Diabetes is a long-term illness that causes high blood sugar levels. There are two main types of diabetes: type 2 diabetes (T2D), which occurs in middle-aged persons; and type 1 diabetes (T1D), which generally occurs at young ages; both types of diabetes increase the risk of several diseases, in particular of the heart (for example, heart attack).
However, the development of complications may differ between the two types of diabetes: for example, diseases may occur more frequently in T2D than T1D. Moreover, also the type of the complications may vary, for example heart attacks may be more common in T2D than T1D. At the same time, other factors, which are generally known as "risk factors" (such as obesity, high blood pressure, or the duration of diabetes), may also play a different role in the development of the diseases or the risk of death between the two types of diabetes. Therefore, it is important to detail the risk of developing different disease in relation to the risk factors and to the type of diabetes, and to compare this risk to people without diabetes.
Using information collected by primary care doctors, this study aims to describe the trajectories of the risk factors, diabetes diseases, and the risk of death in individuals with T1D, T2D, and without diabetes, and to explore the effect of the risk factors on the development of the diseases and death.
To date, there are no available studies which have detailed the natural history of diabetes complications from diabetes diagnosis in individuals with T1D and T2D, and how this history is influenced by the characteristics of the patients. Using CPRD data linked to HES APC and ONS, the current study will investigate the development of a single and multiple diseases in individuals with T1D and T2D, and compare the longitudinal trajectories between diabetes types and to people without diabetes. In particular, risk factors (i.e., body mass index, deprivation, glucose control, smoking, duration of the diseases) will be evaluated when the disease is diagnosed (and in the matched control population) and during the evolution of the disease, within each of the three sub-cohorts (T1D, T2D, no diabetes) and in comparisons across sub-cohorts. The relative and absolute risk of developing a single disease (monomorbidity) and multiple diseases (multimorbidity) will be quantified within each sub-cohorts and differences between sub-cohorts estimated. Furthermore, the associations between the (time-varying) risk factors on the transitions across complications and mortality will be estimated. The results of these investigations are of public health relevance, given the rise in the incidence and prevalence of diabetes (particularly type 2 in younger ages), the longer life expectancy in individuals with diabetes, and the potential resulting greater burden of multimorbidity in this population. Defining the temporal development of different complications could indeed guide the implementation of strategies (for example, screening) to identify earlier the risk of specific complications, allowing an early treatment to reduce the risk of mortality. Furthermore, these results may be used to estimate the cost-benefit of population-wide strategies to reduce the burden of multimorbidity in complications in individuals with diabetes.
Fatal and non-fatal complications that have been deemed relevant in the investigations of multimorbidity, including but not limited to cardiovascular, neurological, respiratory diseases, and cancers: this decision aligns with a recent consensus on multimorbidity.[1] The absolute and relative risks of these complications over time, as well as of mortality, will be estimated within each of, and compared across, the three sub-cohorts an compared to the general population and a CPRD cohort of individuals without diabetes.
Francesco Zaccardi - Chief Investigator - University of Leicester
Francesco Zaccardi - Corresponding Applicant - University of Leicester
Alessandro Rizzi - Collaborator - University of Leicester
Cameron Razieh - Collaborator - University of Leicester
Clare Gillies - Collaborator - University of Leicester
Kamlesh Khunti - Collaborator - University of Leicester
Mohammad Ali - Collaborator - University of Leicester
Navjot Kaur - Collaborator - University of Leicester
Setor Kunutsor - Collaborator - University of Leicester
Sharmin Shabnam - Collaborator - University of Leicester
HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation