Preference for direct oral anticoagulants in patients treated with vitamin K antagonists for venous thromboembolism

BACKGROUND

Direct oral anticoagulants (DOACs) are an alternative for vitamin K antagonists (VKA) in the treatment and prevention of venous thromboembolism (VTE). Patient preferences for treatment options have not been extensively explored.

METHODS

A random sample of 200 patients was obtained from those treated with VKA for deep vein thrombosis, pulmonary embolism or both at the Thrombosis Service Amsterdam. Preference for DOACs relative to VKA was assessed using a treatment trade-off technique administered as a questionnaire sent to all patients. The trade-off consisted of four consecutive scenarios: 1 (no need for laboratory control), 2 (decreased bleeding risk), 3 (less interactions with food and other drugs), 4 (higher efficacy).

RESULTS

The response rate was 68%. In scenario 1, 36% of patients would switch to a DOAC. This proportion rises to 57% (odds ratio [OR] 2.3; 95% confidence interval [CI] 1.6-3.3) for scenario 2. Scenario 3 resulted in 64% of patients preferring a DOAC (OR 3.2; 95%CI 2.2-4.6). The advantage of greater efficacy did not result in a noteworthy change in the preference. Patients who were less satisfied with their current treatment, who were younger and those with higher education were more likely to prefer a DOAC over a VKA. The variables gender, treatment duration, and type of VKA were not significantly associated with DOAC preference.

CONCLUSION

Almost two-thirds of patients preferred DOACs over VKA. Patients considered the lack of regular laboratory monitoring, the lower risk of serious bleeding and less interactions with food and other drugs the most important arguments to switch to a DOAC.

Effects of six APOA5 variants, identified in patients with severe hypertriglyceridemia, on in vitro lipoprotein lipase activity and receptor binding

OBJECTIVE

The purpose of this study was to identify rare APOA5 variants in 130 severe hypertriglyceridemic patients by sequencing, and to test their functionality, since no patient recall was possible.

METHODS AND RESULTS

We studied the impact in vitro on LPL activity and receptor binding of 3 novel heterozygous variants, apoAV-E255G, -G271C, and -H321L, together with the previously reported -G185C, -Q139X, -Q148X, and a novel construct -Delta139 to 147. Using VLDL as a TG-source, compared to wild type, apoAV-G255, -L321 and -C185 showed reduced LPL activation (-25% [P=0.005], -36% [P<0.0001], and -23% [P=0.02]), respectively). ApoAV-C271, -X139, -X148, and Delta139 to 147 had little affect on LPL activity, but apoAV-X139, -X148, and -C271 showed no binding to LDL-family receptors, LR8 or LRP1. Although the G271C proband carried no LPL and APOC2 mutations, the H321L carrier was heterozygous for LPL P207L. The E255G carrier was homozygous for LPL W86G, yet only experienced severe hypertriglyceridemia when pregnant.

CONCLUSIONS

The in vitro determined function of these apoAV variants only partly explains the high TG levels seen in carriers. Their occurrence in the homozygous state, coinheritance of LPL variants or common APOA5 TG-raising variant in trans, appears to be essential for their phenotypic expression.