Cardiovascular medication in relation to renal function after coronary artery bypass surgery

Guidelines for recommended medication use for the secondary prevention of coronary heart disease are exceedingly important in patients with chronic kidney disease. Despite a high risk for recurrent cardiovascular events, these patients are less likely to use evidence-based recommended medications. The objective of the current study was to analyze the association between renal function and guideline-recommended drug therapy in patients with coronary heart disease.

In this nationwide population-based cohort study, we included 12,332 patients with established coronary heart disease who underwent primary isolated coronary artery bypass grafting in Sweden between 2005 and 2008. Medication use was retrieved from the national Prescribed Drug Register.

During the first year after coronary surgery, 94% of patients had at least two dispensed prescriptions for an antiplatelet agent, 68% for an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker, 92% for a beta-blocker, and 93% for a statin. Only 57% of all patients had prescriptions for all four medication classes. Reduced renal function (estimated glomerular filtration rate (eGFR) of 30 to 45 mL/min per 1.73 m(2) and <30 mL/min per 1.73 m(2)) was significantly associated with a lower use of all four medication classes (adjusted risk ratio 0.89, 95% confidence interval 0.82 to 0.98; and adjusted risk ratio 0.75, 95% confidence interval 0.62 to 0.90, respectively) as compared to normal renal function (eGFR >60 mL/min per 1.73 m(2)).

In patients with established coronary heart disease, moderate to severe renal dysfunction was associated with significantly lower use of guideline-recommend medications as compared to normal renal function.