Autonomic and Immuno-Vascular Mechanisms of Antihypertensive Effects of Tai Chi
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Hypertension
- Sponsor
- University of California, San Diego
- Enrollment
- 250
- Primary Endpoint
- Blood Pressure
- Last Updated
- 4 years ago
Overview
Brief Summary
Over 30% of American adults have hypertension (HTN) (high blood pressure), and the rate increases considerably with age; 64% of men and 78% of women over 65 have HTN. High blood pressure associated with HTN can force of the blood against artery walls with enough pressure that it can eventually cause health problems, such as heart disease and stroke. HTN is one of the most significant causes of early death worldwide and one of the most preventable causes of death. Many studies reveal that lowering blood pressure (BP) reduces the incidence of diseases of the heart and blood vessels. Non-drug related treatments are known to reduce BP which can have a great effect on public health. Research suggests that Tai Chi (TC) is effective in lowering BP in patients with HTN, but because of the low quality of existing studies there is no definite proof. Also, it is not known how TC reduces BP. One possibility is that TC practice, which is shown to reduce psychological distress such as anxiety and depression and reduce the body's responses to stress, can improve the balance of the autonomic nervous system (the part of your nervous system that controls beating of the heart and the widening or narrowing of blood vessels). This may lead to lower BP. The investigators plan to investigate the pathways among autonomic, blood vessel, immune and psychological factors in relation to BP changes in response to 12-weeks of TC compared with Healthy Aging Practice-centered Education (HAP-E). 250 older adults (60+ years old) with mild HTN will be enrolled, and the investigators will take several measurements of heart and nervous system functioning. The investigators hypothesize that performing TC for 12 weeks will result in autonomic "re-regulation" which will improve BP and blood vessel health (Aim 1) and sympathetic nervous system (part of the nervous system that serves to speed up heart rate, contract blood vessels, and raise blood pressure) regulation of the immune system (Aim 2). Lastly, the investigators hypothesize that psychological factors will be related to TC effects on autonomic regulation (Aim 3). Findings from the investigators study will hopefully shed light on the pathways by which TC reduces BP. Also, the particular effects of TC ("meditative movement") in an older, "hard-to-treat" hypertensive population will be better understood.
Investigators
Laura S. Redwine, PhD
Asst Adjunct Prof
University of California, San Diego
Eligibility Criteria
Inclusion Criteria
- •SBP≥130 but overall BP ≤ 170/110;
- •Able to perform light to moderate exercise;
- •Able to give informed consent;
- •Able to complete study assessments as described;
- •Understand study procedures and to comply with them for the entire length of the study;
- •Able to complete written questionnaires without assistance (reading devices okay);
- •Have not had a fall in that resulted in hospitalization in the past 12 months;
- •Willing to be randomized to TC or HAP-E;
- •Able to attend regular study activities at the center and/or UCSD.
Exclusion Criteria
- •Currently performing meditation for more than 15 minutes at a time 2X/week or more);
- •Currently performing moderate exercise (enough to work up a sweat) for more than 15 minutes 2X/week or more.
- •Oxygen-dependent COPD;
- •Stroke, cerebral neurologic impairment, cardiac surgery or MI within the past year;
- •Current use of mood stabilizers, or antipsychotics;
- •Medications (steroids) and conditions affecting our immune assays or our physiological measures of vascular function (anti-cholinergics);
- •Severe kidney disease;
- •Current cancer diagnosis or treatment;
- •Insulin-dependent diabetes mellitus;
- •Meets criteria for bipolar disorder, schizophrenia, substance use disorder;
Outcomes
Primary Outcomes
Blood Pressure
Time Frame: Pre- to post-intervention (12 weeks)
Change From Pre-intervention to Post-intervention in Blood Pressure (mmHg)
Secondary Outcomes
- Stroke Volume(Pre- to post-intervention (12 weeks))
- Pulse Wave Velocity (PWV)(Pre- to post-intervention (12 weeks))
- Cardiac Output(Pre- to post-intervention (12 weeks))
- Ejection Fraction (EF)(Pre- to post-intervention (12 weeks))
- Total Peripheral Resistance (TPR)(Pre- to post-intervention (12 weeks))
- Heart Rate Variability (HRV)(Pre- to post-intervention (12 weeks))