Date of Award
Master of Science
Purpose: To evaluate the independent and combined associations of cardiorespiratory fitness (CRF) and muscular strength (MS) with arterial stiffness (AS) in older adults.
Methods: This cross-sectional study included 427 older adults aged ≥65 years (mean age 72). CRF was assessed by time (seconds) to complete a 400-m walk test and MS by overall grip strength (maximum out of 3 trials on each hand, averaged; Jamar Plus+ 12-064). Carotid-femoral pulse wave velocity (PWV) was used to assess AS (AtCor, Sphygmocor Xcel). High AS was defined as a PWV of 10 m/s or greater, as it has been established as a threshold for increased cardiovascular risk. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs) of having high AS across sex-specific tertiles of CRF and MS. Linear and logistic regression were used to investigate the independent associations between CRF or MS with AS. Further, CRF and MS were dichotomized into either weak or unfit (lower one-third for each), or strong or fit (upper two-thirds for each) to investigate the combined associations of CRF and MS with high AS.
Results: Sixty-three (17 %) adults were identified as having high AS. In logistic regression, compared to lower CRF (lowest 33%), ORs (95% CIs) of having high AS were 0.44 (0.23-0.85) and 0.46 (0.25-0.94) for middle and upper CRF, respectively, after controlling for age and sex. After further adjustment for mean arterial pressure (MAP) and lifestyle factors, only middle CRF remained significant (OR, 0.48 [95% CI 0.25-0.94]). Compared to lower MS (lowest 33%), ORs (95% CIs) of having high AS were 0.40 (0.20-0.80), 0.32 (0.15-0.70), and 0.34 (0.15-0.77) for upper MS, after adjustment for age and sex, further for MAP and lifestyle factors, and further for CRF, respectively. In the joint analysis, compared to Unfit & Weak, ORs (95% CIs) of having high AS were 0.32 (0.13-0.80), 0.35 (0.13-0.93), and 0.27 (0.12-0.60) for Unfit & Strong, Fit & Weak, and Fit & Strong groups, respectively.
Conclusion: Higher levels of both CRF and MS appeared to be associated with a lower prevalence of increased (high) arterial stiffness in older adults.
Albin, Emma Elizabeth, "Associations of cardiorespiratory fitness and muscular strength with arterial stiffness in older adults" (2019). Graduate Theses and Dissertations. 16957.