The effects of intravenous insulin infusions on early mortality for patients with acute coronary syndromes who present with hyperglycaemia: A matched propensity analysis using data from the MINAP database 2008–2012

BACKGROUND: In acute coronary syndrome, the use of intravenous insulin infusions (IVII) to control hyperglycaemia is based on limited evidence of survival benefit. AIMS: To compare 7 day survival for patients receiving IVII compared with those receiving routine care to control admission hyperglycaemia (>=11 mmol/l) in acute coronary syndrome. METHODS AND RESULTS: We used matched propensity analysis to examine observational data from the MINAP database between 2008 and 2012. We matched 5974 pairs of patients. We separately examined outcomes for ST elevation (STEMI) and non ST segment elevation (NSTEMI) infarctions, and those without known diabetes and those with type 2 diabetes. Survival benefit from the use of IVII was seen only in patients with STEMI not known to have diabetes at admission (adjusted hazard ratio (HR) 0.77 (95% confidence interval (CI) 0.64-0.92), p=0.005). Those with STEMI and existing type 2 diabetes who received IVII showed similar outcomes to routine care (HR 0.99 (95% CI 0.80-1.23), p=0.931). In patients with NSTEMI IVII was associated with significantly worse adjusted 7 day survival outcome than routine care, regardless of diabetes status; for those without known diabetes, HR 1.50 (95% CI 1.04-2.16), p=0.029, and for those with type 2 diabetes, HR 1.35 (95% CI 1.08-1.70), p=0.010. CONCLUSION: As used in current clinical practice to treat hyperglycaemia in acute coronary syndromes, IVII appears to be of benefit only for patients with STEMI who are not known to have diabetes. IVII is associated with adverse early outcomes in patients with NSTEMI.