Absolute And Relative Reliability Of Vascular Biomarkers Measured Non-invasively

PURPOSE: The purpose of this investigation was to assess the absolute and relative reliability of vascular biomarkers through a non-invasive, commercially available device. METHODS: Twenty-one (21.0 ± 2.0 yrs; 154.9 ± 31.3 cm; 66.9 ± 3.1 kg) college-aged males (n = 9) and females (n = 12) visited the laboratory on two separate occasions at relatively the same time of day (±2 hours). Participants were instructed to fast for 12 hours, abstain from alcohol for at least 6 hours, and avoid tobacco and caffeine for at least 4 hours. A brachial cuff (CONNEQT Pulse) was placed most proximally on the right arm with subjects laying in a supine position. Following five minutes of rest, two measurements were taken with one minute of rest interspaced. The lower reading was used for analyses, however, if BSBP and/or BDBP values differed by more than 5 mmHg, a third measurement was obtained and averaged for analyses. Intra-class correlation coefficients (two-way random, absolute agreement [ICC 2,1]) and standard error of the measurement (SEM) were performed to examine relative and absolute reliability, respectively, as well as to determine the minimal difference (MD). RESULTS: BSBP (ICC 2,1 = 0.673; SEM = 6.1 mmHg; MD = 16.8 mmHg), BDBP (ICC 2,1 = 0.710; SEM = 4.4 mmHg; MD = 12.3 mmHg), CSBP (ICC 2,1 = 0.675; SEM = 5.2 mmHg; MD = 14.5 mmHg), and CDBP (ICC 2,1 = 0.746; SEM = 4.3 mmHg; MD = 11.9 mmHg) demonstrated moderate reliability, while AIx (ICC 2,1 = 0.766; SEM = 3.6 mmHg; MD = 10.0 mmHg) demonstrated good reliability. CONCLUSION: The CONNEQT Pulse demonstrated moderate to good reliability of several vascular biomarkers. Thus, our findings suggest that the CONNEQT Pulse may be used as a robust, non-invasive assessment of arterial health.