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The START (STrAtegies for RelaTives) intervention reduced depressive and anxiety symptoms of family carers of relatives with dementia at home over 2 years and was cost-effective.
To assess the clinical effectiveness over 6 years and the impact on costs and care home admission.
We conducted a randomised, parallel group, superiority trial recruiting from 4 November 2009 to 8 June 2011 with 6-year follow-up (trial registration: ISCTRN 70017938). A total of 260 self-identified family carers of people with dementia were randomised 2:1 to START, an eight-session manual-based coping intervention delivered by supervised psychology graduates, or to treatment as usual (TAU). The primary outcome was affective symptoms (Hospital Anxiety and Depression Scale, total score (HADS-T)). Secondary outcomes included patient and carer service costs and care home admission.
In total, 222 (85.4%) of 173 carers randomised to START and 87 to TAU were included in the 6-year clinical efficacy analysis. Over 72 months, compared with TAU, the intervention group had improved scores on HADS-T (adjusted mean difference −2.00 points, 95% CI −3.38 to −0.63). Patient-related costs (START versus TAU, respectively: median £5759 v. £16 964 in the final year; P = 0.07) and carer-related costs (median £377 v. £274 in the final year) were not significantly different between groups nor were group differences in time until care home (intensity ratio START:TAU was 0.88, 95% CI 0.58–1.35).
START is clinically effective and this effect lasts for 6 years without increasing costs. This is the first intervention with such a long-term clinical and possible economic benefit and has potential to make a difference to individual carers.
Declarations of interest
G.L., Z.W. and C.C. are supported by the UCLH National Institute for Health Research (NIHR) Biomedical Research Centre. G.L. and P.R. were in part supported by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) North Thames at Bart's Health NHS Trust. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. Z.W. reports during the conduct of the study; personal fees from GE Healthcare, grants from GE Healthcare, grants from Lundbeck, other from GE Healthcare, outside the submitted work.
The inverse barometer effect (IBE) is the isostatic response of ocean surface height to changes in atmospheric pressure (Pair) at a rate of about 1 cm hPa−1. The IBE is a significant contributor to variability of ice-shelf surface elevation (ηice), as we demonstrate with simultaneous global positioning system measurements of ηice and local measurements of Pair from the Amery, Brunt and Ross Ice Shelves, Antarctica. We find that an IBE correction is justified for frequencies (ω) covering the “weather band”, 0.03 < ω < 0.5 cpd (cycles per day). The IBE correction reduces the standard deviation of the weather-band signal of ηice from ∼9 cm to ∼3 cm. With this correction, the largest remaining high-frequency error signal in ηice is the inaccuracy of the present generation of Antarctic tide models, estimated to be of order 10 cm for most of Antarctica.
Reconciliation of unpaid care and employment is an increasingly important societal, economic and policy issue, both in the UK and internationally. Previous research shows the effectiveness of formal social care services in enabling carers to remain in employment. Using quantitative and qualitative data collected from carers and the person they care for in 2013 and 2015, during a period of cuts to adult social care in England, we explore barriers experienced to receipt of social care services. The main barriers to receipt of services identified in our study were availability, characteristics of services such as quality, and attitudes of carer and care-recipient to receiving services. These barriers have particular implications for carers' ability to reconcile care and employment.
This paper explores the effectiveness of paid services in supporting unpaid carers’ employment in England. There is currently a new emphasis in England on ‘replacement care’, or paid services for the cared-for person, as a means of supporting working carers. The international evidence on the effectiveness of paid services as a means of supporting carers’ employment is inconclusive and does not relate specifically to England. The study reported here explores this issue using the 2009/10 Personal Social Services Survey of Adult Carers in England. The study finds a positive association between carers’ employment and receipt of paid services by the cared-for person, controlling for covariates. It therefore gives support to the hypothesis that services for the cared-for person are effective in supporting carers’ employment. Use of home care and a personal assistant are associated on their own with the employment of both men and women carers, while use of day care and meals-on-wheels are associated specifically with women's employment. Use of short-term breaks are associated with carers’ employment when combined with other services. The paper supports the emphasis in English social policy on paid services as a means of supporting working carers, but questions the use of the term ‘replacement care’ and the emphasis on ‘the market’.
Many long-term care systems in economically developed countries are reliant on informal care. However, in the context of population ageing, there are concerns about the future supply of informal care. This article reports on projections of informal care receipt by older people with disabilities from spouses and (adult) children to 2032 in England. The projections show that the proportions of older people with disabilities who have a child will fall by 2032 and that the extent of informal care in future may be lower than previously estimated. The policy implications, in the context of the Dilnot Commission's report, are explored.
In England, Local Authorities (LAs) contribute to the care home fees of two-thirds of care home residents aged 65+ who pass a means test. LAs typically pay fees below those faced by residents excluded from state support. Most proposals for reform of the means test would increase the proportion of residents entitled to state support. If care homes receive the LA fee for more residents, they might increase fees for any remaining self-funders. Alternatively, the LA fee might have to rise. We use two linked simulation models to examine how alternative assumptions on post-reform fees affect projected public costs and financial gains to residents of three potential reforms to the means test. Raising the LA fee rate to maintain income per resident would increase the projected public cost of the reforms by between 22% and 72% in the base year. It would reduce the average gain to care home residents by between 8% and 12%. Raising post-reform fees for remaining self-funders or requiring pre-reform self-funders to meet the difference between the LA and self-funder fees, reduces the gains to residents by 28–37%. For one reform, residents in the highest income quintile would face losses if the self-funder fee rises.
Boron diffusion in Sia7 Gea3 strained layers has been studied as a function of annealing temperature and is compared to boron diffusion in unstrained Si epitaxial layers. A lower diffusivity was observed in Sia7 Gea3 strained layers as compared to the Si control samples. Using the well-accepted model for boron diffusion via charged point defects in Si, the intrinsic diffusivities of the boron atoms in the Sia7 Gea3 layers were derived and an activation energy of 4.4 eV was estimated for the diffusion process.
A new approach to describe the diffusion process is also presented here. In this model, we relate the lower diffusivity to a corresponding change in the charged point defect equilibrium concentration caused by a change in band-gap due to the strain and the existence of foreign atoms in a Si matrix.
The future market costs of long-term care for older people will be affected by the extent of informal care. This paper reports on projections of receipt of informal care by disabled older people from their spouses and (adult) children to 2031 in England. The paper shows that, over the next 30 years, care by spouses is likely to increase substantially. However, if current patterns of care remain the same, care by children will also need to increase by nearly 60 per cent by 2031. It is not clear that the supply of care by children will rise to meet this demand.
Using two linked simulation models, we examine the public expenditure costs and distributional effects of potential reforms to long-term care funding in the UK. Changes to the means tests for user contributions to care costs are compared with options for the abolition of these means tests (‘free’ personal care). The latter generally cost more than the former and benefit higher income groups more than those on lower incomes (measuring income in relation to the age-specific income distribution). Reforms to the means tests target benefits towards those on lower incomes. However, the highest income group are net losers if free personal care is financed by a higher tax rate on higher incomes and the effect on the whole population considered.
Several factors are thought to influence resource use and costs in treating schizophrenia.
To assess the relative impact of non-adherence and other factors associated with resource use and costs incurred by people with schizophrenia.
Secondary analyses were made of data from a 1994 national survey of psychiatric morbidity among adults living in institutions in the UK. Factors potentially relating to resource use and costs were examined using two-part models.
Patients who failed to adhere to their medication regimen were over one-and-a-halftimes as likely as patients who did adhere to it to report use of in-patient services. Non-adherence is one of the most significant factors in increasing external service costs, by a factor of almost 3. Non-adherence predicted an excess annual cost per patient of approximately $2500 for in-patient services and over $5000 for total service use.
Resource use and costs are influenced by various factors. Medication non-adherence consistently exhibits an association with higher costs. Further important factors are patient needs and the ability of the system to address them.
All accreting matter, like most of the material in the Universe, is in a gaseous form. This means that the constituent particles, usually free electrons and various species of ions, in teract directly only by collisions, rather than by more complicated short-range forces. In fact, these collisions involve the electrostatic interaction of the particles and will be considered in more detail in Chapter 3. On average, a gas particle will travel a certain distance, the mean free path, λ, before changing its state of motion by colliding with another particle. If the gas is approximately uniform over lengthscales exceeding a few mean free paths, the effect of all these collisions is to randomize the particle velocities about some mean velocity, the velocity of the gas, v. Viewed in a reference frame moving with velocity v, the particles have a Maxwell–Boltzmann distribution of velocities, and can be described by a temperature T. Provided we are interested only in lengthscales L ≫ λ we can regard the gas as a continuous fluid, having velocity v, temp erature T and density ρ defined at each point. We then study the behaviour of these and other fluid variables as functions of position and time by imposing the laws of conservation of mass, momentum and energy. This is the subject of gas dynamics. If we wish to look more closely at the gas, we have to consider the particle interactions in more detail; this is the domain of plasma physics, or, more strictly, plasma kinetic theory, about which we shall have something to say in Chapter 3.
In previous chapters we have discussed extensively the theory and applications of thin (H ≪ R) accretion discs. We hope the reader will by now be convinced that this theory is reasonably well understood, and that it rests on a fairly firm observational basis. The case for thick (H ∼ R) accretion discs however is less compelling as the theory is still under development and the relevant observations are few, difficult and indirect. Furthermore, since the publication of the first papers on equilibrium thick discs or tori much work has been done on extending these solutions allowing some form of poloidal flow and studying extensively their dynamical stability. The wealth of these investigations is a testimony to the interest generated by these structures. The results obtained so far virtually rule out the reality of thick discs as non-accreting toroidal equilibria but leave open the more exciting possibility of the existence of closely related accreting flows which could be of astrophysical interest. We begin here by discussing the toroidal equilibria without accretion and summarize the stability results at the end of this chapter. More recent and more general solutions with radial and other poloidal flows are discussed in Chapter 11.
The current interest in the theory of the structure, evolution and stability of thick accretion discs is due to the possibility that thick discs may be relevant to the understanding of the central power sources in radio galaxies and quasars (see Chapters 7–9).
We have seen in the foregoing chapters that a huge variety of accretion flows are at least theoretically possible. The equations describing axially symmetric flows with gravity, pressure and rotation allow a wide array of solutions of astrophysical interest. If one includes Ω = 0 (no rotation) as a special case, then even ordinary stars and spherically symmetrical Bondi accretion are solutions. More realistically, accretion flows with low angular momentum may produce supersonic flows which shock at smaller radii if they lack pressure support, or produce settling, cooling solutions if partially supported by pressure. We have already studied in detail spherically symmetrical accretion, the standard thin disc, and thick discs, and we will study other solutions which have acquired recognition in the astrophysical literature, such as slim discs and advection dominated accretion flows (ADAFs). In this chapter we shall attempt to organize all the different solutions into a coherent picture in order to clarify their relation to each other.
The fact that black holes possess an event horizon instead of a hard surface makes the inner boundary condition for black hole accretion flows qualitatively different from that for a normal star, and allows the existence of a family of solutions in which a significant fraction of the dissipated energy is advected through the horizon. Hence, for an external distant observer, ADAFs on to black holes are characterized by a low radiative efficiency η. (In ADAFs on to objects with a hard surface the advected energy must be ultimately reprocessed and released near the surface – see Section 11.8.3.)
In the years since the first edition of this book appeared the study of astrophysical accretion has developed rapidly. Perhaps the most fundamental change has been the shift in attitude over active galaxies and quasars: the view that accretion is the energy source is now effectively standard, and the emphasis is much more on close comparison of observation and theory. This change, and the less spectacular but still profound one which has occurred in the study of close binary accretion, have been largely brought about by the wealth of new data accumulated in the interval. In X-rays, the ability of EXOSAT to observe continuously for as much as 3 to 4 days was a dramatic advance. In the optical, new instrumentation has produced far tighter observational constraints on theory. Despite these challenges, the basic outlines of the theory are still recognizably the same.
Of course our understanding is very incomplete. As the most glaring example, we still have essentially no idea what drives disc accretion; and there are new problems such as the dynamical stability of thick discs, or the nature of fieldline threading in magnetic binaries. But it is now difficult to deny that some close binaries possess discs approximately conforming to theoretical ideas; or that some kind of anisotropic accretion occurs in active galactic nuclei. Encouragingly, accretion theory is increasingly integrated into wider pictures of the relevant systems. The process is well advanced for close binaries, particularly for the secular evolution of cataclysmic variables, and is in its early stages for active galaxies.
Whenever we need to consider the behaviour of a gas on lengthscales comparable to the mean free path between collisions, we must use the ideas of plasma physics. In this chapter we shall briefly introduce some of the concepts that will be important to our study of accretion.
A plasma differs from an atomic or molecular gas in that it consists of a mixture of two gases of electrically charged particles: an electron gas and an ion gas, with very different particle masses me and mi.
The electrons and ions interact with each other through their electrostatic Coulomb attractions and repulsions. These Coulomb forces decrease only slowly (∞ r-2) with distance and do not have a characteristic lengthscale. Thus, a plasma particle interacts with many others at any one instant, and this makes the description of collisions more complicated than in atomic or molecular gases, where the interparticle forces are very short-range. A further complication arises from the great difference in particle masses me and mi. Since collisions between particles of very different masses can transfer only a small fraction of the kinetic energy of order me/mi ≪ 1, it is possible for electrons and ions to have significantly different temperatures over appreciable timescales. These two properties – the long-range nature of the Coulomb force and the disparity in electron and ion masses – give the physics of plasmas its particular character. A further series of complex phenomena occurs when the plasma is permeated by a large-scale magnetic field; this is particularly relevant for the study of gas accreting on to highly magnetized neutron stars and white dwarfs.