How do doctors choose to prescribe NOACs vs VKAs for stroke prevention?

The choice between nonvitamin K antagonist oral anticoagulants (NOACs) or vitamin K antagonists (VKAs) for stroke prevention appears to be complex and largely heterogenous across different, countries, a new study has found.

In the 24,137 patients whose records were reviewed, NOACs (n=12,395; 51.4 percent; median age, 72.0 years) had been the medication of choice, though not by a big margin over VKAs (n=11,742; 48.6 percent; median age, 71.0 years). Logistic least absolute shrinkage and selection operator (LASSO) regression was performed to determine predictors of NAOC or VKA use.

Prescription trends of NOACs varied greatly across the 35 countries included in the analysis, ranging from 6.1 percent (of all patients who were given anticoagulants) in Thailand to 87.5 percent in Switzerland. Country of enrolment emerged as the strongest predictor of anticoagulants.

Excluding the country variable, the year of enrolment was found to be the next most influential factor, followed by the setting in which patients were enrolled. Notably, the participants’ clinical and demographic characteristics were consistently the least important factors in anticoagulant choice.

In comparison, LASSO revealed that patients presenting to the emergency care (odds ratio [OR], 1.16, 95 percent CI, 1.04–1.30) or outpatient (OR, 1.15, 1.05–1.25) setting were significantly more likely to be prescribed NOACs than VKAs as a first-line treatment for stroke prevention as opposed to patients who had been admitted into the hospital.

Factors that were predictive of NOAC prescriptions included year of enrolment, increasing age and acute coronary syndrome. On the other hand, having moderate-to-severe kidney disease, heart failure and diabetes were significantly associated with VKA prescriptions.