Collaborative meta-analysis of individual participant data from observational studies of Lp-PLA2 and cardiovascular diseases

BACKGROUND

A large number of observational epidemiological studies have reported generally positive associations between circulating mass and activity levels of lipoprotein-associated phospholipase A2 (Lp-PLA2) and the risk of cardiovascular diseases. Few studies have been large enough to provide reliable estimates in different circumstances, such as in different subgroups (e.g., by age group, sex, or smoking status) or at different Lp-PLA2 levels. Moreover, most published studies have related disease risk only to baseline values of Lp-PLA2 markers (which can lead to substantial underestimation of any risk relationships because of within-person variability over time) and have used different approaches to adjustment for possible confounding factors.

OBJECTIVES

By combination of data from individual participants from all relevant observational studies in a systematic 'meta-analysis', with correction for regression dilution (using available data on serial measurements of Lp-PLA2), the Lp-PLA2 Studies Collaboration will aim to characterize more precisely than has previously been possible the strength and shape of the age and sex-specific associations of plasma Lp-PLA2 with coronary heart disease (and, where data are sufficient, with other vascular diseases, such as ischaemic stroke). It will also help to determine to what extent such associations are independent of possible confounding factors and to explore potential sources of heterogeneity among studies, such as those related to assay methods and study design. It is anticipated that the present collaboration will serve as a framework to investigate related questions on Lp-PLA2 and cardiovascular outcomes.

METHODS

A central database is being established containing data on circulating Lp-PLA2 values, sex and other potential confounding factors, age at baseline Lp-PLA2 measurement, age at event or at last follow-up, major vascular morbidity and cause-specific mortality. Information about any repeat measurements of Lp-PLA2 and potential confounding factors has been sought to allow adjustment for possible confounding and correction for regression dilution. The analyses will involve age-specific regression models. Synthesis of the available observational studies of Lp-PLA2 will yield information on a total of about 15 000 cardiovascular disease endpoints.

Overweight and obesity: a remaining problem in women treated for severe gestational diabetes

AIM

To analyse the impact of overweight and obesity on the risk of adverse maternal outcomes and fetal macrosomia in pregnancies of women treated for severe gestational diabetes.

METHODS

This was a population-based cohort study including all singleton pregnancies in Sweden without pre-existing diabetes in the period 1998-2012. Only mothers with an early- pregnancy BMI of ≥ 18.5 kg/m² were included. Logistic regression analysis was used to determine odds ratios with 95% CIs for maternal outcomes and fetal growth. Analyses were stratified by maternal gestational diabetes/non-gestational diabetes to investigate the impact of overweight/obesity in each group.

RESULTS

Of 1 249 908 singleton births, 13 057 were diagnosed with gestational diabetes (1.0%). Overweight/obesity had the same impact on the risks of caesarean section and fetal macrosomia in pregnancies with and without gestational diabetes, but the impact of maternal BMI on the risk of preeclampsia was less pronounced in women with gestational diabetes. Normal-weight women with gestational diabetes had an increased risk of caesarean section [odds ratio 1.26 (95% CI 1.16-1.37)], preeclampsia [odds ratio 2.03 (95% CI 1.71-2.41)] and large-for-gestational-age infants [odds ratio 2.25 (95% CI 2.06-2.46)]. Risks were similar in the overweight group without gestational diabetes, caesarean section [odds ratio 1.34 (1.33-1.36)], preeclampsia odds ratio [1.76 (95% CI 1.72-1.81)], large-for-gestational-age [odds ratio 1.76 (95% CI 1.74-1.79)].

CONCLUSIONS

Maternal overweight and obesity is associated with similar increments in risks of adverse maternal outcomes and delivery of large-for-gestational-age infants in women with and without gestational diabetes. Obese women with gestational diabetes are defined as a high-risk group. Normal-weight women with gestational diabetes have similar risks of adverse outcomes to overweight women without gestational diabetes.

Optimal consumption with stochastic prices in continuous time

In this paper we consider an economic agent (the consumer) having initial wealth x(0), which he is allowed to spend during the time interval [0, T]. There are N consumer goods, the prices of which are described by a system of stochastic differential equations, and the consumer can spend his money as he pleases provided that he does not get into debt. The consumer's problem is to maximize his expected utility over [0, T]. Given a separable utility function we show that the optimal consumption policy is linear in the wealth variable regardless of the structure of the price system, and if we assume that the price processes are geometric Brownian motions we can give the optimal consumption policy explicitly.

Abstract P5-01-04: uPAR PET imaging in breast cancer: First-in-humans studies using 64Cu-DOTA-AE105 and 68Ga-NOTA-AE105

Objective

The urokinase-type plasminogen activator receptor (uPAR) is a well-established prognostic biomarker in many cancer types including breast cancer (BC). Numerous studies using immunohistochemically evaluation of uPAR expression in tissue samples from BC patients have shown that not only is uPAR consistently overexpressed, but also carries strong prognostic value and is associates with overall survival. Accordingly, uPAR is an obvious target for identifying BC and for phenotyping aggressiveness in BC. Using whole body Positron Emission Tomography (PET) imaging rather than tissue specimens circumvents possible sampling error and allows for staging. Our objective was therefore to perform first-in-humans studies of uPAR-specific PET imaging in BC using either 64Cu-DOTA-AE105 or 68Ga-NOTA-AE105

Methods

Six patients with BC and scheduled for surgery were included. Prior to operation, patients were either PET/CT scanned 1, 3 and 24 h after injection of the uPAR PET ligand 64Cu-DOTA-AE105 (n=3; half life of 64Cu: 13 h) or PET/CT scanned 10 min, 1 h or 2 h after injection of 68Ga-NOTA-AE105 (n=3; half life of 68Ga: 1 h). PET Images were visually analyzed for visible tumor uptake of 64Cu-DOTA-AE105 or 68Ga-NOTA-AE105 and Standardized Uptake Values (SUV) were obtained by manually drawing volumes of interest (VOIs) around the primary tumor as well as identified metastases. Results are given as SUVmax. Tumor-to-background ratios relative to liver, kidney, blood and muscle were also calculated. Surgical tumor specimens were obtained from all patients during subsequent surgery. In addition to routine pathological examination, tissue was analyzed for ex vivo uPAR expression as target validation.

Results

Both primary tumors and metastases were visually detectable. For 64Cu-DOTA-AE105 SUVmax values were 2.9–4.0., and 2.9-4.0 after 1 and 3 h, respectively. Tumor-to-background ratios after 1 h were 0.91 (tumor-liver), 1.65 (tumor-kidney), 0.96 (tumor-blood) and 8.9 (tumor-muscle), respectively. Tumor-to-background ratios after 3 h were 0.50 (tumor-liver), 0.96 (tumor-kidney), 4.2 (tumor-blood) and 11.4 (tumor-muscle), respectively. Ex vivo analysis by immunohistochemistry confirmed uPAR expression in all primary cancer lesions. For 68Ga-NOTA-AE105, SUVmax was 5.0, 3.8 and 4.2 after 10 min, 1 h and 3 h, respectively (first patient analyzed). Tumor-to-background ratios after 10 min were 2.8 (tumor-liver), 0.4 (tumor-kidney), 1.6 (tumor-blood) and 8.4 (tumor-muscle), respectively. Tumor-to-background ratios after 1 h were 3.2 (tumor-liver), 0.6 (tumor-kidney), 1.7 (tumor-blood) and 7.1 (tumor-muscle), respectively.

Conclusion

This is the first study in humans using PET imaging of uPAR in BC. Both primary tumors and metastases were clearly visible with robust PET tracer uptake and a high and sufficient contrast between tumors and background. Our data supports continuation into phase II clinical studies using uPAR PET for staging and risk stratification, which potentially may be used for selection of treatment strategy in BC.

Citation Format: Kjaer A, Persson M, Skovgaard D, Brandt-Larsen M, Christensen C, Madsen J, Nielsen CH, Loft A, Berthelsen AK, Kroman N, Højgaard L. uPAR PET imaging in breast cancer: First-in-humans studies using 64Cu-DOTA-AE105 and 68Ga-NOTA-AE105. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-01-04.

Using Hansen solubility parameters to predict the dispersion of nano-particles in polymeric films

A new surface modification followed by calculation of Hansen solubility parameters to predict dispersability of cellulose nanocrystals in LDPE is presented.

The Swedish CArdioPulmonary BioImage Study: objectives and design

Cardiopulmonary diseases are major causes of death worldwide, but currently recommended strategies for diagnosis and prevention may be outdated because of recent changes in risk factor patterns. The Swedish CArdioPulmonarybioImage Study (SCAPIS) combines the use of new imaging technologies, advances in large-scale 'omics' and epidemiological analyses to extensively characterize a Swedish cohort of 30 000 men and women aged between 50 and 64 years. The information obtained will be used to improve risk prediction of cardiopulmonary diseases and optimize the ability to study disease mechanisms. A comprehensive pilot study in 1111 individuals, which was completed in 2012, demonstrated the feasibility and financial and ethical consequences of SCAPIS. Recruitment to the national, multicentre study has recently started.

Functional outcomes in the Cleft Care UK study--Part 3: oral health and audiology

OBJECTIVES

To compare oral health and hearing outcomes from the Clinical Standards Advisory Group (CSAG, 1998) and the Cleft Care UK (CCUK, 2013) studies.

SETTING AND SAMPLE POPULATION

Two UK-based cross-sectional studies of 5-year-olds born with non-syndromic unilateral cleft lip and palate undertaken 15 years apart. CSAG children were treated in a dispersed model of care with low-volume operators. CCUK children were treated in a centralized, high volume operator system.

MATERIALS AND METHODS

Oral health data were collected using a standardized proforma. Hearing was assessed using pure tone audiometry and middle ear status by otoscopy and tympanometry. ENT and hearing history were collected from medical notes and parental report.

RESULTS

Oral health was assessed in 264 of 268 children (98.5%). The mean dmft was 2.3, 48% were caries free, and 44.7% had untreated caries. There was no evidence this had changed since the CSAG survey. Oral hygiene was generally good, 96% were enrolled with a dentist. Audiology was assessed in 227 of 268 children (84.7%). Forty-three per cent of children received at least one set of grommets--a 17.6% reduction compared to CSAG. Abnormal middle ear status was apparent in 50.7% of children. There was no change in hearing levels, but more children with hearing loss were managed with hearing aids.

CONCLUSIONS

Outcomes for dental caries and hearing were no better in CCUK than in CSAG, although there was reduced use of grommets and increased use of hearing aids. The service specifications and recommendations should be scrutinized and implemented.

Residual organic matter and microbial respiration in bottom ash: Effects on metal leaching and eco-toxicity

A common assumption regarding the residual organic matter, in bottom ash, is that it does not represent a significant pool of organic carbon and, beyond metal-ion complexation process, it is of little consequence to evolution of ash/leachate chemistry. This article evaluates the effect of residual organic matter and associated microbial respiratory processes on leaching of toxic metals (i.e. arsenic, copper, chromium, molybdenum, nickel, lead, antimony and zinc), eco-toxicity of ash leachates. Microbial respiration was quantified with help of a respirometric test equipment OXITOP control system. The effect of microbial respiration on metal/residual organic matter leaching and eco-toxicity was quantified with the help of batch leaching tests and an eco-toxicity assay - Daphnia magna. In general, the microbial respiration process decreased the leachate pH and eco-toxicity, indicating modification of bioavailability of metal species. Furthermore, the leaching of critical metals, such as copper and chromium, decreased after the respiration in both ash types (fresh and weathered). It was concluded that microbial respiration, if harnessed properly, could enhance the stability of fresh bottom ash and may promote its reuse.

Measures of atherosclerotic burden are associated with clinically manifest cardiovascular disease in type 2 diabetes: a European cross-sectional study

BACKGROUND

There is a need to develop and validate surrogate markers of cardiovascular disease (CVD) in subjects with diabetes. The macrovascular changes associated with diabetes include aggravated atherosclerosis, increased arterial stiffness and endothelial dysfunction. The aim of this study was to determine which of these factors is most strongly associated with clinically manifest cardiovascular events.

METHODS

Vascular changes were measured in a cohort of 458 subjects with type 2 diabetes (T2D) and CVD (myocardial infarction, stroke or lower extremity arterial disease), 527 subjects with T2D but without clinically manifest CVD and 515 subjects without T2D and with or without CVD.

RESULTS

Carotid intima-media thickness (IMT) and ankle-brachial pressure index were independently associated with the presence of CVD in subjects with T2D, whereas pulse wave velocity and endothelial function provided limited independent additive information. Measurement of IMT in the carotid bulb provided better discrimination of the presence of CVD in subjects with T2D than measurement of IMT in the common carotid artery. The factors most significantly associated with increased carotid IMT in T2D were age, disease duration, systolic blood pressure, impaired renal function and increased arterial stiffness, whereas there were no or weak independent associations with metabolic factors and endothelial dysfunction.

CONCLUSIONS

Measures of atherosclerotic burden are associated with clinically manifest CVD in subjects with T2D. In addition, vascular changes that are not directly related to known metabolic risk factors are important in the development of both atherosclerosis and CVD in T2D. A better understanding of the mechanisms involved is crucial for enabling better identification of CVD risk in T2D.

Toggling the Local Electric Field with an Embedded Adatom Switch

By means of scanning probe microscopy we demonstrate that Au(+) on NaCl films adsorbs in an embedded, slightly off-centered Cl-Cl bridge position and can be switched between two equivalent mirror-symmetric configurations using the attractive force exerted by a scanning probe tip. Density functional theory calculations demonstrate that the displacement of the Au atom from the centered position of the bridge configuration is accompanied by a large lifting of the closest Cl atom leading to significant changes in the local electrostatic field. Our findings suggest that Au(+) can be used to toggle the local electrostatic field.

Manipulation of the charge state of single Au atoms on insulating multilayer films

We show charge-state manipulation of single Au adatoms on 2-11 monolayer (ML) thick NaCl films on Cu surfaces by attaching or detaching single electrons via the tip of an atomic force microscope (AFM). Tristate charge control (neutral, negatively charged, and positively charged) is achieved. On Cu(100) and Cu(111) supports, charge tristability is achieved independently of the NaCl layer thickness. In contrast, on Cu(311), only Au anions are stable on the thinnest NaCl films, but neutral and positive charge states become sufficiently long lived on films thicker than 4 ML to allow AFM-based charge-state-manipulation experiments.

Perinatal outcome in relation to fetal sex in offspring to mothers with pre-gestational and gestational diabetes--a population-based study

AIM

The objective of the present study was to investigate if perinatal outcome differs with fetal sex in pregnancies with maternal Type 1 diabetes, Type 2 diabetes or gestational diabetes.

METHODS

This was a population-based cohort study, with data from the Medical Birth Registry in Sweden throughout the period 1998-2007. Singleton pregnancies with maternal Type 1 diabetes (n = 4092), Type 2 diabetes (n = 412) and gestational diabetes (n = 8602) were identified based on the International Classification of Diseases, 10th edition code. For comparison, 905 565 pregnancies without diabetes were included. The primary outcome was a composite outcome, consisting of any of the following diagnoses: perinatal mortality rate, major malformation, preterm delivery, acute respiratory disorders and neonatal hypoglycaemia. Logistic regression was used to obtain odds ratios for adverse outcomes in male offspring within the diabetic and reference cohorts, respectively.

RESULTS

In pregnancies with diabetes, maternal characteristics did not differ with fetal sex, except for a higher rate of Caesarean delivery in male offspring of women with Type 1 diabetes. Male infants to mothers with Type 1 diabetes and gestational diabetes had significantly increased odds of respiratory disorders [adjusted odds ratio (confidence interval) Type 1 diabetes: 1.50 (1.12-2.02); gestational diabetes: 1.81 (1.27-2.57)]. Male infants to mothers with gestational diabetes also had significantly increased odds of major malformations [adjusted odds ratio: 1.44 (1.07-1.93)]. In offspring of mothers with Type 2 diabetes, odds ratios of most outcomes were higher in male infants; however, not significantly different from female infants. In pregnancies without diabetes, male infants had significantly higher odds of all adverse outcomes, except perinatal mortality rate.

CONCLUSION

The risk of adverse perinatal outcome in offspring of mothers with Type 1 diabetes and gestational diabetes did not differ by sex, except for a higher risk in male infants for respiratory disorders. The risk of major malformations was also significantly increased in male offspring to mothers with gestational diabetes. In offspring of mothers with Type 2 diabetes, no significant differences between sexes were found.

Glucagon dynamics during hypoglycaemia and food-re-challenge following treatment with vildagliptin in insulin-treated patients with type 2 diabetes

AIMS

To determine the effects of dipeptidyl peptidase-4 (DPP-4) inhibition on glucagon dynamics in patients with insulin-treated type 2 diabetes (T2D).

METHODS

The study was a single-centre, double-blind, randomized, placebo controlled crossover study in patients with T2D, mean age 59 ± 6 (s.d.) years and mean haemoglobin A1c 7.7 ± 0.8%, treated with exogenous insulin with or without oral antihyperglycaemic agents. Patients received vildagliptin (50 mg BID) or placebo as add-on to insulin for 4 weeks in random order with a 4-week washout in-between. On day 28 of the respective treatment, patients were served a standard meal (500 kcal) followed by a hyperinsulinaemic hypoglycaemic clamp (target 2.5 mmol/l) and a subsequent food re-challenge (700 kcal). The completers population (n = 29) was analysed.

RESULTS

Glucose levels were lower with vildagliptin than with placebo during the meal [areas under the curve (AUC) 1.23 ± 0.07 vs. 1.46 ± 0.05 mol/l min, P < 0.001] and similar between the groups during the clamp. During the meal, glucagon levels were lower with vildagliptin (AUC 1.98 ± 0.15 vs. 2.15 ± 0.17 nmol/l min, P = 0.016). In contrast, the glucagon counter-regulation to the insulin-induced hypoglycaemia was sustained by vildagliptin (6.05 ± 1.20 pmol/l during vildagliptin vs.6.94 ± 1.09 pmol/l during placebo, NS). During the food re-challenge after hypoglycaemia, glucagon levels were, again, significantly lower after vildagliptin (AUC 1.30 ± 0.11 vs. 1.52 ± 0.12 nmol/l min, P < 0.039). Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) levels were significantly elevated by vildagliptin compared to placebo during meal, hypoglycaemia and food re-challenge.

CONCLUSIONS

Vildagliptin action to block GLP-1 and GIP inactivation by DPP-4 improves glucagon dynamics during hypoglycaemia, hyperglycaemia and food re-challenge.

Red cell distribution width, haemoglobin A1c and incidence of diabetes mellitus

OBJECTIVE

Hyperglycaemia has multiple effects on the red blood cell (RBC), including glycation of haemoglobin, reduced deformability and reduced lifespan. Red cell distribution width (RDW) is a measure of the heterogeneity of erythrocyte volumes. The aim of this study was to explore the relationships between RDW and glucose, haemoglobin A1c (HbA1c) and incidence of diabetes mellitus (DM).

DESIGN, SETTING AND SUBJECTS

RDW and mean corpuscular volume were measured in 26 709 non-diabetic participants (aged 45-73 years) from the population-based Malmö Diet and Cancer cohort. HbA1c and fasting venous blood glucose levels were measured in 4845 subjects.

MAIN OUTCOME MEASURE

Incidence of DM (n = 2944) over 14 years of follow-up was studied by linkage with national and local DM registers.

RESULTS

Individuals with low RDW had significantly higher risk of developing DM [adjusted hazard ratio (HR) 1.48, 95% confidence interval (CI) 1.29-1.70, for 1st vs. 4th quartile], especially in subjects with impaired fasting glucose (n = 416) (HR 2.15, 95% CI 1.12-4.14). Low RDW was also associated with significantly higher waist circumference and glucose, insulin and triglyceride concentrations. By contrast, RDW was significantly and positively associated with HbA1c, corresponding an increase in HbA1c of 0.10% per 1 SD increase in RDW.

CONCLUSION

Low RDW is associated with increased incidence of DM independently of other risk factors. We propose that low RDW could be a surrogate marker of reduced RBC survival, with lower HbA1c due to shorter duration of glucose exposure. RDW is a biomarker that could improve risk assessment for individuals at risk of developing DM.

Cystatin C identifies cardiovascular risk better than creatinine-based estimates of glomerular filtration in middle-aged individuals without a history of cardiovascular disease

OBJECTIVES

Creatinine- and cystatin C-based estimates of renal function are considered to be cardiovascular disease (CVD) risk factors, but the clinical utility in middle-aged subjects without a history of CVD is controversial.

DESIGN

We related plasma cystatin C and creatinine-based glomerular filtration rate (GFR) [MDRD, CKD-EPI-2009, and CKD-EPI-comb (a combination of creatinine and cystatin C)] to incident CVD, CVD mortality, all-cause mortality, and heart failure in 4650 middle-aged subjects without CVD.

RESULTS

The hazard ratio (HR) per standard deviation increment (95% CI) of cystatin C predicted incident CVD (1.22, 1.11-1.33; P < 0.0001), CVD mortality (1.44, 1.24-1.66; P < 0.0001), all-cause mortality (1.15, 1.05-1.26; P = 0.002), and heart failure (1.27, 1.05-1.55; P = 0.02), whereas MDRD and CKD-EPI-2009 only predicted CVD mortality (0.79, 0.66-0.93; P = 0.006 and 0.78, 0.66-0.92; P = 0.003, respectively). Cystatin C led to a significant increase in the net reclassification improvement for all endpoints, except heart failure. Only within the quartile with the worst renal function were all measures related to all-cause and CVD mortality. The top 25% of cystatin C in the population significantly predicted risk of incident CVD and CVD mortality, whereas MDRD and CKD-EPI-2009 were predictors of CVD mortality only at a GFR < 60 mL/min/1.73 m(2) (11-13% of the population) and of incident CVD only at a GFR < 45 mL/min/1.73 m(2) (<1% of the population).

CONCLUSION

Cystatin C is a better risk marker for CVD morbidity and mortality than creatinine-based GFR. Whether this is explained by cystatin C being a better marker for true GFR or through other effects of cystatin C remains to be shown.