Ethnicity and the first diagnosis of a wide range of cardiovascular diseases: Associations in a linked electronic health record cohort of 1 million patients

Background: While the association of ethnic group with individual cardiovascular diseases has been studied, little is known about ethnic differences in the initial lifetime presentation of clinical cardiovascular disease in contemporary populations. Methods and results: We studied 1,068,318 people, aged ≥30 years and free from diagnosed CVD at baseline (90.9% White, 3.6% South Asian and 2.9% Black), using English linked electronic health records covering primary care, hospital admissions, acute coronary syndrome registry and mortality registry (CALIBER research platform). During 5.7 years median follow-up between 1997-2010, 95,224 people experienced an incident cardiovascular diagnosis. 80.2% (77.7% -82.5%) of initial presentation in South Asian <60 yrs were coronary heart disease presentations compared to 66.2% (65.7-66.7) in White and 56.7% (52.1%-61.2%) in Black patients. Compared to White patients, Black patients had significantly lower age-sex adjusted hazard ratios (HRs) for initial lifetime presentation of all the coronary disease diagnoses (stable angina HR 0.80 (95% CI 0.68-0.93); unstable angina – 0.75 (0.59-0.97); myocardial infarction 0.49 (0.40-0.62)) while South Asian patients had significantly higher HRs (stable angina – 1.67 (1.52-1.84); unstable angina 1.82 (1.56-2.13); myocardial infarction – 1.67 (1.49-1.87). We found no ethnic differences in initial presentation with heart failure (Black 0.97 (0.79-1.20); S Asian 1.04(0.87-1.26)). Compared to White patients, Black patients were more likely to present with ischaemic stroke (1.24 (0.97-1.58)) and intracerebral haemorrhage (1.44 (0.97-2.12)). Presentation with peripheral arterial disease was less likely for Black (0.63 (0.50-0.80)) and South Asian patients (0.70 (0.57-0.86)) compared with White patients. Discussion: While we found the anticipated substantial predominance of coronary heart disease presentations in South Asian and predominance of stroke presentations in Black patients, we found no ethnic differences in presentation with heart failure. We consider the public health and research implications of our findings

Bleeding in cardiac patients prescribed antithrombotic drugs: Electronic health record phenotyping algorithms, incidence, trends and prognosis

Background Clinical guidelines and public health authorities lack recommendations on scalable approaches to defining and monitoring the occurrence and severity of bleeding in populations prescribed antithrombotic therapy. Methods We examined linked primary care, hospital admission and death registry electronic health records (CALIBER 1998–2010, England) of patients with newly diagnosed atrial fibrillation, acute myocardial infarction, unstable angina or stable angina with the aim to develop algorithms for bleeding events. Using the developed bleeding phenotypes, Kaplan-Meier plots were used to estimate the incidence of bleeding events and we used Cox regression models to assess the prognosis for all-cause mortality, atherothrombotic events and further bleeding. Results We present electronic health record phenotyping algorithms for bleeding based on bleeding diagnosis in primary or hospital care, symptoms, transfusion, surgical procedures and haemoglobin values. In validation of the phenotype, we estimated a positive predictive value of 0.88 (95% CI 0.64, 0.99) for hospitalised bleeding. Amongst 128,815 patients, 27,259 (21.2%) had at least 1 bleeding event, with 5-year risks of bleeding of 29.1%, 21.9%, 25.3% and 23.4% following diagnoses of atrial fibrillation, acute myocardial infarction, unstable angina and stable angina, respectively. Rates of hospitalised bleeding per 1000 patients more than doubled from 1.02 (95% CI 0.83, 1.22) in January 1998 to 2.68 (95% CI 2.49, 2.88) in December 2009 coinciding with the increased rates of antiplatelet and vitamin K antagonist prescribing. Patients with hospitalised bleeding and primary care bleeding, with or without markers of severity, were at increased risk of all-cause mortality and atherothrombotic events compared to those with no bleeding. For example, the hazard ratio for all-cause mortality was 1.98 (95% CI 1.86, 2.11) for primary care bleeding with markers of severity and 1.99 (95% CI 1.92, 2.05) for hospitalised bleeding without markers of severity, compared to patients with no bleeding. Conclusions Electronic health record bleeding phenotyping algorithms offer a scalable approach to monitoring bleeding in the population. Incidence of bleeding has doubled in incidence since 1998, affects one in four cardiovascular disease patients, and is associated with poor prognosis. Efforts are required to tackle this iatrogenic epidemic

Elastic scattering of electrons by metastable hydrogen atoms in the presence of a resonant laser field

Within the framework of the rotating wave approximation the elastic scattering of electrons by metastable 2s state of hydrogen atoms is studied in the presence of a resonant laser field. The frequency of the circularly polarized laser field is chosen to match the 2s-3p transition frequency in the hydrogen atom. Variation of the cross section with laser intensity $(10^6{-}10^{11} {\rm W cm^{-2}})$ and with incident electron energy (50-150 eV) is investigated

An assessment of thermocline-control methods for packed-bed thermal-energy storage in CSP plants, Part 1: Method descriptions

Thermocline thermal-energy storage (TES) suffers from so-called thermocline degradation, which refers to the flattening of temperature gradients in the TES with successive charging-discharging cycles. Thermocline degradation increases the variations of the heat-transfer fluid (HTF) outflow temperatures, decreases storage utilization factors, and increases specific TES material costs. Methods that prevent or reduce thermocline degradation by changing the operation of the storage are called thermocline-control (TCC) methods. The assessment of TCC methods is the main objective of this work. Three TCC methods that were chosen for this assessment are described in this paper. Two methods, based on either extracting or injecting HTF through ports, were derived from previously published methods while the third method, based on mixing multiple HTF streams, one of which is extracted through a port, is novel. In a companion paper (Geissbühler et al., Solar Energy, submitted 2018), the three TCC methods are assessed for air and molten salt as HTF using simulations of stand-alone storages as well as storages integrated into a concentrated solar power plant.ISSN:0038-092XISSN:1471-125

An assessment of thermocline-control methods for packed-bed thermal-energy storage in CSP plants, Part 2: Assessment strategy and results

Three thermocline-control (TCC) methods are assessed through numerical simulations for a thermal-energy storage (TES) filled with a packed bed of rocks. Two previously suggested methods are based on extracting or injecting heat-transfer fluid (HTF) through ports, while the third is a novel method based on mixing HTF streams. The assessment was carried out using simulations with a model that resolves the packed bed in one dimension. Simulations of stand-alone TES with maximum allowed outflow temperature differences of 10% at quasi-steady conditions showed that the mixing method with three ports led to the largest utilization factors – the fraction of the maximum storage capacity that is actually utilized – of 90.8% and 85.1% for molten salt (MS) and compressed air (CA) as HTF, respectively. These represent relative improvements of 38.8% and 73.4% compared to the baseline configurations without TCC. The increased utilization factors come at the expense of small decreases in the cycle exergy efficiency. For the mixing method with three ports, the exergy efficiencies were 97.3% and 95.6% for MS and CA, respectively. Simulations of a TES with MS as HTF integrated into a CSP plant operating on a Rankine steam cycle showed that TCC increases the annually averaged plant efficiency and the annual net electricity generated solely from thermal energy supplied by the TES. These results suggest that the small decreases in the exergy efficiency of the TES are outweighed by the large increases in the utilization factor.ISSN:0038-092XISSN:1471-125

Consensus dietary guidelines for healthy living and prevention of obesity, the Metabolic syndrome, Diabetes, and related disorders in Asian Indians

India is undergoing rapid nutritional transition, resulting in excess consumption of calories, saturated fats, trans fatty acids, simple sugars, salt and low intake of fiber. Such dietary transition and a sedentary lifestyle have led to an increase in obesity and diet-related non-communicable diseases (type 2 diabetes mellitus [T2DM], cardiovascular disease [CVD], etc.) predominantly in urban, but also in rural areas. In comparison with the previous guidelines, these consensus dietary guidelines include reduction in the intake of carbohydrates, preferential intake of complex carbohydrates and low glycemic index foods, higher intake of fiber, lower intake of saturated fats, optimal ratio of essential fatty acids, reduction in trans fatty acids, slightly higher protein intake, lower intake of salt, and restricted intake of sugar. While these guidelines are applicable to Asian Indians in any geographical setting, they are particularly applicable to those residing in urban and in semi-urban areas. Proper application of these guidelines will help curb the rising "epidemics" of obesity, the metabolic syndrome, hypertension, T2DM, and CVD in Asian Indians