Clinical Trial Details
— Status: Enrolling by invitation
Administrative data
| NCT number |
NCT02270216 |
| Other study ID # |
KhonKaenU |
| Secondary ID |
|
| Status |
Enrolling by invitation |
| Phase |
N/A
|
| First received |
October 14, 2014 |
| Last updated |
October 17, 2014 |
| Start date |
May 2014 |
Study information
| Verified date |
October 2014 |
| Source |
Khon Kaen University |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
Thailand: Khon Kaen University Ethics Committee for Human Research |
| Study type |
Interventional
|
Clinical Trial Summary
Aim to study the exercise responses to both static and dynamic exercise in elderly people
with and without essential isolated systolic hypertension, seeking to identify potentially
dangerously high responses
Description:
1. Design The proposed study is of a experimental study design. The study will be subject
to approval by the Ethical committee of Khon Kaen University and subjects will be asked
to give their written agreement to participate.
2. Subjects Elderly subjects with isolated systolic hypertension will be recruited from
primary care units in the community and outpatient department of Srinakarind hospital
in Khon Kaen province. Healthy normotensive subjects living independently with normal
physical activity will be recruited from the same community.
Inclusion criteria: Subjects should be over 60 years of age with essential isolated
systolic hypertension (stage I-II base on recommendation of JNC-VII) for the
hypertension group and normal blood pressure in the healthy group. Good communication,
independent physical activity. The healthy subject should be non-smokers, non-obese,
free of any signs or symptoms of disease as revealed by medical history Exclusion
criteria: Essential hypertension stage III or secondary hypertension, any history of
respiratory disease, heart disease, renal disease, blindness, cerebrovascular disease,
exercise limited by pain Subjects who have passed the inclusion criteria and exclusion
criteria will undertake a dynamic exercise test and a static hand-grip exercise pressor
test in the cardiopulmonary research room , Khon Kaen University
3. Outcome measurements The main outcome measures will be changes in blood pressure and
heart rate during the two forms of exercise.
Blood pressure: Blood pressure will be measured with a digital bedside monitor (Figure
1). An inflatable cuff placed around the subject's arm one inch above the patient's
elbow over the brachial artery. Resting blood pressure will be measured in a sitting
position after having rested for 15 minutes Heart rate: Heart rate will be measured at
rest and during exercise. ECG electrode will be attached in lead II configuration and
connected to the BIOPAC system. The heart rate will be determined from the R-R interval
with the data analyzed by the BIOPAC system.
4. Procedures and protocol After an interview where they will be informed about the
various tests and asked to provide their informed consent, the subjects will undertake
two different exercise tests, the order of which will be in a randomized and balanced
design. The subjects will be asked not to smoke, take alcohol or caffeinated drinks
within 2 hours before testing.
Cycling exercise: The dynamic exercise will be with the subject sitting on a cycle
ergometer (Monark 828 E). Resting heart rate will be measured for 2 minutes before the
start of exercise. The exercise level will be limited to 50% of the estimated maximum
heart rate reserve. Maximum heart rate will be estimated as 207-0.7*age (Gellish et
al., 2007) and heart rate reserve (HRR) as maximum minus resting heart rate. Subjects
will pedal at 50 rpm for 1 min with no load and then 3 minutes against a load of 0.5 Kp
(25W) increasing to a load of 1 Kp for the next 3 minutes and to 1.5 Kp, if necessary,
for a further 3 minutes until the target heart rate of 50% HRR is reached.
Subjects will be asked about their level of perception of dyspnea using a visual analog
scale every 3 minutes at the end of each load.
Static exercise pressor response: The static exercise pressor response will be tested
using isometric handgrip of the left hand. The forearm will be supported on an arm rest
with elbow flexed. The maximum voluntary contraction force will be measured as the best
of three attempts. After 2 minute rest, subjects will perform 2 minute of isometric
hand grip contraction at 30% MVC. Circulatory occlusion(50 mmHg supra-systolic
pressure) will start at 1.30 min and continued for 2 minute after the end of the
isometric handgrip exercise. Following release of the cuff there will be a further 2
minutes recovery. The blood pressure and heart rate will be measured at the end of each
minute during rest, isometric handgrip, circulatory occlusion and recovery. Subjects
will be instructed to breathe normally during the test and avoid any Valsalva maneuver;
breathing frequency will be monitored during the handgrip pressor test using
capnography.
5. Data and statistical analysis Data will be expressed as mean ± SD. Changes of data
during and post test from baseline. Will be tested by paired t-test. Significance were
set at P<0.05.
