Low-frequency and very low-intensity ultrasound decreases blood pressure in hypertensive subjects with type 2 diabetes

Abstract

Background: Despite lifestyle interventions and various types of anti-hypertension agents, hypertension remains difficult to control in some patients with type 2 diabetes. As a noninvasive device-based approach for the treatment of clinic hypertension, we examined the effects of low-frequency and low-intensity ultrasound (500 or 800kHz, 25mW/cm(2)) applied to the forearm on blood pressure (BP) and pulse rate in Japanese subjects with type 2 diabetes and hypertension.

Methods: We examined the effects of low-frequency and low-intensity ultrasound (500 or 800kHz, 25mW/cm(2)) applied to the forearm on BP, pulse rate, and pulse pressure in 212 Japanese subjects (82 men and 130 women; mean age±SE, 65±1years) with type 2 diabetes and hypertension (systolic BP>140mmHg). The subjects were treated with anti-hypertension agents.

Results: Systolic and diastolic BP, pulse rate, pulse pressure in the 800-kHz ultrasound treatment group were significantly lower than the baseline values in hypertensive subjects with type 2 diabetes, and lower than those of placebo controls. In addition, systolic and diastolic BP, pulse rate, and pulse pressure in the 500-kHz ultrasound treatment group were significantly lower than the baseline values in hypertensive subjects with type 2 diabetes, and systolic BP, pulse rate, and pulse pressure were significantly lower than those of placebo controls.

Conclusions: Low-frequency (800kHz or 500kHz) and low-intensity (25mW/cm(2)) ultrasound irradiation to the forearm might have potential usefulness as a therapeutic application for clinic hypertension in subjects with type 2 diabetes.

Keywords: A device-based approach; Blood pressure; Forearm; Hypertension; Type 2 diabetes; Ultrasound irradiation.