BMI and all-cause mortality in older adults: a meta-analysis

Whether the association between body mass index (BMI) and all-cause mortality for older adults is the same as for younger adults is unclear.

Optimal second best taxation of addictive goods in dynamic general equilibrium: a revenue raising perspective

In this paper we derive conditions under which optimal tax rates for addictive goods exceed tax rates for non-addictive consumption goods within a rational addiction framework where exogenous government spending cannot be financed with lump sum taxes. We reexamine classic results on optimal commodity taxation and find a rich set of new findings. Two dynamic effects exist. First, households anticipating higher future addictive tax rates reduce current addictive consumption, so they will be less addicted when the tax rate increases. Therefore, addictive tax revenue falls prior to the tax increase. Surprisingly, the optimal tax rate on addictive goods is generally decreasing in the strength of tolerance, since strong tolerance strengthens this tax anticipation effect. Second, high current tax rates on addictive goods make households less addicted in the future, affecting all future tax revenues in a way which depends on how elasticities are changing over time. Classic results on uniform commodity taxation emerge as special cases when elasticities are constant and the addiction function is homogeneous of degree one. Finally, we also study features of addictive goods such as complementarity to leisure that, while not directly related to the definition of addiction, are nonetheless properties many addictive goods display.

General approach for electrochemical functionalization of glassy carbon surface by in situ generation of diazonium ion under acidic and non-acidic condition with a cascade protocol

Immobilization of catechol derivatives on GC electrode surfaces can be performed by in situ generation and reduction of nitrocatechol. We present the oxidative nitration of catechol in the presence of nitrous acid followed by electrochemically reduction of the generated nitro aromatic group to the corresponding amine group and its conversion to diazonium cation at the electrode surface to yield a surface covalently modified with catechol. In this manner, some derivatives of catechol can be immobilized on the electrode surface. Whole of the process is carried out in Triethylammonium acetate ionic liquid as an inert and neutral medium (pH∼7.0). Surface coverage can be easily controlled by the applied potential, time and concentration of catechol. After modification, the electrochemical features of modified surface have been studied. Also modified GC electrode exhibited remarkable catalytic activity in the oxidation of NADH. The catalytic currents were proportional to the concentration of NADH over the range 0.01-0.80 mM. This condition can be used for modification of GC surfaces by various aromatic molecules for different application such as design of sensors and biosensors. © 2014 Elsevier Ltd. All rights reserved.

Post-exercise depression in corticomotor excitability after dynamic movement: a general property of fatiguing and non-fatiguing exercise

Transcranial magnetic stimulation has been used to study changes in central excitability associated with motor tasks. Recently, we reported that a finger flexion–extension task performed at a maximal voluntary rate (MVR) could not be sustained and that this was not due to muscle fatigue, but was more likely a breakdown in central motor control. To determine the central changes that accompany this type of movement task, we tracked motor-evoked potential (MEP) amplitude from the first dorsal interosseous (FDI) and abductor pollicis brevis (APB) muscles of the dominant hand in normal subjects for 20 min after a 10 sec index finger flexion–extension task performed at MVR and at a moderate sustainable rate (MSR) and half the MSR (MSR/2). The FDI MEP amplitude was reduced for up to 6–8 min after each of the tasks but there was a greater and longer-lasting reduction after the MSR and MSR/2 tasks compared to the MVR task. There was a similar reduction in the amplitude of the FDI MEP after a 10 sec cyclic index finger abduction–adduction task when the FDI was acting as the prime mover. The amplitude of the MEP recorded from the inactive APB was also reduced after the flexion–extension tasks, but to a lesser degree and for a shorter duration. Measurements of short-interval cortical inhibition revealed an increase in inhibition after all of the finger flexion–extension tasks, with the MSR task being associated with the greatest degree of inhibition. These findings indicate that a demanding MVR finger movement task is followed by a period of reduced corticomotor excitability and increased intracortical inhibition. However, these changes also occur with and are greater with slower rates of movement and are not specific for motor demand, but may be indicative of adaptive changes in the central motor pathway after a period of repetitive movement.

The National Perinatal Depression Initiative: An evaluation of access to general practitioners, psychologists and psychiatrists through the Medicare Benefits Schedule

OBJECTIVE: To evaluate the impact of the National Perinatal Depression Initiative on access to Medicare services for women at risk of perinatal mental illness. METHOD: Retrospective cohort study using difference-in-difference analytical methods to quantify the impact of the National Perinatal Depression Initiative policies on Medicare Benefits Schedule mental health usage by Australian women giving birth between 2006 and 2010. A random sample of women of reproductive age enrolled in Medicare who had not given birth where used as controls. The main outcome measures were the proportions of women giving birth each month who accessed a Medicare Benefits Schedule mental health items during the perinatal period (pregnancy through to the end of the first postnatal year) before and after the introduction of the National Perinatal Depression Initiative. RESULTS: The proportion of women giving birth who accessed at least one mental health item during the perinatal period increased from 88 to 141 per 1000 between 2007 and 2010. The difference-in-difference analysis showed that while there was an overall increase in Medicare Benefits Schedule mental health item access as a result of the National Perinatal Depression Initiative, this did not reach statistical significance. However, the National Perinatal Depression Initiative was found to significantly increase access in subpopulations of women, particularly those aged under 25 and over 34 years living in major cities. CONCLUSION: In the 2 years following its introduction, the National Perinatal Depression Initiative was found to have increased access to Medicare funded mental health services in particular groups of women. However, an overall increase across all groups did not reach statistical significance. Further studies are needed to assess the impact of the National Perinatal Depression Initiative on women during childbearing years, including access to tertiary care, the cost-effectiveness of the initiative, and mental health outcomes. It is recommended that new mental health policy initiatives incorporate a planned strategic approach to evaluation, which includes sufficient follow-up to assess the impact of public health strategies.

Patterns of general practitioner usage among Pacific people: indicative results from the Waikato Medical Care Survey 1991-2

AIMS: To report patterns of medical contact in a representative sample of Pacific people attending the general practitioner. METHODS: The data were drawn from a survey of general practice in the Waikato region representing a one per cent sample of all weekday encounters. In total, 12,833 patient encounter forms were completed. Just over one per cent of all encounters were recorded for patients of Pacific Islands background. RESULTS: Rates of medical contact for Pacific patients were lower-3.4 visits per year versus 4.5 for the whole sample-fewer follow up visits were requested (71% versus 76.2%), presentation was delayed (4.9 days from onset versus 3.7 for the sample) and there was an apparently lower level of rapport achieved. CONCLUSION: Overall levels of medical contact and return visits among Pacific patients appear to be lower and presentation delayed in this Waikato sample.

A general communication cost optimization framework for big data stream processing in geo-distributed data centers

With the explosion of big data, processing large numbers of continuous data streams, i.e., big data stream processing (BDSP), has become a crucial requirement for many scientific and industrial applications in recent years. By offering a pool of computation, communication and storage resources, public clouds, like Amazon's EC2, are undoubtedly the most efficient platforms to meet the ever-growing needs of BDSP. Public cloud service providers usually operate a number of geo-distributed datacenters across the globe. Different datacenter pairs are with different inter-datacenter network costs charged by Internet Service Providers (ISPs). While, inter-datacenter traffic in BDSP constitutes a large portion of a cloud provider's traffic demand over the Internet and incurs substantial communication cost, which may even become the dominant operational expenditure factor. As the datacenter resources are provided in a virtualized way, the virtual machines (VMs) for stream processing tasks can be freely deployed onto any datacenters, provided that the Service Level Agreement (SLA, e.g., quality-of-information) is obeyed. This raises the opportunity, but also a challenge, to explore the inter-datacenter network cost diversities to optimize both VM placement and load balancing towards network cost minimization with guaranteed SLA. In this paper, we first propose a general modeling framework that describes all representative inter-task relationship semantics in BDSP. Based on our novel framework, we then formulate the communication cost minimization problem for BDSP into a mixed-integer linear programming (MILP) problem and prove it to be NP-hard. We then propose a computation-efficient solution based on MILP. The high efficiency of our proposal is validated by extensive simulation based studies.

Learning clinical skills during bedside teaching encounters in general practice: a video-observational study with insights from activity theory

Purpose – This paper aims to explore how opportunities for learning clinical skills are negotiated within bedside teaching encounters (BTEs). Bedside teaching, within the medical workplace, is considered essential for helping students develop their clinical skills. Design/methodology/approach – An audio and/or video observational study examining seven general practice BTEs was undertaken. Additionally, audio-recorded, semi-structured interviews were conducted with participants. All data were transcribed. Data analysis comprised Framework Analysis informed by Engeström’s Cultural Historical Activity Theory. Findings – BTEs can be seen to offer many learning opportunities for clinical skills. Learning opportunities are negotiated by the participants in each BTE, with patients, doctors and students playing different roles within and across the BTEs. Tensions emerged within and between nodes and across two activity systems. Research limitations/implications – Negotiation of clinical skills learning opportunities involved shifts in the use of artefacts, roles and rules of participation, which were tacit, dynamic and changing. That learning is constituted in the activity implies that students and teachers cannot be fully prepared for BTEs due to their emergent properties. Engaging doctors, students and patients in refecting on tensions experienced and the factors that infuence judgements in BTEs may be a useful frst step in helping them better manage the roles and responsibilities therein. Originality/value – The paper makes an original contribution to the literature by highlighting the tensions inherent in BTEs and how the negotiation of roles and division of labour whilst juggling two interacting activity systems create or inhibit opportunities for clinical skills learning. This has signifcant implications for how BTEs are conceptualised.

You kind of want to fix it don’t you? Exploring general practice trainees’ experiences of managing patients with medically unexplained symptoms

Background
Much of a General Practitioner’s (GP) workload consists of managing patients with medically unexplained symptoms (MUS). GP trainees are often taking responsibility for looking after people with MUS for the first time and so are well placed to reflect on this and the preparation they have had for it; their views have not been documented in detail in the literature. This study aimed to explore GP trainees’ clinical and educational experiences of managing people presenting with MUS.
Method
A mixed methods approach was adopted. All trainees from four London GP vocational training schemes were invited to take part in a questionnaire and in-depth semi-structured interviews. The questionnaire explored educational and clinical experiences and attitudes towards MUS using Likert scales and free text responses. The interviews explored the origins of these views and experiences in more detail and documented ideas about optimising training about MUS. Interviews were analysed using the framework analysis approach.


Results

Eighty questionnaires out of 120 (67 %) were returned and a purposive sample of 15 trainees interviewed. Results suggested most trainees struggled to manage the uncertainty inherent in MUS consultations, feeling they often over-investigated or referred for their own reassurance. They described difficulty in broaching possible psychological aspects and/or providing appropriate explanations to patients for their symptoms. They thought that more preparation was needed throughout their training. Some had more positive experiences and found such consultations rewarding, usually after several consultations and developing a relationship with the patient.
Conclusion
Managing MUS is a common problem for GP trainees and results in a disproportionate amount of anxiety, frustration and uncertainty. Their training needs to better reflect their clinical experience to prepare them for managing such scenarios, which should also improve patient care.

Selecting, training and assessing new general practice community teachers in UK medical schools

Background: Standards for undergraduate medical education in the UK, published in Tomorrow’s Doctors, include the criterion ‘everyone involved in educating medical students will be appropriately selected, trained, supported and appraised’. Aims: To establish how new general practice (GP) community teachers of medical students are selected, initially trained and assessed by UK medical schools and establish the extent to which Tomorrow’s Doctors standards are being met. Method: A mixed-methods study with questionnaire data collected from 24 lead GPs at UK medical schools, 23 new GP teachers from two medical schools plus a semi-structured telephone interview with two GP leads. Quantitative data were analysed descriptively and qualitative data were analysed informed by framework analysis. Results: GP teachers’ selection is non-standardised. One hundred per cent of GP leads provide initial training courses for new GP teachers; 50% are mandatory. The content and length of courses varies. All GP leads use student feedback to assess teaching, but other required methods (peer review and patient feedback) are not universally used. Conclusions: To meet General Medical Council standards, medical schools need to include equality and diversity in initial training and use more than one method to assess new GP teachers. Wider debate about the selection, training and assessment of new GP teachers is needed to agree minimum standards.

A strategy for involving general practitioners in smoking control

OBJECTIVE: In 1991, the Victorian Smoking and Health Program introduced a simple intervention strategy for general practitioners that could be integrated conveniently and inexpensively into the routine care of patients who smoke. The aim of this study was to determine whether there had been a change over time in whether or not GPs advised their patients not to smoke. METHOD: The extent to which smokers remembered GPs talking to them about smoking was assessed in population-based surveys of adults in Victoria in 1990 (prior to the implementation of the intervention) and in 1992, 1994 and 1996. RESULTS: Over time there was a significant increase in the proportion of smokers who reported that their GP had provided them with help or information to stop smoking (chi 2 = 17.58, p < 0.001). In 1996, 9% of smokers said their doctor had advised them to contact Quit. CONCLUSION: Levels of recalled advice and provision of information regarding smoking cessation have increased by 10% over the past six years. However, nearly half the smokers in this study reported that they had been given inappropriate advice or no advice at all. IMPLICATIONS: A brief intervention by GPs, supplemented by appropriate referrals, has the potential to assist significant numbers of smokers to quit and may be more practical for GPs who are unable to personally provide all of the support smokers may need to quit.

Incident delirium in the acute general medical setting

 Delirium is a serious neuro‐cognitive disorder that affects many people admitted to hospital. Results of this research have contributed valuable knowledge regarding the risk factors, health outcomes and management of medical patients with who developed incident delirium during hospitalisation.

Health improvement and prevention study (HIPS) - evaluation of an intervention to prevent vascular disease in general practice

Background

The Health Improvement and Prevention Study (HIPS) study aims to evaluate the capacity of general practice to identify patients at high risk for developing vascular disease and to reduce their risk of vascular disease and diabetes through behavioural interventions delivered in general practice and by the local primary care organization.

Methods/Design

HIPS is a stratified randomized controlled trial involving 30 general practices in NSW, Australia. Practices are randomly allocated to an 'intervention' or 'control' group. General practitioners (GPs) and practice nurses (PNs) are offered training in lifestyle counselling and motivational interviewing as well as practice visits and patient educational resources. Patients enrolled in the trial present for a health check in which the GP and PN provide brief lifestyle counselling based on the 5As model (ask, assess, advise, assist, and arrange) and refer high risk patients to a diet education and physical activity program. The program consists of two individual visits with a dietician or exercise physiologist and four group sessions, after which patients are followed up by the GP or PN. In each practice 160 eligible patients aged between 40 and 64 years are invited to participate in the study, with the expectation that 40 will be eligible and willing to participate. Evaluation data collection consists of (1) a practice questionnaire, (2) GP and PN questionnaires to assess preventive care attitudes and practices, (3) patient questionnaire to assess self-reported lifestyle behaviours and readiness to change, (4) physical assessment including weight, height, body mass index (BMI), waist circumference and blood pressure, (5) a fasting blood test for glucose and lipids, (6) a clinical record audit, and (7) qualitative data collection. All measures are collected at baseline and 12 months except the patient questionnaire which is also collected at 6 months. Study outcomes before and after the intervention is compared between intervention and control groups after adjusting for baseline differences and clustering at the level of the practice.

Discussion

This study will provide evidence of the effectiveness of a primary care intervention to reduce the risk of cardiovascular disease and diabetes in general practice patients. It will inform current policies and programs designed to prevent these conditions in Australian primary health care.

Obesity impacts on general practice appointments

Objective: To quantify the impact of obesity on the number of visits to both primary and secondary care teams.

Research Methods and Procedures: The adult populations of 80 general practices throughout the United Kingdom were classified according to their BMI. We undertook a cross-sectional survey of computer-generated and handwritten records of 6150 obese people (BMI ≥ 30 kg/m2) and 1150 normal weight (BMI = 18.5 to 24.9 kg/m2) control subjects over an 18-month retrospective period.

Results: Obese patients made significantly more visits to the general practitioner (GP), practice nurse (PN), and hospital outpatient units than normal weight patients (all p < 0.001), and they were admitted to the hospital more often (p = 0.034). For both GP and PN visits, the relationship remained after adjusting for age, sex, social deprivation category, country, and number of comorbidities. Among obese patients, there was an increasing relationship between frequent GP visits (at least four appointments) and greater BMI, which remained significant after adjustment had been made for age, sex, deprivation, country, and number of comorbidities.

Discussion: The human resource burden to general practice is significantly higher in the obese population than in the normal weight population, even when adjusted for confounding factors. The increase in prevalence of obesity will continue to put pressure on GP and PN time unless appropriate action is taken.