Heart Attacks Linked to Low Phosphate Levels

Mid-range levels of phosphate in the blood may reduce the risk of heart attack.

Low phosphate levels in the blood may be associated with an increased risk of heart attack and coronary artery disease, according to a new PLOS One study.

These results suggest that low phosphate levels may be dangerous to the heart, which conflicts with previous studies that show low levels of the mineral are beneficial to heart health.

“The importance of phosphate in primary and secondary healthcare should be reviewed,” said lead author Dr Nick Hayward. “It is often overlooked in blood tests yet phosphate may be a new risk factor for heart disease in adults."

Phosphate is a crucial mineral that regulates blood biochemistry, meaning that its levels can affect how the heart works, according to the authors. Phosphate also allows red blood cells to deliver oxygen throughout the body.

In the study, the authors analyzed phosphate levels for more than 100,000 patients who were followed over 5-year and 9-year intervals. The authors specifically examined the effect of different blood phosphate levels on heart disease.

The authors discovered that patients whose blood phosphate levels were lower than 0.75-mmol/L had a similar risk of coronary artery disease compared with those whose mineral levels were more than 1.5-mmol/L, according to the study.

Cases of coronary artery disease were high among both those with low and high rates of phosphate; however, cardiac events were the lowest among patients with levels in the mid-range (1-mmol/L to 1.25-mmol/L), according to the study.

Although high levels of the mineral have previously been found dangerous to heart health, this is the first time that low levels have also been identified as harmful.

These results suggest that physicians should closely monitor phosphate levels, especially for patients who are at high risk of heart disease, including those with diabetes.

"Our findings shed new light on the role of phosphate in the body and its relationship to cardiovascular health,” said researcher Dr Andy McGovern, BSc, BMBS. "In light of our findings we would suggest that clinicians consider people with low phosphate levels to be at higher cardiovascular risk and assess ways in which this can be reduced for each patient.