Identification in post-myocardial infarction patients of significant characteristics that would differentiate between cardiac rehabilitation participants and nonparticipants in a medium sized community hospital

The sample consisted of all male patients who had been discharged with a diagnosis of myocardial infarction from East Tennessee Baptist Hospital between February 1, 1976, and September 1, 1977. Sixty-eight patients (20 who had participated in the Heart Center program and 48 collected who had not) agreed to participate in the study. Data were from the individuals at three times: Time One (hospital admission for myocardial infarction). Time Two (3 months post-myocardial infarction). and Time Three (6 months post-myocardial infarction). The following items of information were obtained when available from hospital charts and physicians' office records: age, number of myocardial infarctions. participation or nonparticipation in Heart Center program, presence of diastolic cigarette smoking, height, weight, systolic blood pressure, blood pressure, presence of angina, presence of diabetes, subsequent myocardial infarctions, electrocardiogram abnormalities, and blood measurements of creatinine phosphokinase, hemoglobin, hematocrit, blood glucose, and lipoproteins. Questionnaires were also sent to the participants.

The data were analyzed by regressing group participation and nonparticipation on sets of the independent variables using multiple linear regression. This was done in order to determine and quantify the best predictor variables differentiating the groups. Chi-square was used on the non-numerical variables. In addition, the groups were compared over time to detect changes and differences in the changes. The responses from the questionnaires were compiled and comparisons made into the between the groups. This information gave some insight work status. patient's present status, subjective feelings, and work status.

The variables from Time One that were most significantly related to eventual participation or nonparticipation represented by a relationship at the 0.01 level of significance were age and alpha (High Density Lipoproteins), beta (Low Density Lipoproteins), and pre-beta (Very Low Density Lipoproteins). Alpha, beta, and pre-beta represented the electrophoretic fractionalization of cholesterol. Phenotype (lipoprotein profile) contributed substantially to the regression model but not at the 0.01 level. R² for the equation was 0.675. A and the variables relationship was also demonstrated between the groups of subsequent myocardial infarctions (subsequent to Time Three up to completion of questionnaire), Q waves in the lateral location, and a level of Q waves in the inferior location. This equation represented 2 significance at 0.0147 with an R² of 0.150.

There were no differences at the 0.01 level between the groups with respect to the non-numerical, indicator variables as demonstrated by 0.10 level or below Chi-square; however, there were differences at the waves in the lateral with respect to Q waves in the inferior location, Q location and CPKII enzyme.

There were no differences in the groups relative to the independent variables from Time One to Time Two and from Time One to Time Three; however, marked differences were present in the groups with respect to return to work and symptoms experienced. According to the questionnaire to work within responses, 71 percent of the participants had returned 6 months of their heart attack whereas this figure was 37 percent for the nonparticipants, Forty-seven percent of the Heart Center group stated they were having no symptoms of pain or shortness of breath; only 15 percent of the nonparticipants stated they were having no symptoms. The Heart Center group had had no subsequent myocardial infarctions whereas the nonparticipants' group had had 6. However, this difference was not significant.

Based on the analysis of the data, that the most it was concluded significant variables differentiating between the groups were age, order, There were alpha (HDL), beta (LDL), and pre-beta (VLDL) in that no significant differences in the groups over time, According to the to work sooner questionnaire responses, the Heart Center group returned and experienced fewer symptoms.