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The Ministry of Health (MOH) has developed the clinical practice guidelines on Anxiety Disorders to provide doctors and patients in Singapore with evidence-based treatment for anxiety disorders. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the MOH clinical practice guidelines on anxiety disorders, for the information of SMJ readers. Chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Ministry of Health website: http://www.moh.gov.sg/content/moh_web/healthprofessionalsportal/doctors/guidelines/cpg_medical.html. The recommendations should be used with reference to the full text of the guidelines. Following this article are multiple choice questions based on the full text of the guidelines.

1.1 Background information

Anxiety disorders are known to be one of the most prevalent of psychiatric conditions, yet they often remain under-diagnosed and under-treated. Their chronic, disabling symptoms cause considerable burden not only to sufferers but also to their families, and contribute to poorer quality of life and considerable economic burden on society.In many instances, there is a delay in seeking treatment and in some cases such delay may stretch up to nearly ten years. This may result from ignorance of the condition, fear of taking medications, and the stigma of receiving a psychiatric diagnosis, and or having to accept psychiatric treatment.The anxiety disorders include panic disorder with or without agoraphobia, social anxiety disorder, specific phobia, obsessive-compulsive disorder, generalised anxiety disorder, acute stress disorder and post-traumatic stress disorder. In the clinical evaluation of anxiety disorders, it is important to ascertain the type of anxiety disorder present. This would allow treatment to be targeted at the specific type of disorder.These guidelines are developed to provide practical, evidence-based recommendations to primary care physicians and specialists in psychiatry for the diagnosis and management of the anxiety disorders.The first edition of the guidelines was published in 2003. In this edition, we present data from newer research as well as older data not previously reported in the earlier guidelines.For example, we examine the efficacy of combining medications with psychological therapy over medications alone, or psychological therapy alone. In view of the majority of anxiety sufferers being female we have made recommendations for pharmacotherapy during pregnancy and breastfeeding. As these guidelines are intended for use in the Singapore context, we have omitted treatments that are currently not available in Singapore.

1.2 Aim

These guidelines are developed to facilitate the diagnosis and assessment of the anxiety disorders, and to ensure that their management is appropriate and effective.

1.3 Scope

These guidelines will cover the management of anxiety disorders in adults and address the issues of medication use during pregnancy and breastfeeding.

1.4 Target group

The content of the guidelines will be useful for all doctors treating patients with anxiety disorders. Efforts have been made to ensure that the guidelines are particularly useful for primary care physicians and specialists in psychiatry, including all those involved in the assessment and management of patients with anxiety disorders in the community. The doctor treating the patient is ultimately responsible for clinical decisions made after reviewing the individual patient’s history, clinical presentation and treatment options available.

1.5 Development of guidelines

These guidelines have been produced by a committee of psychiatrists, a clinical psychologist, pharmacist, patient representative, and family practitioners appointed by the Ministry of Health. They were developed by revising the existing guidelines, reviewing relevant literature, including overseas clinical practice guidelines, and by expert clinical consensus of professionals with experience in treating patients in the local setting.The following principles underlie the development of these guidelines:
  • Treatment recommendations are supported by scientific evidence whenever possible (randomised controlled clinical trials represent the highest level of evidence) and expert clinical consensus is used when such data are lacking.
  • Treatment should maximise therapeutic benefits and minimise side effects.

1.6 What’s new in the revised guidelines

This edition of the guidelines contains updated recommendations based on latest evidence, as well as detailed discussions and recommendations on the management of anxiety disorders in adult populations.The following represent changes to the revised guidelines
  • An extensive review of the literature, including new evidence. This involved the re-writing and extensive revision of the chapters.
  • Length of treatment, which provides answers to a pertinent question.
  • Use of medications during pregnancy and breastfeeding. Given that females are more likely to be at risk of being diagnosed with anxiety disorders, this is an important subject.
We are aware that the Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5) was released in 2013. In DSM-5, post-traumatic stress disorder and obsessive-compulsive disorder have been removed and classified separately from the rest of the anxiety disorders. If we were to adhere strictly to DSM-5, this would entail omitting discussion on post-traumatic stress disorder and obsessive-compulsive disorder. As it is our aim to provide an update on the 2003 guidelines, post-traumatic stress disorder and obsessive-compulsive disorder have been included in this edition of the guidelines.In addition, anxiety conditions in children are included in DSM-5. Since the present guidelines are meant to address only adult anxiety disorders, guidelines on children’s anxiety conditions are not included here.Hence, for purposes of these guidelines, we will continue to use classifications based on the International Classification of Diseases-10 (ICD-10) and DSM-IV-TR criteria.

1.7 Review of guidelines

Evidence-based clinical practice guidelines are only as current as the evidence that supports them. Users must keep in mind that new evidence could supersede recommendations in these guidelines. The workgroup advises that these guidelines be scheduled for review five years after publication, or when new evidence appears that requires substantive changes to the present recommendations.  相似文献   
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Pancreatic islets adapt to insulin resistance through a complex set of changes, including β-cell hyperplasia and hypertrophy. To determine if islet vascularization changes in response to insulin resistance, we investigated three independent models of insulin resistance: ob/ob, GLUT4+/−, and mice with high-fat diet–induced obesity. Intravital blood vessel labeling and immunocytochemistry revealed a vascular plasticity in which islet vessel area was significantly increased, but intraislet vessel density was decreased as the result of insulin resistance. These vascular changes were independent of islet size and were only observed within the β-cell core but not in the islet periphery. Intraislet endothelial cell fenestration, proliferation, and islet angiogenic factor/receptor expression were unchanged in insulin-resistant compared with control mice, indicating that islet capillary expansion is mediated by dilation of preexisting vessels and not by angiogenesis. We propose that the islet capillary dilation is modulated by endothelial nitric oxide synthase via complementary signals derived from β-cells, parasympathetic nerves, and increased islet blood flow. These compensatory changes in islet vascularization may influence whether β-cells can adequately respond to insulin resistance and prevent the development of diabetes.Pancreatic islets are highly vascularized, and this feature is critical for β-cells to rapidly sense the blood glucose and secrete insulin into the systemic circulation (1,2). Islet vascularization begins early in pancreas development and is maintained in adulthood as a consequence of islet cell production of angiogenic factors such as vascular endothelial growth factor-A (VEGF-A) and angiopoietin-1 (Ang-1) (36). These factors recruit endothelial cells (ECs), stimulate blood vessel growth and maturation, and in the case of VEGF-A, promote formation of EC fenestrations (5,6). In addition, ECs adjacent to pancreatic epithelium reciprocally influence islet cell differentiation and development (7,8).β-Cells have a remarkable ability to respond to changes in an organism’s metabolic state, such as changes in the blood glucose or increased insulin requirements. For example, when insulin resistance develops, β-cells of the pancreatic islet can dramatically increase insulin production and secretion with an increase of β-cell mass, thus maintaining normoglycemia (9,10). In this way, mouse models with marked insulin resistance and humans with obesity-related insulin resistance are hyperinsulinemic but not hyperglycemic. The mechanisms underlying this β-cell adaptation to insulin resistance and their subsequent failure in some individuals who develop type 2 diabetes are incompletely understood.Because of the highly vascularized state of pancreatic islets and the marked changes in β-cell size and number in the setting of insulin resistance, we hypothesized that the islet vasculature must adapt to these changes in β-cell mass and insulin requirements. We envisioned that a hyperplastic islet, like a growing tumor mass, would increase production of angiogenic factors to increase its vascular supply with expanding β-cell mass (11). To test this hypothesis, we examined islet vascularization in three mouse models of insulin resistance and found, unexpectedly, that islet vessel density was decreased, not increased, and that the intraislet vasculature became markedly dilated whereas vessels in the exocrine tissue were unchanged. The dilation of intraislet capillaries was independent of islet size, suggesting the vascular adaptation may primarily support increased β-cell insulin secretory demand rather than β-cell mass expansion. Moreover, these vascular changes were accompanied by an increase in islet parasympathetic innervation. Our results indicate that the metabolic state influences islet angioarchitecture and innervation, suggesting that islet neurovascular remodeling may influence whether β-cells can adequately respond to insulin resistance and maintain normoglycemia.  相似文献   
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Although cognitive dysfunction is considered one of the more debilitating symptoms of schizophrenia, there is a fundamental gap in our knowledge of how the primary pharmacologic treatments of this disease, first- and second-generation antipsychotics (FGAs and SGAs, respectively), affect cognition, particularly over extended periods of time. Moreover, it has been known for decades that chronic treatment with FGAs can lead to imbalances in cholinergic function in the striatum that result in movement disorders; however, there is a growing body of evidence to suggest that both FGAs and SGAs can lead to cholinergic alterations in brain areas more traditionally considered as memory-related, such as cortical and hippocampal regions. Data from our laboratories in rodents indicate that some SGAs (if administered for sufficient periods of time) can be associated with impairments in memory-related task performance as well as alterations in the cholinergic enzyme choline acetyltransferase, the vesicular acetylcholine transporter, and nicotinic (alpha(7)) and muscarinic (M(2)) acetylcholine receptors. Given the well documented importance of central cholinergic function to information processing and cognitive function, it is important that the mechanisms for such chronic antipsychotic effects be identified. In this review, two potential mechanisms for long-term antipsychotic-related cholinergic alterations in the central nervous system are discussed: 1) antipsychotic antagonist activity at dopaminergic-D(2) receptors on cholinergic neurons and 2) antipsychotic effects on neurotrophins that support cholinergic neurons, such as nerve growth factor and brain derived growth factor. Novel strategies to optimize the therapeutics of schizophrenia and maintain cognitive function via adjunctive cholinergic compounds and antipsychotic crossover approaches are also discussed.  相似文献   
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Osseointegrated implants in craniofacial application: current status   总被引:1,自引:0,他引:1  
The success rates of craniofacial osseointegrated implants are not uniform throughout the craniofacial area. A better understanding of their clinical behaviour is needed. This article investigates current perspectives on the application of endosseous implants in the restoration of craniofacial defects. An online search was completed for the time period from 1966 to 2007, along with a manual search, to locate relevant peer-reviewed articles and textbooks published in English. A review of published reports of craniofacial application of endosseous implants in irradiated and nonirradiated tissue sites showed a strong correlation between anatomic sites and clinical success. Maxillofacial prosthetic considerations are also reviewed.  相似文献   
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