To describe the prevalence of cardiovascular disease (CVD) at the time of diagnosis of adult-onset type 1 (T1D) and type 2 (T2D) diabetes, in a recent cohort and compare to a previous cohort from the same region. Further, to explore factors influencing the prevalence of pre-existing CVD, including age, sex, body mass index (BMI) and C-peptide; in the later cohort also heart failure, hyperlipidaemia, tobacco use and physical activity.

Two prospective cross-sectional cohort studies compared.

All primary health care centres and hospitals in Kalmar and Kronoberg counties in Southeastern Sweden.

Adults with newly diagnosed T1D or T2D (classified by combination of islet antibodies and C-peptide) in 1998–2001 and 2016–2017.

Prevalence of hypertension and CVD at diagnosis of diabetes, and associations with beta-cell function, in two cohorts collected 15 years apart. Further, to explore factors influencing the prevalence of hypertension and CVD, and level of C-peptide.

In patients with newly diagnosed T2D, mean age-at-onset had decreased (66±14.1 years vs 63±12.6, p≤0.001) and mean BMI had increased (29.0±5.4 vs 31.4±5.8 kg/m², p≤0.001). Prevalence of pre-existing myocardial infarction had decreased in both T1D (18% vs 7%, p=0.03) and T2D (25% vs 11%, p≤0.001). Pre-existing hypertension had increased in both T1D (23% vs 40%, p=0.01) and T2D (44% vs 61%, p≤0.001). C-peptide level was lower and was associated with several cardiovascular conditions in newly diagnosed T2D in 2016–2017 (p=0.048 p≤0.001).

Patients with newly diagnosed T2D were younger, with higher BMI, compared with 15 years earlier, a challenge for diabetes care. Prevalence of pre-existing myocardial infarction had decreased notably, in line with, but still less than in the general population; while pre-existing hypertension had increased, in both diabetes types. C-peptide was associated with several cardiovascular conditions in newly diagnosed T2D in the recent cohort, which warrants further investigation.