize the relation between individuals with positive and false-positive results. The area under the ROC curve was 0.814 for CG (p < 0.01) and 0.836 for PG (p < 0.01). CONCLUSIONS: The cut-off points of 105 mg/dl(5.8 mmol/l) for PG and of 110 mg/dl(6.1 mmol/l) for CG appear to be the most appropriate for the screening of DM2 in the population under study, with emphasis on the fact that the value recommended for CG is 5 mg/dl higher than that for PG, in contrast to WHO recommendations.