This study examined the link between vitamin D deficiency and coronary heart disease events, like heart attacks, in patients with type 2 diabetes (T2D). It was found that vitamin D deficiency increased the risk of coronary heart disease (CHD) events in these patients. 

CHD is a disease where a fatty substance (plaque) builds up in the arteries supplying the heart. This results in less oxygen being delivered to the heart. This can cause the heart muscle to die, leading to a heart attack. Patients with T2D have a higher risk of developing CHD.

Vitamin D can be taken in food, or made in the skin in response to sunlight. Vitamin D deficiency is common, particularly in patients with T2D. Recent evidence suggests that vitamin D deficiency is associated with an increased risk of CHD events. However, research on the link between vitamin D deficiency and CHD events in patients with T2D is limited.

2607 patients with newly diagnosed T2D were followed at least every 3 months for an average of 8.5 years. Their vitamin D levels, and other characteristics, were measured. The participants were divided into four groups, based on their vitamin D levels. Any CHD events that occurred were noted.

In total 299 participants (11.47%) experienced a CHD event.

Increasing levels of vitamin D decreased the risk of a CHD event. The group with the highest vitamin D levels was 57% less likely to experience a CHD event than the group with the lowest vitamin D levels. The group with the second highest vitamin D levels was 48% less likely.

This effect was different for men and women. Men with the highest vitamin D levels were 49% less likely to experience a CHD event than men with the lowest vitamin D. This figure was 67% for women.

The study concluded that low vitamin D was connected to the risk of CHD events in patients with T2D.

Parathyroid hormone and calcium are affected by vitamin D levels. The researchers did not have information on these factors. Furthermore, they did not receive information about the use of vitamin D supplements in the participants.

Speak to your physician about the risk of CHD events and vitamin D deficiency if you have T2D.