Investigation of the in vivo estrogenicity of the UV-filters 4-methylbenzylidene camphor and octyl methoxy cinnamate in rainbow trout (Oncorhynchus mykiss)

The estrogenic activity of the chemical UV-filters, 4-methylbenzylidene camphor (4-MBC) and octyl methoxy cinnamate (OMC) was investigated in an in vivo rainbow trout (Oncorhynchus mykiss) assay. Plasma vitellogenin concentrations were quantified by means of an Enzyme Linked Immuno Sorbent Assay (ELISA) in juvenile rainbow trout before and after intraperitoneal injection of the test compounds. Injection of 4-MBC on day 0, 3, 6 and 10 in the exposure period caused dose and time dependent increases in the concentration of plasma vitellogenin. Significant elevation of vitellogenin concentrations in plasma was demonstrated from 151 mg 4-MBC kg-1 injection-1. Logistic regression analysis relating the percentage of responding fish to the injected dose of 4-MBC resulted in ED10, ED50 and ED90 values of 37, 115 and 194 mg kg-1 injection-1, respectively, after 14 days of exposure (4 injections). Injections with OMC (up to 202 mg kg-1 injection-1) did not result in a statistically significant response in groups of exposed fish, although some individual fish showed elevated concentrations of vitellogenin in plasma. The results confirm that 4-MBC is estrogenic in fish in vivo.

Baseline findings of the population-based, randomized, multifaceted Danish cardiovascular screening trial (DANCAVAS) of men aged 65–74 years

Background

The challenge of managing age-related diseases is increasing; routine checks by the general practitioner do not reduce cardiovascular mortality. The aim here was to reduce cardiovascular mortality by advanced population-based cardiovascular screening. The present article reports the organization of the study, the acceptability of the screening offer, and the relevance of multifaceted screening for prevention and management of cardiovascular disease.

Methods

Danish men aged 65–74 years were invited randomly (1 : 2) to a cardiovascular screening examination using low-dose non-contrast CT, ankle and brachial BP measurements, and blood tests.

Results

In all, 16 768 of 47 322 men aged 65–74 years were invited and 10 471 attended (uptake 62·4 per cent). Of these, 3481 (33·2 per cent) had a coronary artery calcium score above 400 units. Thoracic aortic aneurysm was diagnosed in the ascending aorta (diameter 45 mm or greater) in 468 men (4·5 per cent), in the arch (at least 40 mm) in 48 (0·5 per cent) and in the descending aorta (35 mm or more) in 233 (2·2 per cent). Abdominal aortic aneurysm (at least 30 mm) and iliac aneurysm (20 mm or greater) were diagnosed in 533 (5·1 per cent) and 239 (2·3 per cent) men respectively. Peripheral artery disease was diagnosed in 1147 men (11·0 per cent), potentially uncontrolled hypertension (at least 160/100 mmHg) in 835 (8·0 per cent), previously unknown atrial fibrillation confirmed by ECG in 50 (0·5 per cent), previously unknown diabetes mellitus in 180 (1·7 per cent) and isolated severe hyperlipidaemia in 48 men (0·5 per cent).

In all, 4387 men (41·9 per cent), excluding those with potentially uncontrolled hypertension, were referred for additional cardiovascular prevention. Of these, 3712 (35·5 per cent of all screened men, but 84·6 per cent of those referred) consented and were started on medication.

Conclusion

Multifaceted cardiovascular screening is feasible and may optimize cardiovascular disease prevention in men aged 65–74 years. Uptake is lower than in aortic aneurysm screening.

Cost-effectiveness of population-based vascular disease screening and intervention in men from the Viborg Vascular (VIVA) trial

Background

Population-based screening and intervention for abdominal aortic aneurysm, peripheral artery disease and hypertension was recently reported to reduce the relative risk of mortality among Danish men by 7 per cent. The aim of this study was to investigate the cost-effectiveness of vascular screening versus usual care (ad hoc primary care-based risk assessment) from a national health service perspective.

Methods

A cost-effectiveness evaluation was conducted alongside an RCT involving all men from a region in Denmark (50 156) who were allocated to screening (25 078) or no screening (25 078) and followed for up to 5 years. Mobile nurse teams provided screening locally and, for individuals with positive test results, referrals were made to general practices or hospital-based specialized centres for vascular surgery. Intention-to-treat-based, censoring-adjusted incremental costs (2014 euros), life-years and quality-adjusted life-years (QALYs) were estimated using Lin's average estimator method. Incremental net benefit was estimated using Willan's estimator and sensitivity analyses were conducted.

Results

The cost of screening was estimated at €148 (95 per cent c.i. 126 to 169), and the effectiveness at 0·022 (95 per cent c.i. 0·006 to 0·038) life-years and 0·069 (0·054 to 0·083) QALYs, generating average costs of €6872 per life-year and €2148 per QALY. At a willingness-to-pay threshold of €40 000 per QALY, the probabilities of cost-effectiveness were 98 and 99 per cent respectively. The probability of cost-effectiveness was 71 per cent when all the sensitivity analyses were combined into one conservative scenario.

Conclusion

Vascular screening appears to be cost-effective and compares favourably with current screening programmes.

The DanCavas Pilot Study of Multifaceted Screening for Subclinical Cardiovascular Disease in Men and Women Aged 65-74 Years

OBJECTIVE/BACKGROUND

This pilot study of a large population based randomised screening trial investigated feasibility, acceptability, and relevance (prevalence of clinical and subclinical cardiovascular disease [CVD] and proportion receiving insufficient prevention) of a multifaceted screening for CVD.

METHODS

In total, 2060 randomly selected Danish men and women aged 65-74 years were offered (i) low dose non-contrast computed tomography to detect coronary artery calcification (CAC) and aortic/iliac aneurysms; (ii) detection of atrial fibrillation (AF); (iii) brachial and ankle blood pressure measurements; and (iv) blood levels of cholesterol and hemoglobin A1c. Web based self booking and data management was used to reduce the administrative burden.

RESULTS

Attendance rates were 64.9% (n = 678) and 63.0% (n = 640) for men and women, respectively. In total, 39.7% received a recommendation for medical preventive actions. Prevalence of aneurysms was 12.4% (95% confidence interval [CI] 9.9-14.9) in men and 1.1% (95% CI 0.3-1.9) in women, respectively (p < .001). A CAC score > 400 was found in 37.8% of men and 11.3% of women (p < .001), along with a significant increase in median CAC score with age (p = .03). Peripheral arterial disease was more prevalent in men (18.8%, 95% CI 15.8-21.8) than in women (11.2%, 95% CI 8.7-13.6). No significant differences between the sexes were found with regard to newly discovered AF (men 1.3%, women 0.5%), potential hypertension (men 9.7%, women 11.5%), hypercholesterolemia (men 0.9%, women 1.1%) or diabetes mellitus (men 2.1%, women 1.3%).

CONCLUSION

Owing to the higher prevalence of severe conditions, such as aneurysms and CAC ≥ 400, screening for CVD seemed more prudent in men than women. The attendance rates were acceptable compared with other screening programs and the logistical structure of the screening program proved successful.

Exercise-based cardiac rehabilitation after heart valve surgery: cost analysis of healthcare use and sick leave

Background

Owing to a lack of evidence, patients undergoing heart valve surgery have been offered exercise-based cardiac rehabilitation (CR) since 2009 based on recommendations for patients with ischaemic heart disease in Denmark. The aim of this study was to investigate the impact of CR on the costs of healthcare use and sick leave among heart valve surgery patients over 12 months post surgery.

Methods

We conducted a nationwide survey on the CR participation of all patients having undergone valve surgery between 1 January 2011 and 30 June 2011 (n=667). Among the responders (n=500, 75%), the resource use categories of primary and secondary healthcare, prescription medication and sick leave were analysed for CR participants (n=277) and non-participants (n=223) over 12 months. A difference-in-difference analysis was undertaken. All estimates were presented as the means per patient (95% CI) based on non-parametric bootstrapping of SEs.

Results

Total costs during the 12 months following surgery were €16 065 per patient (95% CI 13 730 to 18 399) in the CR group and €15 182 (12 695 to 17 670) in the non-CR group. CR led to 5.6 (2.9 to 8.3, p<0.01) more outpatient visits per patient. No statistically significant differences in other cost categories or total costs €1330 (−4427 to 7086, p=0.65) were found between the groups.

Conclusions

CR, as provided in Denmark, can be considered cost neutral. CR is associated with more outpatient visits, but CR participation potentially offsets more expensive outpatient visits. Further studies should investigate the benefits of CR to heart valve surgery patients as part of a formal cost-utility analysis.

Baseline prevalence of abdominal aortic aneurysm, peripheral arterial disease and hypertension in men aged 65–74 years from a population screening study (VIVA trial)

Background

Abdominal aortic aneurysm (AAA) screening has been introduced into some health systems and could easily be supplemented with broader vascular screening. The aim of this study was to evaluate the screening set-up and investigate combined screening for AAA, peripheral arterial disease (PAD) and possible hypertension (HT), and detection rates.

Methods

This observational study was based on the intervention arm of a screening trial in 25 083 Danish men aged 65–74 years. A combined screening programme for AAA, PAD and HT was offered at local hospitals. Participants with positive test results were offered secondary prophylaxis and/or referred to their general practitioner. The programme set-up included decentralized screening by three mobile teams at 14 venues. Diagnostic criteria were: aortic diameter at least 30 mm for AAA, ankle : brachial pressure index below 0·9 or above 1·4 for PAD, and BP exceeding 160/100 mmHg for HT.

Results

Overall, 18 749 men (uptake 74·7 per cent) attended the screening. An AAA was diagnosed in 3·3 (95 per cent c.i. 3·0 to 3·6) per cent, PAD in 10·9 (10·5 to 11·4) per cent and HT in 10·5 (10·0 to 10·9) per cent. Lipid-lowering and/or antiplatelet treatment was initiated in 34·8 per cent of the participants.

Conclusion

Preventive actions were started in one-third of the attenders. The long-term effect of this on morbidity and mortality is an important part of future analysis. The trial confirms that the prevalence of AAA in Denmark has decreased only slightly in the past decade, from 4·0 to 3·3 per cent, in contrast to other nations.

A three-year follow-up on the efficacy of psychosocial interventions for patients with mild dementia and their caregivers: the multicentre, rater-blinded, randomised Danish Alzheimer Intervention Study (DAISY)

OBJECTIVES

To examine the long-term efficacy at the 36-month follow-up of an early psychosocial counselling and support programme lasting 8-12 months for community-dwelling patients with mild Alzheimer's disease and their caregivers.

DESIGN

Multicentre, randomised, controlled, rater-blinded trial.

SETTING

Primary care and memory clinics in five Danish districts.

PARTICIPANTS

330 home-dwelling patients with mild Alzheimer's disease and their primary caregivers (dyads).

INTERVENTIONS

Dyads were randomised to receive intervention during the first year after diagnosis. Both intervention and control groups had follow-up visits at 3, 6, 12 and 36 months.

MAIN OUTCOME MEASURES

Primary outcomes for the patients assessed at 36-month follow-up were changes from baseline in global cognitive function (Mini-Mental State Examination), depressive symptoms (Cornell Depression Scale) and proxy-rated EuroQoL quality of life on visual analogue scale. The primary outcomes for the caregivers were changes from baseline in depressive symptoms (Geriatric Depression Scale) and self-rated EuroQoL quality of life on a visual analogue scale. The secondary outcome measures for the patient were proxy-rated Quality of Life Scale for Alzheimer's disease (QoL-AD), Neuropsychiatric Inventory-Questionnaire, Alzheimer's disease Cooperative Study Activities of Daily Living Scale, all-cause mortality and nursing home placement.

RESULTS

At a 36-month follow-up, 2 years after the completion of the Danish Alzheimer Intervention Study (DAISY), the unadjusted positive effects previously detected at the 12-month follow-up in one patient primary outcome (Cornell depression score) and one patient secondary outcome (proxy-rated QoL-AD) disappeared (Cornell depression score, p=0.93; proxy-rated QoL-AD, p=0.81). No long-term effect of DAISY intervention on any other primary and secondary outcomes was found at the 36-month follow-up.

CONCLUSIONS

For patients with very mild Alzheimer's disease and their caregivers, an intensive, multi-component, semitailored psychosocial intervention programme with counselling, education and support during the first year after diagnosis did not show any positive long-term effect on primary and secondary outcomes.

TRIAL REGISTRATION

The study was registered in the Clinical Trial Database (http://www.controlled-trials.com/ISRCTN74848736).

Long-term benefit and cost-effectiveness analysis of screening for abdominal aortic aneurysms from a randomized controlled trial

Background

The aim was to estimate long-term mortality benefits and cost-effectiveness of screening for abdominal aortic aneurysm (AAA) in men aged 64–73 years.

Methods

All men aged 64–73 years living in Viborg County were randomized to be controls (n = 6306) or invited for abdominal ultrasonography at a regional hospital (n = 6333). Mortality and AAA-related interventions were recorded in national databases. The cost of initial screening was based on actual costs of the programme. Incremental cost-effectiveness ratios (ICERs) were calculated on gains in life years and Quality Adjusted Life Years (QALY). Discounting (3 per cent) was applied to both costs and effects, and all costs were adjusted to euros at 2007 prices.

Results

The relative risk reduction of the screening programme in AAA-related mortality was 66 per cent (hazard ratio 0·34, 95 per cent confidence interval (c.i.) 0·20 to 0·57). The corresponding risk reduction in all-cause mortality was 2 per cent (hazard ratio 0·98, 95 per cent c.i. 0·93 to 1·03). The ICER was estimated at €157 (−3292 to 4401) per life year gained and €179 (−4083 to 4682) per QALY gained. Screening was found to be cost effective at a probability above 0·97 for a willingness-to-pay threshold of only €5000. One-way sensitivity analysis demonstrated that this result was robust to various alternative assumptions, as the probability did not drop below 0·90 for any scenario.

Conclusion

The mortality benefit of screening for AAA in men aged 64–73 years was maintained in the longer term and screening was cost effective. Registration number: ISRCTN65822028 (http://www.controlled-trials.com).

Capsaicin regulates voltage-dependent sodium channels by altering lipid bilayer elasticity

At submicromolar concentrations, capsaicin specifically activates the TRPV1 receptor involved in nociception. At micro- to millimolar concentrations, commonly used in clinical and in vitro studies, capsaicin also modulates the function of a large number of seemingly unrelated membrane proteins, many of which are similarly modulated by the capsaicin antagonist capsazepine. The mechanism(s) underlying this widespread regulation of protein function are not understood. We investigated whether capsaicin could regulate membrane protein function by changing the elasticity of the host lipid bilayer. This was done by studying capsaicin's effects on lipid bilayer stiffness, measured using gramicidin A (gA) channels as molecular force-transducers, and on voltage-dependent sodium channels (VDSC) known to be regulated by bilayer elasticity. Capsaicin and capsazepine (10-100 microM) increase gA channel appearance rate and lifetime without measurably altering bilayer thickness or channel conductance, meaning that the changes in bilayer elasticity are sufficient to alter the conformation of an embedded protein. Capsaicin and capsazepine promote VDSC inactivation, similar to other amphiphiles that decrease bilayer stiffness, producing use-dependent current inhibition. For capsaicin, the quantitative relation between the decrease in bilayer stiffness and the hyperpolarizing shift in inactivation conforms to that previously found for other amphiphiles. Capsaicin's effects on gA channels and VDSC are similar to those of Triton X-100, although these amphiphiles promote opposite lipid monolayer curvature. We conclude that capsaicin can regulate VDSC function by altering bilayer elasticity. This mechanism may underlie the promiscuous regulation of membrane protein function by capsaicin and capsazepine-and by amphiphilic drugs generally.

KCNQ4 channels expressed in mammalian cells: functional characteristics and pharmacology

Human cloned KCNQ4 channels were stably expressed in HEK-293 cells and characterized with respect to function and pharmacology. Patch-clamp measurements showed that the KCNQ4 channels conducted slowly activating currents at potentials more positive than -60 mV. From the Boltzmann function fitted to the activation curve, a half-activation potential of -32 mV and an equivalent gating charge of 1.4 elementary charges was determined. The instantaneous current-voltage relationship revealed strong inward rectification. The KCNQ4 channels were blocked in a voltage-independent manner by the memory-enhancing M current blockers XE-991 and linopirdine with IC(50) values of 5.5 and 14 microM, respectively. The antiarrhythmic KCNQ1 channel blocker bepridil inhibited KCNQ4 with an IC(50) value of 9.4 microM, whereas clofilium was without significant effect at 100 microM. The KCNQ4-expressing cells exhibited average resting membrane potentials of -56 mV in contrast to -12 mV recorded in the nontransfected cells. In conclusion, the activation and pharmacology of KCNQ4 channels resemble those of M currents, and it is likely that the function of the KCNQ4 channel is to regulate the subthreshold electrical activity of excitable cells.