Multimorbidity in People with Type 2 Diabetes: Exploration of Associations with Mortality and Glycaemia
AuthorChiang, Jason I-Hsiu
Document TypePhD thesis
Access StatusThis item is embargoed and will be available on 2022-08-24. This item is currently available to University of Melbourne staff and students only, login required.
© 2020 Jason I-Hsiu Chiang
Background Type 2 diabetes is a leading health priority of the 21st century. Type 2 diabetes management is complex for both practitioners and patients, made more so because diabetes rarely occurs on its own. Indeed, multimorbidity (the co-occurrence of two or more chronic conditions in an individual) is the norm in diabetes. Multimorbidity, brings about many challenges including difficulties in managing the competing demands of multiple conditions. This can result in reduced adherence to complicated therapeutic regimens. This in turn could lead to suboptimal glycaemia which has been shown to be associated with poorer health outcomes such as the development of downstream complications and increased mortality. Currently, there is no universally accepted measure of multimorbidity. The literature has suggested that the type as well as number of conditions are both important when considering multimorbidity. It has been suggested that multiple conditions in those with type 2 diabetes should be categorised as concordant (diabetes-related) or discordant (unrelated). While the associations between multimorbidity, glycaemia (HbA1c) and all-cause mortality in people with type 2 diabetes has been studied to some extent, significant gaps remain in the existing literature. In particular, the effects of different patterns of multimorbidity including concordant and discordant conditions have not been studied extensively. Similarly, little is known about the relationships between multimorbidity and emerging novel glycaemic measures, such as glycaemic variability and time-in-range. These new ways of understanding glycaemia may be important independent risk factors for developing complications in people with type 2 diabetes. Aim To explore associations between multimorbidity, all-cause mortality and glycaemic outcomes, including HbA1c and novel measures of glycaemic variability and time-in-range in people with type 2 diabetes. Methods My PhD includes a systematic review and three quantitative studies of more than 150,000 people with type 2 diabetes utilising UK, Taiwan and Australian datasets. This provides a clearer picture of the implications of multimorbidity for people with type 2 diabetes in different populations from different countries, health settings, healthcare systems and of different ethnicities. Results The findings of my studies identified that multimorbidity was highly prevalent among people with type 2 diabetes. More than 80% of the 150,000 people included in my studies were found to have at least one other chronic condition in addition to type 2 diabetes. I found the associations between multimorbidity, mortality and glycaemia were mostly consistent across my studies. Increasing multimorbidity was significantly associated with increased all-cause mortality. This was the case for total count of multimorbidity, as well as counts of concordant and discordant conditions. Increasing concordant counts had the greatest effect on mortality. However, when examining the effects of individual conditions and combinations of two conditions on mortality in the UK and Taiwan cohorts, the results differed between Caucasian and ethnic Chinese populations. I also found that across my studies, all measures of multimorbidity were not associated with higher HbA1c, glycaemic variability and time-in-range. Conclusion This PhD has contributed a novel and deeper understanding of the significance of multimorbidity in people with type 2 diabetes. It has provided an insight into the effects of different patterns of multimorbidity, including concordant and discordant conditions, on important health outcomes in different cohorts of people with type 2 diabetes. My findings highlight the need for clinical guidelines to support a holistic approach to the complex care needs of those with type 2 diabetes and multimorbidity, accounting for the various conditions they be may be living with. While managing glycaemia in people with diabetes is important, it should not overshadow efforts to address multimorbidity, both concordant and discordant. It is important to consider the overall multimorbidity disease burden as a way of recalibrating and personalising our clinical focus in supporting people with diabetes. By taking a holistic approach and caring for the whole person, this could potentially reduce their annual mortality risk by reducing the overall burden of multimorbidity.
KeywordsType 2 diabetes; Multimorbidity; All-cause mortality; Glycaemia
- Click on "Export Reference in RIS Format" and choose "open with... Endnote".
- Click on "Export Reference in RIS Format". Login to Refworks, go to References => Import References