Treatment effectiveness and differential personality responsiveness to a biobehavioral treatment of hypertension in an industrial setting
The effectiveness of relaxation therapy and stress management techniques for lowering blood pressure in essential hypertensives was tested. Twenty-six diagnosed and treated hypertensive employees participated in a ten week group based stress management program. Eighty-five percent of the subjects were on one or more medications. Seventy percent were defined as being well controlled by a criterion of systolic blood pressure being below 140 mm Hg and diastolic blood pressure being below 90 mm Hg. Meetings were conducted once per week during the lunch hour. Subjects also practiced extensively at home. The treated subjects were compared to a control group (N = 22) of hypertensive employees who, like the treated employees, self-monitored blood pressure on a daily basis. Five weeks of blood pressure self-monitoring baseline was taken for both the experimental and control groups. No change in medication regime was undertaken during the course of the training program. All participants were volunteers and had been identified through a company wide blood pressure screening program conducted approximately two months prior to the beginning of this study. The mean systolic blood pressure screening level for the treatment group was 136.23 mm Hg, S.D. = 16.32. The control group mean systolic blood pressure screening level was 135.20 mm Hg, S.D. = 13.46. The treatment group mean diastolic blood pressure screening level was 85.08 mm Hg, S.D. = 8.87. The control group mean diastolic blood pressure screening level was 86.80 mm Hg, S.D. = 7.63. After five weeks of baseline and ten weeks of treatment, the treatment group's mean systolic blood pressure was 126.91 mm Hg, S.D. = 12.53. At this time the mean diastolic blood pressure for the treatment group was 80.69 mm Hg, S.D. = 7.78. After 15 weeks of self-monitoring of blood pressure the control group's mean systolic blood pressure level was 134.64 mm Hg, S.D. = 9.49. The mean diastolic blood pressure for the control group at this time was 86.65 mm Hg, S.D. = 8.57. A repeated measure ANOVA yielded significant effects comparing baseline to treatment of the treatment group for systolic blood pressure (F = 4.87, p<.03) and for diastolic blood pressure (F = 5.38, p<.03). Covariance analyses comparing the treatment and control groups produced similar results. In the treated group, the mean reduction in systolic pressure was 9 mm Hg and in diastolic pressure 4.5 mm Hg from initial screening to treatment. The results suggest that a stress management program can have a significant effect on essential hypertension concurrently controlled on medication. Additionally, the intervention was relatively economical in that it was conducted at the worksite during the lunch hour with a therapist investment time of approximately 1 1/2 hours per subject. No differential response was noted in relation to personality characteristics of the treated subjects.