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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 32, No 2, March/April 2021
AFRICA
71
has shown promising results in the secondary prevention of
CAD, reduction in adverse cardiac outcomes and depression,
as well as improvement in QOL.
24-28
In contrast to the developed
world, there are few data from developing countries regarding
the prevalence of depression and the effect of lifestyle changes
on depression among patients with CAD.
21-23
In a recent study,
Ranjith
et al
. analysed incidence of depression among MI
patients in South Africa and reported a prevalence of 49.0%
29
To the best of our knowledge, no study has compared the
effects of LSM on incidence of depression among patients who
undergo coronary artery bypass graft surgery (CABG) versus
percutaneous coronary intervention (PCI). These two modalities
of therapy differ greatly in terms of injury severity score,metabolic
responses, convalescence time and prognosis.
30,31
Furthermore,
studies have shown a causal relationship between depression and
post-infarction inflammatory and neurohormonal changes.
32-38
Therefore we hypothesised that the prevalence of depression
and response to LSM would differ between the two groups. In
this study we analysed the prevalence of depression among MI
patients after revascularisation and examined the effect of LSM
on incidence of depression between CABG and PCI groups.
Methods
The risk-factor profile, depression characteristics and physical
activity (PA) profile were prospectively examined in 100
consecutive participants undergoing coronary revascularisation
over a 15-month period (January 2017 to May 2018). The
study was conducted in the Department of Cardiology and
Cardiothoracic Surgery at Inkosi Albert Luthuli Central
Hospital (IALCH), Durban, South Africa.
After informed written consent was obtained, patients who
met the inclusion criteria were enrolled within two to four
weeks after revascularisation. Approval was obtained from the
Biomedical Research Ethics Committee (BREC/443/16) of the
University of KwaZulu-Natal before starting the study.
Demographic data, anthropometric measurements, vital
signs and other clinical data, as well as blood samples, were
obtained from the patients at the beginning of the study and
thereafter the interview was performed. During the interview,
the Beck depression inventory-II (BDI-II) and Goldin leisure-
time exercise (GLTE) questionnaires were administered by the
researcher (AA) to determine depression status and level of PA.
The GLTE questionnaire is a validated and reliable
questionnaire that is used to assess the level of PA.
39
Briefly,
the patients indicate the number of times they engage in mild,
moderate or strenuous exercise for more than 15 minutes within
a week. The level of PA is categorised as: ‘sufficiently active’
(≥ 24 units/week), ‘moderately active’ (14–23 units/week), and
‘insufficiently active’ (< 14 units/week).
39
For strenuous PA, the GLTE questionnaire demonstrated
moderate-to-strong associations with measured indices of PA,
particularly maximal oxygen consumption determinations
(VO
2max
), and percentage body fat by hydrostatic weighing
(% BF), but a lesser degree of association with the Caltrac
accelerometer (CALTRAC) readings. For moderate PA, it was
modestly correlated with the above measures, but for mild PA
it showed less association with these measures. By and large, it
gives a reliable and fairly accurate assessment of PA.
40
The BDI-II is a simple, reliable and validated 21-item
questionnaire, rated on a four-point scale (0–3).
41
It is one of the
most widely used psychometric instruments in both research and
clinical practice for assessing depression.
42
Based on the total
score obtained, a patient is classified as normal (1–10), having
mild mood disturbance (11–16), borderline depression (17–20),
moderate depression (21–30), severe depression (31–40), and
extreme depression (> 40).
41
The BDI-II adequately corresponds
to the
Diagnostic and Statistical Manual of Mental Disorders
(DSM-IV) criteria and has high reliability and validity.
Based on available psychometric evidence, the BDI-II is
considered a cost-effective questionnaire for measuring the
severity of depression, with broad applicability for research
and clinical practice. Although the questionnaire was originally
designed to measure the severity of depression, existing evidence
shows that the BDI-II can be effectively used to screen for
major depression with a sensitivity of more than 70%. Its major
shortcoming is variability of the cut-off score to screen for
depression according to the type of sample. Non-clinical samples
displayed the lowest range of cut-off points (10–16) to detect
major depression, medical samples had an intermediate cut-off
point (7–20), and psychiatric samples had the highest cut-off
point (19–31). As a self-report measure, there may be reporting
bias since the educational level attained, status and gender may
affect the respondent’s response.
41,42
Eligible patients were enrolled in a supervised exercise-based
LSM programme and after a few sessions, an individualised
aerobic exercise regimen was prescribed based on the standard
guidelines.
43-45
Psychological counselling, smoking cessation and
dietary advice were given as well. At the time of discharge, a
referral letter and written instructions about the individualised
LSM were given to the patients and they were advised to
continue the programme at home. The written instructions
included how to monitor the level of exertion manually using
their heart rate and the Borg’s rating of physical exertion at
home. Studies have shown that home-based LSM is safe and not
inferior to centre-based LSM.
46-48
Patients continued the LSM at home, with a monthly follow
up at their community clinics. After a 12-week period, the
patients underwent a final assessment by the researcher (AA). At
the final visit, anthropometric measurement, vital signs, blood
samples and clinical evaluation were repeated and documented.
The BDI-II and GLTE questionnaires were re-administered and
the results were documented.
Inclusion criteria were male or female eligible adult patients
over the age of 18 years with a documented acute MI who
underwent CABG or PCI in IALCH within the period of
the study and consented to participate in the study. Exclusion
criteria were any patient with a terminal illness or debilitating
co-morbidity, such as incapacitating cerebrovascular accident
(CVA), severe arthritis and other severe diseases, which would
preclude moderate physical activity.
The primary outcome was depression status before and
after LSM as assessed using the BDI-II questionnaire. The
secondary outcome was an improvement in physical function
and endurance, which is reflected by changes in the level of PA.
Statistical analysis
Data analysis was conducted using SPSS version 25. The
demographic, social and clinical characteristics of the patients