Versteegh M.M.,Erasmus University Rotterdam |
Leunis A.,Erasmus University Rotterdam |
Luime J.J.,Rotterdam University |
Boggild M.,Walton Center |
And 2 more authors.
Medical Decision Making | Year: 2012
Background. Responses on condition-specific instruments can be mapped on the EQ-5D to estimate utility values for economic evaluation. Mapping functions differ in predictive quality, and not all condition-specific measures are suitable for estimating EQ-5D utilities. We mapped QLQC30, HAQ, and MSIS-29 on the EQ-5D and compared the quality of the mapping functions with statistical and clinical indicators. Methods. We used 4 data sets that included both the EQ-5D and a condition-specific measure to develop ordinary least squares regression equations. For the QLQ-C30, we used a multiple myeloma data set and a non-Hodgkin lymphoma one. An early arthritis cohort was used for the HAQ, and a cohort of patients with relapsing remitting or secondary progressive multiple sclerosis was used for the MSIS-29. We assessed the predictive quality of the mapping functions with the root mean square error (RMSE) and mean absolute error (MAE) and the ability to discriminate among relevant clinical subgroups. Pearson correlations between the condition-specific measures and items of the EQ-5D were used to determine if there is a relationship between the quality of the mapping functions and the amount of correlated content between the used measures. Results. The QLQ-C30 had the highest correlation with EQ-5D items. Average %RMSE was best for the QLQ-C30 with 10.9%, 12.2% for the HAQ, and 13.6% for the MSIS-29. The mappings predicted mean EQ-5D utilities without significant differences with observed utilities and discriminated between relevant clinical groups, except for the HAQ model. Conclusions. The preferred mapping functions in this study seem suitable for estimating EQ-5D utilities for economic evaluation. However, this research shows that lower correlations between instruments lead to less predictive quality. Using additional validation tests besides reporting statistical measures of error improves the assessment of predictive quality.
Chadwick D.,Walton Center |
Almond S.,Royal Liverpool Hospital
Practical Neurology | Year: 2010
The differential diagnosis of episodes of transient loss of consciousness can be straightforward but can also present some of the greatest diagnostic diffi culties. In most circumstances, when there is uncertainty, usually when there have been only one or a few poorly observed events, it may be reasonable to admit to that uncertainty and await any further events to clarify the diagnosis. We have reason to know from bitter experience that this is not always the case and that more rigorous consideration of investigation may be justifi ed rather than allowing the passage of time to clarify the diagnosis.
Goebel A.,University of Liverpool |
Goebel A.,Walton Center
Autoimmunity Reviews | Year: 2013
Complex regional pain syndrome (CRPS) is a painful condition, which arises in a limb after trauma. CRPS can profoundly affect patients' quality of life, and there is no cure. CRPS is associated with limb-confined sensory, motor, skin, bone and autonomic abnormalities. Recent research has shown that some patients respond to treatment with immunoglobulins, and that a majority have IgG serum-autoantibodies directed against, and activating autonomic receptors. CRPS serum-IgG, when transferred to mice elicits abnormal behaviour. These results suggest that CRPS is associated with an autoantibody-mediated autoimmune process in some cases. CRPS has unusual features, including a non-destructive, and regionally-confined course. We propose that CRPS constitutes a prototype of a new kind of autoimmunity, which we term 'IRAM' (injury-triggered, regionally-restricted autoantibody-mediated autoimmune disorder with minimally-destructive course). Understanding autoimmune contribution to CRPS should allow the exploration of novel treatment modalities in the future. Additional 'functional' disorders, painful or painless may be autoimmune in nature. © 2013 Elsevier B.V.
Maramattom B.V.,Lourdes Heart Institute and Neuro Center |
Jacob A.,Walton Center
Annals of Indian Academy of Neurology | Year: 2011
A large proportion of "encephalitis" is caused by unknown agents. Of late, a new category of disorders, "autoimmune encephalitis," has been described, which present with features similar to viral encephalitides. A well-delineated and common entity among this group is the recently described anti-NMDAR encephalitis (NMDARE). Although this entity was initially described in young women harboring ovarian teratomas, it is now characterised as well in children and men. Approximately 60% of the patients have an underlying tumor, usually an ovarian teratoma. In 40% of the patients, no cause can be found (idiopathic NMDARE). NMDARE typically presents with psychiatric features followed by altered level of consciousness, severe dysautonomia, hyperkinetic movement disorders, seizures and central hypoventilation. Orofacial dyskinesias resulting in lip and tongue mutilation are quite common. Seizures, are common and may be difficult to treat. The disease can be confirmed by serum and cerebrospinal fluid anti-NMDAR antibodies. Titers of these antibodies can also guide response to treatment. Tumor removal is necessary if identified, followed by immunological treatment. Intravenous methylprednisolone and immunoglobulins aim to suppress/modulate immune response while plasma exchange attempts to remove antibodies and other inflammatory cytokines. Rituximab and cyclophosphamide aim to suppress antibody production. Recovery is slow and often with neurological deficits if treatment is delayed. With many distinctive clinical features, a specific antibody that aids diagnosis, and early effective treatment with commonly available drugs leading to good outcomes, NMDARE is a diagnosis that should be considered early in any case of "unexplained encephalitis".
Barone D.G.,Walton Center |
Czosnyka M.,University of Cambridge
The Scientific World Journal | Year: 2014
The ability to measure reliably the changes in the physical and biochemical environment after a brain injury is of great value in the prevention, treatment, and understanding of the secondary injuries. Three categories of multimodal brain monitoring exist: direct signals which are monitored invasively; variables which may be monitored noninvasively; and variables describing brain pathophysiology which are not monitored directly but are calculated at the bedside by dedicated computer software. Intracranial pressure (ICP) monitoring, either as stand-alone value or study of a dynamic trend, has become an important diagnostic tool in the diagnosis and management of multiple neurological conditions. Attempts have been made to measure ICP non-invasively, but this is not a clinical reality yet. There is contrasting evidence that monitoring of ICP is associated with better outcome, and further RCTs based on management protocol are warranted. Computer bedside calculation of "secondary parameters" has shown to be potentially helpful, particularly in helping to optimize "CPP-guided therapy." In this paper we describe the most popular invasive and non invasive monitoring modalities, with great attention to their clinical interpretation based on the current published evidence. © 2014 D. G. Barone and M. Czosnyka.