Young patients with type 1 at greater risk: those diagnosed before 10 years of age show increased risk of mortality and cardiovascular disease than those diagnosed at an older age.
In a new study published August 2018, investigators from Sweden examined the effects of early age at diagnosis of diabetes on cardiovascular risk and early mortality. Using the Swedish National Diabetes Register between 1998 and 2012, investigators of the study created a cohort of 27,195 individuals with type 1 diabetes mellitus (T1DM). Each patient with T1DM was matched with five controls from the Swedish population based on age, sex, and county.
Participants with T1DM and their matched controls were followed from the time of first registration into the national database to the time of event, death, emigration, or end of study follow-up (2014). Those included in the study were broken into five groups based on age at diagnosis of diabetes: 0-10 years, 11-15 years, 16-20 years, 21-25 years, and 26-30 years. Within these groups, investigators examined the risk of mortality (all-cause, cardiovascular, and non-cardiovascular), myocardial infarction, stroke, coronary heart disease, atrial fibrillation, and heart failure.
Using Cox regression models, investigators determined the association between age at diagnosis of T1DM and the risk of aforementioned outcomes in comparison to matched controls. Hazard ratios were used to show the overall risk of outcomes in patients with T1DM based on age at diagnosis. Each hazard ratio presented in the study characterizes the risk for each group after an average duration of diabetes of 13 years, with no duration greater than 20 years. Investigators chose to limit the duration to 20 years to allow for a “more contemporary cohort” in order to give a better representation of the current diabetes trends.
Results of the study were striking. Looking specifically at life-years lost, both men and women diagnosed with T1DM before age 10 had a resulting average loss of 16 years of life. Comparing this to patients who were diagnosed in the 26-30 years’ age group, those individuals lost an average of only 9.8 years of life. Hazard ratio trends for the nine outcomes studied showed that all-cause mortality and cardiovascular mortality had the greatest hazard ratio in ages 0-10, and lowest in the 26-30 age group. Again, a similar trend was seen for cardiovascular disease, acute myocardial infarction, stroke, and heart failure, with the highest hazard ratios being represented in the 0-10 age group, and the lowest in the 26-30 age group. Individual results are shown below.
|Outcome||0-10 years||26-30 years|
|All-cause mortality||4.11 (3.24-5.22)||2.83 (2.38-3.37)|
|Cardiovascular mortality||7.38 (3.65-14.94)||3.64 (2.34-5.66)|
|Coronary Heart Disease||30.50 (19.98-46.57)||6.08 (4.71-7.84)|
|Cardiovascular Disease||11.44 (7.95-16.44)||3.85 (3.05-4.87)|
|Stroke||6.45 (4.04-10.31)||3.22 (2.35-4.42)|
|Acute MI||30.95 (17.59-54.45)||5.77 (4..08-8.16)|
|Heart failure||12.90 (7.39-22.51)||5.07 (3.55-7.22)|
Overall, the results of this study gave compelling evidence of age at diagnosis of T1DM as an important indicator of health-related outcomes. Patients who developed T1DM before 10 years of age had a 4x greater risk of all-cause mortality than individuals without diabetes. Specifically, women diagnosed with diabetes before 10 years of age were 60 times more likely to develop coronary heart disease and 90 times more likely to experience an acute myocardial infarction than individuals without diabetes. For both men and women diagnosed with T1DM before age 10, these patients had a 12x higher risk of developing heart failure than controls.
Why might this correlation exist between younger age at onset and increased risk of mortality? Investigators of this study believe it may have to do with a more severe and rapid loss of beta cells in patients who are diagnosed earlier in life. While this suggestion is backed by limited studies, the investigators acknowledged the need for further research that may address this theory.
Having quadruple the risk of death simply due to development of diabetes at a young age is a frightening statistic, and one that scientists believe may warrant earlier use of cardioprotective medications in the diabetes community.
- Children diagnosed with type 1 diabetes before the age of 10 years are at greater risk of mortality and cardiovascular disease compared to those diagnosed at an older age.
- Coronary heart disease, stroke, and acute myocardial infarction were just some of the outcomes investigators found to be at highest risk of development in patients diagnosed with type 1 diabetes before 10 years of age.
- Cardioprotective medications may need to be considered in young children who are diagnosed with diabetes at a young age.
Rawshani, Araz, et al. Excess Mortality and Cardiovascular Disease in Young Adults with Type 1 Diabetes in Relation to Age at Onset: A Nationwide, Register-Based Cohort Study. The Lancet, vol. 392, no. 10146, 11 Aug. 2018, pp. 477–486., doi:10.1016/s0140-6736(18)31506-x.
Clarke Powell, Pharm.D. Candidate 2019, LECOM School of Pharmacy