Low-frequency and low-intensity ultrasound increases cardiac parasympathetic neural activity and decreases clinic hypertension in elderly hypertensive subjects with type 2 diabetes.

Background: The aims of the present study were to determine the effects of an ultrasound irradiation on clinic hypertension and the heart rate variability in elderly hypertensive subjects with type 2 diabetes.

Methods: We examined the effects of ultrasound (800 kHz, 25 mW/cm) applied to the forearm for 10 min on the autonomic nerve activity and the difference between BP at home and at a clinic visit in Japanese subjects with type 2 diabetes and hypertension.

Results: In 108 subjects who displayed systolic BP (SBP) >140 mm Hg at a clinic visit, 75 subjects (69%) had a mean SBP <135 mm Hg at home and 33 subjects (31%) had a mean SBP >135 mm Hg at home in the morning for 14 days.

Low-frequency and low-intensity ultrasound irradiation to the forearm improves an index of arterial stiffness in subjects with type 2 diabetes and hypertension.

Objectives: The arterial pressure-volume index (API) is a non-invasive assessment of arterial stiffness, and is suggested as a useful predictor of future cardiovascular events. The aim of the present study was to determine the effects of low-frequency and low-intensity ultrasound applied to the forearm for 10 min on the API in Japanese subjects with type 2 diabetes and hypertension.

Methods: We examined the effects of low-frequency and low-intensity ultrasound (800 kHz, 25 mW/cm) applied to the forearm for 10 min on the API, blood pressure (BP) and pulse rate in 40 Japanese subjects (13 men and 27 women; mean age ± SE, 70 ± 2 years) with type 2 diabetes and hypertension, who had the API > 30 and systolic BP > 140 mmHg at a clinic visit.