About the project
The OMIT cohort is a new Norwegian registry-based observational cohort, constructed to study key high-risk patients-groups with T2D often omitted from randomized clinical trials. The patient groups with T2D at focus are:
- T2D diagnosis at age under 40 years
- Patients with low socio-economic status and/or belong to ethnic minority
- Elderly patients with age over 75 years.
For a visual representation, please see Figure 2 in the article "Cohort profile: Outcomes & Multimorbidity In Type 2 diabetes (OMIT) – a national registry-based observational cohort with focus on care and treatment of key high-risk groups in Norway" in BMJ Open.
We have identified three key high-risk patient groups
Young Onset Diabetes (YOD)
- Young Onset Diabetes (YOD) is defined as diabetes onset prior to 40 years of age
- By 2013 61 million YOD patients worldwide, equal to 16% of the global T2D population
- YOD patients have higher BMI, higher levels of HbA1c, blood pressure and lipids when diagnosed
- YOD patients exhibit higher mortality, shorter life-expectancy and higher complication rates
Low SES or ethnic minorities
- Ethnic minorities and low socioeconomic status (SES) patients display a higher risk for T2D and develop the disease at an earlier age
- South Asians acquire their diabetes at a substantially younger age and lower BMI than European origin populations
- Risk of YOD increases with lower socioeconomic status (SES) and psychosocial strain
- The possible relationship between SES and age of onset of T2D has only been vaguely studied
Elderly patients (over 75 years of age)
- A heterogeneous group: long-term survivors of T2D with late-stage complications or patients with multi-morbidity prior to a T2D diagnosis
- Constitute another clinically important group that may be frail
- May be particularly susceptible to adverse drug effects and drug interactions, especially in a context of polypharmacy
The project has obtained ethical approval from Regional Committees for Medical Research Ethics - South East Norway (REC South East (Ref number 74012)) and is approved by the Data Protection Official/Officer at Oslo University (UiO). Data linkage began in mid-2020 for the years 2006–2019. In the OMIT-cohort, all data are encrypted, and researchers will therefore not in any way be able to identify individual patients.
The OMIT cohort is constructed via multiple linkages to key high-quality national data registries, with subjects with T2D being identified and enrolled from the Norwegian Diabetes Register for Adults (NDR-A) (N equals 47 285) and the Rogaland-Oslo-Salten-Akershus-Hordaland (ROSA4) study (N equals 10242) and includes data until December 31st 2019.
Objectives
With the OMIT cohort project, we aim to answer the following broad research questions:
- How does multi-morbidity interact with diabetes development and care, and how does it relate to intermediate (e.g., HbA1c, low-density lipoprotein and/or blood pressure) and harder disease outcomes (e.g., diabetes-specific complications and/or death)?
- How do newer antidiabetic drugs perform in terms of real-life effectiveness (e.g., as opposed to drug efficacy, which can be measured only in randomized clinical trials), cost-effectiveness, safety and adherence in high-risk groups?
- What are the causes and effects of diabetes control variability on intermediate and harder disease outcomes and how is the organization of diabetes care related to these outcomes?
Outcomes
To answer the overall research questions, we have planned several individual studies to investigate the following outcomes in key high-risk patient groups (ranked in descending order according to number of planned studies). For a visual representation of the outcomes, please see Figure 1 in the article "Cohort profile: Outcomes & Multimorbidity In Type 2 diabetes (OMIT) – a national registry-based observational cohort with focus on care and treatment of key high-risk groups in Norway" in BMJ Open.
Primary outcomes
- Multimorbidity, (2) diabetesspecific complications, (3) mortality/survival, (4) variability in disease control (eg, variability in relation to intermediate disease outcomes), (5) drug effectiveness and cost-effectiveness, (6) drug adherence and (7) YOD.
Secondary outcomes
- Anatomical Therapeutic Chemical (ATC) classification code based comorbidity, (2) mortality, (3) diabetes-specific complications, (4) drug adherence, (5) drug treatment cascade, (6) drug effectiveness and cost-effectiveness, (7) polypharmacy and risk of potentially adverse drug interactions, (8) variability in disease control (e.g., variability in relation to intermediate disease outcomes), (9) YOD and (10) disability pension/sick leave.
Background
The prevalence of type 2 diabetes (T2D) is increasing worldwide, and so is the burden of related vascular complications and death. Although timely and efficacious interventions may improve outcomes and reduce the economic burden, the evidence for current treatment regimens is often limited in patients with greater needs as they are often omitted from clinical trials.
Consequently, we need more evidence to better understand the current unmet needs and evidence documenting the effectiveness, cost-effectiveness and safety of various treatments and clinical procedures in relation to how they may impact both disease control and harder disease outcomes in high-risk patients.
As high-risk patients have proven difficult to include in prospective interventional trials, instead we see a great opportunity to employ non-interventional, observational data already present in various high-quality national registries.
Sub-projects
The research projects of the OMIT-cohort are organized into to three work packages:
- WP 1: The burden of multi-morbidity
- WP 2: Real-life drug utilization & performance
- WP 3: Variability in disease control (quality of care)
Please see Figure 3 in the article "Cohort profile: Outcomes & Multimorbidity In Type 2 diabetes (OMIT) – a national registry-based observational cohort with focus on care and treatment of key high-risk groups in Norway" in BMJ Open for a full overview of how we plan to employ individual covariates as exposures, mediating and/or confounding covariates and/or outcomes in the individual research studies planned.
Financing
The first phase of linkages was funded by the University of Oslo. Currently, senior researchers and one postdoctoral position (Western Norway University of Applied Sciences (HVL), Norway) are funded by their home institutions. The cohort is also funded by The Norwegian Diabetes Association (Diabetesforbundet) and the Norwegian Research Fund for General Practice (Allmennmedisinsk forskningsfond), with the latter also funding one PhD-student (University of Oslo (UiO), Norway).
Project start and finish
Start: January 1st 2021
End: December 31st 2035