La depresión y su relación con el deterioro cognitivo leve y la enfermedad de Alzheimer. Un estudio de revisión sistemática

The objective of the present study was to determine whether depression precedes Mild cognitive impairment (MCI) as a risk factor or as a predictor in Alzheimer's disease (AD). A systematic review of observational studies (cross-sectional and cohort or follow-up) was carried out using the PRISMA search algorithm, for clinical markers in MCI and AD, in the Science Direct, Springer, Scopus and Proquest databases. The study eligibility criteria included inclusion criteria: of types of documents, articles of primary studies, type of source scientific journals, published in the English language, from January 2010 to April 2020, in patients with MCI and AD and in the group of age included in people with a minimum age range of 45 years. Exclusion criteria were: publications older than 10 years because the aim of the article was to explore recent studies, secondary research studies, type of report document, languages other than English. 3385 articles were identified, of which 30 articles were finally selected. It was found that there is an association between depression and AD, but properly as a risk factor but not, as a predictor or clinical marker of the development of AD. The degree of association is greater when they present depressive symptoms and simultaneously report subjective memory complaints or the presence of MCI.     

Pharmacologic management of refractory depression.

OBJECTIVE: To review published clinical trials of the pharmacologic management of refractory depression. DATA SOURCES: MEDLINE was searched for relevant articles published from 1983 to 1990. The bibliographies of review articles were searched for additional references. Studies of nonpharmacologic treatments, such as electroconvulsive therapy, were not included. STUDY SELECTION: Eleven studies were found that did not contain obvious digressions from several methodologic assessment criteria (adapted from the McMaster guidelines for the evaluation of clinical trials). Further scrutiny by a nonblind reviewer resulted in the selection of four reports that were considered acceptable. An assessment by a second reviewer, blind as to author, results and journal name, confirmed this judgement. DATA EXTRACTION: Data describing response to the treatments were extracted by a single (nonblind) reviewer. Post-hoc power estimates and 95% confidence intervals were calculated whenever possible. DATA SYNTHESIS: The efficacy of augmenting an antidepressant regimen with lithium carbonate, triiodothyronine or reserpine was not supported by findings from the clinical trials reviewed. However, many trials with negative results lacked adequate statistical power to exclude the possibility of the drug''s efficacy. The use of a monoamine oxidase inhibitor was supported by the one study that met the review''s methodologic criteria. However, this study was not conducted under double-blind conditions. CONCLUSION: The generally recommended strategies for the pharmacologic treatment of refractory depression are not supported by methodologically sound studies.     

The vexed question of authorship: views of researchers in a British medical faculty.

OBJECTIVE: To assess knowledge, views, and behaviour of researchers on criteria for authorship and causes and control of gift authorship. DESIGN: Interview survey of stratified sample of researchers. SETTING: University medical faculty. SUBJECTS: 66 staff (94% response rate) comprising several levels of university academic and research appointments. MAIN OUTCOME MEASURES: Awareness and use of criteria for authorship, views on which contributions to research merit authorship, perceptions about gift authorship and strategies for reducing it, and experiences of authorship problems. RESULTS: 50 (76%) respondents supported criteria for authorship, but few knew about or used available criteria. Of the five people who could specify all three criteria of the International Committee of Medical Journal Editors, only one knew that all criteria had to be met. Forty one respondents (62%) disagreed with this stipulation. A range of practical and academic contributions were seen as sufficient for authorship. Gift authorship was perceived as common, promoted by pressure to publish, to motivate research teams, and to maintain working relationships. A signed statement justifying authorship and a published statement of the contribution of each author were perceived as practical ways of tackling gift authorship. Most researchers had experienced problems with authorship, most commonly the perception that authorship had been deserved but not awarded (49%). CONCLUSION: There seems to be a gap between editors'' criteria for authorship and researchers'' practice. Lack of awareness of criteria is only a partial explanation. Researchers give more weight than editors to practical research contributions. Future criteria should be agreed by researchers and not be imposed by editors.     

Effects of botanical dietary supplements on cardiovascular,cognitive, and metabolic function in males and females

Background: The onset of menopause marks a pivotal time in which the incidence of hypertension and of cardiovascular disease (CVD) begins to increase dramatically in women. Before menopause, the incidences of these diseases are significantly lower in women than in age-matched men. After menopause, the rates of these diseases in women eventually approximate those in men. The loss of endogenous estrogen at menopause has been traditionally believed to be the primary factor involved in these changes.Objective: This review summarizes recent findings regarding the effectiveness of botanicals in the treatment of some menopausal symptoms and other symptoms of aging (eg, rise in arterial pressure, cognitive decline, insulin resistance, and hyperlipidemia).Methods: Articles were selected for inclusion in this review based on the significance of the research and contribution to the current understanding of how each botanical elicits cardioprotective effects. To this end, PubMed and MEDLINE databases were searched, using terms that included the name of the specific botanical along with the relevant aspects of its action(s), such as blood pressure, glycemic control, and lipids. Most of the articles used were published within the past 5 years, although some older articles that were seminal in advancing the current understanding of botanicals were also included.Results: Soy has been found to lower plasma lipid concentrations and arterial pressure in postmenopausal women and age-matched men, and to have protective effects in heart disease and atherosclerosis of the carotid and coronary circulation. Soy was also found to lower fasting insulin concentrations and glycosylated hemoglobin concentrations. Grape seed extract, another frequently used botanical, contains polyphenols that have been found to reduce arterial pressure and salt-sensitive hypertension in estrogendepleted animal models.Conclusion: Several botanical compounds have been found to have beneficial effects in the treatment of the symptoms of menopause and other symptoms of aging, including CVD, cognitive decline, and metabolic diseases.     

Promotional tone in reviews of menopausal hormone therapy after the Women's Health Initiative: an analysis of published articles

Background

Even after the Women''s Health Initiative (WHI) found that the risks of menopausal hormone therapy (hormone therapy) outweighed benefit for asymptomatic women, about half of gynecologists in the United States continued to believe that hormones benefited women''s health. The pharmaceutical industry has supported publication of articles in medical journals for marketing purposes. It is unknown whether author relationships with industry affect promotional tone in articles on hormone therapy. The goal of this study was to determine whether promotional tone could be identified in narrative review articles regarding menopausal hormone therapy and whether articles identified as promotional were more likely to have been authored by those with conflicts of interest with manufacturers of menopausal hormone therapy.

Methods and Findings

We analyzed tone in opinion pieces on hormone therapy published in the four years after the estrogen-progestin arm of the WHI was stopped. First, we identified the ten authors with four or more MEDLINE-indexed reviews, editorials, comments, or letters on hormone replacement therapy or menopausal hormone therapy published between July 2002 and June 2006. Next, we conducted an additional search using the names of these authors to identify other relevant articles. Finally, after author names and affiliations were removed, 50 articles were evaluated by three readers for scientific accuracy and for tone. Scientific accuracy was assessed based on whether or not the findings of the WHI were accurately reported using two criteria: (1) Acknowledgment or lack of denial of the risk of breast cancer diagnosis associated with hormone therapy, and (2) acknowledgment that hormone therapy did not benefit cardiovascular disease endpoints. Determination of promotional tone was based on the assessment by each reader of whether the article appeared to promote hormone therapy. Analysis of inter-rater consistency found moderate agreement for scientific accuracy (κ = 0.57) and substantial agreement for promotional tone (κ = 0.65). After discussion, readers found 86% of the articles to be scientifically accurate and 64% to be promotional in tone. Themes that were common in articles considered promotional included attacks on the methodology of the WHI, arguments that clinical trial results should not guide treatment for individuals, and arguments that observational studies are as good as or better than randomized clinical trials for guiding clinical decisions. The promotional articles we identified also implied that the risks associated with hormone therapy have been exaggerated and that the benefits of hormone therapy have been or will be proven. Of the ten authors studied, eight were found to have declared payment for speaking or consulting on behalf of menopausal hormone manufacturers or for research support (seven of these eight were speakers or consultants). Thirty of 32 articles (90%) evaluated as promoting hormone therapy were authored by those with potential financial conflicts of interest, compared to 11 of 18 articles (61%) by those without such conflicts (p = 0.0025). Articles promoting the use of menopausal hormone therapy were 2.41 times (95% confidence interval 1.49–4.93) as likely to have been authored by authors with conflicts of interest as by authors without conflicts of interest. In articles from three authors with conflicts of interest some of the same text was repeated word-for-word in different articles.

Conclusion

There may be a connection between receiving industry funding for speaking, consulting, or research and the publication of promotional opinion pieces on menopausal hormone therapy. Please see later in the article for the Editors'' Summary     

Early detection of depression by primary care physicians.

The overall prevalence of depression is from 3.5% to 27%. The burden of suffering is high and includes death through suicide. In most cases treatment is effective, but important episodes of depression are being missed. To determine whether a brief, systematic assessment for the early detection of depression should be part of the periodic health examination we searched MEDLINE and the Science Citation Index for randomized controlled trials that evaluated the effectiveness of early detection of depression with a questionnaire. Seven instruments met our quality criteria; the Beck Depression Inventory, the Center for Epidemiologic Studies Depression Scale, the Zung Self-Assessment Depression Scale, the General Health Questionnaire, the Hopkins Symptom Checklist, the Mental Health Inventory and the Hospital Anxiety and Depression Scale. The four randomized controlled trials failed to provide adequate evidence of the benefit of routine screening. Early detection is difficult because of depression''s natural history, the role of symptoms, the cultural diversity of Canada and how detection instruments have been developed. Depression deserves careful attention from primary care physicians; however, further research and development is required before the widespread routine use of any detection test can be recommended.     

A critical synthesis of literature on the promoting action on research implementation in health services (PARIHS) framework

Background

The Promoting Action on Research Implementation in Health Services framework, or PARIHS, is a conceptual framework that posits key, interacting elements that influence successful implementation of evidence-based practices. It has been widely cited and used as the basis for empirical work; however, there has not yet been a literature review to examine how the framework has been used in implementation projects and research. The purpose of the present article was to critically review and synthesize the literature on PARIHS to understand how it has been used and operationalized, and to highlight its strengths and limitations.

Methods

We conducted a qualitative, critical synthesis of peer-reviewed PARIHS literature published through March 2009. We synthesized findings through a three-step process using semi-structured data abstraction tools and group consensus.

Results

Twenty-four articles met our inclusion criteria: six core concept articles from original PARIHS authors, and eighteen empirical articles ranging from case reports to quantitative studies. Empirical articles generally used PARIHS as an organizing framework for analyses. No studies used PARIHS prospectively to design implementation strategies, and there was generally a lack of detail about how variables were measured or mapped, or how conclusions were derived. Several studies used findings to comment on the framework in ways that could help refine or validate it. The primary issue identified with the framework was a need for greater conceptual clarity regarding the definition of sub-elements and the nature of dynamic relationships. Strengths identified included its flexibility, intuitive appeal, explicit acknowledgement of the outcome of 'successful implementation,' and a more expansive view of what can and should constitute 'evidence.'

Conclusions

While we found studies reporting empirical support for PARIHS, the single greatest need for this and other implementation models is rigorous, prospective use of the framework to guide implementation projects. There is also need to better explain derived findings and how interventions or measures are mapped to specific PARIHS elements; greater conceptual discrimination among sub-elements may be necessary first. In general, it may be time for the implementation science community to develop consensus guidelines for reporting the use and usefulness of theoretical frameworks within implementation studies.     

Activities of Daily Living,Depression, and Quality of Life in Parkinson's Disease

This study examined whether activities of daily living (ADL) mediate the relationship between depression and health-related quality of life (HR-QOL) in people with Parkinson''s disease (PD). A cross-sectional, correlational research design examined data from 174 participants who completed the Geriatric Depression Scale (GDS-15), Parkinson''s Disease Questionnaire-39 (PDQ-39), and Unified Parkinson''s Disease Rating Scale-section 2 (UPDRS-section 2 [ADL]). Multiple Regression Analysis (MRA) was used to examine the mediator model. Depression and ADL significantly (p<.001) predicted HR-QOL, and depression significantly (p<.001) predicted ADL. Whilst ADL did not impact on the relationship between depression and HR-QOL, there was a significant (p<.001) indirect effect of depression on HR-QOL via ADL, suggesting both direct and indirect (via ADL) effects of depression on HR-QOL. The magnitude of this effect was moderate (R ² = .13). People with PD who report depression also experience greater difficulty completing ADL, which impacts upon their HR-QOL. It is recommended that clinicians adopt a multidisciplinary approach to care by combining pharmacological treatments with psycho/occupational therapy, thereby alleviating the heterogeneous impact of motor and non-motor symptoms on HR-QOL in people with PD.     

Association of Serum 25-Hydroxyvitamin D with Symptoms of Depression After 6 Months in Stroke Patients

Our aim was to determine whether there was a relationship between 25-hydroxyvitamin D (25[OH] D) and post-stroke depression (PSD). Two hundred and forty-four ischemic stroke patients admitted to the hospital within the first 24 h after stroke onset were consecutively recruited and followed up for 6 months. Clinical information was collected. Serum 25[OH] D levels were measured at baseline. Based on the symptoms, diagnoses of depression were made in accordance with DSM-IV criteria for depression at 6-month after stroke. At 6-month, 91 patients (37.3 %) showed depression and in 60 patients (24.6 %) this depression was classified as major. There was a significant difference in median serum 25[OH] D levels between PSD patients and no depression cases [8.3 (IQR, 6.8–9.5) vs. 15.6 (IQR, 13.2–20.3) ng/ml, respectively; P < 0.001]. Serum 25[OH] D levels ≤11.2 ng/ml were independently associated with PSD [odds ratio 10.32, 95 % confidence interval 4.97–28.63; P < 0.001], after adjusting for possible confounders. Serum 25[OH] D levels reduced at admission was found to be associated with PSD. Additional research is needed on vitamin D supplementation to improve the outcome of patients with PSD.     

Novel polymerase chain reaction-restriction fragment length polymorphism assay to determine internal transcribed spacer-2 group in the Chagas disease vector,Triatoma dimidiata (Latreille, 1811)

Triatoma dimidiata is the most important Chagas disease insect vector in Central America as this species is primarily responsible for Trypanosoma cruzi transmission to humans, the protozoan parasite that causes Chagas disease. T. dimidiata sensu lato is a genetically diverse assemblage of taxa and effective vector control requires a clear understanding of the geographic distribution and epidemiological importance of its taxa. The nuclear ribosomal internal transcribed spacer 2 (ITS-2) is frequently used to infer the systematics of triatomines. However, oftentimes amplification and sequencing of ITS-2 fails, likely due to both the large polymerase chain reaction (PCR) product and polymerase slippage near the 5'' end. To overcome these challenges we have designed new primers that amplify only the 3''-most 200 base pairs of ITS-2. This region distinguishes the ITS-2 group for 100% of known T. dimidiata haplotypes. Furthermore, we have developed a PCR-restriction fragment length polymorphism (RFLP) approach to determine the ITS-2 group, greatly reducing, but not eliminating, the number of amplified products that need to be sequenced. Although there are limitations with this new PCR-RFLP approach, its use will help with understanding the geographic distribution of T. dimidiata taxa and can facilitate other studies characterising the taxa, e.g. their ecology, evolution and epidemiological importance, thus improving vector control.     

Why don't we use vitamin E in dermatology?

OBJECTIVE: To review the possible uses of topical and systemic tocopherols as therapy for skin conditions in light of the widespread use of vitamin E by patients. DATA SOURCES: Index Medicus was searched for articles published from 1922 (when vitamin E was discovered) to 1966 (the beginning of MEDLINE). MEDLINE was searched for articles in English and French on vitamin E or tocopherol in relation to dermatology. Additional original articles were identified from the reference lists of the review articles. STUDY SELECTION: Only well-designed controlled studies were accepted; anecdotes and open studies are cited for completeness and as direction for future research. DATA SYNTHESIS: There was some weak or conflicting evidence that vitamin E is of value in yellow nail syndrome, vibration disease, epidermolysis bullosa, cancer prevention, claudication, cutaneous ulcers, and collagen synthesis and wound healing. It was of no use in atopic dermatitis, dermatitis herpetiformis, psoriasis, subcorneal pustular dermatosis, porphyrias and skin damage induced by ultraviolet light. CONCLUSIONS: After 44 years of research there is still scant proof of vitamin E''s effectiveness in treating certain dermatologic conditions. Further research in well-designed controlled trials is needed to clarify vitamin E''s role.     

'Positive biology' as a new paradigm for the medical sciences. Focusing on people who live long, happy, healthy lives might hold the key to improving human well-being

The nearly exclusive focus on understanding and treating chronic disease might not be the most efficient way to improve public health, especially as an effective alternative strategy exists.On 27 April 2009, during a speech at the National Academy of Sciences, US President Barack Obama pledged to invest more than 3% of US GDP in scientific research and development—the amount represented the largest ever investment in research and innovation. However, even a financial investment of such magnitude does not ensure that science is ''well-ordered'' [1], in the sense that the scientific research that is prioritized aspires to address the most significant challenges and problems for humanity.Among the many issues facing society that research must address, improving human health and tackling disease rank high, if not first, on the agenda. Accordingly, a huge fraction of research funding is spent on basic and applied research to further our understanding of the causes of disease and to find new cures and therapies. But is this focus on pathology the most efficient way to conduct research with the aim to improve human health and well-being?…a huge fraction of research funding is spent on basic and applied research to further our understanding of the causes of disease and to find new cures and therapiesMost of today''s medical research could be called ''negative biology''. It is conducted in an intellectual framework that presumes that the most important question to answer is: what causes pathology? Disease is its central focus and this explains why medical research and research funding is mainly concerned with trying to understand, prevent and treat specific diseases. The design of the US National Institutes of Health, which is largely composed of individual institutes dedicated to specific diseases such as cancer, mental illness or infectious diseases, reflects this prevalence of pathology-oriented negative biology.Positive biology, by contrast, focuses on a different set of questions and priorities. Rather than making pathology and disease the central focus of intellectual efforts and financial investments, positive biology seeks to understand positive phenotypes: why do some individuals live more than a century without ever suffering from the chronic diseases that afflict most humans much earlier in their lives? Why are some individuals more happy, optimistic, talented, or have a better memory than most people? The paradigm of positive biology is based on the insight that the process of evolution by natural selection does not create a perfect organism in terms of life expectancy, resistance to disease or other abilities. Observations of exceptional longevity or superior cognition therefore present fascinating puzzles for positive biology: which biological mechanisms would explain these exemplars of health and well-being? The goal of understanding positive phenotypes is that such knowledge might lead to new interventions that generally improve human well-being. This might be achieved by modulating the rate of ageing or by increasing opportunities for play and joy at all stages of the human lifespan, or by developing pharmaceuticals that safely enhance cognition or positive emotions, and so on.The goal of understanding positive phenotypes is that such knowledge might lead to new interventions that generally improve human well-beingThis is distinct from negative biology, which focuses on the proximate causes of specific diseases, rather than on the evolutionary causes of positive phenotypes. It presumes that health, survival and happiness are the default states and aims to explain the deviations: why do we develop cancer? Why do we suffer from depression? Why do we develop hypertension? Negative biology therefore faces the laudable but insurmountable task of trying to prevent or cure all disease. This is a costly and ultimately futile endeavour. Eliminating all types of cancer would increase life expectancy in the USA by approximately only three years [2]. Even eliminating cancer as a cause of death would not prevent any of the other chronic diseases of ageing—cardiovascular disease, Alzheimer and Parkinson disease, diabetes and so on—from afflicting the elderly. Moreover, the more than 40 years of ''war against cancer'' has not defeated a single type of cancer: we still have a long way to go before we can realistically expect to reap the three-year increase in life expectancy that eliminating all cancers could yield.In fact, negative biology has not yet developed a single cure for any one of the hundreds of chronic diseases that afflict millions of people living today. Of course, it has made significant advances to help prevent and treat chronic disease, but the fixation on pathology has meant that other potential avenues for research have been neglected.Indeed, a better understanding of exemplars of health and happiness—the goal of positive biology—could create more benefits for humans more quickly and more easily. A drug that would safely mimic the effects of caloric restriction, for instance, might delay, simultaneously, most diseases and afflictions of ageing. It would generate a much greater health dividend for ageing populations than defeating any one specific disease of ageing because slowing down the rate of ageing by seven years would reduce the age-specific risk of death, frailty and disability by about half at every age [3].Scientists are already making good progress on the project of positive biology, even if the intellectual framework is not yet clearly defined and their topics are rather piecemeal. Richard Miller, for example, a professor of pathology at Michigan University, USA, studies the genetics of ageing in mice and participates in the National Institute of Aging''s multi-institutional programme that evaluates the effects of drugs and nutriceuticals on the ageing process in mice. David Sinclair from Harvard University, USA, and others found that the plant compound resveratrol, which is found in the skin of grapes, can modulate the ageing process. Nir Barzilai and colleagues at the Albert Einstein School of Medicine in New York, USA, have conducted genetic research on more than 500 healthy elderly people between the ages of 95 and 112 years. Michael Rose from the University of California, Irvine, USA, has quadrupled the lifespan of fruit flies by delaying the age of reproduction. Finally, the biologist Cynthia Kenyon demonstrated that in Caenorhabditis elegans, a single gene can control the ageing process. Any of these research projects could eventually lead to the development of a new drug that retards the ageing process and diminishes the onslaught of chronic diseases that typically afflict humans after their sixth decade of life.Similarly, a lot of pioneering work is being undertaken in the burgeoning field of ''positive psychology''. Rather than studying why people suffer from mental illnesses such as depression, schizophrenia or ADHD (attention deficit hyperactivity disorder), positive psychology is primarily interested in how to improve the happiness of the ''average'' person. Martin Seligman, a psychologist at the University of Pennsylvania, USA, and a pioneer in the field of positive psychology, distinguishes different kinds and levels of happiness [4]. Hedonists who pursue immediate rewards such as the pleasure of buying something or receiving a compliment seek momentary happiness or what Seligman calls ''the pleasant life''. But these pleasures fade quickly and do not leave a lasting impact on subjective well-being. Enduring happiness, by contrast, is realized when we lead a meaningful life. After years spent studying what makes people happy, Seligman contends that it is rooted in attachment to something larger, and the larger the entity to which you attach yourself, the more meaning your life has [4].Eliminating all types of cancer would increase life expectancy in the USA by approximately only three yearsThis is clearly illustrated by the role of wealth. People often assume that being richer will mean being happier, yet surveys in many countries indicate that global levels of life satisfaction or happiness have not changed much during the past four decades despite large increases in real income per capita [5]. Most disposable income is spent on consumer goods that do little to actually enhance our well-being.In a recent study of the daily behaviour of happy people, researchers used an electronically activated recorder to record, and then later classify, participants'' daily conversations with others as either ''small talk'', that is banal conversations, and ''substantive talk'', where meaningful information was exchanged. They found that higher well-being was associated with less small talk and more substantive conversations [6]. While such a study does not establish the truth of Socrates'' famous claim that “the unexamined life is not worth living”, it does suggest that our need to feel attached to something larger is important to our happiness and well-being. This hypothesis is supported by recent studies on how people spend their money. Researchers from the University of British Columbia and Harvard Business School found that when individuals spend more money on prosocial goals, such as charity, they actually experience greater happiness than when they spend money on consumer products for themselves [7]. Similarly, the psychologist Barbara Fredrickson''s research on positive emotions—joy, serenity and gratitude—suggests that these expand cognition and behavioural tendencies [8].Finally, research on exemplars of resilience, that is, the ability of some people to cope and manage with tragic and traumatic events, could lead to the development of drugs that would increase people''s resilience. Avshalom Caspi and colleagues found that individuals with one or two copies of the short allele of the promoter of the 5-HTT serotonin receptor experience more depressive symptoms, diagnosable depression and suicidal thoughts in response to stressful events compared with individuals who are homozygous for the long allele [9].Cognitive functioning is another central topic of positive biology. What are the genetic and environmental determinants of high IQ, exceptional memory or social intelligence? Barbara Sahakian and colleagues found that the analeptic drug modafinil significantly enhanced performance tests of digit span, visual pattern recognition memory, spatial planning and stop-signal reaction time in healthy volunteers [10]. These findings of positive biology will eventually give us a better understanding of our human nature than the very limited focus on disease and pathology of negative biology and might then lead to new interventions, environments and attitudes that improve human well-being and happiness.Negative biology dominates medical research, from the questions research scientists tackle to the education of physicians and government regulation of health interventions. The dominance of this approach to the medical sciences presumes that the most important questions concern the causes of pathology rather than the causes of exemplar health and happiness. Positive biology takes a different approach: it does not limit the moral duty to apply knowledge and technology to improve human welfare to only treating specific diseases or impairments. Rather, it works under the assumption that if knowledge and research can improve people''s lives, there is a moral duty to advance that knowledge and promote well-being. Nor is positive biology predicated on a sharp distinction between therapy and enhancement. Instead, as the bioethicist John Harris has argued, “the overwhelming moral imperative for both therapy and enhancement is to prevent harm and confer benefit. Bathed in that moral light, it is unimportant whether the protection or benefit conferred is classified as enhancement or improvement, protection or therapy” [11].Generally, the medical system as a whole could be much more efficient if it concentrated its efforts on making people healthier and happier in the first place instead of its current focus on understanding and treating disease. Advancing the paradigm of positive biology should therefore help the medical sciences transcend the limited perspectives and aspirations of negative biology. Such a paradigm could help the world''s population to reap the benefits that new knowledge and technologies can offer in terms of making people healthier and happier. Societies and individuals already seek to achieve these goals: we educate our children to eat healthily and exercise and to develop their social goals to find fulfilment in life. The paradigm of positive biology simply encourages us to make use of the full range of options to realize these goals.…the medical system as a whole could be much more efficient if it concentrated its efforts on making people healthier and happier in the first place…In conclusion, positive biology is not contrary to the goals and aspirations of negative biology. Indeed the two paradigms are often complementary. For example, understanding why some high-risk individuals, such as sex workers, seem to have an intrinsic resistance to HIV-1 might spur the development of an HIV vaccine [12]. Similarly, understanding human brains with exceptional cognitive functioning might lead to new avenues for developing drugs and therapies against severe cognitive impairment. Understanding exemplars of health could create real benefits for those who are more vulnerable to disease and disability.     

The practitioner,the patient and resistance to change: recent ideas on compliance.

Despite the explosion of research into the effect of medical advice on patient behaviour, only about 50% of patients comply with long-term drug regimens. And when it comes to changes in lifestyle, the percentage of patients who comply with medical advice often falls to single figures. Review articles on compliance have traditionally concentrated on factors that make it easier for patients to adhere to medical advice. However, recent articles urge clinicians to be more understanding of the wider implications of compliance in their patients'' lives. This article focuses on how clinicians'' consulting methods can affect patients'' behaviour. Specifically, the authors consider the patient-centred clinical method as well as insights from and consulting techniques pioneered in the addictions field that can help to bring ambivalent patients closer to decisions about change. Instead of seeing resistance to change as rooted entirely in the patient, the authors view it as stemming partly from the way clinicians talk to patients. An advice-giving approach is usually inadequate to motivate people to embark on major lifestyle changes. Instead, the authors propose a negotiation-based framework that harnesses patients'' intrinsic motivation to make their own decisions. This approach also promotes clinicians'' acceptance of patients'' decisions, even if these decisions run counter to current medical wisdom.     

Health expectancy and the problem of substitute morbidity.

During the past century, the developed world has not only witnessed a dramatic increase in life expectancy (ageing), but also a concomitant rise in chronic disease and disability. Consequently, the tension between ''living longer'' on the one hand and health-related ''quality of life'' on the other has become an increasingly important health policy problem. The paper deals with two consequences of this so-called epidemiological transition in population health. The first one concerns the question of how--given the impressive changes--population health can be measured in an adequate and policy relevant present-day fashion. The second one is the so-called phenomenon of ''substitute morbidity and mortality'': more and more acute fatal diseases are replaced by non-fatal delayed degenerative diseases like dementia and arthritis. How the phenomenon of substitute morbidity and mortality affects the development of population health is illustrated with the epidemiological transitions, worldwide shifts in the main causes of death, assumptions used in models, adverse consequences of medical technologies and some results from intervention trials. Substitute morbidity and mortality may thwart our disease-specific expectations of interventions and asks for a shift to a ''total population health'' perspective when judging potential health gains of interventions. Better understanding of the dynamics that underly the changes in population health is necessary. Implications for data collections are more emphasis on morbidity data and their relation with mortality, more longitudinal studies, stricter requirements for intervention trials and more use of modelling as a tool. A final recommendation is the promotion of integrative measures of population health. For the latter several results are presented suggesting that, although the amount of morbidity and disability is growing with an increasing life expectancy, this is mild unhealthiness in particular. This finding supports the ''dynamic equilibrium'' theory. In absolute numbers, however, the burden of disease will continue to increase with further ageing of the population.     

Professional and popular views of chronic fatigue syndrome.

OBJECTIVE--To study the coverage of the chronic fatigue syndrome in the popular and professional press. DESIGN--Search of all original research papers on the chronic fatigue syndrome published in British journals from 1980 onwards and of professional trade papers, national newspapers, and women''s magazines. Interviews with six medical journalists. SETTING--British scientific, medical, and popular press. RESULTS--37 (49%) articles in research journals did not favour organic causes and 23 (31%) favoured organic causes. By contrast 31 (55%) articles in the medical trade press and 118 (69%) in national newspapers and women''s magazines favoured organic causes. CONCLUSIONS--Press coverage of chronic fatigue syndrome has amplified and distorted divisions in the research community concerning the chronic fatigue syndrome. Articles in the press concentrate on a simple medical model of illness reinforcing the stigma of psychological illness and dissatisfaction with traditional medical authority.     

Periodic health examination, 1999 update: 1. Detection,prevention and treatment of obesity

OBJECTIVES: (1) To evaluate the evidence relating to the effectiveness of methods to prevent and treat obesity, and (2) to provide recommendations for the prevention and treatment of obesity in adults aged 18 to 65 years and for the measurement of the body mass index (BMI) as part of a periodic health examination. OPTIONS: In adults with obesity (BMI greater than 27) management options include weight reduction, prevention of further weight gain or no intervention. OUTCOMES: The long-term (more than 2 years) effectiveness of (a) methods to prevent obesity and (b) methods to treat obesity. EVIDENCE: MEDLINE was searched for articles published from 1966 to April 1998 that related to the prevention and treatment of obesity; additional articles were identified from the bibliographies of review articles and the listings of Current Contents. Selection criteria were used to limit the analysis to prospective studies with at least 2 years'' follow-up. BENEFITS, HARM AND COSTS: Health benefits of weight reduction were evaluated in terms of alleviation of symptoms, improved management of obesity-related diseases and a reduction in major clinical outcomes. The health risk of weight-reduction methods were briefly evaluated in terms of increased mortality and morbidity. VALUES: The recommendations of this report reflect the commitment of the Canadian Task Force on Preventive Health Care to provide a structured, evidence-based appraisal of whether a manoeuvre should be part of a periodic health examination. RECOMMENDATIONS: (1) Prevention: There is insufficient evidence to recommend in favour of or against community-based obesity prevention programs; however, because of considerable health risks associated with obesity and the limited long-term effectiveness of weight-reduction methods, the prevention of obesity should be a high priority for health care providers (grade C recommendation). (2) Treatment: (a) For obese adults without obesity-related diseases, there is insufficient evidence to recommend in favour of or against weight-reduction therapy because of a lack of evidence supporting the long-term effectiveness of weight-reduction methods (grade C recommendation); (b) for obese adults with obesity-related diseases (e.g., diabetes mellitus, hypertension), weight reduction is recommended because it can alleviate symptoms and reduce drug therapy requirements, at least in the short term (grade B recommendation). (3) Detection: (a) for people without obesity-related diseases, there is insufficient evidence to recommend the inclusion or exclusion of BMI measurement as part of a periodic health examination, and therefore BMI measurement is left to the discretion of individual health care providers (grade C recommendation); (b) for people with obesity-related diseases, BMI measurement is recommended because weight reduction should be considered with a BMI of more than 27 (grade B recommendation). VALIDATION: The findings of this analysis were reviewed through an iterative process by the members of the Canadian Task Force on Preventive Health Care. SPONSORS: The Canadian Task Force on Preventive Health Care is funded through a partnership between the Provincial and Territorial Ministries of Health and Health Canada.