Stability and change. Glycemic control and lifestyle support in type 2 diabetes.

Type 2 diabetes is a serious, lifestyle-related condition characterized by insufficient glycemic control resulting in hyperglycemia. Long-term hyperglycemia is a major risk factor for a range of health complications, and type 2 diabetes complications are among the leading causes of morbidity and mortality worldwide. Of all forms of diabetes, type 2 diabetes constitutes around 90% of cases, indicating its impact on both an individual and a societal level. The management of type 2 diabetes is an everyday task, and the main responsibility for healthy glycemic control lies with the individual. Most individuals with type 2 diabetes, however, do not meet recommended treatment targets, implying a need for a better understanding of factors related to glycemic control, as well as for new, cost-effective solutions to support those with the disease. The overall aim of this thesis was to examine patient factors associated with glycemic control, and to develop and evaluate a web-based intervention to support diabetes self-management. Two prospective cohort studies (studies I and II) were conducted to examine the associations between sociodemographic and psychological factors, and glycemic control. A qualitative study utilizing semi-structured interviews (study III) was conducted to explore patients’ needs and expectations regarding support for diabetes self-management, and views on the development of an intervention to support diabetes management. The effect of a new, web-based lifestyle tool for glycemic control in individuals with type 2 diabetes was investigated through a randomized controlled trial (study IV). The effect of the tool was further examined in a subgroup of insulin- resistant and obese individuals, and the cost-effectiveness of the tool was estimated. Results showed that men, individuals with obesity, and participants who reported a more negative appraisal of diabetes, had less stable glycemic control compared to other groups. Patients reported physical and emotional barriers to appropriate diabetes management, as well as a disconnect between their way of life and the lifestyle advice they received from health care professionals, and described a need for accessible and reliable support for diabetes self-management. Based on these results, a web-based lifestyle tool was developed and evaluated. Improved glycemic control was found in participants using the tool, compared to a waitlist control group. The response was further pronounced in a subgroup of insulin-resistant and obese individuals, and the tool was estimated to be cost-effective based on its potential ability to control risk factors for the disease. Men, individuals with obesity, and individuals with a more negative experience of type 2 diabetes may be at greater risk of developing future diabetes complications due to their attenuated glycemic variability. There is a need for personalized and autonomy-supportive interventions that can provide both encouragement and relevant information to the patient group, to support risk factor control. A new, web-based intervention supporting self- reflection and including a personal adaptation of health information can be used to support enhanced glycemic control in individuals with type 2 diabetes, and may be particularly effective in obese and insulin-resistant individuals.