INOCA or ischemia with nonobstructive coronary arteries is a condition often seen in patients with angina. However, its pathophysiology is ill-understood. A study published in the journal Diabetes Care has for the first time shown stress hyperglycemic ratio as a risk factor for re-hospitalization of INOCA patients with or without diabetes.^1,2

In this study, researchers from the United States and Italy examined a total of 2874 patients with symptoms of ischemia but with nonobstructive coronary arteries (INOCA). These patients had been referred to a hospital in Italy for percutaneous coronary intervention (PCI) between January 2016 and January 2021. Through this study, they sought to examine if stress hyperglycemia ratio (SHR) at the time of admission had any effect on the risk of rehospitalization for chest pain in these patients. Stress hyperglycemia ratio was calculated by dividing blood glucose (mmol/L) by HbA1c (%).

After follow-up at one year, patients with SHR greater than 1 were more likely to be re-hospitalized for chest pain compared to patients with SHR less than 1. The risk increased as the SHR value increased. This association remained significant after adjusting for confound variables such as age, BP, BMI, heart rate, diabetes, chronic kidney disease and cholesterol.

Researchers however noted the prevalence of diabetes was higher in patients with SHR >1; they were older in age and had higher HbA1c levels.²

These findings are indicative of an association between SHR and re-hospitalization risk in patients with known ischemic nonobstructive coronary artery disease. Measuring the SHR at the time of hospitalization may therefore help identify at-risk patients. The authors hypothesize that “hyperglycemia may trigger coronary microvascular dysfunction” in these patients leading to poor clinical outcomes.2 Achieving optimal glycemic control should be an important component of management of these patients.

References

1. Pasquale Mone, et al. Stress hyperglycemia drives the risk of hospitalization for chest pain in patients with ischemia and nonobstructive coronary arteries (INOCA). Diabetes Care. 2023 Feb 1;46(2):450-454. doi: 10.2337/dc22-0783.

2. Pasquale Mone, et al. Abstract 15067: Stress hyperglycemia on hospital admission drives the risk of re-hospitalization for chest pain in INOCA patients. Circulation. 2022;146:A15067.