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

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 800 kHz, 25 mW/cm2) 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 800 kHz, 25 mW/cm2) applied to the forearm on BP, pulse rate, and pulse pressure in 212 Japanese subjects (82 men and 130 women; mean age ± SE, 65 ± 1 years) with type 2 diabetes and hypertension (systolic BP > 140 mmHg). 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 (800 kHz or 500 kHz) and low-intensity (25 mW/cm2) ultrasound irradiation to the forearm might have potential usefulness as a therapeutic application for clinic hypertension in subjects with type 2 diabetes.