Associations between adherence to DOACs and baseline characteristics, side effects, side effect burden and beliefs about DOAC use
For all MARS-5 scores (irrespective of the cut-off value) an association was found between adherence and both side effects and side effect burden (table 5, results displayed for primary MARS-5 cut-off value only). Non-adherent patients reported significantly more side effects and experience a higher side effect burden regardless of the cut-off value. Furthermore, an association was found between question 11 and adherence: non-adherent patients more often believed that DOACs have unpleasant side effects (table 5).
For the primary cut-off MARS value, no associations were found between patients’ beliefs about DOAC use and adherence for both necessity scores, concern scores, differential and subtypes. Interestingly, all non-adherent patients scored high on necessity.
Patients that believe DOACs have unpleasant side effects (BMQ question 11) reported, as was to be expected, significantly more side effects and experienced a higher side effect burden. Using a regression model to check for correlations between side effects and beliefs we found an association between bleedings and a negative attitude towards DOAC use.
For the primary MARS-5 cut-off value no associations were found between patients’ adherence to DOACs and either gender, DOAC or dosing regimen (once or twice a day intake). Interestingly, although there is no statistical significance, all non-adherent patients (9%) used their DOAC for the indication atrial fibrillation (see appendix).
Table 5. Associations between adherence to DOACs and beliefs about DOAC use for primary MARS-5 cut-off value