BackgroundNearly 1 in 10 in the population experience fatigue of more than six months at any one time. Chronic fatigue is a common reason for consulting a general practitioner, and some patients report their symptoms are not taken seriously enough. A gap in perceptions may occur because doctors underestimate the impact of fatigue on patients' lives. The main aim of the study is to explore the economic impact of chronic fatigue in patients seeking help from general practitioners and to identify characteristics that explain variations in costs.MethodsThe design of study was a survey of patients presenting to general practitioners with unexplained chronic fatigue. The setting were 29 general practice surgeries located in the London and South Thames regions of the English National Health Service. Use of services over a six month period was measured and lost employment recorded. Regression models were used to identify factors that explained variations in these costs.ResultsThe mean total cost of services and lost employment across the sample of 222 patients was £3878 for the six-month period. Formal services accounted for 13% of this figure, while lost employment accounted for 61% and informal care for 26%. The variation in the total costs was significantly related to factors linked to the severity of the condition and social functioning.ConclusionsThe economic costs generated by chronic fatigue are high and mostly borne by patients and their families. Enquiry about the functional consequences of fatigue on the social and occupational lives of patients may help doctors understand the impact of fatigue, and make patients feel better understood.
Abstract. An investigation of qualitative features of flows on manifolds, in terms of their attractors and quasi-attractors. A quasi-attractor is any nonempty intersection of attractors. It is shown that quasi-attractors other than attractors occur for a large set of flows. It is also shown that for a generic flow (for each flow in a residual subset of the set of all flows), each attractor "persists" as an attractor of all nearby flows. Similar statements are shown to hold with "quasi-attractor", "chain transitive attractor", and "chain transitive quasi-attractor" in place of "attractor". Finally, the set of flows under which almost all points tend asymptotically to a chain transitive quasi-attractor is characterized in terms of stable sets of invariant sets.0. Introduction. This paper investigates qualitative properties of attractors of flows on compact manifolds. An attractor of a flow, /, is a nonempty, compact, /-invariant set A that has a neighborhood, U, satisfying C\t>Qf(t, U) = A. The basin of attraction of the attractor A is the set of all points in the manifold that approach A asymptotically under the forward flow.The central concern is to determine when there is a collection of attractors of a given flow such that:(a) Each attractor in the collection is "indecomposable" in some sense.(b) Each of these attractors is "persistent" under perturbations of the flow.(c) The union of the basins of these attractors forms a dense subset in the manifold.The origin of the problem is a conjecture by R. Thorn: Conjecture [T, p. 39]. Given r > 1, there is a set of flows, S, residual in the set of all C flows on M, such that / £ S implies that / has a finite number of structurally stable, topologically transitive attractors whose basins are dense in M. Note that the attractors Thorn is talking about satisfy strong forms of the notions of "indecomposability" (topological transitivity) and "persistence" (structural stability). The primary examples of the exact situation Thom describes are the Axiom A and no cycles flows (see [S] or [N] for definitions), except of course that these flows do not in general form a residual subset. In the time since the original conjecture was made, a number of examples have shown that the conjecture needs
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