University of Copenhagen Research Shows Heart Health Impact of Diabetes Medication Adherence

University of Copenhagen Research Shows Heart Health Impact of Diabetes Medication Adherence

(IN BRIEF) Researchers at the University of Copenhagen and their collaborators found that adults with type 2 diabetes who do not consistently take their prescribed glucose-lowering medication have a higher rate of cardiovascular disease. The study followed 79,510 adults newly diagnosed with type 2 diabetes over a ten-year period using Denmark’s national health registries and monthly pharmacy records. Patients with low medication adherence had a 27 percent higher rate of major cardiovascular events compared with those who consistently took their medication. The association was stronger for ischemic heart disease, at 45 percent, and stroke, at 24 percent. The risk was especially high among younger adults, where low adherence was linked to a 73 percent higher rate of cardiovascular events before the age of 55. The researchers said the findings support early, personalised support to help patients stay on treatment.

(PRESS RELEASE) COPENHAGEN, 7-Aug-2026 — /EuropaWire/ — Adults with type 2 diabetes who do not take their prescribed medication consistently have a significantly higher rate of cardiovascular disease, including heart attacks and strokes, new research from the University of Copenhagen and its collaborators has found.

The study, led by Associate Professor Jordi Merino from the Novo Nordisk Foundation Center for Basic Metabolic Research, known as CBMR, at the University of Copenhagen, tracked medication adherence among nearly 80,000 adults over a ten-year period.

The researchers found that people who consistently followed their prescribed diabetes treatment remained free from serious heart and circulatory complications for more than seven additional months compared with those who did not take their medication consistently.

Type 2 diabetes is associated with an increased risk of cardiovascular disease.

Many people with the condition are prescribed blood sugar-lowering medication to help reduce this risk.

These treatments support blood sugar control, which is important because high blood sugar over many years can damage blood vessels and the heart, increasing the likelihood of heart attacks and other cardiovascular complications.

However, not all patients are able to take their medication consistently over time.

Until now, researchers have found it difficult to determine how long-term adherence to diabetes medication affects the risk of heart attack, stroke and other major cardiovascular events.

To examine real-world medication habits, the research team analysed data from Denmark’s national health registries.

The study included 79,510 adults who were newly diagnosed with type 2 diabetes and began non-insulin glucose-lowering treatment between 2005 and 2012.

Rather than relying on self-reported information, the researchers used monthly pharmacy prescription records over a ten-year period.

This approach allowed the team to identify three long-term adherence patterns.

Around 41 percent of patients maintained high adherence to their medication.

A further 33 percent followed a moderate adherence pattern, while 26 percent showed early decline and persistently low adherence.

Patients in the low-adherence group had a 27 percent higher rate of major cardiovascular events compared with those who took their medication consistently.

Patients in the intermediate adherence group had a 7 percent higher rate.

The association was strongest for ischemic heart disease, where low adherence was linked to a 45 percent higher rate.

Low adherence was also associated with a 24 percent higher rate of stroke.

The findings were particularly pronounced among younger adults.

Among younger patients, low adherence was linked to a 73 percent higher rate of experiencing a cardiovascular event before the age of 55, compared with patients who consistently took their medication.

The researchers noted that developing type 2 diabetes earlier in life can expose patients to a longer period of potential damage to blood vessels, making consistent treatment especially important during working and family years.

The study also highlighted social factors linked to medication adherence.

People in the low-adherence group were more likely to live alone, have lower incomes and manage other chronic conditions.

The researchers said this suggests that inconsistent medication use is rarely a matter of forgetfulness alone and may reflect broader pressures in a patient’s life.

The research team adjusted its analysis for socioeconomic indicators and other relevant factors.

They also conducted sensitivity analyses.

Even after these adjustments, people who were less adherent to diabetes medication remained at higher risk of developing cardiovascular disease.

Associate Professor Jordi Merino said prescribing the right medicine is only the first step.

He said the study shows that a patient’s ability to continue taking treatment over the following years has a direct bearing on heart health.

Merino said the findings support the need for personalised support early after diagnosis, rather than assuming that providing a prescription is enough.

Lise B. Nielsen, first author of the study and researcher at CBMR, said the findings show that health systems need to look beyond occasional checks of medication habits.

She said access to medicine does not automatically mean that a person is able to take it every day.

Nielsen added that tracking long-term medication habits could help doctors identify vulnerable patients before a major heart event occurs.

The researchers noted that the study is observational, meaning it cannot prove that poor medication adherence directly causes cardiovascular disease.

However, the findings are consistent with broader evidence showing that maintaining good blood sugar control through appropriate treatment can help reduce the risk of cardiovascular complications.

The study used prescription redemption as a proxy for medication intake, a standard approach in registry-based research.

The researchers also noted that the study did not measure certain external factors, such as blood sugar regulation, body mass index or lifestyle behaviour.

The study was partly supported by grants from the Novo Nordisk Foundation, which the researchers said had no influence on the study design or publication.

The research was published in The Lancet Regional Health – Europe under the title “Long-term adherence to glucose-lowering therapy and cardiovascular risk in type 2 diabetes: a nationwide cohort study.”

Researchers from the University of Copenhagen who contributed to the study include Lise B. Nielsen, Andreas Bartholdy, Tri-Long Nguyen, Majken K. Jensen, Simon Rasmussen, Marta Guasch-Ferré and Jordi Merino.

Through the study, the University of Copenhagen researchers underline the importance of long-term treatment support for people with type 2 diabetes and point to medication adherence as a key factor in reducing cardiovascular risk.

About the research

• Because the study is an observational study, the researchers cannot prove that poor medication adherence directly causes heart disease. However, the findings are consistent with extensive evidence showing that maintaining good blood sugar control through appropriate treatment helps reduce the risk of cardiovascular complications.
• People who do not take their prescribed medications are often more likely to have other challenges, such as lower incomes, living alone, or additional health conditions, which can also affect their heart health. Additionally, the study does not measure potential outside factors like blood sugar regulation, body mass index or lifestyle behaviour.
• The researchers account for this by adjusting for socioeconomic indicators and through a number of sensitivity analyses. They still found that people who were less adherent to their diabetes medications had a higher risk of developing cardiovascular disease.
• Prescription redemption was used as a proxy for medication intake, however this is a standard practice for registry-based studies.
• The study and the researchers were partly supported by grants from the Novo Nordisk Foundation. This had no impact on the design and publication of the study.
• The study is published in the scientific journal The Lancet Regional Health – Europe.
• Researchers from the University of Copenhagen who contributed to the study include: Lise B. Nielsen, Andreas Bartholdy, Tri-Long Nguyen, Majken K. Jensen, Simon Rasmussen, Marta Guasch-Ferré and Jordi Merino.

Media Contacts:

Jordi Merino
Associate Professor
Novo Nordisk Foundation Center for Basic Metabolic Research
Email: Jordi.Merino@sund.ku.dk
Phone: +45 51 42 40 55

Lise Birk Nielsen
Researcher
Novo Nordisk Foundation Center for Basic Metabolic Research
Email: lise.birk@sund.ku.dk

Peter Andrew Stanners
Senior Consultant
Novo Nordisk Foundation Center for Basic Metabolic Research
Email: peter.stanners@sund.ku.dk
Phone: +45 93 50 94 59

William Brøns Petersen
Communications Consultant
UCPH Communication
Email: william.petersen@adm.ku.dk
Phone: +45 93 56 55 80

SOURCE: University of Copenhagen