BackgroundExperience-based codesign (EBCD) is an approach to health service design that engages patients and healthcare staff in partnership to develop and improve health services or pathways of care. The aim of this systematic review was to examine the use (structure, process and outcomes) and reporting of EBCD in health service improvement activities.MethodsElectronic databases (MEDLINE, CINAHL, PsycINFO and The Cochrane Library) were searched to identify peer-reviewed articles published from database inception to August 2018. Search terms identified peer-reviewed English language qualitative, quantitative and mixed methods studies that underwent independent screening by two authors. Full texts were independently reviewed by two reviewers and data were independently extracted by one reviewer before being checked by a second reviewer. Adherence to the 10 activities embedded within the eight-stage EBCD framework was calculated for each study.ResultsWe identified 20 studies predominantly from the UK and in acute mental health or cancer services. EBCD fidelity ranged from 40% to 100% with only three studies satisfying 100% fidelity.ConclusionEBCD is used predominantly for quality improvement, but has potential to be used for intervention design projects. There is variation in the use of EBCD, with many studies eliminating or modifying some EBCD stages. Moreover, there is no consistency in reporting. In order to evaluate the effect of modifying EBCD or levels of EBCD fidelity, the outcomes of each EBCD phase (ie, touchpoints and improvement activities) should be reported in a consistent manner.Trial registration numberCRD42018105879.

Prader-Willi syndrome (PWS) is the predominant genetic cause of obesity in humans. Recent clinical reports have suggested that micro-deletion of the Snord116 gene cluster can lead to PWS, however, the extent of the contributions of the encoded snoRNAs is unknown. Here we show that mice lacking Snord116 globally have low birth weight, increased body weight gain, energy expenditure and hyperphagia. Consistent with this, microarray analysis of hypothalamic gene expression revealed a significant alteration in feeding related pathways that was also confirmed by in situ hybridisation. Importantly, selective deletion of Snord116 only from NPY expressing neurons mimics almost exactly the global deletion phenotype including the persistent low birth weight, increased body weight gain in early adulthood, increased energy expenditure and hyperphagia. Mechanistically, the lack of Snord116 in NPY neurons leads to the upregulation of NPY mRNA consistent with the hyperphagic phenotype and suggests a critical role of Snord116 in the control of NPY neuronal functions that might be dysregulated in PWS.

Our pilot study demonstrates that exenatide is well tolerated in PWS patients. It increases satiety independently of measured appetite hormones, exerting glucose lowering, and insulinotropic effects similarly in PWS and OBESE patients. Larger prospective studies should investigate whether chronic exenatide administration will reduce hyperphagia and overweight in PWS patients without side effects.

ObjectivePrader-Willi syndrome (PWS) is a leading genetic cause of obesity, characterized by hyperphagia, endocrine and developmental disorders. It is suggested that the intense hyperphagia could stem, in part, from impaired gut hormone signaling. Previous studies produced conflicting results, being confounded by differences in body composition between PWS and control subjects. Design Fasting and postprandial gut hormone responses were investigated in a cross-sectional cohort study including 10 adult PWS, 12 obese subjects matched for percentage body fat and central abdominal fat, and 10 healthy normal weight subjects. Methods PYY [total], PYY , GLP-1[active] and ghrelin [total] were measured by ELISA or radioimmunoassay. Body composition was assessed by dual energy X-ray absorptiometry. Visual analog scales were used to assess hunger and satiety. Results In contrast to lean subjects (p < 0.05), PWS and obese subjects were similarly insulin resistant and had similar insulin levels. Ghrelin[total] levels were significantly higher in PWS compared to obese subjects before and during the meal (p < 0.05). PYY meal responses were higher in PWS than in lean subjects (p = 0.01), but not significantly different to obese (p = 0.08), with an additional non-significant trend in PYY[total] levels. There were no significant differences in self-reported satiety between groups, however PWS subjects reported more hunger throughout (p = 0.003), and exhibited a markedly reduced mealinduced suppression of hunger (p = 0.01) compared to lean or obese subjects. Conclusions Compared to adiposity-matched control subjects, hyperphagia in PWS is not related to a lower postprandial GLP-1 or PYY response. Elevated ghrelin levels in PWS are consistent with increased hunger and are unrelated to insulin levels.