Youth with type 1 diabetes: A study of their epidemiological and clinical characteristics, glycaemic control and psychosocial predictors, and an evaluation of the efficacy of Motivational Interviewing in improving diabetes management

Poorly controlled diabetes is common among the majority of youth with type 1 diabetes and can lead to adverse health outcomes at an early age. There is a need to change this to minimise the risk of negative long-term consequences. The onset of complications from diabetes can be prevented or delayed with good management as demonstrated by blood glucose being kept close to or within the normal range. Diabetes control is challenging for young people due to a combination of physiological and psychological factors. Diabetes control needs to be monitored both at an individual level and also at a population level, in order to optimise health outcomes and provide important information for health service provision. There are gaps in knowledge relating to the current level of diabetes control at a population level and of the epidemiological characteristics of youth with type 1 diabetes in the Canterbury region in New Zealand. There has been no research of this nature in the Canterbury region since 2003. There are also gaps in knowledge and a lack of national and international research that investigates psychosocial characteristics of youth with type 1 diabetes and the impact these may have on diabetes control. There is a potentially promising intervention, namely, Motivational Interviewing (MI), that although previous research investigating it with diabetes has shown some promise, methodological problems have limited the conclusions that can be drawn. This thesis, within the New Zealand context, addresses some of these gaps and adds to the body of knowledge of research concerning diabetes control and youth with type 1 diabetes, and investigates MI intervention for youth with poorly controlled diabetes. The thesis encompasses three studies. The first study is an audit that provides up-to-date information on epidemiological characteristics and clinical outcomes for the youth population with type 1 diabetes residing in the Canterbury region. The second study is a cross-sectional study that investigates the relationship between glycaemic control and key psychosocial characteristics: illness beliefs, self-efficacy, and quality of life in youth with type 1 diabetes in Canterbury. The third study is a longitudinal study that investigates the efficacy of MI as an intervention for youth with poorly controlled type 1 diabetes, and explores its impact on diabetes outcomes using statistical and clinical analyses. The first study showed that from 2003 to 2010 the prevalence of adolescents and young adults with type 1 diabetes in Canterbury has increased; there is therefore an increased demand on health resources. In addition, in 2010 glycaemic control at a population level was in the poorly controlled diabetes range and this had remained unchanged since 2003. This suggests the need for more intensive interventions. The second study found that poor diabetes control in youth with type 1 diabetes is influenced by a number of factors, including negative views on diabetes, lower perceived personal control, higher diabetes-related concerns, and lower levels of worry about complications. These findings provide a new understanding of the importance of balancing worries about diabetes complications and the perception of diabetes as a threatening condition. The third study showed that the MI intervention was generally successful in improving diabetes outcomes – clinical, psychosocial, and behavioural changes were observed. Statistically and clinically significant positive changes were found across multiple variables: glycated haemoglobin (HbA1c), glycaemic variability, adherence, and psychosocial functioning. Taken together, the findings of the three studies indicate that majority of youth with type 1 diabetes in the Canterbury region had poor glycaemic control, which suggests that additional interventions may be required to improve management of their condition, especially interventions targeting psychosocial functioning (e.g., illness perceptions) and diabetes self-management. Motivational Interviewing may be a viable option, and therefore further research into this approach is recommended