Stability of diagnosis, symptoms and functioning across the life span is central to understanding any disorder and yet remains a relatively unexplored area in the study of autism (Sigman & McGovern, 2005). This is particularly apparent in the development of communication, including social interaction and language development in children with autism spectrum disorder (ASD), as there is little research on longitudinal development of children with ASD in general. The outlook on ASD has changed throughout the years, and although the emphasis on speech delay and communication problems have been separated from ASD, it is still one of the most common causes of initial referral in autism diagnoses (Pickles, Risi & Lord, 2004). Understanding the trajectory of communication for a child with ASD is fundamental in providing support and intervention in early years development. As communication is also a primary indicator on later development, it can gage outcomes into adaptive skills, school achievement and adult independence in later adult life. Eleven articles were identified in order to systematically review longitudinal studies based on communication development in ASD, or lack thereof, and why it is important to further carry out research in this area. This review seeks to explore: 1. How the development of different communicative functions in children with ASD is related to change over time. And, 2. What aspects of the child’s proximal processes and/or the child’s characteristics are discussed during measurement periods. Communicative functions were the most common form of communication observed in the studies at assessment periods and as for time points; two assessment periods were most common showing a linear trajectory of progress or decline from time point 1 and 2. All studies discussed aspects of child characteristics, most predominantly being gender and I.Q., however lacked insight into the significance of these and factors of proximal process during measurement periods in the studies reviewed. Ultimately, results display a need for more studies with at least three time points. With two time points only comes a “before” and “after” perspective, whereas, three or more time points enables collection of waves of data, showing key predictors of change in communication in children with a form of ASD.

Type 2 diabetes mellitus (T2DM) is a global health concern affecting six to ten percent of adults worldwide, with the number of diagnosed individuals projected to double in the next 25 years. However, effective public health strategies can help mitigate its impact on quality of life, morbidity, mortality and the associated social and economic burden. In Sweden, screening programs classify individuals with Impaired fasting glucose (IFG) as high-risk individuals, however scholars argue that preventative measures should also include those at lower fasting plasma glucose (FPG) concentrations as some evidence suggests that the disease begins developing several years before the current threshold. A systematic review and meta-analysis of cohort and case-control studies was conducted with the purpose of exploring the IFG threshold from a longitudinal perspective. Eleven studies on the incidence rates of T2DM in normoglycemic individuals and seven studies on pre-diagnostic trajectories of FPG concentrations were analyzed. Incidence rates increased progressively across the normoglycemic range, with a twelve-fold difference between the low and high end. FPG concentrations in eventual progressors and non-diabetic controls were significantly different twelve years prior to diagnosis. Mildly increasing FPG concentrations were observed in eventual progressors until three years before diagnosis, at which a larger increase followed. In the last year before diagnosis, FPG concentrations rose dramatically in this group. The findings imply that a lowering of the threshold would extend the time spent in the IFG state, allowing for earlier identification of at-risk individuals. In addition, further stratification of normoglycemic range may enhance the accuracy of T2DM risk assessment.

Background Type 2 diabetes mellitus (T2DM) is a globally prevalent disease anticipated to double from 500 million diagnosed cases in 2021 to more than one billion by 2050. The investigation of the potentially protective effects of skeletal muscle mass on glucose intolerance may lead to the development of more precise screening protocols. Purpose This thesis aimed to address the lack of clear consensus in existing literature by exploring the relationship between skeletal muscle mass and glucose intolerance. Methods Fifteen healthy young adults were recruited to partake in a prospective correlational study. The participants underwent anthropometric measurements and an oral glucose tolerance test (OGTT). Anthropometric data was collected using an bioelectrical impedance analysis (BIA) scale. Blood glucose levels were measured using capillary sampling before and after ingestion of a 75 g/200 mL glucose solution. Statistical analysis included Spearman’s rank correlation test and Pearson’s correlation coefficient test. Results All associations between skeletal muscle mass and glucose intolerance were of moderate strength. Skeletal muscle mass (SMM) correlated significantly with glucose concentrations two hours (2hPG) following ingestion of the glucose solution and an adjusted measure of SMM was significantly associated with glucose area under the curve (AUC). Statistical significance was also found between Sex and incremental glucose area under the curve (iAUC). Conclusion This thesis suggests an inverse relationship between skeletal muscle mass and glucose intolerance in a group of healthy young adults. The results imply the potential usefulness of incorporating muscle mass when determining the glucose load during an OGTT, especially in preventive contexts. Nevertheless, further research with larger samples is crucial to establish precise cutoff levels for clinical applications. / Bakgrund Typ 2 diabetes mellitus (T2DM) är en global sjukdom och antalet diagnostiserade individer förväntas fördubblas från 500 miljoner fall 2021 till över en miljard år 2050. En undersökning av muskelmassans potentiellt skyddande effekt på glukostolerans kan leda till utvecklandet av noggrannare screeningmetoder. Syfte Syftet med denna uppsats var att bemöta den bristfälliga konsensus som råder bland befintlig forskning genom att undersöka sambandet mellan muskelmassa och glukosintolerans. Metod Femton friska yngre vuxna rekryterades för att delta i en prospektiv korrelationsstudie. Deltagarna genomgick antropometriska mätningar samt ett oralt glukostoleranstest (OGTT). Antropometriska värden mättes med hjälp av en bioelektrisk impedansanalysvåg. Blodglukosnivåer mättes kapillärt före och efter intag av en 75 g/200 mL glukoslösning. Statistisk analys inkluderade Spearmans rangkorrelationstest och Pearsons korrelationskoefficientstest. Resultat Alla samband mellan muskelmassa och glukosintolerans var av måttlig styrka. Muskelmassa (SMM) korrelerade signifikant med blodglukos två timmar (2hPG) efter intag av glukoslösningen och ett justerat SMM-mått (adjSMM) var signifikant associerat med arean under glukoskurvan (AUC). Statistisk signifikans hittades även mellan kön och den inkrementella arean under glukoskurvan (iAUC). Slutsats Resultaten från denna uppsats antyder att ett omvänt samband existerar mellan muskelmassa och glukosintolerans hos en grupp friska yngre vuxna. Resultatet innebär en potentiell möjlighet att använda muskelmassan vid bestämmandet av mängden glukos som administreras vid ett OGTT, särskilt i preventiva syften. Ytterligare forskning med fler studiedeltagare är avgörande för att fastställa exakta gränsvärden för klinisk tillämpning.