Blood pressure and the effect of calcium enriched milk in humans with normal or mildly elevated blood pressure : methodological considerations : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Physiology at Massey University
The aim of the present study was to assess the influence of three different milk products on blood pressure in patients with mild hypertension who were not under medication or had ceased medication for the trial period under medical supervision. In addition, the effect of calcium on blood pressure was to be explored. The initial objectives of the trial were not met because the trial was stopped due to an adverse coronary event in one volunteer. However, there was sufficient data to reinforce the validity of the methodology, especially the ambulatory blood pressure recording, and to ensure that all other aspects of the trial were achievable. Subjects with elevated blood pressure could be recruited and undergo a series of tests to determine their physical parameters, have blood pressure taken by a variety of methods and on several occasions, and meaningful data obtained. In addition, a small, potentially beneficial, modification could be made to their diet, and the effect of this dietary change monitored by both blood pressure and blood profile changes. These changes were made with minimal disruption to their daily routine, and were generally well-received. The present study confirmed that ambulatory blood pressure monitoring could be conducted with little intrusion into the lives of the subjects. The data obtained from a variety of methods was able to identify those subjects who presented with some of the cluster of factors which characterise Syndrome X. These results, while only from a small sample group, strongly support the use this research methodology to provide an accurate representation of a population subgroup, such as those with elevated blood pressure. In addition, the effect of a dietary intervention on blood pressure and blood lipid profiles can be monitored in free-living subjects.