Study explored eighteen physical and mental health conditions to assess their role as comorbidities in type 2 diabetes.
Approximately 422 million adults across the world have diabetes. Diabetes contributes to the global economic burden and increases the chances of premature mortality. Individuals who have type 2 diabetes are prone to premature mortality. As life expectancy has increased, so has the population of older individuals who experience multimorbidity. Multimorbidity is when an individual has more than one chronic condition present at the same time. Nearly 44%-95% of individuals with diabetes have at least one comorbid condition. A Dutch study showed a positive correlation between the number of comorbidities in a person with diabetes and the amount of healthcare utilized. Previous studies only focus on cardiovascular disease associated with comorbidities with diabetes. There is not much data on the profile of prevalent mental and physical illnesses associated with T2D.
The study is a population-based cohort whose purpose is to explore eighteen physical and mental health conditions stratified by age, gender, and deprivation in people with and without T2D by using hospitalization and primary care data over 11 years in England. A metric was developed to determine what the most prevalent comorbidities with T2D were, and then addressed whether each comorbidity was discussed in the national diabetes guidelines. 108,588 participants with T2D and 528,667 comparators were registered to general practice for ≥ 90 days. The participants with T2D must be ≥ 16 and diagnosed for the first time with T2D with a medical code between 01/01/2004 and 12/31/2014. Five participants without diabetes were matched to a participant with T2D each year based on age (+/- 2 years difference), gender, and general practice. Each participant who was matched had the same index/diagnosis date.
The Clinical Practice Research Datalink (CPRD) GOLD, which stores all the medical records from general practices throughout the UK, is the electronic database used. The Hospital Episode Statistics (HES) was used to collect secondary care data. The diagnostic Read and International Classification of Diseases (ICD-10) codes were obtained from previous literature and used to determine diagnosis during primary care or hospitalization. The 18 comorbidities included asthma, chronic obstructive pulmonary disease (COPD), hypothyroidism, osteoarthritis (OA), chronic kidney disease (COPD), anxiety, depression, epilepsy, schizophrenia, hyperlipidemia, hypertension, atrial fibrillation (AF), congestive heart failure (CHF), myocardial infarction (MI), peripheral vascular disease (PVD), transient ischemic attack (TIA), cancer and stroke. Additional criteria were placed on asthma, anxiety, cancer, depression, and epilepsy since they can be resolved at later stages.
Annual prevalence rates and 95% CI were calculated for the matched patients’ comorbidities over the study period. A coexisting two comorbidities pattern was obtained and compared between those who have T2D and those who do not. The annual prevalence of cardiovascular disease cluster for the overall population and gender-specific was calculated for those with and without T2D. A logistic regression model was used to estimate OR and 95% CI for the link between the 18 comorbidities and T2D. Metric using 2014 data was used for comorbidities with a prevalence of ≥ 5% and/or odds ≥ 2% in patients with T2D.
Individuals with T2D had more prevalence of all comorbidities than those without diabetes. Cardiovascular conditions and risk factors prevalence was twofold higher in participants with T2D. Most age-specific comorbidities increased in prevalence in participants with T2D, except asthma, which was the same, and depression, which was less prevalent in participants ≥ 56 years in both groups. Hypothyroidism was almost four-times higher in females, while MI was more prevalent in males in both groups. Asthma, COPD, anxiety, and depression in participants diagnosed with T2D in 2014 was higher in those that were socially deprived. Participants with T2D were at higher odds for MI (OR 2.13, 95%CI 1.85 to 2.46); heart failure (OR 2.12, 1.84 to 2.43); depression (OR 1.75, 1.62 to 1.89). Comorbidities like OA, hypothyroidism, asthma, COPD, anxiety, depression, and schizophrenia that are not commonly associated with T2D showed high prevalence with T2D. A strength of the study includes examining 18 comorbid physical and mental conditions as opposed to just cardiovascular disease when assessing the association of comorbidities’ prevalence. A limitation of the study is its reliance on recorded diagnosis and the possibility of missing undiagnosed patients. Future studies should include analyzing non-cardiometabolic conditions in patients with T2D.
- Cardiovascular disease is twice as likely in individuals with T2D than the general population.
- Multiple comorbidities are prevalent in patients with T2D, including diseases less commonly associated with it.
- Age and social deprivation can influence the prevalence of comorbidity.
Zghebi, Salwa S et al. “Eleven-Year Multimorbidity Burden Among 637 255 People With And Without Type 2 Diabetes: A Population-Based Study Using Primary Care And Linked Hospitalisation Data”. BMJ Open, vol 10, no. 7, 2020, p. e033866. BMJ, doi:10.1136/bmjopen-2019-033866. Accessed 22 July 2020.
Zahra Hashemy, PharmD. Candidate, USF Taneja College of Pharmacy