140
I. E. Højskov et al.
Table II. Mean difference in outcome and odds ratio between
experimental group and control group
n
Estimate
Mean (95% CI)
310 16.2 (–13.0; 45.4) 0.27 119.8
Secondary outcomes
SF-12 mental
SF-12 physical
Pittsburgh Sleep QI
Örebro MSQ
Sit-To-Stand test
HADS anxiety
HADS depression 310
310
310
310
310
310
310 0.43
0.49
0.12
0.12
0.13
0.20
0.34 11.8
10.2
4.6
10.9
5.0
4.0
3.8
Binary outcomes
HADS anxiety (8+)
HADS depression (8+)
HeartQol (> median)
HeartQol global
HeartQol emotional
1.18 (–1.74; 4.09)
–0.82 (–3.18; 1.54)
–0.91 (–2.06; 0.23)
–1.92 (–4.34; 0.51)
1.09 (–0.34; 2.52)
–0.59 (–1.50; 0.32)
–0.43 (–1.33; 0.46)
OR (95% CI)
310 0.62 (0.29; 1.29)
310 0.46 (0.22; 0.97) 0.20
0.04
310 0.78 (0.45; 1.35)
310 0.93 (0.42; 2.09) 0.37
0.86
0.14
0.10
–0.08
–0.20
–0.18
0.22
–0.15
–0.11
Table III. HADS-anxiety and HADS-depression in experimental
and control groups
n
Group
HADS anxiety
Cohen’s d
Effect size Cohen’s d: 0.20 = small; 0.50 = medium; 0.80 = large.
SD: standard deviation; MWT Minute Walk Test; QI: Quality Index: HADS: Hospital
Anxiety and Depression Scale; MSQ: Musculoskeletal Screening Questionnaire;
CI: Confidence intervals.
Secondary
outcomes
p-value SD
Primary outcomes
6-MWT
310 Experimental
Control
HADS depression 310 Experimental
Control
Admission Discharge 4 weeks after
Mean (SD) Mean (SD) surgery
5.4
6.0
4.0
3.9
(4.3)
(4.5)
(3.5)
(3.5)
5.7 (4.0)
5.8.(4.3)
5.8 (3.7)
5.7 (4.1)
3.5
4.3
3.7
4.3
(3.4)
(3.7)
(3.2)
(3.7)
HADS: Hospital Anxiety and Depression Scale; SD: standard deviation.
the sessions. The patients participated in 65% (median
68) of the training programme during admission and
54% (median 63) after discharge.
All participants in the experimental group participa-
ted in the psycho-educational intervention, of whom
115/152 (76%) attended all 4 consultations. Regarding
mindfulness 91/152 (60%) participated in the introduc-
tion given as part of the psycho-educational consulta-
tion. Of these, 2 patients (2%) used the mindfulness
toolbox exercises on ≥ 75% of the following days in
hospital, 10 (11%) on 50–74% of the days and 79
(86%) used them rarely or not at all.
Per-protocol analysis
Per-protocol analysis was performed on patients who
completed more than 50% of the exercise training
programme in and out of hospital and the psycho-
educational consultations (n = 51 (34%)). There was a
difference between the experimental and control group
on the 6MWT as primary outcome (41.1 m (95% CI
8.0–74.3 m), p = 0.02) and on 1 of the secondary out-
comes, the Sit-To-Stand test (1.87 repetitions (95% CI
0.04–3.70 repetitions), p = 0.046) 4 weeks after surgery.
These differences corresponded with a Cohen’s d of
www.medicaljournals.se/jrm
Table IV Results of per-protocol. The estimates are the mean
difference in outcome and odds ratio between experimental and
control groups
n Estimate
Mean (95% CI) p-value Cohen’s d
6MWT 209 41.1 (8.0; 74.3) 0.02
Secondary outcomes
SF-12 mental
SF-12 physical
Pittsburgh Sleep QI
Örebro MSQ
Sit-To-Stand test 209
209
209
209
209 1.84 (–1.80; 5.49)
–1.50 (–4.69; 1.70)
–1.49 (–3.02; 0.04)
–3.54 (–6.92; –0.17)
1.87 (0.04; 3.70) 0.32
0.36
0.06
0.04
0.046
Binary outcomes
HADS anxiety (8+)
HADS depression (8+) 209
209 OR (95% CI)
0.56 (0.20; 1.52)
0.46 (0.17; 1.27) 0.25
0.13
HeartQol (> median)
HeartQol global
HeartQol physical
HeartQol emotional 209
209
209 0.76 (0.36; 1.61)
0.70 (0.34; 1.41)
0.87 (0.42; 1.82) 0.48
0.32
0.72
Primary outcome
0.40
0.17
–0.16
–0.31
–0.34
0.36
MWT Minute Walk Test; QI: Quality Index: HADS: Hospital Anxiety and Depression
Scale; MSQ: Musculoskeletal Screening Questionnaire; CI: Confidence intervals.
0.40 and 0.36, respectively (Table IV). The remaining
secondary outcomes, showed no significant differences.
Safety
One serious adverse event was reported at baseline in
the experimental group after administering the 6MWT.
The participant had 2 episodes of ventricular tachycar-
dia after ending the 6MWT. The event was evaluated
to be independent of the 6MWT. There were no serious
adverse events in the control group.
DISCUSSION
To the best of our knowledge, this is the largest ran-
domized controlled trial to examine the effect of a com-
prehensive early rehabilitation programme including
a physical and a psychological component in patients
who have undergone CABG surgery. The intervention
appeared safe, with only one serious event, which was
not related to the trial. The difference between the
experimental group and control group for 6MWT was
statistically non-significant and only a small clinical
effect was indicated by Cohens’ d.
The secondary outcomes showed no difference bet-
ween groups, except a potential difference in favour of
intervention with regard to HADS-D. The intervention
might have had a beneficial effect on depressive symp-
toms. However, it is a secondary outcome and the result
should be interpreted with caution. Data from HADS
was dichotomized, which produces a risk of reducing the
complexity. When looking at the mean scores, there is a
0.6-point difference between the groups in favour of the
intervention group. Symptoms of depression compared
with anxiety are more prevalent in patients undergo-