ADHD and Type 2 Diabetes: What a Large International Study Found About Heart Risk and Survival

Doctors have long known that type 2 diabetes raises the odds of heart attacks, strokes, and early death. A new multi-national study asks a less familiar question: does having ADHD alongside diabetes change that picture? And does taking ADHD medication make a difference, for better or worse?

The research, published in BMC Medicine, pulled together health records from seven countries — Australia, Denmark, the Netherlands, Norway, Sweden, the UK, and the US — covering nearly 1.9 million adults diagnosed with type 2 diabetes between 2010 and 2020. The team tracked what happened to these adults afterward, specifically looking at major adverse cardiac events (heart attack, stroke, or cardiovascular death) and death from any cause.

A Higher Mortality Signal, But Not More Heart Events Overall

Adults with both ADHD and type 2 diabetes had a notably higher rate of dying from any cause after their diabetes diagnosis compared with peers who had diabetes but no ADHD — more than double the rate, according to the pooled analysis across countries. This is an association drawn from observational data, not proof that ADHD itself causes earlier death.

The same pattern didn't hold for major cardiac events specifically. Across the full study population, having ADHD wasn't consistently linked to a higher rate of heart attacks, strokes, or cardiovascular death once the data from all countries were combined. The mortality finding, in other words, doesn't appear to be fully explained by cardiac causes — something the authors suggest points toward other contributing factors, such as how ADHD might affect engagement with diabetes care, broader health behaviors, or co-occurring conditions.

Medication Use and Early-Onset Diabetes

The study also looked specifically at people who had both ADHD and diabetes, comparing those who used ADHD medication with those who didn't. Overall, medication use wasn't linked to a broad increase in cardiac events across the whole group. But a more specific pattern emerged among adults who had developed type 2 diabetes before age 45: in this younger-onset subgroup, ADHD medication use was associated with a higher rate of major cardiac events, around 58% higher compared with non-use.

This adjustment held up even after the researchers accounted for factors like sex, age, the year diabetes was diagnosed, psychiatric history, use of other psychiatric medications, and use of cardiometabolic drugs. The authors stop short of saying ADHD medications directly cause cardiac harm in this group — people who continue ADHD medication into adulthood with early-onset diabetes may differ from others in ways the study couldn't fully measure, including symptom severity, lifestyle factors, or underlying cardiometabolic vulnerability.

ADHD, Diabetes, and the Mortality Gap

Type 2 diabetes is already recognized as a major driver of cardiovascular risk and reduced life expectancy on its own. ADHD has separately been linked in prior research to a roughly doubled risk of developing type 2 diabetes in the first place. Taken together, this new study adds another layer: once diabetes is present, co-occurring ADHD appears tied to worse survival outcomes, even if the mechanism isn't yet clear.

The researchers point out that adults with ADHD often face additional hurdles in managing chronic physical conditions — things like maintaining consistent follow-up care, adhering to medication regimens, or sustaining lifestyle changes that diabetes management typically requires. They suggest that more coordinated care between mental health and physical health providers could be worth exploring for this group, particularly for younger adults who developed diabetes earlier in life and are using ADHD medications.

What the Study Can't Prove

This is a large cohort study built from health records across several countries, which gives it statistical power and broad applicability. But the people included weren't randomly assigned to have ADHD or to take medication for it, so differences between groups — in severity of illness, access to care, or other health conditions — could be influencing the results in ways statistical adjustment can't fully capture. That limitation applies across all the findings above: a strong association, even a consistent one, isn't the same as a demonstrated cause.

None of this is a reason for anyone taking ADHD medication, with or without diabetes, to make changes on their own. Decisions about starting, continuing, or stopping any medication should be made with a doctor who knows a person's full medical history, especially when multiple chronic conditions are involved. This study is a signal for more research and clinical attention, not a basis for personal medical decisions.

Source: BMC Medicine, DOI: 10.1186/s12916-026-05246-4, based on a multi-national cohort study by Dong et al.