A long-term European study published in Cardiovascular Diabetology has found that certain trace elements in the blood may be linked to future risks of vascular complications in people who later develop the disease.

The study analyzed data from 627 individuals in the EPIC-Potsdam cohort who developed diabetes during the follow-up period. All participants were free of vascular complications at baseline and had available blood measurements for trace elements taken before their diabetes diagnosis. These included selenium, zinc, copper, manganese, iodine, and iron.

The participants were followed for a median of 12.8 years to track the onset of diabetes-related microvascular complications (like retinopathy or nephropathy) and macrovascular complications (like heart attack or stroke). Over the follow-up period, 212 participants developed microvascular complications, and 69 developed macrovascular ones.

Researchers found that higher pre-diagnosis iodine levels were linked to a greater risk of developing overall vascular complications (hazard ratio [HR] per standard deviation [SD] increase: 1.16; 95% CI: 1.02–1.31) and microvascular complications (HR: 1.18; 95% CI: 1.03–1.35). These associations maintained their significance even after adjusting for potential confounders such as lifestyle, age, and metabolic risk factors.

When results were analyzed by sex, women with higher zinc levels had a notably higher risk of total vascular complications (HR: 1.35; 95% CI: 1.06–1.73) and microvascular complications (HR: 1.52; 95% CI: 1.15–2.02). In contrast, higher zinc levels were linked to an enhanced risk of macrovascular complications (HR: 1.33; 95% CI: 1.00–1.77) in men.

In women, a higher copper-to-zinc ratio was associated with a reduced risk of microvascular complications (HR: 0.69; 95% CI: 0.54–0.88). But in men, the same ratio was linked to an elevated risk (HR: 1.54; 95% CI: 1.17–2.02).