NCT03857490

Heat Therapy in Older Hypertensive Women

Completed NA Last updated 6 March 2026

What this trial tests

NA trial testing Lower leg heat therapy in Essential Hypertension in 134 participants. Completed in 31 December 2025.

Timeline

29 July 2019

Primary endpoint
17 September 2025

31 December 2025

Quick facts

Lead sponsor	University of Texas Southwestern Medical Center
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	single
Primary purpose	treatment
Enrollment	134
Start date	29 July 2019
Primary completion	17 September 2025
Estimated completion	31 December 2025
Sites	1 location across United States

Drugs / interventions tested

• Lower leg heat therapy

Conditions studied

• Essential Hypertension — all drugs for Essential Hypertension →

Sponsor

University of Texas Southwestern Medical Center

Who can join

Adults 60 to 85, female only, with Essential Hypertension. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

The prevalence of hypertension is greater in older women than men, while the blood pressure (BP) control rate is lower in older women in US. Uncontrolled hypertension is a major risk factor for cardiovascular morbidity/mortality. Despite standard therapy and adherence to optimal drug regimens, \>50% of older hypertensive women still have inadequate BP control, and the control rate is further reduced with more aggressive BP targets recommended recently by the new Hypertension Guidelines. Thus, the effectiveness of drug treatment alone in the control of hypertension among older women is limited; hence, non-pharmacological approaches are also needed to help reduce BP in older hypertensive women. One adjuvant, non-pharmacological approach that offers promise in lowering BP is "heat therapy". Indeed, repeated whole-body heat exposure decreases BP in healthy humans. Whether this is also true after regional limb heating in hypertensive patients is unknown. The objectives of this research are to investigate the BP lowering effect of home-based lower leg heat therapy in older women with hypertension, and to examine the impact of this therapeutic modality on neural-vascular health in these patients. Aim 1 will test the hypothesis that chronic lower leg heat therapy combined with an antihypertensive drug is superior to drug treatment alone in lowering BP in older hypertensive women. We will randomly assign older hypertensive women to either an intervention group or a control group. Patients in the intervention group will perform 8 weeks of lower leg heat therapy via water immersion up to the knee in a circulated bath (water temperature 42°C, 4 times/week, 45 min/session), whereas patients in the control group will immerse their legs in a thermoneutral water bath (33°C) at the same frequency and duration. All patients will also receive a fixed dose of chlorthalidone (a diuretic, 25 mg orally daily). We will compare ambulatory BP, the BP control rate, and patient adherence and acceptability to treatment between the groups. Aim 2 will test the hypothesis that chronic lower leg heat therapy will improve nitric oxide bioavailability which can decrease sympathetic vasoconstriction and improve vascular function in older hypertensive women. We will use state-of-the-art techniques of microneurography, Doppler ultrasound, applanation tonometry, and cutaneous microdialysis to assess neural control, vasodilator function, and interstitial metabolites (i.e. nitrate and nitrite) indicative of basal nitric oxide bioavailability in all patients enrolled in Aim 1 before and after 8 weeks of heat therapy. Information obtained from this research project will guide evidence-based clinical practice. It is anticipated that our study may lead to revision of hypertension guidelines to incorporate home-based heat therapy as adjuvant to antihypertensive drug(s) for older women, as well as other patient populations.

Publications & conference data

No peer-reviewed publications indexed yet for this trial. Completed trials usually publish results within 12-18 months.