The etiology of stammering and methods for its treatment /

Caption title.

The etiology of subacute bacterial endocarditis: a historical résumé.

Bibliography: leaves 27-30.

Micro-organisms with special reference to the etiology of the infective diseases,

Literature: p. 1-63.

Exploring the Etiology of the Association Between Birthweight and IQ in an Adolescent Twin Sample

The negative effects of very low birthweight on intellectual development have been well documented, and more recently this effect has been shown to generalise to birthweights within the normal range. In this study we investigate the etiology of this relationship by using a classical twin design to disentangle the contributions of genes and environment. A previous Dutch study (Boomsma et al., 2001) examining these effects indicated that genes were important in mediating the association of birthweight to full IQ measured at ages 7 and 10, but not at ages 5 and 12. Here the association between birthweight and IQ at age 16 is considered (N = 523 twin pairs). Using variance components modeling we found that the genetic variance in birthweight (4%) completely overlapped with that in verbal IQ but not performance or full IQ. Results further showed the importance of shared environmental effects on birthweight (similar to 60%) but not on IQ (with genes explaining up to 72% of IQ variance). Models incorporating a direction of causation parameter between birthweight and IQ provided adequate fit to the data in either causal direction for performance and full IQ, but the model with verbal 10 causing birthweight was preferred to one in which birthweight influenced verbal IQ. As the measurement of birthweight precedes the measurement of twins' IQ at age 16, the influence of verbal IQ might be better considered as a proxy for parents' 10 or education, and it is possible that brighter mothers provide better prenatal environments for their children.

The etiology of social phobia: Empirical evidence and an initial model

Research into the etiology of social phobia has lagged far behind that of descriptive and maintaining factors. The current paper reviews data from a variety of sources that have some bearing on questions of the origins of social fears. Areas examined include genetic factors, temperament, childrearing, negative life events, and adverse social experiences. Epidemiological data are examined in detail and factors associated with social phobia such as cognitive distortions and social skills are also covered. The paper concludes with an initial model that draws together some of the current findings and aims to provide a platform for future research directions. (C) 2004 Elsevier Ltd. All rights reserved.

Frequency of insomnia report in patients with obstructive sleep apnoea hypopnea syndrome (OSAHS)

Background and purpose: Insomnia and Obstructive Sleep Apnoea Hypopnea Syndrome (OSAHS) are the two most common sleep disorders, and both have significant associated health costs. Despite this, relatively little is known about the prevalence or impact of insomnia in those with OSAHS, although a recent study suggested there may be substantial comorbidity between these disorders [Chest 120 (2001) 1923-9]. The primary aim of this study was to further explore the prevalence of insomnia in OSAHS. A secondary aim was to assess the effect of factors that may impact on both conditions, including mood and sleep-beliefs. Patients and methods: Consecutive patients referred to an accredited Sleep Investigations Unit (n = 105) completed a brief standardized battery of validated questionnaires assessing sleep-related variables and mood. Results: Results showed a high rate of prevalence of clinical insomnia in this OSAHS population, and a strong positive correlation between OSAHS and insomnia symptom severity. Further, OSAHS patients with comorbid insomnia had increased levels of depression, anxiety and stress compared to patients with OSAHS-only, and both patient groups reported similar and significant levels of dysfunctional beliefs about sleep. Findings in relation to habitual sleep, assessed using subjective (diary) and objective criteria (polysomnogram), were mixed but generally showed greater sleep disturbance among those with OSAHS-insomnia compared to those with OSAHS-only. Conclusions: Overall these findings suggest that comorbidity of insomnia in OSAHS patients may lead to increased OSAHS severity and that patients with both conditions may experience more symptoms relating to depression, anxiety and stress. These findings underscore the need for insomnia assessment and management services, even in clinics that primarily service patients with OSAHS. (C) 2004 Elsevier B.V. All rights reserved.

The experience of insomnia among older women

Study Objectives: To measure sleeping difficulty and sleep quality among older women, explore experience and attitudes towards sleep, and test for negative association between difficulty sleeping and health-related quality of life. Design: Four-year longitudinal study. Setting: Women were participants in the Australian Longitudinal Study on Women's Health. Participants: Women were sampled according to use of sleeping medication and classified into 4 groups: sleeping badly and using sleeping medications; not sleeping badly, but using sleeping medications; sleeping badly, not using sleeping medications; not sleeping badly, not using sleeping medications. Interventions: None. Measurements and Results: Sleeping difficulty and sleeping-medication use were measured at Survey 1, Survey 2 (3 years later), and Survey 3 (4 years later). Survey 3 included: Nottingham Health Profile Sleep Subscale, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Geriatric Depression Scale, Duke Social Support Index, Medical Outcomes Study Short-Form 36-item Health Survey, and a 21-item life events scale. Survey 3 was returned by 1011 women (84%). Sleeping problems were negatively associated with SF-36 subscale scores. Most associations remained significant after comorbid conditions, Geriatric Depression Scale, life events scores, and medication use were added to models. Most women with sleeping problems (72%) sought help from a doctor, and 54% used prescribed sleeping medications in the past month. Conclusions: Sleeping difficulty is a serious symptom for older women and is associated with poorer quality of life. Some of this effect can be explained by comorbidities, depression scores, life events, and use of sleeping medications.

Safety behaviors and dysfunctional beliefs about sleep: Testing a cognitive model of the maintenance of insomnia

Objective: Our aim was to determine if insomnia severity, dysfunctional beliefs about sleep, and depression predicted sleep-related safety behaviors. Method: Standard sleep-related measures (such as the Insomnia Severity Index; the Dysfunctional Beliefs About Sleep scale; the Depression, Anxiety, and Stress Scale; and the Sleep-Related Behaviors Questionnaire) were administered. Additionally, 14 days of sleep diary (Pittsburg Sleep Diary) data and actual use of sleep-related behaviors were collected. Results: Regression analysis revealed that dysfunctional beliefs about sleep predicted sleep-related safety behaviors. Insomnia severity did not predict sleep-related safety behaviors. Depression accounted for the greatest amount of unique variance in the prediction of safety behaviors, followed by dysfunctional beliefs. Exploratory analysis revealed that participants with higher levels of depression used more sleep-related behaviors and reported greater dysfunctional beliefs about their sleep. Conclusion: The findings underlie the significant influence that dysfunctional beliefs have on individuals' behaviors. Moreover, the results suggest that depression may need to be considered as an explicit component of cognitive-behavioral models of insomnia. (c) 2006 Elsevier Inc. All rights reserved.

Medicalisation and beyond: the social construction of insomnia and snoring in the news

What role do the media play in the medicalization of sleep problems? This article, based on a British Academy funded project, uses qualitative textual analysis to examine representations of insomnia and snoring in a large representative sample of newspaper articles taken from the UK national press from the mid-1980s to the present day. Constructed as ‘common problems’ in the population at large, insomnia and snoring we show are differentially located in terms of medicalizing—healthicizing discourses and debates. Our findings also suggest important differences in the gendered construction of these problems and in terms of tabloid and ‘broadsheet’ newspaper coverage of these issues. Newspaper constructions of sleep, it is concluded, are complex, depending on both the ‘problem’ and the paper in question.

New insights into the etiology of preeclampsia:identification of key elusive factors for the vascular complications

The incidence of preeclampsia is reduced by a third in smokers, but not in snuff users. Soluble Flt-1 (sFlt-1) and soluble endoglin (sEng) are increased prior to the clinical onset of preeclampsia. Animals exposed to high circulating levels of sFlt-1 and sEng elicit severe preeclampsia-like symptoms. Smokers have reduced circulating sFlt-1 and cigarette smoke extract decreases sFlt-1 release from placental villous explants. An anti-inflammatory enzyme, heme oxygenase-1 (HO-1) and its metabolite carbon monoxide (CO), inhibit sFlt-1 and sEng release. Women with preeclampsia exhale less CO than women with normal pregnancies and HO expression decreases as the severity of preeclampsia increases. In contrast, sFlt-1 levels increase with increasing severity. More importantly, chorionic villous sampling from women at eleven weeks gestation shows that HO-1 mRNA expression is decreased in women who go on to develop preeclampsia. Collectively, these facts provide compelling evidence to support the proposition that the pathogenesis of preeclampsia is largely due to loss of HO activity. This results in an increase in inflammation and excessive elevation of the two key anti-angiogenic factors responsible for the clinical signs of preeclampsia. These findings provide strong evidence for a protective role of HO-1 in pregnancy and identify HO as a target for the treatment of preeclampsia. The cardiovascular drugs, statins, stimulate HO-1 expression and inhibit sFlt-1 release in vivo and in vitro, thus, they have the potential to ameliorate early onset preeclampsia. The StAmP trial is underway to address this and if positive, its outcome will lead to the very first therapeutic intervention to prolong affected pregnancies.

On the etiology of cardiovascular diseases: a new framework for understanding literature results

The interpretative framework presented here provides a rationale for many well-known features of cardiovascular diseases. Prolonged acidemia with high blood levels of free fatty acids is proposed to shape the basic context for formation of fatty acid micelles and vesicles with an acidic core that fuse with the endothelia, disrupt vital cell processes, and initiate atherosclerotic plaque formation. It offers an explanation for the distributed localization of atherosclerotic lesions, and how mild cases of occurrence of fatty acids vesicles formed within the heart and the arteries close to the heart may cause such lesions. It provides a rationale for how acute events, namely heart attacks and strokes, may arise from stormy development of fatty acid vesicles within the heart. Additionally, a process is proposed for clot development from the existing fatty acid vesicles.

Information processing in sleep-onset insomnia : a test of the neurocognitive model /

The present thesis study is a systematic investigation of information processing at sleep onset, using auditory event-related potentials (ERPs) as a test of the neurocognitive model of insomnia. Insomnia is an extremely prevalent disorder in society resulting in problems with daytime functioning (e.g., memory, concentration, job performance, mood, job and driving safety). Various models have been put forth in an effort to better understand the etiology and pathophysiology of this disorder. One of the newer models, the neurocognitive model of insomnia, suggests that chronic insomnia occurs through conditioned central nervous system arousal. This arousal is reflected through increased information processing which may interfere with sleep initiation or maintenance. The present thesis employed event-related potentials as a direct method to test information processing during the sleep-onset period. Thirteen poor sleepers with sleep-onset insomnia and 1 2 good sleepers participated in the present study. All poor sleepers met the diagnostic criteria for psychophysiological insomnia and had a complaint of problems with sleep initiation. All good sleepers reported no trouble sleeping and no excessive daytime sleepiness. Good and poor sleepers spent two nights at the Brock University Sleep Research Laboratory. The first night was used to screen for sleep disorders; the second night was used to investigate information processing during the sleep-onset period. Both groups underwent a repeated sleep-onsets task during which an auditory oddball paradigm was delivered. Participants signalled detection of a higher pitch target tone with a button press as they fell asleep. In addition, waking alert ERPs were recorded 1 hour before and after sleep on both Nights 1 and 2.As predicted by the neurocognitive model of insomnia, increased CNS activity was found in the poor sleepers; this was reflected by their smaller amplitude P2 component seen during wake of the sleep-onset period. Unlike the P2 component, the Nl, N350, and P300 did not vary between the groups. The smaller P2 seen in our poor sleepers indicates that they have a deficit in the sleep initiation processes. Specifically, poor sleepers do not disengage their attention from the outside environment to the same extent as good sleepers during the sleep-onset period. The lack of findings for the N350 suggest that this sleep component may be intact in those with insomnia and that it is the waking components (i.e., Nl, P2) that may be leading to the deficit in sleep initiation. Further, it may be that the mechanism responsible for the disruption of sleep initiation in the poor sleepers is most reflected by the P2 component. Future research investigating ERPs in insomnia should focus on the identification of the components most sensitive to sleep disruption. As well, methods should be developed in order to more clearly identify the various types of insomnia populations in research contexts (e.g., psychophysiological vs. sleep-state misperception) and the various individual (personality characteristics, motivation) and environmental factors (arousal-related variables) that influence particular ERP components. Insomnia has serious consequences for health, safety, and daytime functioning, thus research efforts should continue in order to help alleviate this highly prevalent condition.

Management of over-the-counter insomnia complaints in Australian community pharmacies: A standardized patient study

Objective To evaluate the current management of over-the-counter (OTC) insomnia complaints in Australian community pharmacies using standardized patient methodology. Methods Trained standardized patients visited a sample of 100 randomly selected South East Queensland community pharmacies in June 2011. The standardized patients enacted two OTC insomnia scenarios: a direct product request (DPR) (n = 50) and a symptom-based request (SBR) (n = 50). Results of the interactions were documented immediately after each visit and evaluated using the Pharmaceutical Society of Australia's WHAT STOP GO protocol as a standard comparison. Key findings Of all DPRs, 30% were handled entirely by the pharmacist, 70% of staff enquired about specific symptoms and 28% investigated the cause of insomnia. No staff investigated the frequency of product use. The DPR scenario resulted in a 92% supply of the requested doxylamine product (Restavit). In the SBR scenario, 18% of requests were handled entirely by the pharmacist, 58% of staff enquired about specific symptoms and 44% investigated the cause of insomnia. Staff recommended medicated products (38%), or herbal (78%) or non-drug techniques (18%). Investigation into smoking and alcohol intake was not undertaken in DPR or SBR interactions, while questioning on caffeine intake was undertaken in 2 and 14% of cases respectively. There were no significant differences found in the handling of sleep requests by pharmacists compared to pharmacy assistants. Conclusion The standardized patient methodology was a successful way to assess the community pharmacy counselling provided with OTC sleep requests and suboptimal staff responses were found when compared with recommended practice standards.

The impact of relaxing music on insomnia-related thoughts and behaviours

Insomnia is a pervasive problem involving poor sleep quality and quantity. Previous research has suggested that music listening can help alleviate insomnia, but exactly how music helps sleep problems has not been determined. A greater understanding of these processes could help practitioners to design more effective music-based insomnia treatments. This randomised controlled trial was designed to assess the influences of nightly music listening on the sleep-related thoughts and behaviours described in Harvey’s (2002) cognitive model of insomnia maintenance. University students, including a range of good and poor sleepers, were randomly assigned to a music listening group or a control group and were assessed before and after a two-week music listening intervention. Measures included a range of self-report scales, each assessing an element of Harvey’s cognitive model. During the intervention, the music listening group was asked to listen to provided music for at least 20 minutes each night. The control group was asked to maintain their regular nightly routines. Results indicated that the music listening group significantly improved on most of the factors theorised to influence sleep quality, although their actual sleep quality did not significantly improve. The control group did not change significantly on any measures. The results of this study suggest that music listening can have positive impacts on a range of factors theorised to influence sleep quality. However, as the music was not shown to actually improve sleep quality, Harvey’s cognitive model explanation of music’s effect on sleep quality may require further investigation.