Background

Novel oral anticoagulants (NOACs) have been shown to be at least as good as warfarin for preventing stroke or transient ischemic attack in patients with atrial fibrillation, yet diffusion of these therapies and patterns of use among atrial fibrillation patients with ischemic stroke and transient ischemic attack have not been well characterized.

Methods and results

Using data from Get With The Guidelines-Stroke, we identified a cohort of 61 655 atrial fibrillation patients with ischemic stroke or transient ischemic attack hospitalized between October 2010 and September 2012 and discharged on warfarin or NOAC (either dabigatran or rivaroxaban). Multivariable logistic regression was used to identify factors associated with NOAC versus warfarin therapy. In our study population, warfarin was prescribed to 88.9%, dabigatran to 9.6%, and rivaroxaban to 1.5%. NOAC use increased from 0.04% to a 16% to 17% plateau during the study period, although anticoagulation rates among eligible patients did not change appreciably (93.7% versus 94.1% from first quarter 2011 to second quarter 2012), suggesting a trend of switching from warfarin to NOACs rather than increased rates of anticoagulation among eligible patients. Several bleeding risk factors and CHA2DS2-VASc scores were lower among those discharged on NOAC versus warfarin therapy (47.9% versus 40.9% with CHA2DS2-VASc ≤5, P<0.001 for difference in CHA2DS2-VASc).

Conclusions

NOACs have had modest but growing uptake over time among atrial fibrillation patients hospitalized with stroke or transient ischemic attack and are prescribed to patients with lower stroke risk compared with warfarin.

Diabetes mellitus, heart failure (HF), and chronic kidney disease are common comorbidities, but overall use and safety of antihyperglycemic medications (AHMs) among patients with these comorbidities are poorly understood. Using Get With the Guidelines-Heart Failure and linked Medicare Part D data, we assessed AHM use within 90 days of hospital discharge among HF patients with diabetes mellitus discharged from Get With the Guidelines-Heart Failure hospitals between January 1, 2006, and October 1, 2011. We further summarized use by renal function and assessed renal contraindicated AHM use for patients with estimated glomerular filtration rate <30 mL/min/1.73m(2). Among 8791 patients meeting inclusion criteria, the median age was 77 (interquartile range 71-83), 62.3% were female, median body mass index was 29.7 (interquartile range 25.5-35.3), median hemoglobin A1c was 6.8 (interquartile range 6.2-7.8), and 34% had ejection fraction <40%. 74.9% of patients filled a prescription for an AHM, with insulin (39.5%), sulfonylureas (32.4%), and metformin (17%) being the most commonly used AHMs. Insulin use was higher and sulfonylurea/metformin use was lower among patients with lower renal function classes. Among 1512 patients with estimated glomerular filtration rate <30 mL/min/1.73m(2), 35.4% filled prescriptions for renal contraindicated AHMs per prescribing information, though there was a trend toward lower renal contraindicated AHM use over time (Cochran-Mantel-Haenszel row-mean score test P=0.048). Although use of other AHMs was low overall, thiazolidinediones were used in 6.6% of HF patients, and dipeptidyl peptidase-4 inhibitors were used in 5.1%, with trends for decreasing thiazolidinedione use and increased dipeptidyl peptidase-4 inhibitor use over time (P<0.001). Treatment of diabetes mellitus in patients with HF and chronic kidney disease is complex, and these patients are commonly treated with renal contraindicated AHMs, including over 6% receiving a thiazolidinedione, despite known concerns regarding HF. More research regarding safety and efficacy of various AHMs among HF patients is needed.