M6 ac

Blood pressure was measured on the right arm, in a sitting position using electronic sphygmomanometers (OMRON M6 or OMRON M6 AC) after five minutes of rest, on three occasions, at one-minute intervals. The measurements were conducted in a private, quiet place with proper temperature. The existence of hypertension (HTN) was based on elevated systolic blood pressure (SBP), diastolic blood pressure (DBP) or both according to the latest European guidelines [29 (link)].

Brachial systolic and diastolic blood pressure were measured after 10 min of rest in a sitting position with an automated blood pressure recorder (Omron M6-AC, Omron Healthcare, Milton Keynes, UK). The blood pressure was measured three times and the average was used in the analysis. We estimated brachial pulse pressure as the difference between brachial systolic blood pressure and diastolic blood pressure.

After a 15 min period of acclimatisation to the environment (ambient temperature 24.1 (0.8)°C, relative humidity 46 (9)%), participants were asked to take a rapid, deep breath to maximum inspiratory capacity and hold it for 10 s followed by normal breathing. A practice run was conducted, after which three repeated breath‐holds were undertaken at 3 min intervals (Mueck‐Weymann & Rauh, 2002 (link)). Skin blood flow of the left thumb and great toe pad were measured before and following the respiratory manoeuvres using a single channel laser Doppler probe (VP12, Moor Instruments, Axminster, UK) inserted into an integrated heater (VHP2, Moor Instruments) clamping local skin temperature at 33°C. Outputs from the laser Doppler meter (MoorVMS‐LDF2, Moor Instruments) and heater were recorded and analysed using dedicated software (MoorVMS‐PC, v4.2, Moor Instruments). Blood pressure was recorded before and after the three respiratory manoeuvres using an automated blood pressure meter (M6 AC, Omron, Kyoto, Japan) on the contralateral arm to enable calculation of mean arterial pressure (MAP) and cutaneous vascular conductance (CVC: flux/MAP). Inspiratory gasp vascular response (IGVR) was calculated as the percentage decrease in CVC from baseline (Mayrovitz & Groseclose, 2002 (link)) with the maximum of the three IGVRs being reported.

Blood pressure (BP) was measured on the right arm, in a sitting position using an Omron digital blood pressure measuring device (OMRON M6 or M6 AC) after 5 min of rest, on three occasions, allowing 1 min interval among the occasions. Participants were asked to avoid vigorous exercise, smoking, eating or drinking for 1 h before the BP measurement. Means of the second and third measurements were used in the current statistical analysis. Participants were classified according to the European guidelines [34 (link)] in the following categories: optimal or normal (systolic BP < 130 mmHg and/ or diastolic BP < 85 mmHg), high normal (systolic BP 130-139 mmHg and/ or diastolic BP 85-89 mmHg) and hypertension (systolic BP ≥ 140 mmHg and/ or diastolic BP ≥ 90 mmHg), with the BP category to be defined by the highest level of BP, either systolic or diastolic.

Trained study nurses performed all the clinical measurements.
Height was measured to the nearest 0.1 cm in light indoor clothing without shoes, using a telescopic measuring rod (SECA Gmbh&co, Germany). Waist circumference (WC) was measured with a tape measure (m) placed midway between the iliac crest and the lowest rib. Waist-to-height ratio (WHtR) was calculated as WC (m) / height (m). Body fat (kg) and body weight (kg) were measured using the InBody 720 body composition device (InBody 3.0, Biospace, South Korea) without socks on, rounded to the nearest 0.1 kg. BMI was calculated as body weight (kg) / height (m²). Body fat (%) was calculated as body fat (kg) / weight (kg). BP was measured from each participant’s right arm with a standardized BP monitor (M6 AC, Omron Healthcare Co. Ltd., Japan), after 15 min of rest. The mean value of three BP measurements was used in the data analysis.