Randomized Controlled Trial of a Cardiac Rehabilitation of Thai Patients With Myocardial Infarction

Purpose:

This study examined the effects of a self-efficacy enhancement program for the cardiac rehabilitation [SEPCR] on self-efficacy and functional status of Thai patients who had a myocardial infarction.

Methods:

 Study design

A two-group randomized controlled trial with a pretest/posttest design was used to determine the self-efficacy and functional status of Thai patients who have had an MI. Data were collected and analyzed at baseline (on the second day of admission) and again at four weeks after discharge. The study was designed to capture the maximal effect of the SEPCR on self-efficacy and functional status at four weeks, representing the critical time of a decline in functional status while resuming normal functioning.

Ethical considerations

Ethical approval was obtained from the research ethics committees of Mahasarakham Hospital (Approval No. 11/2556). All participants provided written informed consent. The investigation conforms to the provisions of the 1995 Declaration of Helsinki (as revised in Edinburgh 2000).

Participants

Sixty-six hospitalized patients of various ages and both genders were recruited from medical wards during June to December 2013. Eligibility criteria included: consenting patients diagnosed with either an ST-elevation MI (STEMI) or a non-ST-elevation MI (NSTEMI); patients who had received only medical therapy; patients classified as low-risk according to Stratification Algorithm for Risk of Event and patients with at least one family caregiver.

Randomization and blinding

After completing all of the baseline assessments, all eligible consenting participants were randomized to one of two interventions: usual care (control) or the SEPCR plus usual care (experimental). Randomization was performed in permuted blocks of four with a random order of the blocking number. In order to conceal randomization, numbered, sealed, opaque envelopes were prepared prior to participant recruitment by an individual not involved in this study. The researcher used the draw technique to randomly select one of the six types of blocks and then created allocations for each group of four participants until the last participant was enrolled in the study. After being assigned to the intervention, the participants in the control group were blinded to usual care, while the participants in the experimental group were blinded to the SEPCR.

Intervention

Self-efficacy enhancement program for cardiac rehabilitation (SEPCR)

The SEPCR was based on Bandura’s social cognitive theory and was designed to enhance self-efficacy for independent exercise and activities of daily living (ADL) performance through the use of self-efficacy sources (i.e. enactive mastery experience, vicarious experience, verbal persuasion, and physiological and emotional states) and collaboration with a family member who provided support. The SEPCR consisted of three hospitalized sessions, with each lasting about 40 min. Each session began by promoting relaxation with deep breathing and self-massage. The first session addressed motivation-building activities to increase the practices of CR. Each participant was encouraged to share their symptom experience and reinterpretation, and was provided education about MI, walking exercise, performance of daily activities, healthy eating, risk-factor modification, symptom management (i.e. chest pain and stress management), and medication administration by watching a DVD and receiving a booklet. The booklet reinforced the content of the DVD. Knowledge was assessed after completing individual education. The participant was exposed to other patients who had successfully recovered (role model) and engaged in a discussion focused on the role model’s success and strength of ability, and the feasibility of the participant practicing CR. Each participant also set specific short-term and long-term goals that he or she could achieve in a week, and identified specific strategies for how to achieve goals. The second and third sessions emphasized skill training, which included a walking exercise demonstration and practice, heart rate checks and assessments of the rate of perceived exertion, and an energy conservation demonstration and practice. After three sessions, CR was monitored with an exercise and daily activity diary and three telephone counseling sessions (once a week for 3 weeks), each lasting 10–15 min. Each participant had to record and evaluate their walking exercise and performance of daily activities, related to their set goals. The researcher delivered counseling sessions which involved enquiries about experiences of symptoms, followed by the provision of symptom reinterpretation, identifying and overcoming barriers, positive reinforcement, and motivational advice. A review was carried out during the last week of home CR, in which success and progress were evaluated and subsequent goals were set.

Usual care

The participants in the control group underwent medical evaluation and engaged in two sessions of CR during hospitalization. They were trained step-by-step in the structured exercise and performance of daily activities along with the medical regimen. On the day of discharge, they received brief information (i.e. causes of MI and symptoms, medication administration, risk-factor modification) from a doctor, a nurse, and a pharmacist, and they also received a booklet.

Measurement

Functional status was measured using the Duke Activity Status Index (DASI), a self-administered 12-item measure, which comprises four major activity domains: personal care,ambulation, household tasks, sexual function and recreation. Patients were asked if they could perform each of the specified activities, to which they could give a “yes/no” answer. If a patient answered, “yes,” then the item was assigned a weighted score, based on the known metabolic cost of each activity. If a patient indicated “no,” not able to perform an activity, then the weighted score was zero. The potential range of the sum score is 0–58.2, with 0 = worst and 58.2 = best; higher scores indicate better functional capacity. The DASI was translated into Thai by Vibulchai et al. Concurrent, known-group validity has been reported. The Cronbach’s alpha coefficient was 0.76

Self-efficacy was measured using the Maintain Function subscale of the Cardiac Self-efficacy Scale (CSES), a five-item, five-point Likert scale from zero (not at all confident) to four (completely confident). All responses are added to produce raw scores (0–20); higher scores represent higher confidence levels. During its development, the Maintain Function subscale of the CSES was found to have high internal consistency and good convergent and discriminant validity. In this study, Cronbach’s alpha for the Maintain Function subscale of the CSES was 0.87.

Data collection

Patients were provided with explanations regarding the study purpose, study procedures, the content of the questionnaire, the participants’ rights, and the potential benefits and risks of participation in the study. Following the provision of written informed consent, clinical data were collected from the patients’ medical records. The researcher asked eligible participants to complete questionnaires on self-efficacy and functional status during hospitalization. Four weeks after discharge, the participants visited the medical outpatient department where they completed the questionnaires once again. The questionnaires took 15–20 min to complete.

Statistical analysis

Descriptive and inferential statistics (independent t-test and chi-square test) were used to analyze the participants’ baseline demographic and clinical characteristics. An independent t-test was performed to determine differences in the self-efficacy and functional status scores of the experimental and control groups. Statistical significance was set at P < 0.05.

 Results:

 Four weeks after discharge, the experimental group was found to have significantly higher total self-efficacy and functional status scores than the control group. In addition, the experimental group exhibited significantly higher subscale scores on social activity, household tasks, occupation, and exercise self-efficacy than the control group.

Conclusion:

The SEPCR based on Bandura’s social cognitive theory appears to be a useful intervention for CR for Thai patients who have had an MI, and would be a useful supplement to medical care. Healthcare professionals should help patients engage in exercise habits and ADL performance as early as possible in their cardiac recovery.