Adults diagnosed with type 1 diabetes have a higher risk of early mortality and major adverse cardiovascular events compared with those without diabetes, according to a large study from Sweden.

Investigators followed over 10,000 adult patients with type 1 diabetes and compared their health outcomes with more than 500,000 individuals without diabetes and over 375,000 patients with type 2 diabetes.

The patients with adult-onset type 1 diabetes had a 71% higher risk of all-cause mortality and a 30% higher risk of major adverse cardiovascular events (MACE), such as heart attacks or strokes, compared with the general population. These risks were consistent regardless of whether the diagnosis occurred at age 18 years or after 40 years.

Compared with those with type 2 diabetes, adult patients with type 1 diabetes had lower rates of MACE but a higher risk of mortality from diabetic coma or ketoacidosis—seven times greater.

Three key risk factors contributed most to poor outcomes: smoking, elevated blood sugar levels (HbA1c ≥ 53 mmol/mol), and overweight or obesity. Together, these accounted for nearly 20% of deaths and 40% of cardiovascular events in patients with type 1 diabetes.

Those with poor glycemic control had a 23% higher risk of mortality, while smokers had a 76% increased risk compared with nonsmokers. Obesity was also associated with greater risks of mortality and cardiovascular complications.

Risk increased with the number of these health issues. One risk factor was associated with a 41% higher risk of mortality, while three or more nearly tripled that risk. In contrast, patients with no major risk factors had health outcomes similar to those without diabetes.

Patients diagnosed at 40 years or older had poorer blood sugar control over time. After 12 years, 77% of older adults didn't meet blood sugar targets compared with 67% of younger adults.

Older adults were also less likely to use insulin pumps. At the end of follow-up, 14% of those diagnosed at 40 years or older used insulin pumps compared with 26% of younger patients.

Male patents with type 1 diabetes had higher mortality rates compared with female patients, particularly from diabetic coma, cancer, and infections. This sex-related difference remained after adjusting for smoking, blood pressure, and other clinical factors.

The investigators concluded that improved long-term care strategies are needed for adult patients diagnosed with type 1 diabetes. Addressing smoking, glycemic control, and weight management may reduce the risk of severe complications.

The investigators analyzed national health registry data in Sweden, with a median follow-up of 10 years. Data were adjusted for socioeconomic and demographic variables to ensure accurate comparisons.

Full disclosures are available in the published study.

Source: European Heart Journal