Premium
Reliability of orthostatic responses in healthy men aged between 65 and 75 years
Author(s) -
Gabbett Tim J.,
Gass Greg C.
Publication year - 2005
Publication title -
experimental physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.925
H-Index - 101
eISSN - 1469-445X
pISSN - 0958-0670
DOI - 10.1113/expphysiol.2005.030387
Subject(s) - supine position , reproducibility , intraclass correlation , medicine , orthostatic vital signs , heart rate , coefficient of variation , cardiology , blood pressure , diastole , mathematics , statistics
The purpose of this study was to investigate the short‐, medium‐ and long‐term reproducibility of cardiovascular responses during 90° head‐up tilt (HUT) in healthy older men. Twenty‐eight healthy male subjects aged 69 (95% confidence intervals, 68–70) years participated in the study. Eight subjects underwent duplicate 90° HUT tests on consecutive days, while 20 subjects underwent four 90° HUT tests performed at baseline, and after 1 week, 1 month and 1 year. Following a 20‐min supine resting period, each subject was rapidly tilted to the upright vertical position (90° HUT) and remained in that position for 15 min. Beat‐by‐beat recordings of mean (MAP), systolic (SBP) and diastolic (DBP) pressures were made via Finapres, while heart rate (HR) was monitored continuously from an electrocardiogram. No significant test–retest differences ( P > 0.05) were observed for the changes in HR, MAP, SBP or DBP during 90° HUT. These measurements demonstrated high reproducibility (intraclass correlation coefficient, r = 0.91–0.99, P < 0.05). The supine resting and tilted HR, MAP, SBP and DBP over the 1‐week, 1‐month and 1‐year period were not significantly different ( P > 0.05) from baseline, and demonstrated high reproducibility (intraclass correlation coefficient, r = 0.82–0.98, P < 0.05). The results of this study demonstrate that in healthy older men, cardiovascular responses during orthostasis are highly reproducible, and this reproducibility is maintained over a 12‐month period. These findings demonstrate that the 90° HUT test offers a reproducible method of monitoring longitudinal orthostatic responses in healthy older men.