3 Results
3.1 Study selection and characteristics
A total of 286 records were screened using the aforementioned search
criteria. After excluding 9 duplicates, we further excluded 250 records
based on title and abstract, resulting in 27 studies for full text
review. After the additional exclusion of 19 studies that did not meet
the inclusion criterion (16 studies were one arm or didn’t have a
thorough comparison between the groups of interest and 3 studies had
less than 20 patients in either group17-19), 8 studies
were included in the final meta-analysis7,8,13,20-24(Figure 1). Baseline study characteristics with the MINORS total score
are shown in Table 1. A total of 1390 patients were allocated to two
groups: a DOAC group of 466 patients and a VKA group of 924.
3.2 Outcomes
3.2.1 Days in hospital meta-analysis
5 Studies reported on days in hospital and were included in the
meta-analysis13,20-23. A significantly longer
in-hospital stay was found in the VKA group (SMD= -0.22, 95% CI -0.42
to -0.02, P= .03; Table 2). There was no heterogeneity among the studies
(I2= 0%, 95% CI 0 to 71.8, P= .6). The fixed effects
model was therefore applied.
3.2.2 Posterior epistaxis meta-analysis
6 Studies reported the rates of posterior
epistaxis7,8,13,20,22,23 to be significantly more
common in the VKA group (OR= .39, 95% CI .23 to .68, P= .001; Table 3).
The heterogeneity was low (I2= 16.7%, 95% CI 0 to
61.5, P= .3). The fixed effects model was therefore applied.
3.2.3 Admission rate meta-analysis
With regard to the rate of admission to hospital as a percentage of all
patients seen in the emergency room, data was extracted from 6
studies7,8,20,21,23,24. No statistical significance
between the groups could be found (OR= .76, 95% CI .54 to 1.07, P= .12;
Table 4). The heterogeneity was low to moderate (I2=
46.03%, 95% CI 0 to 78.63, P= .1). The fixed effects model was
therefore applied.
3.2.4 Intervention meta-analysis
7 Studies reported on surgical intervention and/or
embolization7,8,13,20-23. No statistical significance
between the groups could be found (OR= 1.29, 95% CI .63 to 2.66, P=
.38; Table 5). No heterogeneity was detected (I2= 0%,
95% CI 0 to 69.3, P= .5). The fixed effects model was therefore
applied.
3.2.5 Recurrence rate meta-analysis
The recurrence rates were noted in 5
studies7,8,13,21,22. The rates were comparable between
the groups with no statistically significant difference (OR= 1.13, 95%
CI .75 to 1.7, P= .57; Table 6). No heterogeneity was noted
(I2= 0%, 95% CI 0 to 41.03, P= .86) and the fixed
effects model was therefore applied.
3.2.6 Haemoglobin level meta-analysis
The haemoglobin value on admission was reported in 5
studies7,13,20,22,23. No significant differences
between the groups were noted (SMD= - .32, 95% CI - .89 to .28, P= .28;
data not shown). The heterogeneity was high (I2=
81.6%, 95% CI 57.2 to 92.1, P= .0002). The random effects model was
therefore applied.
3.2.7 The need for transfusion meta-analysis
5 Studies reported on the rate of
transfusion8,13,20,22,23. The need for transfusion was
very rare and no statistically significant difference between the groups
was found (OR= 1.34, 95% CI .52 to 3.26, P= .57; data not shown). The
heterogeneity was very low (I2= 0%, 95% CI 0 to
61.96, P= .73). The fixed effects model was therefore applied.
3.3 Publication bias
Publication bias was assessed by funnel plots (Tables 2-6, data for
haemoglobin value and need for transfusion not shown). The plots were
generally symmetrical for all investigated parameters, except for the
haemoglobin value. This suggests a low risk of publication bias for the
investigated criteria.