Study population
To establish a recruitment database, a list of all admissions to a single metropolitan tertiary referral hospital in Sydney Australia, with an ACS during a 10 month period, was obtained using diagnostic related codes [
24] for UA (F72A, F72B), MI (F41A, F41B, F60A, F60B) and chest pain (F74Z). For all admitted patients, the hospital medical records were reviewed to determine secondary prevention eligibility. Reasons for ineligibility included geography (living outside a 20 km radius of the hospital), insufficient English language to provide informed consent, congestive heart failure, the presence of a severe co-morbidity (eg, end stage renal disease, Parkinson's disease, cancer) and death.
Inclusion criteria for the randomised conventional care and modular groups were:
No previous attendance at a formal cardiac rehabilitation program including those who refused the initial invitation to participate and those who failed to attend the initial cardiac rehabilitation assessment.
Diagnosis of ACS in the six months prior to recruitment.
Ability to understand sufficient English to give written and informed consent.
Inclusion criteria for non-randomised standard rehabilitation group were:
Commencing attendance at the CRGH cardiac rehabilitation program during the data collection period of the study.
Diagnosis of ACS in the six months prior to recruitment.
Ability to understand sufficient English to give written and informed consent.
Exclusion criteria were the same for all three groups in the study and were:
Clinical diagnosis of uncompensated, severe cardiac failure (Class IV).
Uncontrolled arrhythmia or angina
Severe or symptomatic aortic stenosis
Persistent hypotension (SBP < 90 mmHg)
Clinical diagnosis of a severe co-existing medical condition that would prevent participation (eg, dementia, a rapidly deteriorating terminal illness or severe or active rheumatoid arthritis)
Once the database of eligible patients is constructed, all patients will be contacted by mail and telephone and asked to volunteer for research investigating heart disease risk factors. Recruitment mail-outs will be conducted in batches of 30 to enable staggered recruitment over approximately six months. Patients will be contacted within two weeks of the mail-out to establish whether they would be prepared to volunteer.
Outcome measures
Assessments will be conducted in the hospital consulting rooms or in the participant's home, if they are unable to travel to the hospital. Demographic, subjective and objective information will be obtained during face-to-face assessments at baseline, three and 12 months. Information will include past history, nature of ACS, family history, age, medications and dose, presence of other cardiovascular disease and the nature and date of any revascularisation. In addition, contact details for each participant, their general practitioner and their cardiologist will be documented.
At three and 12 month follow-up, all baseline measures will be repeated during face-to-face assessments by a researcher blinded to group allocation. Additional collected information will include – details of unplanned hospital admissions, medications and doses along with details of any health interventions undertaken by the participant pertaining to their heart health, such as visits to the GP and attendance at community programs. For participants in the standard rehabilitation group, details of participation in the cardiac rehabilitation program will also be recorded such as duration and attendance at exercise and education sessions.
Modifiable risk factors to be measured are serum cholesterol, BP, smoking status, physical activity, overweight and depression. Lipids and substrates will be measured on a fasting blood sample within two weeks of assessment date. Participants will be referred to local pathology clinics by their primary care doctor and will visit the clinics by their own arrangement. Blood samples will be analysed for determination of total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and triglycerides (TG). Repeat blood tests will be carried out at the same pathology clinic wherever possible.
Resting BP will be measured from the brachial artery using an Omron digital automatic BP (Omron Healthcare Co Ltd Model M5, Japan). The automatic BP monitor will be calibrated against a mercury sphygmomanometer prior to study commencement and has been demonstrated to be accurate. The Omron M6 is accurate for BP to within 3 mmHg [
26] and fulfills the recommendation criteria of the international protocol when tested against a mercury sphygmomanometer for diastolic and systolic BP readings [
27]. For measurement, appropriate cuff size will be selected, each participant will be seated with the right arm supported and two consecutive blood pressure readings will be collected with one minute interval according to previously published guidelines [
28].
Smoking status will be initially assessed by analysis of carbon monoxide (CO) levels using a hand-held breath analyzer or CO meter (Bedfont micro smokerlyzer, Scientific Ltd, England) using new mouthpieces (Airmet Scientific EC50MP500, Victoria Australia) for each participant, for infection control purposes. Participants will be expected to blow into the mouthpiece for the 15 seconds and the result are to be recorded in parts per million (ppm). The criteria for recent, within the past 24 hours, smoking will be an expired CO greater than 5 ppm [
29]. Smoking status will be confirmed with self report to identify participants who concealed their true smoking status. Participants will be asked whether they had ever smoked, how long since they started or stopped and if they smoked, what is/was the average number of cigarettes smoked per day.
Physical activity levels will be assessed using the International Physical Activity Questionnaire (IPAQ) score [
30]. The short, last-seven-days, self-administered format (last revised August 2002) comprises seven questions that seek information about the duration and frequency of vigorous and moderate physical activity as well as rest and walking in the past seven days. The IPAQ was developed as an international measure of physical activity, for use in adults, and has been tested for reliability and validity across 12 countries [
31]. For final scoring, responses are divided into three categories, MET-minutes per week, average time spent sitting per day and a categorical level of physical activity. The categorical score is further divided into three levels – insufficiently active, sufficient activity and highly active.
For assessment of depressive mood, the Cardiac Depression Scale (CDS) score will be used [
32]. The CDS was developed from the responses of cardiac outpatients and comprises 26 items with subscales relating to sleep, uncertainty, mood, cognition, hopelessness and inactivity. Some items are scored in reverse and raw scores are used for analysis where higher scores indicate depressed mood and a score of greater than 90 represents depressive mood. When assessed for test-retest reliability over two weeks scores were 64.9 ± 23.3 (mean ± SD) and 63.1 ± 23.0 with correlation coefficient of 0.86 and score difference of -1.9 ± 12.2 (mean ± SD). Permission has been obtained to administer the CDS from Professor Hare, Department of Cardiology (Austin & Repatriation Medical Centre, Australia).
For assessment of overweight, body mass index (BMI) will be calculated using the standard equation (BMI = weight kg/height m
2). Each participant's body weight will be measured when lightly clothed and in bare feet using digital scales (Tanita EB727, Australia) to the nearest 0.1 kg. Height will be measured without shoes using a standiometer (Stature Meter 2 m 1013522, Livingston International Pty Ltd, NSW Australia) to the nearest 0.5 cm and according to best anthropometic practice [
33].
Health related quality of life (HRQOL) will be assessed using the SF36 health survey [
34], [
35]. The SF36 comprises 11 items that ask for the participant's views about their health, how they feel and whether they are able to perform certain activities and has been tested for reliability and validity [
34], [
35]. A license has been obtained to use the SF36 for data collection from 300 patients on three occasions per participant (License number F1-052203-13860). SF36 scores will be coded, summed and transformed onto a scale from 0 (worst possible health) to 100 (best possible health) using the method described in the user manual [
36].
Relative cardiac risk will be calculated using the LIPID score which was developed for use in secondary prevention [
37]. An individual's risk score calculation involves aggregating risk point estimates corresponding to the patient's risk factor profile. Aggregate scores provide an indication of the level of risk for a future ACS. The scores are divided as low risk (≤ 4), medium risk (5–6), high risk (7–9) and very high risk (≥ 10) [
37]. Further, each participants number of modifiable risk factors will be calculated using the cut points; TC > 4.0 mmol/L, SBP ≥ 140 mmHg, current smoking, physical inactivity using the categorical IPAQ score, BMI ≥ 30 kg/m
2, known diabetes and a CDS score ≥ 90 for depression.
Each participant's knowledge of their own cardiovascular risk factors will also be assessed at baseline, three and 12 months. Participants will be asked if they can state any of their own modifiable risk factors for heart disease and the number stated will be compared to the each individual's actual number of modifiable risk factors. Participants will then be asked if they are able to state the Australian recommended targets for total cholesterol, BP, physical activity and whether or not smoking is recommended for people with CHD.
Procedure
Conventional care group
Participants randomly allocated to the conventional care group will continue to manage their heart health as directed by their primary care doctor or by their own cognisance. This group will not receive any additional intervention as a result of participation in the study. However, they will be contacted by telephone 2–3 weeks after baseline assessment to confirm their three month assessment appointment. In addition, each participant's general practitioner (GP) and cardiologist will be mailed a courtesy letter following baseline assessment and a risk factor summary with recommendations for discussion regarding long-term risk factor management following the final 12 month assessment.
Modular group
Participants randomly allocated to the modular group will manage their heart health by participation in modular guided self-choice management of heart disease. That is, participants will participate in risk factor modules of their choice, with the exception of the mandatory blood cholesterol module, strive to achieve mutually-agreed goals and make choices about risk factor reduction interventions based on their own circumstances. Following baseline assessment, the consultation will be extended by approximately 30 minutes for selection of modules, goal setting and shared decision making about risk factor interventions.
The risk factor modules consist of cholesterol-lowering, BP management, smoking cessation and physical activity. All participants will participate in the cholesterol-lowering module and where applicable, participants can also choose up to two other modules depending on their individual risk factor assessment and personal preference. Therefore, all participants will participate in a minimum of one risk factor module and a maximum of three modules at any one time.
The mandatory cholesterol-lowering module involves pharmacological intervention in consultation with the primary care doctor as well as education and empowerment through information and support about individual and nationally recommended cholesterol levels. The three optional modules involve choice of intervention including; following medical advice; participating in a structured program (individual or group); participating in a home program; or self-help. All risk factor modules will be resourced and delivered separately among the primary care doctor, the local area health service, the local community and the participant. Participants in the modular group will receive a resource package including appropriate information leaflets which contain guidelines and information about the module and contact information for community heart health programs. The leaflets have been developed and pilot tested, for validity, by health professionals and consumers.
For each risk factor module, a three month objective goal will be set based on shared decision-making. The mutually-agreed goal will be based on the each participant's risk factor profile, social factors, commitments and personal preference. Participants will also asked to rate their confidence in achieving the set goal on a visual analogue scale from 1–10. Each risk factor baseline level, mutually agreed goal, time frame and confidence rating will be recorded on the information leaflet.
All participants in the modular group will also be "coached" using a previously published model [
38]. The coaching model is a five stage cyclic process and involves assessing understanding, providing education, assertiveness training and reassessment. In this study, the first coaching session will be conducted during the initial face-to-face shared decision making, goal setting session. Participants will then be coached over the telephone on up to four further occasions, depending on goal achievement, during the following three months depending on need. Once each risk factor goal is achieved, no further coaching is required. All coaching will be conducted by a researcher who has been trained by the original coach study coordinator. During each coaching session individual's knowledge of their risk factors and personal goals will be identified and participation in the module will be established and recorded.
Communication between the study coordinator, the participant and health professionals involved and community services will be facilitated where possible. Each participant will also be encouraged to communicate openly about their goals and modules with their local doctor and cardiologist. During the course of the study, participants identified as being clinically depressed, according to their CDS, are to be offered an appointment with a clinical psychologist specialising in heart disease. For each participant, their GP and cardiologist will be sent a comprehensive letter outlining the participant's risk factors, goals and chosen modules. Following the final 12 month assessment, all participants and their doctors will also receive a cardiac risk factor summary and recommendations for discussion regarding long term risk factor management. By facilitating communication, it is anticipated that each participant receives a coordinated multidisciplinary approach to their own risk factor management based on need and situation.
Standard rehabilitation group
Participants who volunteer for the standard rehabilitation group will attend the hospital-based outpatient cardiac rehabilitation program. This rehabilitation program includes twice weekly group hospital-based exercise classes for six weeks and weekly education sessions. The exercise program is supervised by a clinical nurse specialist and a physiotherapist. The exercise sessions are generally of 45 minutes duration and include a 10 minute warm up and cool down and approximately 30 minutes of cardiovascular and resistance exercise stations. These stations include leg press, treadmill walking, stair climbing, knee extension weights, stationary cycling and gentle upper limb weights. Each station is conducted for 3 minutes and patients rotate around the room from station to station with a 2 minute rest between stations. Exercise intensity is based on rating of perceived exertion (RPE) at a moderate level (3–4) on the modified RPE scale [
39].
The education sessions, include general information about heart disease and associated risk factors, two sessions by a pharmacist about medications, two sessions about dietary advice by dietitian (one theoretical and one practical session), two sessions from a clinical psychologist and one session about exercise by a physiotherapist. Participants will be encouraged to attend two exercise sessions per week and all the educational sessions if possible. There is no transport available for travel to and from the sessions however, parking is available in the hospital car-park at each patient's expense. Similar to the conventional care group, the standard rehabilitation group will not receive any additional intervention as a result of participation in the study. However, all participants will be contacted by telephone 2–3 weeks after baseline assessment to confirm their three month appointment. In addition, each participant's GP and cardiologist will be mailed a courtesy letter following baseline assessment and a risk factor summary with recommendations for discussion regarding long term risk factor management following the final 12 month assessment.