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Background Gestational diabetes mellitus (GDM) is an increasingly prevalent risk factor for type 2 diabetes. We evaluated the effectiveness of a group-based lifestyle modification program in mothers with prior GDM within their first postnatal year. Methods and Findings In this study, 573 women were randomised to either the intervention (n = 284) or usual care (n = 289). At baseline, 10% had impaired glucose tolerance and 2% impaired fasting glucose. The diabetes prevention intervention comprised one individual session, five group sessions, and two telephone sessions. Primary outcomes were changes in diabetes risk factors (weight, waist circumference, and fasting blood glucose), and secondary outcomes included achievement of lifestyle modification goals and changes in depression score and cardiovascular disease risk factors. The mean changes (intention-to-treat [ITT] analysis) over 12 mo were as follows: -0.23 kg body weight in intervention group (95% CI -0.89, 0.43) compared with +0.72 kg in usual care group (95% CI 0.09, 1.35) (change difference -0.95 kg, 95% CI -1.87, -0.04; group by treatment interaction p = 0.04); -2.24 cm waist measurement in intervention group (95% CI -3.01, -1.42) compared with -1.74 cm in usual care group (95% CI -2.52, -0.96) (change difference -0.50 cm, 95% CI -1.63, 0.63; group by treatment interaction p = 0.389); and +0.18 mmol/l fasting blood glucose in intervention group (95% CI 0.11, 0.24) compared with +0.22 mmol/l in usual care group (95% CI 0.16, 0.29) (change difference -0.05 mmol/l, 95% CI -0.14, 0.05; group by treatment interaction p = 0.331). Only 10% of women attended all sessions, 53% attended one individual and at least one group session, and 34% attended no sessions. Loss to follow-up was 27% and 21% for the intervention and control groups, respectively, primarily due to subsequent pregnancies. Study limitations include low exposure to the full intervention and glucose metabolism profiles being near normal at baseline. Conclusions Although a 1-kg weight difference has the potential to be significant for reducing diabetes risk, the level of engagement during the first postnatal year was low. Further research is needed to improve engagement, including participant involvement in study design; it is potentially more effective to implement annual diabetes screening until women develop prediabetes before offering an intervention. Trial Registration Australian New Zealand Clinical Trials Registry ACTRN12610000338066, Author(s): Sharleen L. O'Reilly 1,*, James A. Dunbar 2, Vincent Versace 3, Edward Janus 4,5, James D. Best 6, Rob Carter 2, Jeremy J. N. Oats 7, Timothy Skinner 8, [...]

The water retention and vasoconstriction observed in congestive heart failure (CHF) is attributed in part to arginine vasopressin (AVP). Water retention is modulated via the V2 receptor of AVP. The effects of chronic blocking of this receptor is investigated using the infarction-induced CHF model in rats. Results reveal that selective blocking of V2 leads to an increase in the excretion of water. The implications of these findings on diuretic therapy are discussed.

The diuretic effect of epidermal growth factor (EGF) in rats were analyzed and compared to the activity of the growth factor in sheep to determine the mechanisms involved in the activity of the 53-amino acid polypeptide. The presence of EGF in rats induced diuresis via a mechanism that was mediated by EGF-stimulated prostaglandin production which antagonized the hydrosmotic effect of arginine vasopressin. Furthermore, the diuretic action of EGF was significantly inhibited by indomethacin without affecting electrolyte excretion and plasma electrolyte levels.

Spontaneously hypertensive rats (SHR) were analyzed to determine the effects of short-term arginine vasopressin (AVP) receptor antagonists and angiotensin-converting enzyme (ACE) blockade on hypertension. Analysis of the developmental phase of hypertension in SHRs after the inhibition of V1A AVP receptors and ACE blockade indicated the presence of inhibited genetic expression of hypertension. The effects of V1A inhibition and ACE blockade indicated the role of AVP receptors and angiotensin II in the pathogenesis of genetic hypertension.

Studies of rats with diabetes mellitus establish a differential control of arginine varopressin (AVP) V1 and V2 receptors and second messenger system. While the downregulation of renal V2 receptors is not involved in production of polyuria in diabetic rats, the down regulation of V1 receptors and other functional changes cause altered biological responses to V1 receptor-mediated AVP.

The influence of the epidermal growth factor (EGF) on fluid balance electrolyte and hormone profiles is analyzed to characterize the role of EGF in enhancing urine volume and water intake in sheep. Fluid balance was not influenced by EGF treatment, although water intake and urine volume rose in a dose related manner. Polydipsia, polyuria and nitriuresis with neutral fluid balance were induced by the chronic intraneous infusion of 10-20 ug EGF/h into sheep. No conclusive proof has been obtanied regarding the major reaction of polymia or polydipsia to EGF.

Abstract Background Understanding how doctors think may inform both undergraduate and postgraduate medical education. Developing such an understanding requires valid and reliable measurement tools. We examined the measurement properties of the Inventory of Cognitive Bias in Medicine (ICBM), designed to tap this domain with specific reference to medicine, but with previously questionable measurement properties. Methods First year postgraduate entry medical students at Flinders University, and trainees (postgraduate doctors in any specialty) and consultants (N = 348) based at two teaching hospitals in Adelaide, Australia, completed the ICBM and a questionnaire measuring thinking styles (Rational Experiential Inventory). Results Questions with the lowest item-total correlation were deleted from the original 22 item ICBM, although the resultant 17 item scale only marginally improved internal consistency (Cronbach's α = 0.61 compared with 0.57). A factor analysis identified two scales, both achieving only α = 0.58. Construct validity was assessed by correlating Rational Experiential Inventory scores with the ICBM, with some positive correlations noted for students only, suggesting that those who are naïve to the knowledge base required to "successfully" respond to the ICBM may profit by a thinking style in tune with logical reasoning. Conclusion The ICBM failed to demonstrate adequate content validity, internal consistency and construct validity. It is unlikely that improvements can be achieved without considered attention to both the audience for which it is designed and its item content. The latter may need to involve both removal of some items deemed to measure multiple biases and the addition of new items in the attempt to survey the range of biases that may compromise medical decision making.

Abstract Background How humans think and make decisions is important in understanding behaviour. Hence an understanding of cognitive processes among physicians may inform our understanding of behaviour in relation to evidence implementation strategies. A personality theory, Cognitive-Experiential Self Theory (CEST) proposes a relationship between different ways of thinking and behaviour, and articulates pathways for behaviour change. However prior to the empirical testing of interventions based on CEST, it is first necessary to demonstrate its suitability among a sample of healthcare workers. Objectives To investigate the relationship between thinking styles and the knowledge and clinical practices of doctors directly involved in the management of acute coronary syndromes. Methods Self-reported doctors' thinking styles (N = 74) were correlated with results from a survey investigating knowledge, attitudes, and clinical practice, and evaluated against recently published acute coronary syndrome clinical guidelines. Results Guideline-discordant practice was associated with an experiential style of thinking. Conversely, guideline-concordant practice was associated with a higher preference for a rational style of reasoning. Conclusion Findings support that while guidelines might be necessary to communicate evidence, other strategies may be necessary to target discordant behaviours. Further research designed to examine the relationships found in the current study is required.

Abstract Background Falls in hospital are frequent and their consequences place an increased burden on health services. We evaluated a falls prevention strategy consisting of the introduction of volunteers to 'sit' with patients identified as being at high risk of falling. Methods Two four bed 'safety bays' located on medical wards in two hospitals within southern Adelaide were used. Ward fall rates (expressed as falls per 1000 occupied bed days) were compared in the baseline period (February-May 2002) with the implementation period (February – May 2003) using incident rate ratios and 95% confidence intervals. The number of hours of volunteered time was also collected. Results No patient falls occurred on either site when volunteers were present. However, there was no significant impact on overall ward fall rates. In the baseline period, there were 70 falls in 4828 OBDs (14.5 falls per 1000 OBDs). During the implementation period, there were 82 falls in 5300 OBDs (15.5 falls per 1000 OBD). The IRR for falls in the implementation versus baseline period was 1.07 (95%CI 0.77 – 1.49; P = 0.346). Volunteers carried out care activities (e.g. cutting up food), provided company, and on occasions advocated on behalf of the patients. Volunteers donated 2345 hours, at an estimated value to the hospitals of almost $57,000. Conclusion Volunteers may play an important and cost-effective role in enhancing health care and can prevent falls in older hospital patients when they are present. Full implementation of this program would require the recruitment of adequate numbers of volunteers willing to sit with all patients considered at risk of falling in hospital. The challenge for future work in this area remains the sustainability of falls prevention strategies.

Abstract Background A better theoretical base for understanding professional behaviour change is needed to support evidence-based changes in medical practice. Traditionally strategies to encourage changes in clinical practices have been guided empirically, without explicit consideration of underlying theoretical rationales for such strategies. This paper considers a theoretical framework for reasoning from within psychology for identifying individual differences in cognitive processing between doctors that could moderate the decision to incorporate new evidence into their clinical decision-making. Discussion Parallel dual processing models of reasoning posit two cognitive modes of information processing that are in constant operation as humans reason. One mode has been described as experiential, fast and heuristic; the other as rational, conscious and rule based. Within such models, the uptake of new research evidence can be represented by the latter mode; it is reflective, explicit and intentional. On the other hand, well practiced clinical judgments can be positioned in the experiential mode, being automatic, reflexive and swift. Research suggests that individual differences between people in both cognitive capacity (e.g., intelligence) and cognitive processing (e.g., thinking styles) influence how both reasoning modes interact. This being so, it is proposed that these same differences between doctors may moderate the uptake of new research evidence. Such dispositional characteristics have largely been ignored in research investigating effective strategies in implementing research evidence. Whilst medical decision-making occurs in a complex social environment with multiple influences and decision makers, it remains true that an individual doctor's judgment still retains a key position in terms of diagnostic and treatment decisions for individual patients. This paper argues therefore, that individual differences between doctors in terms of reasoning are important considerations in any discussion relating to changing clinical practice. Summary It is imperative that change strategies in healthcare consider relevant theoretical frameworks from other disciplines such as psychology. Generic dual processing models of reasoning are proposed as potentially useful in identifying factors within doctors that may moderate their individual uptake of evidence into clinical decision-making. Such factors can then inform strategies to change practice.