People who develop diabetes during childhood may die up to 20 years sooner than people without diabetes, according to research findings by scientists in Sweden and the U.K. A study of more than 27,000 individuals with type 1diabetes (T1D) discovered that the average lifespan of women diagnosed with the disorder before the age of 10 years was 17.7 years shorter – the range was 14.5–20.4 years – than that of their diabetes-free counterparts. For men, a diagnosis before 10 years of age was associated with a 14.2 years average shorter lifespan (range 12.1–18.2 years). Lifespan was also on average 10 years shorter for men and women combined, when disease developed later, between 26–30 years of age, according to the research results, which were published in The Lancet.
“These are disappointing and previously unknown figures,” comments Araz Rawshani, M.D., Ph.D., researcher at the department of internal medicine, Sahlgrenska Academy, Gothenburg University, and the Swedish National Diabetes Registry. “The study suggests that we must make an even greater effort to aggressively treat patients diagnosed at an early age to reduce the risk of complications and premature death.”
The research team reports its findings in a paper titled, “Excess mortality and cardiovascular disease in young adults with type 1 diabetes in relation to age at onset: a nationwide, register-based cohort study.”
T1D can develop at any point in life, but is the second most common chronic childhood disease, the authors write. And although there have been “remarkable” improvements in management and survival, T1D is still associated with a two to eight times increase in mortality. Cardiovascular disease is the main driver of morbidity and mortality in people with the disease, so guidelines in Europe and the U.S. recommend aggressive management of cardiovascular risk factors in T1D patients, and in particular those over the age of 40 years. However, there are currently no guidelines that consider age of disease onset as stratifier of risk, the authors point out. “… we aimed to do a nationwide, register-based cohort study to examine how age at diagnosis of type 1 diabetes relates to excess risk of death and cardiovascular outcomes, while accounting for diabetes duration, using granular age categories.”
The researchers analyzed data from 27,195 T1D patients the Swedish National Diabetes Register, and another 135,178 matched controls, including an average of 10 years of follow-up. The analyses were designed to estimate the excess T1D-related risk of all-cause mortality, as well as cardiovascular mortality, noncardiovascular mortality, acute myocardial infarction (AMI)), stroke, cardiovascular disease (a composite of AMI and stroke), coronary heart disease, heart failure, and atrial fibrillation. Patients were categorized into five groups, based on their age at T1D diagnosis: 1–10 years, 11–15 years, 16–20 years, 21–25 years, and 26–30 years.
The results showed that for both men and women combined, a T1D before 10 years of age was associated with an average of 16 life-years lost. T1D patients were also at greater risk of all of the outcomes evaluated, apart from atrial fibrillation. The earlier the disease developed, the greater the risk. “Patients with type 1 diabetes with disease onset before 10 years of age had a 30-times increased risk of coronary heart disease and acute myocardial infarction compared with matched controls,” the researches write. “There was a ubiquitous inverse association between age and diagnosis and risk of outcomes.”
And among those who developed T1D before 10 years of age, the risks were much higher in women than they were in men. Women had a six-times increased risk of all-cause mortality, whereas for men the risk was increased threefold. “Excess risks were particularly pronounced in women,” the authors note; “women with type 1 diabetes had an approximately 60-times increased risk of coronary artery disease and an approximately 90-times increased risk of acute myocardial infarction.”
Given the findings that age of T1D onset appears to be a key determinant of survival and cardiovascular risk factors, independent of disease duration, the researchers suggest that patients with earlier-onset T1D should be offered cardioprotective medicines, such as statins and blood pressure-lowering drugs, much sooner than is the current practice. “Increased efforts towards improved glycemia control and, where relevant, smoking cessation, in such individuals would also be beneficial,” they noted.
“The study opens up the potential for individualized care,” Dr. Rawshani comments. “We know with certainty that if we maintain good blood sugar control in these patients, we can lower the risk of cardiovascular damage. This makes it important to carefully consider both evidence-based medications and modern technological aids for blood sugar measurements and insulin administration in patients diagnosed with type 1 diabetes at an early age.”
The results are particularly important from a patient’s perspective, he continues. “Suddenly we can answer questions about complications and life expectancy that we were previously unable to answer. Now there is robust evidence that survival largely depends on the age at which the patient develops the disease, and that there is a difference between men and women.”
The findings have major relevance in Sweden, where there are about 50,000–60,000 people with T1D, and where the majority of diagnoses are made in children aged 10–14 years. The incidence of childhood diagnosis in the country is also increasing and is among the highest worldwide, with Sweden being second only behind Finland. “At the same time the study must also be viewed in the light of the tremendous progress that has been made in the past few decades,” Dr. Rawshani acknowledges. “Management of type 1 diabetes is nowadays highly sophisticated, with modern tools for glucose monitoring, delivery of insulin and management of cardiovascular risk factors. Those who live with diabetes today, and those who will acquire the disease, will enjoy longer and healthier lives in the years to come.”
