Analysis Of Resting Blood Pressures Over The Course Of Two In-patient Cardiac Rehabilitation Protocols

Abstract

PURPOSE: To determine if two consecutive cardiac rehab protocols alter resting blood pressures (RBP) in CAD patients and if RBP adjusted for waist circumference (WAIST) remain different with respect to BMI classification. METHODS: Fifty patients with CAD (N=40 males, mean age=62, mean BMI=28; N=10 females, mean age=60, mean BMI=30) underwent RBP assessments at four time-points: the beginning and end of two consecutive 25-day inpatient cardiac rehab stays. Rehab training consisted of endurance and resistance exercises. Height and weight were assessed and BMI was calculated as weight (kg) / height (m) squared. Subjects were assigned to BMI categories (BMICAT) of either "overweight" (OW)(N=20) or "obese" (OB)(N=18) or "normal weight" (NW)(N=12) according to the National Institutes of Health guidelines. Resting systolic (SBP) and diastolic (DBP) blood pressures were taken at each timepoint. Mean arterial pressure (MAP) was estimated as [.3(SBP-DBP)]+DBP. A 3×4 split-plot analysis of variance (ANOVA) with repeats across time was used to determine if participation in cardiac rehab altered RBP. The same statistic with a covariate added (ANCOVA) was used to determine if differences in RBP remained different after adjustment for WAIST. RESULTS: ANOVA showed no treatment effect for cardiac rehab on any pressure at any of the three time-points. Data were collapsed across the time-points and ANCOVA revealed that, after adjustment for WAIST, significant differences in blood pressures among BMICAT remained (P<0.05). CONCLUSIONS: In-patient cardiac rehab does not alter resting blood pressure. After adjustment for body fatness (WAIST), significant differences remain in blood pressure among patients classified according to BMI.Table: least square means p/m SEE, column means with the same letter are not sig. different