Delay in time to receipt of thrombolytic medication among Medicare patients with kidney disease.

Background: Patients with kidney disease and acute myocardial infarction (AMI) receive standard therapy, including thrombolytic medication, less frequently than patients with normal kidney function. Our goal is to identify potential differences in thrombolytic medication delays and thrombolytic-associated bleeding events by severity of kidney disease.

Methods: This is a retrospective cohort analysis of Cooperative Cardiovascular Project data for all Medicare patients with AMI from 4,601 hospitals. Outcome measures included time to administration of thrombolytic medication censored at 6 hours and bleeding events.

Results: Of 109,169 patients (mean age, 77.4 years; 50.6% women), 13.9% received thrombolysis therapy. Average time to thrombolytic therapy was longer in patients with worse kidney function. Adjusted hazard ratios for minutes to thrombolytic therapy were 0.83 (95% confidence interval [CI], 0.79 to 0.87) for patients with a serum creatinine level of 1.6 to 2.0 mg/dL (141 to 177 micromol/L) and 0.58 (95% CI, 0.53 to 0.63) for patients with a creatinine level greater than 2.0 mg/dL (>177 micromol/L) or on dialysis therapy compared with those with normal kidney function. Odds ratios for bleeding events in patients administered thrombolytics versus those who were not decreased with worse kidney function: adjusted odds ratios, 2.28 (95% CI, 2.16 to 2.42) in patients with normal kidney function and 1.84 (95% CI, 1.09 to 3.10) in dialysis patients.

Conclusion: Patients with worse kidney function experienced treatment delays, but were not at greater risk for thrombolysis-associated excess bleeding events. Physician concerns of thrombolytic-associated bleeding may not be sufficient reason to delay the administration of thrombolytic medication.